Contract No. 9727 - I-405, Brickyard to SR 527 Improvement Project

Protest 019 - Issue SKA-0303 - Juanita Creek Fish Passage Lateral Migration Design

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Pursuant to General Provisions (GP) 1-04.5(1), WSDOT submits this position paper and the referenced supporting documents to the Dispute Review Board (DRB or Board) for its consideration of the matter referred by the Design-Builder on Protest 019.

The Design-Builder performed a scour analysis for the Juanita Creek fish passage that accounted for lateral migration, and designed the headwall and wingwalls accordingly. The Design-Builder now contends that WSDOT's review comments on the Design-Builder's hydraulic and structural Design Documents, together with discussions at Fish Passage Task Force meetings, directed that design and therefore constitute an Owner-Initiated Change.

Statement of the Matter Referred to the Board. The matter referred to the Board is whether the Design-Builder's decision to assume lateral migration and design the Juanita Creek wingwalls for full scour depth was its own engineering judgment in performing the contractual scour analysis, or a change directed by WSDOT's review comments and Fish Passage Task Force discussions. The Board's recommendation is requested on whether a Change Order is warranted.

The Contract assigns the scour analysis for the crossing to the Design-Builder (TR 2.30.5.6), classifies the lateral migration risk at Juanita Creek (Table 2.30-B), and addresses the effect of WSDOT review comments on the Design-Builder's design responsibility (GP 1-02.1). Those provisions, the technical and documentary record, and WSDOT's position are set out in the Sections that follow.

The correspondence chain on this issue is as follows.

Date	Document	Description
January 30, 2026	Skanska Letter (LTR) No. 337	Request for Direction seeking an Owner-Initiated Change of $5,466,392
February 24, 2026	WSDOT Serial Letter (SL) No. 9727-280	Interpretive Engineering Decision on Juanita Creek lateral migration
March 10, 2026	Skanska LTR 372	Notice of Protest 019
March 16, 2026	WSDOT SL No. 9727-294	Acknowledgment of Protest 019. Extension request not granted. Supplemental due March 24, 2026
March 24, 2026	Skanska LTR 384	Supplemental Written Statement. Amount reduced to $4,615,622
April 14, 2026	WSDOT SL No. 9727-326	Written Determination that Protest 019 does not establish entitlement
April 28, 2026	Skanska LTR 417	Notice of Dispute under GP 1-04.5(1). Amount reduced to $3,179,809. DRB referral requested
(subsequent)	WSDOT SL No. 9727-345	WSDOT response acknowledging the Notice of Dispute

The Design-Builder filed its Notice of Dispute via Skanska LTR 417 on April 28, 2026, the fourteenth day of the dispute window under GP 1-04.5(1), and expressly requested referral of this matter to the Board. WSDOT submits this position paper in response.

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The I-405, Brickyard to SR 527 Improvement Project is a design-build project for highway and multimodal improvements along the I-405 corridor in the cities of Bothell and Kirkland, Washington. The Work includes the correction of fish passage barriers at six stream crossings identified in Technical Requirements (TR) 2.30 Water Crossings, in compliance with the federal culvert injunction.

Juanita Creek (I-405 milepost 21.94, Fish Passage and Diversion Screening Inventory site 998602) is one of those crossings. The Design-Builder designed a new injunction-compliant, fish-passable crossing at Juanita Creek consisting of a three-sided buried structure with a headwall and wingwalls, together with a regraded and restored stream channel. The Design-Builder is the Engineer of Record for the hydraulic and structural design of that crossing.

This matter concerns the scour analysis for the Juanita Creek crossing and the design of the headwall and wingwalls that the scour analysis informs. Specifically, it concerns whether the Design-Builder's treatment of lateral migration in that scour analysis, and the resulting wall design, were directed by WSDOT or were performed by the Design-Builder in fulfillment of its own design obligations under the Contract.

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This Section sets out the contract language that governs this matter. Each provision is quoted as it appears in the Contract Documents. Except where noted, each is a Contract Document. The WSDOT Bridge Design Manual, which contains Section 8.1.10, is a Mandatory Standard, as explained in Section 3.9. Defined terms used in WSDOT's position appear first, in Section 3.1.

3.1 Defined Terms

The following terms are defined in TR 2.30 and are used in this position paper. Each is quoted as it appears in the Contract.

Lateral Migration (Structural):

"Lateral migration of the stream channel in a manner that cuts into side slopes or hillsides above the floodplain to the extent that threatens the integrity of the roadway or structure or the loading conditions which are defined in the structural design code as a result of erosion or scour of the side slopes."

Total Scour:

"the meaning as defined by FHWA Hydraulic Engineering Circular Number 18 (HEC-18) evaluated at the Scour Design Flood and Scour Check Flood."

Structure Free Zone (SFZ), in part:

"An imaginary, rectangular prism of infinite length both upstream and downstream, that is horizontally centered on the Bearing of Stream, parallel to the Bearing of Stream, and which represents the minimum boundary within which no part of the fish passage structure, including footings, shall be allowed unless meeting the criteria for an allowable exception in this paragraph. The SFZ is bounded on top and bottom by the CTE and the CBE respectively, with minimum interior width equal to the minimum SFZ Width specified in Table 2.30-B."

Controlling Bottom Elevation (CBE), in part:

"An imaginary surface that represents the bottom boundary of the Structure Free Zone (SFZ) as depicted in the SFZ Drawings in this Section."

3.2 GP 1-02.1 Responsibility for Design

General Provisions (GP) 1-02.1 Responsibility for Design provides, in part:

"It is the intent of the Contract Documents that the Design-Builder undertake full responsibility for delivery of the Project. The Contract Documents do not provide details of the design necessary to carry out the intent of the Contract Documents. Such detailed designs are the sole responsibility of the Design-Builder to develop."

GP 1-02.1 further provides:

"Notwithstanding anything in the Contract Documents to the contrary, no field explanations or interpretations provided by WSDOT at any meetings, and no comments by WSDOT on Design Documents or Released for Construction (RFC) Documents, shall be deemed, construed, or interpreted to (a) amend, supersede, or alter the terms, requirements, limitations, or meaning of any Contract Document or (b) release or relieve the Design-Builder from full responsibility for the design of the Project in accordance with the Contract Documents."

This provision addresses the effect of WSDOT meeting explanations and WSDOT comments on Design Documents. It is a Contract Document.

3.3 GP 1-03.5 Ambiguities and Interpretive Engineering Decisions

GP 1-03.5 Ambiguities provides, in part:

"The Design-Builder may, from time-to-time, request in writing that WSDOT provide information, clarifications, and interpretations of ambiguous or uncertain design requirements set forth in the Contract Documents (an Interpretive Engineering Decision). WSDOT may issue a Written approval of the Design-Builder's proposed Interpretive Engineering Decision (if any), may issue its own Interpretive Engineering Decision or may disapprove any Interpretive Engineering Decision the Design-Builder proposes."

The same Section provides:

"no Interpretive Engineering Decision by WSDOT shall form the basis for an increase in the Contract Price or extension of the Contract Time, unless WSDOT expressly provides otherwise in writing."

And, as to the burden of proof:

"the Design-Builder shall bear the burden of proving that WSDOT's interpretation is incorrect or unreasonable."

This provision authorizes WSDOT to issue an Interpretive Engineering Decision, addresses its effect on price and time, and allocates the burden of proof. It is a Contract Document.

3.4 GP 1-03.7 Approvals and Acceptances

GP 1-03.7 Approvals and Acceptances provides:

"The oversight, spot checks, audits, reviews, tests, and inspections conducted by WSDOT do not constitute approval nor acceptance of the materials or Work inspected or reviewed."

The same Section provides that the Design-Builder:

"at all times shall have an independent duty and obligation to fulfill the requirements of the Contract Documents."

This provision addresses the effect of WSDOT review and non-action on the Design-Builder's obligations. It is a Contract Document.

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3.5 GP 1-04.1 Intent of Contract

GP 1-04.1 Intent of Contract provides:

"WSDOT and the Design-Builder both intend for the Design-Builder to assume full responsibility and liability with respect to the design of the Project, including correction of any errors, omissions, inconsistencies, or other defects in the Conceptual Design, subject only to the Design-Builder's right to a Change Order for Necessary Basic Configuration Changes."

GP 1-04.1(1) provides that the Contract Price includes:

"Compensation for all risks and contingencies assigned to the Design-Builder under the Contract Documents."

This provision allocates design responsibility and the associated cost. It is a Contract Document.

3.6 GP 1-04.4(1) WSDOT-Initiated Changes

GP 1-04.4(1) WSDOT-Initiated Changes provides:

"WSDOT reserves the right to authorize and require changes in the Work within the general scope of the Contract as provided herein."

The same Section provides:

"Changes in the Design Documents by the Design-Builder to meet Contract requirements or correct deficiencies, that do not materially change the Technical Proposal, are the responsibility of the Design-Builder and are not considered a change in the Work. No adjustment will be allowed to Contract Price or Contract Time for such changes."

This provision identifies what constitutes a WSDOT-Initiated Change and what does not. It is a Contract Document.

3.7 GP 1-04.4(5) Matters Not Eligible for Change Orders

GP 1-04.4(5) Matters Not Eligible for Change Orders provides that certain matters are the Design-Builder's exclusive responsibility, including the following at subsection (b):

"Any design changes required by WSDOT as part of the process of reviewing the Design Documents for consistency with the requirements of the Contract Documents, except to the extent directly attributable to errors, omissions, inconsistencies, or other defects in the Basic Configuration as provided herein."

This provision assigns to the Design-Builder the cost of design changes made through the design review process, with a single exception for defects in the Basic Configuration. It is a Contract Document.

3.8 GP 1-05.1 Authority, Review, and Oral Orders

GP 1-05.1 provides that authority to act for WSDOT on the Project rests with the WSDOT Engineer:

"The WSDOT Engineer represents WSDOT on the Project, with full authority to enforce Contract requirements and carry out WSDOT's orders."

GP 1-05.1 further provides that a WSDOT approval or recommendation does not bind WSDOT or relieve the Design-Builder:

"If the WSDOT Engineer approves or recommends any method or manner for doing the Work or producing materials, the approval or recommendation shall not: 1. Guarantee that following the method or manner will result in compliance with the Contract 2. Relieve the Design-Builder of any risks or obligations under the Contract 3. Create any WSDOT liability."

GP 1-05.1(1) Oral Orders provides:

"When the Design-Builder believes they have received an oral order, the Design-Builder shall notify the WSDOT Engineer in writing and within 3 Calendar Days... Failure to follow procedures of this Section will result in a waiver of claim."

This provision identifies who holds authority to direct the Design-Builder, limits the effect of a WSDOT review or recommendation, and sets out the procedure the Design-Builder must follow if it believes it has received an oral order. It is a Contract Document.

3.9 TR 2.13.4 Foundation Cover for Scour and BDM 8.1.10

TR 2.13.4 Design Criteria provides:

"Minimum foundation cover requirements for scour shall be in accordance with the WSDOT Bridge Design Manual. Existing structure foundations including spread footings, pile caps, shaft caps (or bottom of seal if used), and wall elements (including fascia panels, lagging, leveling pads, and footings) affected by the Work shall meet the minimum foundation cover requirements or be protected against scour to that level."

TR 2.13.2.1 Bridge Design Manual Rights and Responsibilities provides:

"All Chapters of the WSDOT Bridge Design Manual shall be followed as a part of the Mandatory Standard."

WSDOT Bridge Design Manual (BDM) Section 8.1.10 Scour of Retaining Walls provides:

"Total Scour includes the amount of streambed vertical elevation drop at a given location due to the removal of streambed material caused by flowing water and the effects of lateral migration."

BDM 8.1.10 sets out three design figures: Figure 8.1.10-1 for scour without lateral migration, Figure 8.1.10-2 for scour with lateral migration, and Figure 8.1.10-3 for scour with lateral migration and scour countermeasures. The Bridge Design Manual is a Mandatory Standard and a Contract Document. TR 2.13.2.1 requires that all of its chapters be followed as part of the Mandatory Standard, and it is listed as a Contract Document in Appendix D. Foundation cover for scour is incorporated through TR 2.13.4.

3.10 TR 2.30.5.2.1 Table 2.30-B and Channel Design Characteristics

Technical Requirements (TR) 2.30.5.2.1 Certain Structure and Channel Design Characteristics provides:

"The Design-Builder shall comply with the requirements of Table 2.30-B. Except as otherwise specified, where a conflict exists between Table 2.30-B and another Contract requirement, the requirements of Table 2.30-B shall take precedence."

Table 2.30-B states, for the channel characteristics at the six fish passage crossings, the following row. For I-405 milepost 21.94 (Juanita Creek):

"Is the risk of Lateral Migration (Structural) low? ... Yes"

TR 2.30.5.2.1 and Table 2.30-B establish the lateral migration risk classification for the crossing. They are Contract Documents.

3.11 TR 2.30.5.6 Scour Analysis

TR 2.30.5.6 Scour Analysis provides, in part:

"The Design-Builder shall perform a scour analysis that includes all habitat and stream restoration components in accordance with the Mandatory Standards and this Section. The analysis shall include the risk of Lateral Migration (Structural), potential for long-term degradation, and evaluation of Total Scour (long-term degradation, contraction scour, and local scour)."

The same Section assigns the Design-Builder the following evaluations:

"The Design-Builder shall make a determination of the presence of erodible soils in the streambed... This information is used to help determine the extents of vertical and lateral scour limits."

"The Design-Builder shall perform an evaluation of historical/existing conditions versus expected future conditions with the proposed stream design. Primarily, the analysis shall evaluate what the expected Lateral Migration (Structural) will be in the future, based on how the stream may adjust over the life of the structure."

"The Design-Builder shall locate, design and construct any required scour countermeasures (e.g., rock revetment) or scour protection wall to protect various WSDOT infrastructure components against total scour, including Lateral Migration (Structural). This includes an assessment of where the stream may move laterally (e.g., determining angles of attack) and vertically in relation to the various WSDOT infrastructure components."

TR 2.30.5.6 assigns the scour analysis, the lateral migration evaluation, and the scour countermeasure design to the Design-Builder. It is a Contract Document.

This Section sets out the technical and documentary record. It states facts. Section 7 sets out WSDOT's position.

4.1 The Design-Builder's Final Hydraulic Design and lateral migration assessment

The Design-Builder submitted its Final Hydraulic Design (FHD) for the Juanita Creek crossing on January 28, 2025. Section 7 of the FHD documents the scour analysis. Appendix O documents a lateral migration rapid assessment.

The Design-Builder's Appendix O states that the rapid assessment method from FHWA Hydraulic Engineering Circular No. 20 (HEC-20) was used to rate the migration potential of Juanita Creek, and that "the results of the rapid assessment indicate that Juanita Creek has low potential for lateral or vertical migration." The Design-Builder's assessment recorded field observations including bank erosion, noting that "bank erosion was encountered in various locations along Juanita," and recorded a bank soil texture of gray silty sand.

Section 7.1 of the FHD states that "there is low to moderate potential for lateral migration within the project reach." The Design-Builder's FHD further states that "although the risk for lateral migration is considered low to moderate, the risk in relation to the structure is assumed to occur for the purposes of scour analysis and estimation of total scour." The FHD states that "the geotechnical data available at this time are not sufficient to exclude the risk of lateral migration from the scour analysis" pending detailed geotechnical evaluation of soil erodibility over the life of the structure.

The Design-Builder's FHD therefore recorded the Design-Builder's own determination, on the Design-Builder's own data, to account for lateral migration in the scour analysis for the Juanita Creek structure.

4.2 The design review comments

WSDOT provided comments on the Design-Builder's Design Documents through the Resolution of Comments and Submittal Review (RCSR) process.

On the FHD, the comment the Design-Builder identifies as central is FHD RCSR Comment 196. Comment 196 reflects the Design-Builder's own analysis back to the Design-Builder and invites the Design-Builder to revise it, stating "if this is not correct, please revise." Comment 196 does not contain the word "shall."

On the preliminary structural design (Package 9), the comments the Design-Builder identifies are Comments 3 and 4, both authored by WSDOT's hydraulics reviewer. Those comments use the word "shall" in language quoted from BDM 8.1.10, and Comment 4 references Figure 8.1.10-2. The Design-Builder has identified no RCSR comment, on any submittal, that directs the Design-Builder to reclassify the Table 2.30-B lateral migration designation.

On the West Portal structural design, the Design-Builder identifies Comment 25. Comment 25 states, in relevant part, that "at the joint between the wingwall and existing MSE wall at both wingwall ends scour requirements for the new and old portion of the MSE apply."

4.3 The June and July 2025 methodology correspondence

Between June 13 and July 25, 2025, the Design-Builder's Engineer of Record and WSDOT's hydraulics reviewer exchanged a series of emails regarding the lateral migration methodology. WSDOT placed the complete thread in the record on April 14, 2026.

In an email dated June 13, 2025, the Design-Builder's Engineer of Record wrote that "to be conservative, lateral migration was assumed when conducting scour analysis." The same email states that "both tunnel and wingwalls are designed for full scour depth." The same email states that the Engineer of Record initiated the discussion "in response to a structural comment from Jason Pang related to protection of the downstream MSE at Juanita Creek."

On June 18, 2025, the Design-Builder proposed a 46-foot valley width derived from a nine-cross-section analysis. WSDOT's hydraulics reviewer responded the same day that the reviewer agreed with the Design-Builder's "estimate of lateral migration extents and documentation" and asked that it be included in the final FHD. Later the same day, the Design-Builder wrote that "we will use this as a guide to design buried riprap following HEC-23 to protect the MSE wall."

The Fish Passage Task Force minutes for July 1, 2025 record that "lateral migration defined as low in Chapter 2 still requires the limits to be determined." The minutes for July 15, 2025 record that the contract definition of low lateral migration would be followed. WSDOT completed its review of the lateral migration comments on July 28, 2025 and noted the availability of the Design-Builder Initiated Change process under GP 1-04.4(2). WSDOT's reviewer recorded that the comments were resolved "on behalf of HQ hydraulics due to the contract terms surrounding low lateral migration."

4.4 The Design-Builder's January 2026 presentation and request for direction

On January 16, 2026, the Design-Builder presented a Sediment Depth Discussion to WSDOT. On January 30, 2026, the Design-Builder issued Skanska LTR 337, a Request for Direction seeking an Owner-Initiated Change of $5,466,392.

The January 16, 2026 presentation states that "the final design of the wingwalls and headwall was completed before we received guidance to ignore lateral migration." Addressing the tunnel, the presentation states that the lateral migration treatment "did not impact depth of sediment in tunnel." Addressing the buried riprap, the presentation states that "this buried riprap is not connecting to or protecting the new structure" and that "it is protecting an existing MSE wall downstream of the structure."

The presentation also records an exchange between Skanska and the Design-Builder's Engineer of Record. On slide 8, Skanska asked why lateral migration was included at Juanita Creek, noting that it had "fought so hard to not include lateral migration at the Sammamish River but seemed to accept it here." The Engineer of Record replied that the cited FHD "was from before we received guidance to ignore lateral migration." On slide 9, asked to "depict ... how WSDOT influenced the design," the Engineer of Record stated the treatment "did not impact depth of sediment in tunnel," "did impact wingwall design," and "may have been different if received guidance on lateral migration sooner," and that a redesign would have required "significant effort."

The asserted amount has been stated three times. Skanska LTR 337 sought $5,466,392. Skanska LTR 384 stated $4,615,622. Skanska LTR 417 states $3,179,809. The Design-Builder has stated in Skanska LTR 384 and Skanska LTR 417 that the progress schedule analysis is "underway." No progress schedule analysis has been provided.

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Date	Event	Source
July 3, 2024	Design-Builder submits the Preliminary Hydraulic Design for Juanita Creek	Design-Builder submittal
July 30, 2024	WSDOT returns Preliminary Hydraulic Design comments. No lateral migration comments at this stage	RCSR record
January 28, 2025	Design-Builder submits the Final Hydraulic Design	Design-Builder submittal
February 19, 2025	WSDOT returns FHD comments, including Comment 196	Package 8 FHD RCSR
June 13, 2025	Engineer of Record email. Lateral migration "assumed when conducting scour analysis." Tunnel and wingwalls "designed for full scour depth"	June-July 2025 email thread
June 18, 2025	Design-Builder proposes 46-foot valley width. WSDOT concurs the same day. Design-Builder selects buried riprap per HEC-23	June-July 2025 email thread
July 1, 2025	Task Force minutes: "low ... still requires the limits to be determined"	TFM minutes
July 15, 2025	Task Force minutes: the contract definition of low lateral migration will be followed	TFM minutes
July 28, 2025	WSDOT completes review of the lateral migration comments. Notes GP 1-04.4(2)	WSDOT SL No. 9727-280 Section 4
December 31, 2025	Released for Construction issued for the East Portal headwall and wingwalls	RFC record
January 30, 2026	Skanska LTR 337 Request for Direction seeking $5,466,392	Skanska LTR 337
February 24, 2026	WSDOT SL No. 9727-280 Interpretive Engineering Decision	WSDOT SL No. 9727-280
March 10, 2026	Skanska LTR 372 Notice of Protest 019	Skanska LTR 372
March 16, 2026	WSDOT SL No. 9727-294 acknowledges Protest 019. Supplemental due March 24, 2026	WSDOT SL No. 9727-294
March 24, 2026	Skanska LTR 384 Supplemental Written Statement. Amount $4,615,622	Skanska LTR 384
April 14, 2026	WSDOT SL No. 9727-326 Written Determination	WSDOT SL No. 9727-326
April 28, 2026	Skanska LTR 417 Notice of Dispute. Amount $3,179,809. DRB referral requested	Skanska LTR 417

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This Section identifies the design submittals on which this matter turns and the WSDOT review comments on each. The submittals themselves, across their preliminary, final, and Released for Construction versions with the review comment forms, are collected in Appendix N.

6.1 Preliminary Hydraulic Design (BY-CRE-00858)

The Design-Builder submitted the Preliminary Hydraulic Design for Juanita Creek, dated June 2024, in July 2024. It recorded that "the risk in relation to the structure is assumed to occur for the purposes of scour analysis and estimation of total scour." WSDOT returned its review comments on July 30, 2024 and raised no comment on lateral migration. The Design-Builder had assumed lateral migration in the scour analysis on its own, before any WSDOT comment on the subject.

6.2 Final Hydraulic Design (BY-CRE-01827)

The Design-Builder submitted the Final Hydraulic Design on January 28, 2025, carrying the same lateral migration assumption, with the scour analysis in its Section 7. WSDOT returned its comments on February 19, 2025, including FHD review Comment 196, which read in part "if this is not correct, please revise." WSDOT resolved the lateral migration comments on July 28, 2025, recording that lateral migration at Juanita Creek "is defined as low and shall be followed" and that the Design-Builder would "otherwise need a DBIC." Status: comments resolved July 28, 2025.

6.3 East Portal Wall Structures (BY-CRE-02210, BY-CRE-03543, BY-CRE-04325)

The Design-Builder submitted the preliminary East Portal wall plans (BY-CRE-02210) in March 2025. WSDOT's hydraulics reviewer returned Package 9 review Comments 3 and 4, both citing BDM 8.1.10. Comment 3 asked the Design-Builder to "confirm bottom of wall is 2 feet below total scour at check flood elevation, including lateral migration (structural)," and Comment 4 directed the Design-Builder to "see Figure 8.1.10-2." The Design-Builder submitted the final plans (BY-CRE-03543) in October 2025. The dispositioned final review comment form did not re-raise BDM 8.1.10, and the one surviving scour-geometry comment was resolved and accepted. The design was Released for Construction (BY-CRE-04325) in December 2025. Status: Released for Construction.

6.4 West Portal Wall Structures (BY-CRE-02327, BY-CRE-03550, BY-CRE-04750)

The Design-Builder submitted the preliminary West Portal wall plans (BY-CRE-02327) in March 2025. WSDOT's structural reviewer returned Comment 25, citing BDM 7.1.7, which stated that "at the joint between the wingwall and existing MSE wall at both wingwall ends scour requirements for the new and old portion of the MSE apply." The Design-Builder submitted the final plans (BY-CRE-03550) in July 2025, and the design was Released for Construction (BY-CRE-04750). Status: Released for Construction.

WSDOT's position rests on the contract provisions in Section 3 and the record in Section 4. Each line of reasoning below connects a fact in the record to a provision of the Contract.

Did WSDOT direct the Design-Builder to assume lateral migration and design the Juanita Creek wingwalls for full scour depth? Or was that the Design-Builder's own engineering judgment in performing the contractual scour analysis?

It was the Design-Builder's own engineering judgment. WSDOT did not direct it, and the cost of the Design-Builder's design judgments rests with the Design-Builder.

7.1 The lateral migration design was the Design-Builder's own engineering judgment

The Contract assigns the scour analysis to the Design-Builder. TR 2.30.5.6 provides that "the Design-Builder shall perform a scour analysis" that "shall include the risk of Lateral Migration (Structural)," that "the Design-Builder shall make a determination of the presence of erodible soils," that "the Design-Builder shall perform an evaluation of ... what the expected Lateral Migration (Structural) will be in the future," and that "the Design-Builder shall locate, design and construct any required scour countermeasures ... against total scour, including Lateral Migration (Structural)."

The Design-Builder performed that analysis. Its own Final Hydraulic Design found "low to moderate potential for lateral migration within the project reach" and stated that the available geotechnical data were "not sufficient to exclude the risk of lateral migration from the scour analysis" (Section 4.1). On that record, the Design-Builder's Engineer of Record wrote that "to be conservative, lateral migration was assumed when conducting scour analysis," and that "both tunnel and wingwalls are designed for full scour depth" (Section 4.3). The decision to assume lateral migration and to design the wingwalls for full scour depth was the Design-Builder's own conservative engineering judgment, made in performing the scour analysis the Contract assigns to it. Under GP 1-02.1, the detailed design of the Project is "the sole responsibility of the Design-Builder to develop". That judgment, and the design that followed from it, are not a WSDOT-Initiated Change.

The Design-Builder reached this judgment before any WSDOT comment on lateral migration. It assumed lateral migration in its Preliminary Hydraulic Design (dated June 2024), which recorded that "the risk in relation to the structure is assumed to occur for the purposes of scour analysis and estimation of total scour," and WSDOT's review of that report raised no lateral migration comment. It assumed lateral migration again in its Final Hydraulic Design (January 2025), which set the wingwall scour at full depth, with lateral migration assumed to occur. WSDOT did not comment on the Final Hydraulic Design until February 2025. The structural design followed the Design-Builder's own hydraulic design. The preliminary structural plans submitted in March 2025 state on their face that the structure "has been designed for scour in accordance with the hydraulic report dated June 2024," and the final structural plans update that basis to the "final hydraulic report dated January 2025." The wingwall foundation in those preliminary plans was already a deep soldier-pile wall founded well below the channel and well below the bottom-of-scour line. The lateral migration design basis was in place, and keyed to the Design-Builder's own hydraulic reports, before WSDOT commented on it.

7.2 The Table 2.30-B "low" classification and the analysis-and-design obligation coexist

The Design-Builder's theory depends on treating the Table 2.30-B answer of "low" as if it removed the obligation to analyze and design for lateral migration. It does not. Table 2.30-B answers a single question for the crossing: "Is the risk of Lateral Migration (Structural) low?" The answer for Juanita Creek is "Yes". That answer classifies the level of risk. It is a separate matter from the scour analysis obligation in TR 2.30.5.6, which requires the Design-Builder to include "the risk of Lateral Migration (Structural)" in the analysis and to evaluate what the expected future lateral migration will be at the structure. A classification of "low" states the level of the risk. It is not a finding of no migration, and it does not remove the obligation to evaluate the migration's effect on the structure. It is also a separate matter from BDM 8.1.10, the Mandatory Standard for retaining wall scour, under which "Total Scour includes ... the effects of lateral migration" for retaining walls near water.

A risk classification of "low" and a design standard that evaluates total scour including lateral migration operate together. The contract text supports both at once and identifies no conflict between them. There is no provision under which a "low" classification excuses the Design-Builder from the TR 2.30.5.6 analysis or from the BDM 8.1.10 total scour evaluation.

The Design-Builder's argument rests on a conflict between the "low" classification and the scour standard, with Table 2.30-B controlling. The Contract gives Table 2.30-B that precedence only "except as otherwise specified," and it specifies otherwise for scour: where scour requires a foundation deeper than the Controlling Bottom Elevation of the SFZ, or set back farther from the stream than the SFZ Width allows, "the scour specifications shall control." BDM 8.1.10 provides that "Total Scour includes ... the effects of lateral migration," and TR 2.30.5.6 requires the Design-Builder to assess "where the stream may move laterally ... in relation to the various WSDOT infrastructure components." So where that total scour, lateral migration included, requires a deeper or farther foundation than the fish passage envelope would allow, the scour requirement controls and the envelope yields. The Design-Builder's argument inverts that rule, letting the "low" classification cap the scour design the Contract makes controlling. In any event, GP 1-03.2 Order of Precedence operates only where an actual conflict exists, and a low risk classification does not conflict with the obligation to evaluate and design for total scour.

The cost of the design follows the same allocation of responsibility. Whether the lateral migration design is viewed as part of the scour analysis the Contract required or as a conservative measure the Design-Builder elected, it is design work. GP 1-04.1(1) provides that the Contract Price includes "compensation for all risks and contingencies assigned to the Design-Builder", and detailed design is the Design-Builder's sole responsibility under GP 1-02.1. A design the Design-Builder performed to satisfy or exceed the Contract's requirements is within the Contract Price, not a basis for a Change Order.

7.3 The review comments did not amend the Contract or direct a change

The Design-Builder characterizes WSDOT's RCSR comments as direction. GP 1-02.1 addresses that characterization directly. It provides that "no comments by WSDOT on Design Documents or Released for Construction (RFC) Documents, shall be deemed, construed, or interpreted to (a) amend, supersede, or alter the terms, requirements, limitations, or meaning of any Contract Document or (b) release or relieve the Design-Builder from full responsibility for the design of the Project". GP 1-02.1 makes no exception based on the tone, the wording, or the practical effect of a comment. It applies to all comments on Design Documents.

The specific comments confirm the point. Comment 196 reflects the Design-Builder's own analysis back to the Design-Builder and invites revision, stating "if this is not correct, please revise" (Section 4.2). That language describes the Design-Builder's own analysis and invites the Design-Builder to revise it. Comment 196 went to how the Design-Builder stated its risk conclusion, not to the scour the walls were designed for. The Design-Builder had assumed lateral migration occurs and set the wingwall scour at full depth on that assumption, independent of whether the conclusion read "low" or "not low." A comment on the wording of the conclusion did not change that scour. Package 9 Comments 3 and 4 cite BDM 8.1.10 by name and point the Design-Builder to the applicable figure. Comment 3 reads "See BDM 8.1.10 Scour of Retaining Walls" and asks the Design-Builder to "confirm bottom of wall is 2 feet below total scour at check flood elevation, including lateral migration (structural)." Comment 4 likewise cites "BDM 8.1.10 Scour of Retaining Walls" and directs the Design-Builder to "see Figure 8.1.10-2." The "shall" in those comments is quoted from BDM 8.1.10. It is the Mandatory Standard that uses "shall," not a new WSDOT requirement, and BDM 8.1.10 is the section that governs scour of retaining walls including lateral migration.

The structural plans confirm that these comments did not drive the wingwall foundation. They show that scour does not govern the foundation depth. On the East Portal the bottom-of-scour elevation is essentially identical in the preliminary and final plans, EL 214.25 and EL 214.23, and the preliminary wingwall toe already sat 17 to 24 feet below it, far more than the 2-foot cover BDM 8.1.10 requires. The scour requirement was static and was satisfied many times over before any pile was deepened. The requirement Comment 3 asked the Design-Builder to confirm, that the bottom of the wall be 2 feet below total scour, was already met in the preliminary design by an order of magnitude. The Design-Builder added the explicit bottom-of-scour line and that 2-foot dimension to the plan sections at the final submittal to document compliance with the Mandatory Standard, but the scour elevation itself, and the deep soldier-pile foundation set well below it, were already drawn in the preliminary plans. The three East Portal wingwall piles nearest the headwall were deepened by five feet at the final submittal, in the same revision that raised the wingwall design height, but that change cannot be a scour response, because the scour line did not move and the wall already exceeded the scour requirement. The foundation depth is governed by the retained height and global stability, not by scour. The West Portal confirms the point. Its wingwall embedment did not change across the preliminary, final, and Released for Construction plans, even though the bottom-of-scour elevation there was raised approximately seven feet at the Released for Construction stage. A comment asking the Design-Builder to confirm that its wall met a BDM 8.1.10 figure did not create a foundation the Design-Builder had already founded well below the scour line in its own hydraulic design.

A WSDOT-Initiated Change has a defined contractual form. GP 1-04.4(1) provides that "WSDOT reserves the right to authorize and require changes in the Work". The record contains no Written Change Order and no order from WSDOT authorizing and requiring a change to the lateral migration design. The same Section provides that design changes by the Design-Builder "to meet Contract requirements or correct deficiencies ... are the responsibility of the Design-Builder and are not considered a change in the Work".

The Design-Builder's characterization also assumes that a review comment can direct the Work. It cannot. Authority to direct the Design-Builder rests with the WSDOT Engineer. GP 1-05.1 provides that the WSDOT Engineer "represents WSDOT on the Project, with full authority to enforce Contract requirements and carry out WSDOT's orders." A review comment, and an individual reviewer's view expressed in the course of design review, are not an exercise of that authority. GP 1-05.1 confirms that a WSDOT approval or recommendation does not "Guarantee that following the method or manner will result in compliance with the Contract," does not "Relieve the Design-Builder of any risks or obligations under the Contract," and does not "Create any WSDOT liability". No authorized direction to account for lateral migration issued from the WSDOT Engineer.

The Contract also addresses the Design-Builder's characterization on its own terms. To the extent the Design-Builder contends that the comments or the Task Force discussions amounted to an oral order, GP 1-05.1(1) required the Design-Builder, when it "believes they have received an oral order," to "notify the WSDOT Engineer in writing and within 3 Calendar Days". The record contains no such notice.

7.4 The Interpretive Engineering Decision was properly issued and does not create entitlement

The Design-Builder contends that WSDOT SL No. 9727-280 is not a proper Interpretive Engineering Decision because the Design-Builder did not request it. GP 1-03.5 provides that WSDOT "may issue its own Interpretive Engineering Decision". No request by the Design-Builder is required.

Two further provisions of GP 1-03.5 govern the consequence. First, "no Interpretive Engineering Decision by WSDOT shall form the basis for an increase in the Contract Price or extension of the Contract Time, unless WSDOT expressly provides otherwise in writing". WSDOT has not provided otherwise. Second, the Design-Builder "shall bear the burden of proving that WSDOT's interpretation is incorrect or unreasonable". The Design-Builder's reading, under which a "low" classification removes the TR 2.30.5.6 analysis obligation and the BDM 8.1.10 total scour obligation, is not supported by the text of either provision.

7.5 There was no constructive direction, and no defect in the Basic Configuration

Skanska LTR 384 advances a theory of "constructive direction," under which the cumulative effect of review comments operated as direction even though no single comment did. The Contract does not recognize that theory. GP 1-02.1 applies to "no comments," without limitation as to number or cumulative effect. GP 1-04.4(1) requires WSDOT to "authorize and require" a change. The contractual line is the presence or absence of a WSDOT directive, and the record contains none.

GP 1-04.4(5) places the cost of design review changes on the Design-Builder, with one exception: changes "directly attributable to errors, omissions, inconsistencies, or other defects in the Basic Configuration". That exception does not apply here. The Basic Configuration consists of the high-level geometric elements of the Project. The relationship between the Table 2.30-B "low" classification and the BDM 8.1.10 total scour standard is not a defect in the Basic Configuration. As set out in Section 7.2, the two operate together and present no conflict. The design changes the Design-Builder describes are attributable to the Design-Builder's own scour analysis under TR 2.30.5.6, not to any defect in the Basic Configuration.

The Design-Builder also had contractual avenues if it believed a comment exceeded the Contract. GP 1-04.5 provides a protest procedure with a 14-calendar-day window, and GP 1-04.4(2) provides a Design-Builder Initiated Change process. The record shows the Design-Builder proceeding through the preliminary, final, and Released for Construction stages of the wall design over approximately ten months without invoking either mechanism on the lateral migration comments.

The Design-Builder's argument that it had no practical discretion, because comment resolution was a prerequisite to Release for Construction, does not change this. That a comment must be resolved before a submittal is Released for Construction is a feature of the design review process for every comment. It does not convert the content of a comment into a change in the Work. GP 1-04.4(1) provides that changes the Design-Builder makes "to meet Contract requirements or correct deficiencies" are not a change in the Work and warrant no adjustment to Contract Price or Contract Time. Package 9 Comments 3 and 4 asked the Design-Builder to confirm its wall met BDM 8.1.10, an existing Mandatory Standard. A comment that asks the Design-Builder to confirm compliance with a requirement the Contract already imposes asks only that the Design-Builder meet the Contract. The review enforces the Contract. It does not enlarge it.

WSDOT held to the Contract throughout. When it resolved the lateral migration comments on July 28, 2025, WSDOT's reviewer recorded that it did so "due to the contract terms surrounding low lateral migration" (Section 4.3). WSDOT SL No. 9727-280 Section 4 records the same resolution, that "lateral migration at Juanita Creek is defined as low and shall be followed," and that the Design-Builder would "otherwise need a DBIC." That is the opposite of directing a departure from the Table 2.30-B classification. WSDOT confirmed the classification and identified the Design-Builder Initiated Change process under GP 1-04.4(2) as the contractual route if the Design-Builder sought to depart from it.

WSDOT's review of the design, and its allowing the design to proceed, did not convert the Design-Builder's own design judgment into a compensable change. GP 1-03.7 provides that WSDOT's "oversight, spot checks, audits, reviews, tests, and inspections ... do not constitute approval nor acceptance", and that the Design-Builder "at all times shall have an independent duty and obligation to fulfill the requirements of the Contract Documents". The cost of the Design-Builder's own design judgment rests with the Design-Builder under GP 1-02.1 and GP 1-04.1.

7.6 The record shows review and concurrence, not rejection or reversal

Skanska LTR 384 describes a five-month sequence in which WSDOT is said to have rejected the Design-Builder's methodologies and then reversed position. The contemporaneous record does not support that description. On June 18, 2025, the Design-Builder proposed a 46-foot valley width and WSDOT concurred the same day, agreeing with the Design-Builder's "estimate of lateral migration extents" (Section 4.3). That is concurrence with the Design-Builder's own analysis, not rejection of it. On the same day, the Design-Builder selected buried riprap per HEC-23 as its scour countermeasure (Section 4.3), which is the Design-Builder's design choice under TR 2.30.5.6.

The July statements are consistent with one another and with the Contract. The July 1, 2025 minutes state that a "low" classification "still requires the limits to be determined," and the July 15, 2025 minutes state that the contract classification will be followed (Section 4.3). Read together, they state that the lateral migration classification is "low" and that the scour analysis obligation under TR 2.30.5.6 remains. WSDOT's engagement with the scour analysis between February and July 2025 was review of the Design-Builder's TR 2.30.5.6 obligation. It was not a change to the Table 2.30-B classification, which was never at issue.

The Design-Builder's own presentation is consistent with WSDOT's position and is internally inconsistent with the position the Design-Builder now advances. The January 16, 2026 presentation states that the design "was completed before we received guidance to ignore lateral migration" (Section 4.4), which places the Design-Builder's lateral migration design ahead of the guidance the Design-Builder now characterizes as direction. The same presentation states that lateral migration "did not impact depth of sediment in tunnel" (Section 4.4), which is inconsistent with the later assertion in Skanska LTR 384 that lateral migration extended scour through the full width and depth of the tunnel.

The presentation undermines the direction theory. The only guidance on lateral migration the Design-Builder points to is guidance to disregard it. Its Engineer of Record states the wingwalls and headwall were designed "before we received guidance to ignore lateral migration" (Section 4.4). Guidance to disregard lateral migration is the opposite of a directive to design for it. The contrast Skanska itself draws confirms the design was the Design-Builder's own. At the Sammamish River, classified "not low," the Design-Builder "fought so hard to not include" lateral migration. At Juanita Creek, classified "low," its Engineer of Record designed for it anyway. A Design-Builder that resisted lateral migration at the "not low" crossing did not need to be directed to design for it at the "low" one.

The source of the guidance to ignore lateral migration is immaterial, because WSDOT did not originate the design. Asked by Skanska to say how WSDOT influenced the design, the Engineer of Record did not say WSDOT directed it. It said the design "may have been different if received guidance on lateral migration sooner" (Section 4.4), conceding that no guidance arrived in time to shape it. The Engineer of Record's acknowledgment that the treatment "did impact wingwall design" describes the effect of the Design-Builder's own scour assumption, not a change WSDOT made. The "significant effort" a later revision would have taken is the cost of revising a design the Design-Builder had already chosen.

7.7 Consistency with the Sammamish River crossing

The Design-Builder contends that WSDOT's position here is inconsistent with its position at the Sammamish River crossing, where WSDOT applied a "not low" lateral migration designation. There is no inconsistency. At both crossings WSDOT applies the contract classification as written. The Contract designates the Sammamish River crossing as "not low," and WSDOT applied that designation. More specifically, the Contract states that the Sammamish River "not low" determination "shall apply to the new structures within the river flow limits defined by the 500-year flood elevation." That is an added mandate, particular to Sammamish, that WSDOT enforced. Its absence at Juanita Creek removes only that Sammamish-specific add-on. It does not remove the default scour analysis obligation under TR 2.30.5.6 or the BDM 8.1.10 total scour standard, which apply at every crossing. The Contract designates Juanita Creek as "low" in Table 2.30-B, and the Design-Builder's own scour analysis under TR 2.30.5.6 accounted for lateral migration at the structure. The two crossings carry different contract classifications. WSDOT enforced the Contract as written at each.

7.8 The asserted cost and schedule impacts are unsupported

The asserted entitlement has no contractual basis for the reasons above, which makes the amount moot. WSDOT notes three further points for the record. First, the lateral migration comments were resolved on July 28, 2025, and the design was Released for Construction on December 31, 2025. The Design-Builder first sought an Owner-Initiated Change for this work through Skanska LTR 337 on January 30, 2026, approximately six months after the comments were resolved and after the costs were committed. The record contains no contemporaneous notice that the Design-Builder regarded the lateral migration work as a WSDOT-directed change for which it would seek payment. Second, GP 1-04.5 provides that the Design-Builder's supplemental Written Statement shall include "an analysis of the progress schedule showing the schedule change or disruption" where the Design-Builder asserts a schedule change. No such analysis has been provided in Skanska LTR 384 or Skanska LTR 417. Third, Skanska LTR 417 introduces cost elements that were not in the supplemental Written Statement, including a stream realignment cost element. WSDOT understands this matter to be confined to the circumstances and bases set out in Skanska LTR 384, the supplemental Written Statement. WSDOT addresses the amount only to the extent supportable on that record and reserves all positions on quantum.

The structural record also bears on the magnitude of the asserted cost. The wingwall foundation depth is governed by the retained height and global stability, not by scour. The Final Hydraulic Design calculated total scour of 0.65 to 1.16 feet against a 3-foot minimum scour depth, and the plans bear out that this scour does not control the foundation. On the West Portal the wingwall embedment is identical across the preliminary, final, and Released for Construction plans, even though the bottom-of-scour elevation was raised approximately seven feet at the Released for Construction stage. On the East Portal the bottom-of-scour line did not move between the preliminary and final plans, and the preliminary wingwall toe already sat 17 to 24 feet below it, against a 2-foot requirement. The treatment of lateral migration did not drive the depth of the foundation. The asserted cost is not attributable to a scour-depth increase, which the plans do not show.

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WSDOT's position is as follows.

1. The Contract assigned the scour analysis at Juanita Creek to the Design-Builder under TR 2.30.5.6. The Design-Builder's own analysis found the lateral migration risk "low to moderate" and the data insufficient to exclude it, and the Design-Builder made the conservative engineering judgment to assume lateral migration and design the wingwalls for full scour depth. That judgment was the Design-Builder's own, as its Final Hydraulic Design and its June 13, 2025 email confirm.

2. The Table 2.30-B "low" classification, the TR 2.30.5.6 scour analysis obligation, and the BDM 8.1.10 total scour standard operate together. A "low" classification does not remove the obligation to analyze and design for lateral migration.

3. WSDOT's review comments did not amend the Contract or direct a change. GP 1-02.1 provides that comments on Design Documents do not alter the Contract or relieve the Design-Builder of design responsibility, and GP 1-04.4(1) requires WSDOT to authorize and require a change. Authority to direct the Design-Builder rests with the WSDOT Engineer under GP 1-05.1, and no authorized direction issued. When WSDOT completed its review on July 28, 2025, it confirmed that the "low" classification "shall be followed, otherwise need a DBIC." The record contains no directive to depart from the Contract.

4. The Interpretive Engineering Decision was properly issued under GP 1-03.5, which provides that no Interpretive Engineering Decision forms the basis for a price or time increase and that the Design-Builder bears the burden of proving WSDOT's interpretation incorrect or unreasonable.

5. The Design-Builder is not entitled to an Owner-Initiated Change. The design is the Design-Builder's own, and its cost is within the Contract Price under GP 1-02.1 and GP 1-04.1.

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WSDOT respectfully requests that the Board find and recommend as follows.

1. That WSDOT's review comments and Task Force discussions on the Juanita Creek lateral migration design were design review of the Design-Builder's Design Documents and did not amend the Contract, did not relieve the Design-Builder of its design responsibility, and did not constitute a WSDOT-Initiated Change.

2. That the scour analysis at Juanita Creek was the Design-Builder's obligation under TR 2.30.5.6, that the Design-Builder's decision to assume lateral migration and design the wingwalls for full scour depth was its own engineering judgment, and that the Table 2.30-B "low" classification did not remove the scour analysis obligation.

3. That the Design-Builder is not entitled to an increase in the Contract Price or an extension of the Contract Time on Protest 019.

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Attachment	Description
A	WSDOT SL No. 9727-280, Interpretive Engineering Decision (February 24, 2026)
B	Skanska LTR 372, Notice of Protest 019 (March 10, 2026)
C	Skanska LTR 384, Supplemental Written Statement (March 24, 2026)
D	WSDOT SL No. 9727-326, Written Determination (April 14, 2026)
E	Skanska LTR 417, Notice of Dispute (April 28, 2026)
F	Cited contract provisions: GP 1-02.1, GP 1-03.5, GP 1-03.7, GP 1-04.1, GP 1-04.4, GP 1-04.5, GP 1-05.1, TR 2.13.2.1, TR 2.13.4, TR 2.30.5.2.1, Table 2.30-B, TR 2.30.5.6
G	WSDOT Bridge Design Manual Section 8.1.10, Scour of Retaining Walls
J	June 13 to July 25, 2025 email thread on lateral migration methodology
K	Fish Passage Task Force minutes, July 1 and July 15, 2025
L	Design-Builder Sediment Depth Discussion presentation (January 16, 2026)
N	Design submittals, consolidated by submittal across the preliminary, final, and Released for Construction versions, each with the plans or report, the WSDOT review comment form, and supporting items. Former Attachments H, I, and M are folded in here.

Appendix N is organized as follows.

Item	Description
N1	Juanita Creek Preliminary Hydraulic Design Report (BY-CRE-00858) and its review comment form
N2	Juanita Creek Final Hydraulic Design, Section 7 Final Scour Analysis, Section 8 Scour Countermeasures, and Appendix O Lateral Migration Rapid Assessment, with the FHD review comment form including Comment 196 and the July 28, 2025 comment closure email
N3	East Portal wall structures: preliminary plans (BY-CRE-02210) and review comment form, final plans (BY-CRE-03543) and dispositioned comment form, Released for Construction plans, and the wall elevation progression
N4	West Portal wall structures: preliminary plans (BY-CRE-02327) and review comment form, final plans (BY-CRE-03550) and dispositioned comment form, Released for Construction plans, and the wall elevation progression

The RCSR comments were design review feedback, not Owner-Initiated direction.

Comment 196 (the critical comment Skanska cites) is WSDOT telling AECOM that their own technical evidence supports a "NOT low" conclusion. This is design review, not an OIC. The IED characterization of SL 9727-280 is defensible.

New arguments in LTR 372 (IED characterization, WAC 162-08-017, Section 1-02.1 shield, P003 consistency) do not change this conclusion. Each fails on independent grounds analyzed in Section III.

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WSDOT's evaluation addresses three questions:

1. Did WSDOT direct a change, or did WSDOT point out what the Design-Builder's analysis showed?
2. Is there a distinction between BDM 8.1.10 (retaining wall scour) and Table 2.30-B (fish passage lateral migration)?
3. What procedural and contractual defenses apply?

Finding: The Design-Builder's own analysis supported "NOT low" conditions. WSDOT reviewers pointed this out. The IED is properly issued. No OIC is warranted. Protest should be denied.

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A. Table 2.30-B and Section 2.30.5.2.1

Table 2.30-B designates Juanita Creek (I-405 MP 21.94) lateral migration (structural) as "low." This designation has not been overridden.

Section 2.30.5.2.1 establishes that Table 2.30-B designations "shall apply" and takes precedence. WSDOT's position in both P003 (Sammamish) and P019 (Juanita) enforces the contract as written. The Table 2.30-B designation stands.

B. BDM 8.1.10: Scour of Retaining Walls (Separate Mandatory Standard)

BDM Section 8.1.10 states:

"Total Scour includes the amount of streambed vertical elevation drop at a given location due to the removal of streambed material caused by flowing water and the effects of lateral migration."

The BDM provides three figures:

• Figure 8.1.10-1: Scour without Lateral Migration
• Figure 8.1.10-2: Scour WITH Lateral Migration (cited in Package 9 Comment 4)
• Figure 8.1.10-3: Scour with Lateral Migration and Scour Countermeasures

This is a Mandatory Standard per RFP Section 2.13.4. It applies to ALL retaining walls near water, regardless of the Table 2.30-B fish passage classification. BDM 8.1.10 compliance is the Design-Builder's responsibility.

Both requirements coexist:

Requirement	Source	Applies To	Classification
Fish Passage Lateral Migration	Table 2.30-B	Fish passage structures	"Low" at Juanita Creek
Retaining Wall Scour	BDM Section 8.1.10	Wingwalls, headwalls	Separate mandatory standard

Figure selection is driven by site-specific scour analysis, not Table 2.30-B. The hydraulic engineer performs the scour analysis per Section 2.30.5.6, determines whether lateral migration is a factor based on site conditions (erodible soils, channel migration potential, geomorphic data), and selects the appropriate figure. AECOM's own FHD Section 7.1 found "geotechnical data available at this time are not sufficient to exclude the risk of lateral migration." That finding pointed to Figure 8.1.10-2. The figure selection followed from the site data, not from WSDOT overriding Table 2.30-B.

V2 Determination Letter Decision: BDM 8.1.10 is reserved for DRB and does not appear in SL 9727-280. The determination letter relies on (1) RCSR comments were design review with discretion (Comment 196) and (2) Section 2.30.5.6 required the scour analysis (contractual obligation). BDM 8.1.10 adds a third defense line (existing Mandatory Standard) that requires engineering support to deploy effectively. See Section VII.A for deployment strategy.

C. Section 1-02.1: WSDOT Comment Shield

Section 1-02.1, paragraph 4:

"Notwithstanding anything in the Contract Documents to the contrary, no field explanations or interpretations provided by WSDOT at any meetings, and no comments by WSDOT on Design Documents or Released for Construction (RFC) Documents, shall be deemed, construed, or interpreted to (a) amend, supersede, or alter the terms, requirements, limitations, or meaning of any Contract Document or (b) release or relieve the Design-Builder from full responsibility for the design of the Project in accordance with the Contract Documents. (However, Written Interpretive Engineering Decisions from WSDOT pursuant to Section 1-03.5 may be relied upon to provide information, clarifications and interpretations of ambiguous or uncertain design requirements set forth in the Contract Documents.)"

The shield is absolute for comments. "No comments" means all comments. No tone exception. No distinction between "suggestive" and "directive" comments. RCSR comments on the FHD are exactly "comments by WSDOT on Design Documents." Section 1-02.1 applies directly.

The IED parenthetical carves out one exception: IEDs "may be relied upon." SL 9727-280 is an IED. But the IED itself denies entitlement. Reliance on SL 280 supports WSDOT's position, not Skanska's. See Section III.D for full rebuttal of the shield argument.

D. Section 1-03.5: IED Authority, Entitlement Bar, Burden-Shifting

"The Design-Builder may, from time-to-time, request in writing that WSDOT provide information, clarifications, and interpretations of ambiguous or uncertain design requirements set forth in the Contract Documents (an Interpretive Engineering Decision). WSDOT may issue a Written approval of the Design-Builder's proposed Interpretive Engineering Decision (if any), may issue its own Interpretive Engineering Decision or may disapprove any Interpretive Engineering Decision the Design-Builder proposes."

Key operative phrases:

• "may issue its own Interpretive Engineering Decision" -- WSDOT is expressly authorized to issue its own IED. No DB request prerequisite.
• "no Interpretive Engineering Decision by WSDOT shall form the basis for an increase in the Contract Price or extension of the Contract Time, unless WSDOT expressly provides otherwise in writing" -- Entitlement bar applies regardless of who initiated the IED.
• "the Design-Builder shall bear the burden of proving that WSDOT's interpretation is incorrect or unreasonable" -- Burden-shifting favors WSDOT.

E. GP 1-04.4(1): OIC Requires WSDOT Directive

"WSDOT reserves the right to authorize and require changes in the Work within the general scope of the Contract as provided herein."

WSDOT did not authorize or require a change. Design review comments do not constitute authorization of changes. The RCSR process is a design review mechanism. Comments provide feedback. They are not directives.

F. GP 1-04.5: Protest Procedure and Timeliness

Section 1-04.5 establishes deadlines for protests: 14 calendar days after Written Determination.

LTR 372 was filed March 10, 2026, protesting SL 9727-280 (February 24, 2026). The protest is timely as to SL 280 (14 calendar days).

However, the RCSR comments were issued approximately February 2025. The Design-Builder proceeded from February 2025 through RFC release (December 2025) without protesting the comments. Approximately 10-11 months. If the DB believed the comments exceeded contract requirements, GP 1-04.5 required timely protest. The DB's failure to timely protest the comments is a procedural defense.

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A. Comment 196 (DJS) -- The Critical Comment

"a) Could you make your conclusion clear and complete based on the info you have, 2) Pleased the term 'NOT low' is used. Based on what I read, it seems like this should be your summary. 'Based on the available geologic and geomorphic understanding described in section 2, the risk of lateral migration is NOT low. The existing sediments/soils in the bed and banks are considered erodible. Beavers/beavers dams are present in the watershed. It is possible that the channel could shift or change. We were not able to determine the amount the channel has changed historically.' if this is not correct, please revise"

Why this destroys Skanska's argument:

1. "Based on what I read" -- DJS is summarizing what AECOM's analysis found
2. "it seems like this should be your summary" -- DJS is suggesting how to express AECOM's own findings
3. "if this is not correct, please revise" -- DJS gives AECOM discretion to disagree

This is not direction. This is design review telling the designer their conclusion does not match their evidence.

B. Comment 41 (G.Ng) -- Retaining Wall Connection

"...Bolstering this section will better support the retaining wall designs."

G.Ng explicitly connects the lateral migration analysis to retaining wall design (BDM 8.1.10), not fish passage classification (Table 2.30-B).

C. Package 9 Structures Comments (Comments 3, 4)

Comment 3 (HQH):

"See BDM 8.1.10 Scour of Retaining Walls. These wing walls (both 3 & 4) are parallel to the stream alignment and are subject to total scour along the entire length of the wall. Please confirm bottom of wall is 2 feet below total scour at check flood elevation; including lateral migration (structural)."

Comment 4 (HQH):

"BDM 8.1.10 Scour of Retaining Walls - The foundation for all walls constructed along rivers and streams shall be evaluated during design by the Hydraulics Engineer for total scour... Also see Figure 8.1.10-2"

Both comments explicitly cite BDM 8.1.10, not Table 2.30-B. Comment 4 cites Figure 8.1.10-2 (Scour WITH Lateral Migration) because AECOM's own analysis found conditions (erodible soils, beaver activity, insufficient data to exclude lateral migration) that pointed to that figure. The obligation to evaluate total scour for retaining walls is mandatory per BDM 8.1.10. The specific figure selection follows from the site-specific scour analysis, not from a blanket requirement.

D. 225-Comment Language Pattern

Full RCSR analysis (Package 8: 202 comments, Package 9: 23 comments). See research/Package_8_RCSR_Full_Analysis.md and research/Package_9_RCSR_Full_Analysis.md.

Combined findings:

• Zero comments using directive language ("WSDOT directs," "you shall," "the Design-Builder is required to")
• Zero comments referencing Table 2.30-B lateral migration classification
• 54 "Please..." requests
• 52 questions ("?")
• 28 "Consider/Suggest/Recommend" instances
• All "shall" instances quote existing BDM/code standards

Neither RCSR package contains direction to override Table 2.30-B. The RCSR process was design review.

E. Additional Supporting Comments

Comment 2 (HQH, Package 9): Labeled "Preference." Questions why the wingwall extends parallel to the stream and suggests an angled alternative that would "stay on right of way, reduce depth and length of walls, reduce disturbance/impacts." WSDOT actually suggested a design that would have AVOIDED the lateral migration scour concern. The Design-Builder chose the parallel orientation that created the problem.

Comment 134 (SMB, Package 8): Requests justification for assuming channel bends will not migrate to the walls and discusses bend scour in the retaining wall total scour computation. Connects lateral migration analysis directly to retaining wall design (BDM 8.1.10).

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Each subsection maps to a row in P019_Response_Matrix.md.

A. IED Characterization Is Procedurally Improper (LTR372-0)

Skanska argues: SL 9727-280 does not meet Section 1-03.5 requirements because (a) it was not requested by the DB and (b) WSDOT simultaneously claims "no ambiguity" while issuing an IED, which presupposes ambiguity.

Counter-analysis:

1. Section 1-03.5 expressly permits WSDOT-initiated IEDs. "WSDOT... may issue its own Interpretive Engineering Decision." The provision does not require a DB request as a prerequisite. The sentence structure treats DB-requested IEDs and WSDOT-initiated IEDs as parallel authorities.

2. The "ambiguity trap" fails. IEDs can interpret clear provisions. The scope clause ("ambiguous or uncertain design requirements") describes what IEDs MAY address, not a limitation. Interpreting a design requirement does not concede ambiguity. The IED confirms what the contract requires.

3. The substance controls, not the label. Even if the "IED" label were questioned, SL 9727-280 is also a Written Determination under GP 1-04.5 responding to LTR 337. The determination's substance stands regardless of heading.

4. Precedent and pattern.

   • SL 116 (Sammamish River, P003): WSDOT issued an IED on lateral migration. Skanska did not challenge SL 116's IED characterization. SL 116 is the format precedent for SL 280 (per the Evelyn email).
   • SL 9727-209 (Waterproofing, P010): WSDOT issued an IED on waterproofing requirements at Brickyard Station. Skanska raised the same "IEDs must be DB-requested" argument in LTR 287/LTR 301. WSDOT's P010 position: Section 1-03.5 "expressly authorizes" WSDOT to issue its own IED. The claim has no merit.
   • Implication: This is now a pattern. Skanska has recycled the "unsolicited IED" argument across at least P010 and P019. WSDOT's answer is the same both times because the contract text is clear. At DRB, the repeated use of a previously rejected argument may weaken Skanska's credibility on this point. The primary authority remains the Section 1-03.5 text itself ("may issue its own"). The precedent pattern is supporting context, not a standalone defense.

5. Section 1-02.1 interaction (favorable). By characterizing SL 280 as an IED, WSDOT brings it within the only class of documents the DB MAY rely upon. But the IED itself denies entitlement. Reliance on it does not help Skanska. Conversely, if SL 280 is NOT an IED, then Section 1-02.1 prevents the DB from relying on it to alter contract requirements. Either way, the DB loses.

Risk assessment:

Risk	Likelihood	Impact	Mitigation
DRB accepts "ambiguity trap"	LOW	MEDIUM	SL 280 is also a GP 1-04.5 determination
DRB finds WSDOT lacked authority	LOW	HIGH	"May issue its own" is express authority
Skanska argues IED undermines 1-02.1	MEDIUM	LOW	IED denies entitlement

B. WAC 162-08-017 and "Shall" Language (LTR372-1)

Skanska argues: WAC 162-08-017 establishes "shall" = mandatory command under WA law. RCSR comments using "shall" are therefore directives.

Counter-analysis (three independent reasons this fails):

1. Wrong scope. WAC 162-08-017(1) governs "this chapter" (Chapter 162-08, Human Rights Commission Practice and Procedure). It does not govern WSDOT contracts.

2. Statutory construction vs. contract interpretation. Even the general principle (RCW 1.12, "shall" is mandatory) is a rule of statutory construction. RCW 1.12 by its own terms applies to "the construction of statutes." Washington courts interpret contracts under contract-interpretation principles (plain language, objective intent), not canons of statutory construction.

3. Even if applied, who does "shall" bind? The "shall" instances in Package 9 Comments 3 and 4 quote BDM 8.1.10 verbatim. The BDM commands the designer, not WSDOT commanding the Design-Builder. The reviewer cited an existing standard. No new "shall" requirement was created.

Comment 196 uses no "shall" language at all. It says "seems like," "should be," and "please revise." These are the opposite of mandatory commands.

Assessment: WEAK. The argument fails at every level of analysis.

C. Comment 196 as Direction (LTR372-2)

Skanska argues: Comment 196 explicitly stated "NOT low." This is direction, not review.

Counter-analysis:

Design-Builder Argument	Why It Fails
WSDOT directed "NOT low" treatment	Comment 196 says "based on what I read, it seems like this should be your summary" and "if this is not correct, please revise." DJS was summarizing what AECOM's own analysis found.
RCSR comments overrode Table 2.30-B	No RCSR comment references Table 2.30-B lateral migration. All cite BDM. Comment 41 explicitly connects to "retaining wall designs."
Comments used mandatory language	Comment 196 uses no "shall." BDM requirements are mandatory, but compliance is the Design-Builder's responsibility.
WSDOT created new requirements	The Design-Builder's own analysis found conditions warranting "NOT low" treatment. WSDOT reviewers identified this. The design approach came from AECOM's findings, not WSDOT direction.

Fatal flaw: AECOM's own FHD found erodible soils, beaver activity, and unknown historical channel changes. The evidence supported "NOT low" conditions. The reviewer summarized what AECOM's analysis showed. The Design-Builder cannot claim that designing for conditions their own analysis identified is extra work.

D. Section 1-02.1 Does Not Shield "Directive" Comments (LTR372-3)

Skanska argues: Section 1-02.1 applies to "comments" but not to "directions." If a comment crosses the line into a directive, the shield does not apply.

Counter-analysis:

1. No tone exception in the text. Section 1-02.1 says "no comments." It does not say "non-directive comments" or "suggestive comments." Any attempt to subdivide "comments" into "suggestive" and "directive" categories reads a distinction into the contract that does not exist.

2. The only carved-out category is IEDs. If WSDOT intended to exclude "directive" comments from the shield, it would have said so. The only exception is "Written Interpretive Engineering Decisions."

3. Even if a comment were "directive," timeliness applies. The proper remedy under the contract is GP 1-04.5 (protest within 14 days). Skanska did not protest the RCSR comments when issued. The protest is untimely as to the comments themselves.

Assessment: Section 1-02.1 is WSDOT's strongest contractual shield. It applies directly to RCSR comments. The IED exception does not undermine it because the IED itself denies entitlement.

E. Practical Impossibility of Discretion (LTR372-4)

Skanska argues: "Full discretion" was not available in practice. RCSR gating prevented RFC without addressing lateral migration. The DB had no real choice.

Counter-analysis:

1. Comment 196 gave express discretion. "If this is not correct, please revise." AECOM could have responded with supporting rationale for disagreement. Standard RCSR process allows technical dialogue.

2. AECOM's own analysis agreed. FHD Section 7.1 found insufficient data to exclude lateral migration risk. Appendix O found erodible soils. AECOM did not exercise discretion to disagree because their own evidence agreed with the reviewer.

3. AECOM's design preceded any guidance. Slides 16-17 of the AECOM presentation: "The final design of the wingwalls and headwall was completed before we received guidance to ignore lateral migration." The design incorporating lateral migration was AECOM's original design.

4. Contractual remedies existed. If the DB believed RCSR comments exceeded contract requirements, it could have (a) protested under GP 1-04.5 within 14 calendar days, (b) submitted a DBIC under GP 1-04.4(2), or (c) responded to the comment with technical rationale for disagreement. The DB did none of these.

5. July 28, 2025 comment closure is devastating. SL 9727-280 states: "July 28, 2025 -- WSDOT Comments on lateral migration were closed consistent with Contract terms: lateral migration at Juanita Creek is defined as low and shall be followed, otherwise need a DBIC from Design Builder." WSDOT explicitly confirmed "low" when closing the comments and told the DB to file a DBIC if it disagreed. The DB never filed a DBIC. If the DB's designer continued with "NOT low" treatment after this closure, that was the DB's own design choice.

F. Timeline Causation (LTR372-5)

Skanska argues: Timeline and design chain establish cause-and-effect. WSDOT comments caused the lateral migration design.

Counter-analysis:

The design incorporating lateral migration preceded any WSDOT guidance. AECOM's Sediment Depth Discussion presentation (January 16, 2026, Slides 16-17) states: "The final design of the wingwalls and headwall was completed before we received guidance to ignore lateral migration."

Skanska's own internal email to AECOM asked: "Why was lateral migration included here? We fought so hard to not include lateral migration at the Sammamish River but seemed to accept it here. Please explain." This demonstrates:

• Skanska did not understand why AECOM included lateral migration
• Skanska considered the decision to be AECOM's, not WSDOT's
• Skanska's own email characterizes it as AECOM "accept[ing]" lateral migration, not WSDOT directing it

AECOM's response referenced the FHD being from "before we received guidance to ignore lateral migration." If this guidance came from Skanska (directing AECOM to follow Table 2.30-B "low"), then Skanska directed its own designer to disregard site conditions that AECOM's professional analysis had identified. See Section IV.D for full evidence analysis.

G. P003/P019 Consistency (LTR372-6)

Skanska argues: WSDOT enforced "not low" at Sammamish (P003) but denies directing "not low" at Juanita (P019). This is inconsistent.

Counter-analysis:

Factor	P003 (Sammamish)	P019 (Juanita)
Contract designation	"Not low" (Section 2.30.5.2.1 "shall apply")	"Low" (Table 2.30-B)
What DB wanted	LESS than contract required (reduce to "low")	Did MORE than Table 2.30-B (designed for "NOT low")
WSDOT's action	Enforced the contract designation (SL 116 IED)	Reviewed the design. Pointed out what DB's own analysis showed.
Direction of dispute	DB wanted to REDUCE below contract	DB EXCEEDED Table 2.30-B based on own analysis
Core defense	Contract says "shall apply" -- mandatory	RCSR = design review, not direction. BDM 8.1.10 = separate standard.

The flaw in Skanska's framing: It conflates two different WSDOT functions. Enforcing a contract requirement (P003) is not the same as reviewing a design submission (P019). WSDOT can enforce a contract designation at one crossing and review a design submission at another without inconsistency.

The unifying principle: Contract requirements are the floor. The DB cannot go below the floor (Sammamish). When the DB's own analysis identifies conditions above the floor, that is the DB's professional responsibility (Juanita). In neither case did WSDOT change the contract.

BDM 8.1.10 adds a second distinction. At Juanita, there is an independent basis: BDM 8.1.10 applies to retaining walls regardless of the Table 2.30-B fish passage classification. This basis does not exist at Sammamish (different structure type).

See Section VII.D for DRB coordination warnings and RCSR characterization caution.

H. Expanded Scope and Buried Riprap (LTR372-7, LTR372-8)

Skanska argues: Scope growth is not limited to footings. Wingwalls, headwalls, beams, micropiles all affected. Buried riprap protects the existing MSE wall.

Counter-analysis: WSDOT does not dispute that the DB incurred costs. The question is whether those costs result from WSDOT direction (they do not) or from the DB's own design analysis and compliance with mandatory standards. See Section VI for full entitlement analysis.

Buried riprap (LTR372-8): Reserved for SKA-0297 (Juanita Creek Property Rights). The scour countermeasure obligation derives from Section 2.30.5.6 ("shall locate, design and construct any required scour countermeasures"). AECOM's own presentation (Slides 18-20) notes the buried riprap is "not connecting to or protecting the new structure." It protects "an existing MSE wall downstream of the structure."

I. "Constructive Direction" Theory (LTR384-1) -- NEW

Skanska argues (LTR 384 Section 4): WSDOT's RCSR comments constituted "constructive direction" based on four factors: (a) mandatory "shall" language, (b) incorporation of lateral migration required for comment resolution and RFC, (c) no practical discretion under the original Contract framework, and (d) increased scope and cost. Section 1-02.1 cannot retroactively disclaim responsibility.

Counter-analysis:

1. The contract does not recognize "constructive direction." GP 1-04.4(1) defines OICs: WSDOT "reserves the right to authorize and require changes." This requires affirmative WSDOT action. The word "authorize" is intentional. RCSR comments do not authorize changes. GP 1-02.1 confirms this by shielding all comments from amending contract requirements. There is no middle category of comments that are "constructive" enough to bypass this framework.

2. Each factor fails independently:

   • (a) "Shall" language: all instances quote BDM 8.1.10 verbatim. The BDM commands the designer, not WSDOT commanding the DB. Comment 196 uses no "shall" at all.
   • (b) Comment resolution as RFC prerequisite: this is standard RCSR process for ALL comments, not just these. If comment resolution equals direction, every RCSR comment on any project would be a directive.
   • (c) Practical discretion: Comment 196 says "if this is not correct, please revise." DB had GP 1-04.5 protest (14 days) and GP 1-04.4(2) DBIC. DB used neither. TFM meeting ACTION items were assigned to "Design team," not imposed by WSDOT.
   • (d) Increased scope/cost: cost does not establish entitlement. The cost resulted from AECOM's own analysis finding conditions supporting lateral migration treatment and from DB's parallel wingwall orientation choice.

3. Section 1-02.1 is not retroactive. It was part of the original Contract. It applies at the time the comments were made, not "after the fact."

Risk assessment: This is Skanska's strongest new argument. It may resonate at DRB because it reframes the issue from "were these comments directive?" to "did the cumulative effect constitute direction?" WSDOT's defense: GP 1-02.1 and GP 1-04.4(1) define the framework. The "constructive" theory asks the DRB to create a new category of direction that the Contract does not recognize. The existing contractual remedies (protest, DBIC) were available and not used.

I-2. TFM Meeting Minutes Confirm "Scour at Wing Walls," Not Lateral Migration Classification

The entire methodology discussion from January through July 2025 was tracked under TFM agenda item "Scour at Wing Walls" (item 2.4 in Meeting #27, item 2.5 in subsequent meetings). The item description is "Depth requirements for Scour at wing walls." Meeting #27 (January 14, 2025) laid out BDM Figures 8.1.10-1 (Scour without Lateral Migration) and 8.1.10-2 (Scour WITH Lateral Migration) and assigned "ACTION: design team to review and apply to wing walls at fish passages."

This is significant because it shows WSDOT framed the discussion as a BDM retaining wall scour requirement from the outset, not as a lateral migration reclassification. The subsequent methodology discussions (valley width, 500-year extents, etc.) were all under this same "Scour at Wing Walls" item. When Meeting #30 (February 25) noted "No reduction of wing wall depth at Juanita," it was reporting a result of the BDM scour analysis, not WSDOT refusing to allow shallower wingwalls because of the lateral migration classification.

This factual record supports the determination letter's argument that "Table 2.30-B classifies the lateral migration risk level. BDM 8.1.10 establishes retaining wall scour design requirements. These are complementary requirements, not an inconsistency."

Gabe Ng April 14, 2026 clarification of TFM #39 July 1 language. The July 1 TFM #39 minutes state "WSDOT notes that lateral migration defined as low in Chapter 2 still requires the limits to be determined." Gabe Ng confirmed the context by email on April 14, 2026: "what I recall repeating to the DBer was 'low' does not equate to zero. DBer still needs to understand if the lateral migration limits will impact the walls? They completed this simple analysis to my satisfaction in the email, as noted and should be documented in FHD as I noted." This confirms two things: (1) the July 1 TFM language was consistent with Gabe's contemporaneous position that "low" does not eliminate the Design-Builder's TR 2.30.5.6 scour analysis obligation, and (2) the Design-Builder completed a satisfactory analysis in the June 18, 2025 email exchange proposing 46 ft valley width, and Gabe approved it same-day. The July 1 TFM was not a reversal, not a new requirement, and not a directive. Source: references/Letters/RE_Juanita_Creek_Lateral_Migration_2026-04-14_Gabe_Ng_Response.eml.

I-3. Five-Meeting Gap: Scour at Wing Walls Drops Off TFM Agenda (April-June 2025)

AECOM's narrative claims continuous WSDOT pressure on lateral migration methodology from February through July 2025. The TFM minutes tell a different story. The "Scour at Wing Walls" agenda item appears in Meetings #27 (Jan 14), #28 (Jan 28), #29 (Feb 11), and #30 (Feb 25). It then disappears entirely from the agenda for five consecutive meetings: #33 (Apr 8), #34 (Apr 22), #35 (May 6), #36 (May 20), and #37 (Jun 3). During this period, Juanita Creek was discussed only for morphology changes, maintenance access, planting, and permitting. No scour, no lateral migration, no wing wall depth.

The scour discussion reappears at Meeting #38 (Jun 17) when the design team brings the lateral migration extents methodology back for concurrence. This gap undercuts the "continuous WSDOT pressure" narrative. For over two months, the topic was not on the agenda. When it returned, it was because the design team brought it back, not because WSDOT raised it.

J. Methodology Rejection Narrative (LTR384-2) -- NEW

AECOM argues (points 2-7): WSDOT rejected multiple AECOM methodologies for estimating lateral migration without providing alternatives. Valley width of 60 ft was rejected. 500-year flood extents were rejected. Stream power vs erodibility was considered but not adopted.

Counter-analysis:

1. Gabe Ng April 14, 2026 email confirms no methodology was rejected. The named WSDOT reviewer does not recognize AECOM's "rejection" characterization: "The onerous should be on DBer to support their claims of 'rejection' by WSDOT. I'm unclear what they are asking or claiming in that sentence. I'd ask for expanded clarification and documentation." Gabe provided the complete June 13 - July 25, 2025 email thread. The thread records no rejection of any methodology the Design-Builder proposed. Source: references/Letters/RE_Juanita_Creek_Lateral_Migration_2026-04-14_Gabe_Ng_Response.eml; full thread extract at references/Letters/Gabe_Ng_2025-06-13_to_2025-07-25_Email_Thread.md.

2. The "60 ft valley width rejected" claim is not in the record. The contemporaneous email thread shows the Design-Builder proposed a 46 ft average valley width on June 18, 2025, based on 9 cross sections in the design reference reach. Gabe Ng approved 46 ft same day: "This looks good. Thank you. I agree with your estimate of lateral migration extents and documentation. Please include this information in the final FHD." The figure the Design-Builder submitted and Gabe approved is preserved at references/Letters/Figures/image001.png (cross section labeled "LATERAL MIGRATION WIDTH 46'") and references/Letters/Figures/image002.png (plan view of 9 cross sections). If AECOM's PCN-00153 asserts "60 ft was rejected," that claim refers to no exchange documented in the Gabe Ng thread. Per Gabe's April 14 advice, the burden is on the Design-Builder to identify what it claims was rejected, when, and by whom.

3. Several "rejections" were not WSDOT rejections at all. AECOM itself rejected the stream power vs erodibility approach ("not appropriate at this fish passage, as it is intended for systems with bedrock"). Historical imagery analysis was "unsuccessful" due to site conditions (imagery resolution, tree cover) per AECOM's own June 13 email. These were limitations of AECOM's own investigation, not WSDOT actions.

4. Evaluating proposed methodologies is standard design review. Section 2.30.5.6 assigns the scour analysis obligation to the Design-Builder. When the Design-Builder proposes a methodology, WSDOT evaluates it. Asking a design question is not a rejection, and asking for validation is not direction. The distinction matters: if every review comment that requests validation equals direction, no design review could occur without creating OIC liability.

5. WSDOT accepted the valley width approach when adequately supported. TFM #38 (June 17): "ACTION: Design team to send over the shoulder analysis to WSDOT for concurrence." AECOM sent the over-the-shoulder analysis on June 18, 2025. Gabe approved the same day. This shows WSDOT was reviewing proposals, not blocking progress.

6. AECOM's own email confirms the Design-Builder, not WSDOT, selected the scour countermeasure. June 18, 2025, 10:35 AM (Yacoub Raheem): "Here is the updated section view of the scour prism at the downstream end of the wingwalls (at the MSE wall), looking upstream. We will use this as a guide to design buried riprap following HEC-23 to protect the MSE wall." AECOM chose buried riprap. AECOM chose HEC-23. AECOM designed the extent. See references/Letters/Figures/image005.png for the cross section AECOM used.

7. AECOM's own email undermines the "directed to design for full lateral migration" narrative. June 13, 2025 (Yacoub to Gabe): "The risk of lateral migration may only be low to moderate; however, to be conservative, lateral migration was assumed when conducting scour analysis (it is assumed that thalweg can migrate to wall for new structures)." And: "Regarding the structures, both tunnel and wingwalls are designed for full scour depth. FHD did not include scour countermeasures to be provided on top of that." This is an AECOM conservative design judgment made before any WSDOT methodology guidance. AECOM incorporated lateral migration into their scour analysis as their own professional judgment.

8. TFM meeting minutes confirm collaborative process. TFM #29 (Feb 11): "Design to consider input from WSDOT." TFM #38 (Jun 17): "Design team to send analysis for concurrence." All ACTION items assigned to the Design team. No WSDOT directives.

K. Jason Pang MSE Wall Comment (LTR384-3) -- NEW

AECOM argues (point 6): In April 2025, Jason Pang's structural comment on the West Portal preliminary design "re-triggered" the lateral migration issue for the existing MSE wall, requiring calculation of lateral migration to determine scour potential.

Counter-analysis:

1. The actual Comment #25 is a statement of existing requirements, not a directive. West Portal Preliminary RCSR Comment #25 (XL/JP, BDM 7.1.7): "At the joint between the wingwall and existing MSE wall at both wingwall ends scour requirements for the new and old portion of the MSE apply." This states what BDM 7.1.7 requires. It does not direct the Design-Builder to add lateral migration. The comment says scour requirements "apply." That is a factual statement about the standard, not new direction from WSDOT. The West Portal RCSR has 60 comments, almost entirely drafting, formatting, and verification requests. Zero directive language.

2. Jason Pang's East Portal comments were also verification requests. Preliminary East Portal Comment #13 (JP, BDM 8.1.5D): "Embedment depth of wall fascia could not be verified for compliance. Please provide dimensions of water elevations, scour, thalweg." He could not verify the design and asked for information. His follow-up: "I understand open items with the hydraulic design may lend to scour changes. FHD needs to be finaled and RFCed for structure to be released per 2.28.3.4." Standard structural review sequencing.

3. Scour evaluation for existing walls is a contract requirement. TR 2.13.4 requires existing wall elements "affected by the Work" to "meet the minimum foundation cover requirements or be protected against scour to that level." The existing MSE wall (Wall 2185L-A) is identified in the contract (RFP Section 2.6) as requiring "full or partial replacement to install the fish passage structure." Scour evaluation for this wall is not additional scope.

4. AECOM's own June 13, 2025 email confirms this. "In response to a structural comment from Jason Pang related to protection of the downstream MSE at Juanita Creek, we need to quantify potential extent of lateral migration." AECOM explicitly identifies Pang's comment as the trigger for the quantification effort. But quantifying scour potential for an existing wall affected by the Work is a TR 2.13.4 obligation, not a lateral migration reclassification.

5. RFC Comment #16 (TB/JP) is a question, not a directive. "At the end of wingwall 3 and 4, is the scour depth 10-20ft as shown?" The DB's own response: "The scour line has been reviewed by the hydraulic team." AECOM's own hydraulics team did the review. Final Disposition: "A" (accepted).

6. Complete RCSR closure chain confirms normal design review. The preliminary East Portal Comments #3, #4 (BDM 8.1.10) and #13 (embedment) carried forward with disposition "R" (resolve in next phase). The DB updated its drawings ("09/08/2025: Drawings updated for East Portal final submission"). The final RCSR (39 new comments) does NOT re-raise BDM 8.1.10 scour issues. The final reviewers (same Jason Pang) accepted the updated design. For the West Portal, preliminary Comments #24 and #25 evolved into final Comments #7 and #10 about the MSE wall interface and grading. Both received disposition "T" (transfer to hydraulic design) as of January 2026, with the note "pending completing the hydraulic design." This is standard design sequencing: the structural reviewers deferred to the hydraulic design being finalized. They did not direct lateral migration.

7. Internal email documents the exact closure sequence. Email from Sonia Berriz to Evelyn Pao (filed at Evidence/Juanita_Creek_Comments.msg) provides the closure timeline for the comments Skanska quotes in the protest:

   • Comment responses provided by DB on June 5, 2025
   • Gabe Ng responded June 23, 2025
   • Sonia Berriz closed Gabe's open comment on July 28, 2025
   • Alex Strom closed all remaining quoted comments on October 21, 2025

   Sonia describes this as "a working RCSR form as this package has not come in for RFC. It captures the closure of all of the quoted comments." This confirms the comments were closed through the normal RCSR process. Attachments included Juanita-Creek_RCSR_WSDOT_Backcheck.xlsx and Juanita-Creek_RCSR_Preliminary.xlsx.

8. July 16, 2025 AECOM email confirms the TFM #40 to comment closure sequence. The day after the July 15 TFM meeting (#40), Yacoub Raheem (AECOM) emailed Sonia Berriz with "the Juanita Creek RCSR Forms, including structural forms, with unresolved dispositions, as requested in yesterday's Fish Passage Task Force Meeting" (filed at Evidence/RE_EXTERNAL_Juanita_Creek_RCSR_Forms.msg). This shows the July 15 meeting resulted in AECOM providing the RCSR forms to Sonia for closure. Sonia closed Gabe's comment on July 28. The sequence is: July 15 meeting (confirm "low" classification) -> July 16 AECOM sends forms -> July 28 Sonia closes comments consistent with "low." This is orderly administrative closure, not a reversal.

L. "Reversal" Narrative (LTR384-4) -- NEW

Skanska argues (Section 7) / AECOM argues (point 9): On July 15, 2025, WSDOT reversed its position by stating that since the contract defines lateral migration as low, limits of migration do not need to be determined. On July 28, 2025, WSDOT closed the RCSR comments. This reversal came after the wingwall and headwall design was substantially complete and significant resources had been expended.

Counter-analysis:

1. July 15 did not reverse any prior position. The full TFM #40 minutes show: "Contract defines lateral migration at Juanita Creek as low and will be followed." This confirms what Table 2.30-B always said. The same meeting also assigned: "ACTION: WSDOT to discuss internally direction on lateral migration." If this were a clean reversal, there would be no need for further internal discussion.

2. The July 1 notes (embedded in TFM #40) provide the context. TFM #39 (July 1, 2025): "WSDOT notes that lateral migration defined as low in Chapter 2 still requires the limits to be determined." This is consistent with Section 2.30.5.6 and BDM 8.1.10. "Low" classifies the risk. It does not eliminate the scour analysis obligation. WSDOT was consistently saying: "low" per contract AND limits still need to be determined for retaining wall scour.

3. "Low" does not mean "no analysis needed." Section 2.30.5.6 requires: "The Design-Builder shall perform a scour analysis that includes... the risk of Lateral Migration (Structural)." No carve-out for "low" risk. BDM 8.1.10 requires total scour evaluation for ALL retaining walls, and Total Scour "includes... the effects of lateral migration." These obligations apply regardless of Table 2.30-B classification.

4. No DBIC filed after July 28 closure. SL 9727-280 Section 4: comment closure told the DB "the contract requirement regarding low lateral migration shall be followed" and directed filing a DBIC if it disagreed. The DB did not file a DBIC. Instead, the DB continued with its existing design (which already incorporated lateral migration) and filed LTR 337 six months later seeking $5.4M.

5. The "reversal" characterization assumes WSDOT previously directed "NOT low." WSDOT denies this. Comment 196 summarized what AECOM's own analysis found. Design review is not direction.

M. Tunnel Design Claim -- Internal Contradiction (LTR384-5) -- NEW

Skanska argues (Section 8): "Tunnel Design: Scour extended to full width and depth due to lateral migration, resulting in increased footing depths and tunnel quantities."

Counter-analysis: This directly contradicts AECOM's own prior statement. AECOM Sediment Depth Discussion Presentation, Slide 17 (January 16, 2026, attached to LTR 337): lateral migration "did not impact depth of sediment in tunnel." LTR 384 cannot claim tunnel design was impacted by lateral migration when AECOM's own presentation -- submitted as part of the same protest -- says it was not.

---

Key new persons identified

• Yacoub Raheem (AECOM): Author of June 13 and June 18, 2025 emails to Gabe Ng/Alex Strom proposing lateral migration methodologies.
• Erin Gaffney (Skanska): Followed up on BDM version clarification (January 13, 2025).

Yacoub Raheem Email -- June 13, 2025 (Full Text)

From: Raheem, Yacoub (yacoub.raheem@aecom.com) Sent: Friday, June 13, 2025 12:24 PM To: Alex Strom (astrom@hntb.com); Ng, Gabe (Gabe.Ng@jacobs.com) Cc: Jarosz, Katherine; Cote, Meredith; Gentzler, Seth; Mcneely, Steve; Jones, Curtis (all AECOM) Subject: [EXTERNAL] RE: I405 BY: RSCR Comment Follow Up

Hi Gabe and Alex,

We look forward to speaking with you soon. In case you had a little bit of time before the call, we wanted to send along some bullet points we would like to discuss. In response to a structural comment from Jason Pang related to protection of the downstream MSE at Juanita Creek, we need to quantify potential extent of lateral migration. Up until now, we have found it difficult to develop an exact value for lateral migration, and thus, designed tunnel and wingwalls for full scour depth:

• Dense vegetation and tree cover, poor aerial imagery resolution, make it difficult to delineate features such as the top of bank and stream centerline, and thus it is not possible to define the extents of channel migration based on historical imagery.
• Based on geotechnical information, there are no non-erodible geologic features or cohesive materials that could limit the extents of lateral migration of the stream channel.
• Since this is a new channel, some historical features (e.g. trees or vegetation on the banks) may not be entirely relevant. Also there is no historical imagery upon which to estimate lateral migration of future conditions.
• The risk of lateral migration may only be low to moderate; however, to be conservative, lateral migration was assumed when conducting scour analysis (it is assumed that thalweg can migrate to wall for new structures).
• Regarding the structures, both tunnel and wingwalls are designed for full scour depth. FHD did not include scour countermeasures to be provided on top of that.
• During preliminary design, WSDOT measured the meander belt width to be 30 feet; this was used to size this width of the tunnel during preliminary design. Since then, the tunnel has been widened to 37.8 feet.
• The flood prone width (which is defined as the water surface width at twice the bankfull depth or the width at the 50-year to 100-year flood) can be considered as a proxy for the channel migration zone and the extents of lateral migration. The FPW was calculated as 18.1 ft in the upstream reach and 17 feet in the downstream reach, based on the 100-yr model results.
• We propose that the modeled 500yr extents be considered the extent of lateral migration.

Full email thread obtained April 14, 2026. Gabe Ng provided the complete June 13 - July 25, 2025 thread in response to Zach Archer's April 6 request. Source: references/Letters/RE_Juanita_Creek_Lateral_Migration_2026-04-14_Gabe_Ng_Response.eml. Full extract at references/Letters/Gabe_Ng_2025-06-13_to_2025-07-25_Email_Thread.md. The original email that prompted Yacoub's June 13 message is a Teams meeting invitation from Meredith Cote (AECOM) dated June 11, 2025, scheduling a June 13, 2025 1:30 PM PT "RSCR Comment Follow Up" call. No WSDOT directive initiated the exchange. AECOM initiated the discussion to address the Jason Pang structural comment on MSE wall protection.

Gabe Ng Response -- June 13, 2025 (Same Day)

From: Ng, Gabe (Gabe.Ng@jacobs.com) Sent: Friday, June 13, 2025 1:03 PM To: Raheem, Yacoub; Alex Strom

Thanks Yacoub,

I have similar comments/concerns. One of my added comments is to understand where/how the 30' meander width was estimated; and why the tunnel was additionally widened.

I didn't see any validation to the meander width or valley width in the updated FHD to support the outer limits of what the historic migration limits would be.

Depending on where the walls are located; I believe you could use a countermeasure to mitigate total scour but I have to double check which manual that is in.

Analysis of Gabe's response:

1. Gabe asked for validation, not rejection. Gabe's question is about the basis for AECOM's existing 30 ft meander width estimate. He notes the FHD does not include validation. He does not reject a 60 ft valley width. He does not reject 500-year flood extents. He does not reject stream power. He asks AECOM to show its work.

2. Gabe raises the possibility of countermeasures. "Depending on where the walls are located; I believe you could use a countermeasure to mitigate total scour." This is a design-review observation that mitigation may be available, not a directive to AECOM to add countermeasures. AECOM's subsequent June 18 decision to design buried riprap per HEC-23 was AECOM's own engineering decision.

Yacoub Raheem Proposal -- June 18, 2025, 12:49 AM

Subject: [EXTERNAL] RE: I405 BY: RSCR Comment Follow Up

Hi Gabe and Alex,

We would like to come to a consensus on lateral migration extents for Juanita Creek as soon as possible, since this impacts other disciplines. We performed an updated valley width analysis for Juanita Creek, something we discussed with Gabe several months ago (Alex, I don't think you were on that call). We looked at cross sections in the design reference reach and estimated a conservative average width of 46.0 feet. We propose to use this value for lateral migration extents. This is wider than the 30-foot meander belt width estimated by WSDOT for preliminary design, wider than the proposed tunnel width (37.8 feet), and wider than proposed 500-year extents downstream near the MSE wall.

Here is some additional text we would add to Section 2.7.5. Channel Migration: [proposed text for FHD including reference to 9 cross sections in design reference reach]

The tunnel and wingwalls are designed for full scour depth and do not require scour protection. We propose to use this lateral migration extents to design scour protection for the MSE wall, using the extents to determine how much of the MSE wall will need to be protected.

Gabe Ng Approval -- June 18, 2025, 9:26 AM (Same Day)

From: Ng, Gabe

Yacoub,

This looks good. Thank you. I agree with your estimate of lateral migration extents and documentation. Please include this information in the final FHD.

Yacoub Raheem Scour Countermeasure Commitment -- June 18, 2025, 10:35 AM

Hi Gabe,

Thank you for the quick response! Here is the updated section view of the scour prism at the downstream end of the wingwalls (at the MSE wall), looking upstream. We will use this as a guide to design buried riprap following HEC-23 to protect the MSE wall.

Note that I updated the lateral migration extents figure below to match the one in the spreadsheet (there was a minor difference).

Figures preserved:

• references/Letters/Figures/image001.png -- Cross section labeled "LATERAL MIGRATION WIDTH 46'" with both wingwalls and scour prism (from updated 10:35 AM figure).
• references/Letters/Figures/image002.png -- Plan view of 9 cross sections in design reference reach used to derive the 46 ft average.
• references/Letters/Figures/image005.png -- Scour prism section view at downstream end of wingwalls showing calculated total scour = 1.1 ft. This is the figure AECOM committed to use as guide for buried riprap per HEC-23.

Key conclusions from the full thread:

• No WSDOT rejection of any methodology AECOM proposed.
• Same-day WSDOT approval of 46 ft valley width on June 18, 2025.
• AECOM's own choice to design buried riprap per HEC-23 for MSE wall protection.
• AECOM's own written admission that tunnel and wingwalls were "designed for full scour depth" independent of lateral migration, and that lateral migration was "assumed when conducting scour analysis" as AECOM's own conservative engineering judgment.
• The July 1 TFM #39 language "limits to be determined" was consistent with, not a reversal of, this June 18 exchange.

"WSDOT measured the meander belt width to be 30 feet": Needs verification with Gabe Ng. Did WSDOT measure this, or did WSDOT review AECOM's measurement? The attribution matters.

Admissions against interest (additions to Section VII.C)

From the June 13, 2025 Raheem email:

1. "In response to a structural comment from Jason Pang" -- AECOM explicitly says the lateral migration quantification was triggered by Pang's structural comment about the MSE wall, not by any lateral migration classification change. This is standard structural review (TR 2.13.4 / BDM 8.1.10), not direction to change the lateral migration classification.
2. "lateral migration was assumed when conducting scour analysis" -- AECOM's conservative assumption, their professional judgment. Not WSDOT direction.
3. "no non-erodible geologic features or cohesive materials that could limit the extents" -- AECOM's own geotech data confirms what Comment 196 said. Erodible conditions exist. The reviewer summarized what AECOM's data showed.
4. "both tunnel and wingwalls are designed for full scour depth" -- Already designed this way BEFORE this email. Undercuts LTR 384 Section 8's claim that the tunnel was additionally impacted. Aligns with Slide 17 ("did not impact depth of sediment in tunnel").
5. "We propose that the modeled 500yr extents be considered" -- AECOM is proposing a methodology to WSDOT, not the other way around. WSDOT did not direct the 500-year extents approach.

From the AECOM supplemental narrative:

• AECOM point 1: "AECOM's approach was to use Figure 8.1.10-1 which assumes the width of the scour prism is equal to the extents of the check flood." This confirms AECOM's initial design choice was to use Figure 8.1.10-1 (without lateral migration). The subsequent use of Figure 8.1.10-2 followed from AECOM's own analysis finding conditions that warranted it, not from WSDOT direction.
• AECOM point 9: After July 28 comment closure, "AECOM subsequently selected BDM Figure 8.1.10-1 to estimate a scour prism... This utilizes the 500-year extent and arrives at a width of approximately 38 feet." After the "reversal," AECOM went BACK to Figure 8.1.10-1 on its own. The design choices were AECOM's throughout.

Cost updates

• LTR 384 amount: $4,615,622 (reduced from $5,466,392)
• Breakdown: Additional Construction $4,015,454, Buried Riprap $474,624, AECOM Design $125,544
• AECOM's own PCN 153 table: 397 hours, $109,169 (discrepancy of $16,375)
• No explanation for $850,770 reduction from LTR 372 amount

Schedule analysis gap

• GP 1-04.5(2)(d) requires "an analysis of the progress schedule showing the schedule change or disruption."
• Both Skanska and AECOM state: "a fully detailed schedule analysis is underway and will be delivered once complete."
• This requirement is not satisfied. WSDOT's determination should note the gap.

---

A. RCSR Comment Language Pattern (225 Comments)

Full analysis in research/Package_8_RCSR_Full_Analysis.md and research/Package_9_RCSR_Full_Analysis.md.

Package 8 (FHD, 202 comments): Zero direction. Key findings: (1) only 2 comments reference Table 2.30-B at all, both about stream morphology type (P005 issue, not lateral migration), (2) language is overwhelmingly consultative (54 "Please," 52 questions, 28 "Consider/Suggest/Recommend"), (3) Comment 134 (SMB) connects lateral migration to retaining wall total scour (supports BDM 8.1.10 distinction).

Package 9 (Structures, 23 comments): Zero direction. Key findings: (1) no Table 2.30-B references at all, (2) four comments cite BDM sections (Comments 3, 4 = BDM 8.1.10; Comment 8 = BDM 8.1.11.C; Comment 13 = BDM 8.1.5D) showing systematic BDM application, (3) Comment 2 (Preference) suggests design alternative that would have avoided the scour concern.

B. Correspondence Thread Summary

Full analysis in research/Correspondence_Analysis.md. Seven letters analyzed:

SL 9727-155 (Sep 12, 2025): WSDOT directed Contract-compliant Juanita Creek design conforming to stream simulation. This is the P005 triggering event. Addresses stream simulation, not lateral migration.

LTR 241 (Sep 29, 2025): Skanska responded that "strict adherence to the directive...is not feasible." Collaborative tone. Attached AECOM notice of protest cites contradictory requirements and ROW impossibility. P005 scope.

LTR 249 + AECOM Supplement (Oct 10, 2025): Most information-dense document. AECOM provides formal Section 1-04.5 supplement with meeting concurrence claims, WDFW positions, ROW constraints. Requests withdrawal of SL-155, additional ROW, or OIC. All P005 scope, but the OIC request pattern is relevant to DRB preparation.

SL 9727-179 (Oct 13, 2025): WSDOT acknowledged LTR 241/249 as Protest 005. Noted meeting minutes not provided within 5-day contractual requirement (Section 2.1.2.2.1).

SL 9727-205 (Nov 25, 2025): WSDOT denied P005. Directed Section 1-04.5(1) dispute procedure. Consistent with P019 denial posture.

SL 9727-233 (Jan 5, 2026): ROW acquisition is Design-Builder's responsibility per Section 2.24. Rebuts AECOM's ROW impossibility argument.

LTR 337 (Jan 30, 2026): Filed 66 days after P005 denial. Different claim (lateral migration RCSR vs. stream simulation) on the same structure. Now evolved into Protest 019 via LTR 372.

C. P005 Intersection

Full analysis in research/P005_LTR337_Scope_Map.md.

Why P005 matters: Same physical structure (Juanita Creek FP5), same correspondence chain, same designer (AECOM), same RCSR process. Skanska's DRB strategy will likely try to conflate them into "WSDOT kept changing requirements for Juanita Creek."

Scope boundary: LTR337/P019 scope = RCSR Comment 196, BDM 8.1.10 vs. Table 2.30-B, Package 9 Comments 3/4, $5.4M OIC, timeliness. P005 scope = stream simulation methodology, slope ratios, WDFW position, ROW feasibility.

BDM 8.1.10 is confirmed as P019-only. Not mentioned in any P005 correspondence.

DRB conflation risk: If Skanska tries to merge P005 and P019 at DRB, respond with: different contract provisions, different triggering events, different procedural postures. The "reversal" pattern breaks down: in P019 there was no reversal.

D. AECOM Presentation (Slides 16-17)

AECOM Sediment Depth Discussion Presentation, January 16, 2026. Attached to LTR 337.

What helps WSDOT:

1. Slide 4: AECOM acknowledged Table 2.30-B "low" designation and excluded lateral migration from sediment sizing. Consistent with our position.

2. Slides 16-17 (Skanska email Q&A): Skanska asked "Why was lateral migration included here? We fought so hard to not include lateral migration at the Sammamish River but seemed to accept it here." Shows Skanska was surprised. Inconsistent with claiming WSDOT "directed" inclusion.

3. AECOM response: "The final design of the wingwalls and headwall was completed before we received guidance to ignore lateral migration." Design preceded any guidance. AECOM's original professional judgment.

4. Slide 6 (Figure 7-6): AECOM's own FHD diagram shows "Stream Migration" labeled. AECOM's own engineering work incorporating lateral migration effects.

5. Tunnel depth not affected. AECOM confirms lateral migration "did not impact depth of sediment in tunnel." Narrows scope.

6. "Guidance to ignore lateral migration" (DRB talking point). AECOM says their FHD was from "before we received guidance to ignore lateral migration" (Slide 16). The next bullet notes "Sonia closed RCSR comments on lateral migration on July 28, 2025." These are two separate facts, not one event. Sonia (a WSDOT team member who administered comment closure) confirmed the contract designation ("low" per Table 2.30-B, file a DBIC if you disagree). She would not have said "ignore lateral migration." The "guidance to ignore lateral migration" most likely came from Skanska to AECOM. Skanska's own question on the same slide confirms their posture: "We fought so hard to not include lateral migration at the Sammamish River but seemed to accept it here." Skanska was pushing against lateral migration inclusion and likely directed AECOM to follow the contract "low" designation. AECOM's design incorporating lateral migration was their independent professional judgment, completed before Skanska told them to stop. Reserve for DRB. Do not deploy at determination stage. At DRB, if Skanska identifies the "guidance" source, respond accordingly. If they don't clarify, do not volunteer an interpretation. The core point stands under any reading: AECOM designed for lateral migration based on their own analysis before receiving any guidance on the topic. Update April 14, 2026: Gabe Ng's April 14, 2026 email and the complete June 13 - July 25, 2025 thread Gabe provided contain no statement that could be characterized as "guidance to ignore lateral migration." Gabe never directed AECOM to ignore lateral migration. The Design-Builder's burden at DRB to identify the source of the claimed "guidance" is unchanged.

What helps Skanska:

1. Design impact was real. Wingwall, headwall, and buried riprap all affected. The $5.4M figure may be supported by actual design differences.
2. BDM figures comparison (Slide 14) visually shows the design difference.
3. "Significant effort would have been required to redesign." Supports "costs committed" argument.
4. Comment resolution as condition of RFC.

E. FHD and Appendix O Findings

Source: AECOM Draft Final Hydraulic Design Report, Juanita Creek at I-405 MP 21.94 (BY-CRE-01827, Package 8, submitted January 28, 2025). Reviewed by WSDOT GNg and HQH, dated February 18, 2025.

Section 7.1 (Lateral Migration):

• HEC-20 rapid assessment score = 69 = "good" stream stability
• Vertical instability rating (0.43) slightly dominant over lateral (0.47)
• Risk "low to moderate" (consistent with Table 2.30-B "low" designation)
• Key finding (FHD p.73): "Although the risk for lateral migration is considered low to moderate, the risk in relation to the structure is assumed to occur for the purposes of scour analysis and estimation of total scour. The geotechnical data available at this time are not sufficient to exclude the risk of lateral migration from the scour analysis until detailed geotechnical data (i.e., competent bedrock, geotechnical evaluation for soil erodibility, stream power versus soil erodibility, etc.) is available to support the assessment of no lateral migration being anticipated over the life (75+ years) of the proposed structure."
• This was AECOM's independent professional judgment. The FHD acknowledges the risk is "low to moderate" but chose to include lateral migration because the geotech data was insufficient to exclude it. This decision preceded WSDOT Comment 196.

Section 7.5 (Total Scour) and Table 7-4 (Scour Analysis Summary):

Component	Scour Design Flood	Scour Check Flood
Long-term degradation (ft)	0.12	0.12
HEC-18 contraction scour (ft)	0	0
NCHRP 24-20 contraction and abutment scour (ft)	0.53	1.04
Total depth of scour (ft)	0.65	1.16
WSDOT minimum scour depth (ft)	3	3

The calculated total scour (0.65-1.16 ft) is far below the 3 ft WSDOT minimum. The minimum governs per WSDOT Hydraulics Manual. The 1.04 ft scour check flood depth "is applied below the channel thalweg and horizontally to the structure walls due to the risk of lateral migration over the lifespan of the proposed structure" (FHD p.81).

Significance for P019: The scour depth delta between "with" and "without" lateral migration is small. The cost driver is NOT deeper scour. The cost driver is the horizontal application of scour to the wingwalls (BDM 8.1.10 Figure 8.1.10-2 treatment), which requires the soldier pile walls to resist lateral erosion of the soil supporting them. This drives embedment depths (14-19 ft per structural calcs) and tieback anchors.

Structural plan progression confirms this (verified 2026-06-20 against the full submittal record). A version-by-version comparison of the East and West portal wingwall plans across the preliminary, final, and Released for Construction submittals shows that scour does not govern the wingwall foundation depth. On the East Portal the bottom-of-scour elevation is essentially identical in the preliminary and final plans (EL 214.25 and EL 214.23), and the preliminary wingwall toe already sat 17 to 24 feet below it, 8 to 12 times the 2-foot cover BDM 8.1.10 requires. The scour requirement was static and was satisfied many times over before any pile was deepened. The three piles nearest the headwall (WW3-01, WW3-02, WW3-03) did deepen from 19 to 24 feet of embedment at the final submittal, and two WW4 end piles deepened from 14 to 15 feet with one WW4 pile deleted, but that change cannot be a scour response because the scour line did not move and the wall already exceeded the scour requirement by an order of magnitude. The deepening coincided with an increase in the wingwall design height (WW3-01 grew from 36'-3" to 37'-5"), which points to retained height and global stability as the driver, not scour. On the West Portal the embedment held at 25 to 26.5 feet across all three versions, pile-for-pile identical in the final and Released for Construction sets, even though the bottom-of-scour elevation was raised approximately 7 feet between the final and RFC plans. Scour moved 7 feet and the foundation did not. The explicit bottom-of-scour label and the 2-foot dimension were first annotated at the final submittal, but the scour elevation itself was already in the preliminary plans, and the deep soldier-pile foundation set well below it was already drawn there, citing the Design-Builder's own June 2024 hydraulic report on its face. The foundation did not deepen in response to any review comment, and the East Portal final RCSR records no change to pile embedment. Lateral migration drove the horizontal scour application, not the foundation depth, and is therefore not the cost driver Skanska's claim assumes. Source: full structural submittal record (East BY-CRE-02210 / 03543 / 04325, West BY-CRE-02327 / 03550 / 04750), retrieved from the R2 mirror and verified 2026-06-20. Per-pile elevations and the scour-vs-embedment margins are in references/Submittals/_MANIFEST_and_completeness_matrix.md and analysis/research/P019_Scour_vs_Embedment_DATA.md.

Section 8 (Scour Countermeasures): "No countermeasures are recommended to protect the abutments from scour at the Juanita Creek crossing of I-405." The FHD did not recommend scour countermeasures at the structure itself. (Buried riprap is a separate downstream countermeasure, addressed under SKA-0297.)

Table 9-1 (Report Summary): Confirms "Lateral migration: No" under floodplain continuity and "Scour countermeasures: No."

Appendix O (Lateral Migration Rapid Assessment):

• Indicator 8 (Bank soil): "Gray silty sand" -- rated Fair (8) = erodible soils
• Field notes: "Bank erosion was encountered in various locations along Juanita...lateral scour further downstream into a resident yard"
• Indicator 1 (Watershed): "36% impervious" -- rated Fair (9) = urbanized watershed

These findings (from the Design-Builder's own technical work) support "NOT low" conditions at the site. The reviewer summarized what AECOM's analysis showed. AECOM reached its engineering conclusion independently, then WSDOT Comment 196 pointed out that AECOM's own findings contradicted a pure "low" treatment.

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A. Mischaracterizes the RCSR Comments

LTR 337 and LTR 372 claim WSDOT "directed" NOT low treatment. The actual Comment 196 text shows DJS was summarizing AECOM's findings and gave discretion to disagree. The Design-Builder's characterization is inaccurate.

B. Does Not Acknowledge Their Own Findings

The FHD and Appendix O found erodible soils, beaver activity, and unknown historical channel changes. These findings support "NOT low" conditions. The Design-Builder cannot claim designing for conditions their own analysis identified is extra work.

C. No Distinction Between Requirements

LTR 337 and LTR 372 conflate fish passage lateral migration (Table 2.30-B) with wingwall scour (BDM 8.1.10). Comment 41 explicitly connects to "retaining wall designs." These are separate requirements.

D. No Timely Protest of RCSR Comments

FHD comments issued approximately February 2025. Design-Builder proceeded through RFC (December 2025) without formal objection. Approximately 10-11 months. GP 1-04.5 required timely protest.

E. No DBIC Request

If the Design-Builder sought to change the design approach, GP 1-04.4(2) was the appropriate mechanism. No DBIC submitted. The July 28, 2025 comment closure explicitly told the DB to file a DBIC if it disagreed.

F. No Schedule Analysis

LTR 337 did not include schedule impact analysis. LTR 384 (supplemental) still does not provide one. Both Skanska and AECOM state a "fully detailed schedule analysis is underway." GP 1-04.5(2)(d) requires "an analysis of the progress schedule showing the schedule change or disruption." The supplemental claims "up to 6 months" delay and "likely to affect the Critical Path" but provides no CPM analysis or supporting documentation. This requirement remains unsatisfied.

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A. Change Claim

WSDOT did not authorize or require a change under GP 1-04.4(1). The RCSR comments were design review, not direction. Section 1-02.1 shields all WSDOT comments on Design Documents from amending contract requirements. Section 1-03.5 bars IED-based entitlement.

Finding: Does not constitute a change. No OIC is warranted.

B. Cost (Updated: $4,615,622 per LTR 384)

Cost history: LTR 337 claimed $5,466,392. LTR 384 reduced this to $4,615,622, a decrease of $850,770 with no explanation for the reduction.

LTR 384 breakdown:

Item	LTR 384 Amount	WSDOT Assessment	Attributable to WSDOT Direction?
Additional Construction (Wingwalls, Headwalls, Tunnel)	$4,015,454	No line-item backup provided. Actual scour is 0.65-1.16 ft (3 ft minimum governs). Embedment depth (14-19 ft) driven by retained height (31-42 ft) and soil conditions. Lateral migration drives horizontal application (BDM Figure 8.1.10-2), not vertical depth. AECOM's own FHD found conditions supporting inclusion. AECOM's June 13, 2025 email: "both tunnel and wingwalls are designed for full scour depth" before any methodology was accepted.	NO
Buried Riprap Countermeasures	$474,624	Section 2.30.5.6 requires DB to design scour countermeasures. FHD Section 8: "No countermeasures are recommended to protect the abutments from scour." Buried riprap protects the existing MSE wall downstream. AECOM's June 13 email confirms riprap was triggered by Jason Pang's structural comment on the MSE wall (TR 2.13.4 obligation). TFM #38: "Design builder proposing buried rip-rap for scour protection" -- DB proposed it.	RESERVED (SKA-0297)
Design Costs (AECOM)	$125,544	AECOM's own PCN 153 table shows 397 hours / $109,169. Discrepancy of $16,375. Skanska's figure is unsupported by AECOM's own documentation.	NO
Total	$4,615,622

Prior LTR 337 breakdown (for reference):

Item	LTR 337 Amount
Additional structural elements	$4,015,454
Additional shoring elements	$815,892
Buried riprap countermeasures	$474,624
Design costs	$160,423
Total	$5,466,392

Delta analysis: The $850,770 reduction appears to come primarily from removing "additional shoring elements" ($815,892) and reducing design costs ($160,423 to $125,544). The construction and buried riprap amounts are unchanged. The removal of shoring elements with no explanation weakens the certainty of the original claim.

The attribution problem: Skanska assumes all lateral migration-related design is attributable to WSDOT direction. The evidence shows AECOM's original design included lateral migration before any WSDOT comment. AECOM's analysis found supporting conditions. BDM 8.1.10 independently required total scour evaluation. Section 2.30.5.6 required scour analysis.

Scour depth reality check: Skanska's framing suggests lateral migration dramatically increased scour. The FHD shows total scour is 0.65-1.16 ft, governed by the 3 ft WSDOT minimum regardless. The cost driver is horizontal application to wingwalls (BDM 8.1.10 Figure 8.1.10-2), not deeper scour. Further, the wingwall retained heights (31-42 ft) are driven primarily by the tunnel excavation depth, not scour. The incremental cost of lateral migration treatment on walls that already need to be 31-42 ft tall for other reasons is far less than $5.4M. Engineering review should quantify this.

Cost attribution (qualitative, reserved for DRB): Even setting aside the entitlement question, much of the $5.4M cost was driven by the Design-Builder's own wingwall configuration choice. Package 9 Comment 2 (HQH, "Preference") suggested angled wingwalls at 25-45 degrees off the headwall. WSDOT's suggestion would have reduced wall length, wall depth, embedment depth, soldier pile count, tieback anchor rows, scour exposure, and buried riprap need. It would also have stayed on existing ROW (avoiding the SKA-0297 property rights problem entirely). The Design-Builder chose parallel wingwalls instead. The parallel configuration drove the cost magnitude. This is a design choice defense. It does not argue whether lateral migration analysis was required. It argues that the cost magnitude was driven by the DB's configuration, not by WSDOT comments. See P019_Engineering_Questions.md Cost Attribution section for qualitative categories. Quantitative analysis requires independent estimate (future phase).

Finding: Not entitled to cost adjustment. Costs result from AECOM's professional analysis and mandatory standard compliance, not WSDOT direction.

C. Schedule

No schedule analysis provided per GP 1-04.5(2)(d). WSDOT reserves the right to contest any schedule claim raised in the supplemental.

Finding: Not entitled to time extension based on current submittal.

D. Buried Riprap (Reserved for SKA-0297)

The buried riprap countermeasures are unique: they protect the "existing MSE wall downstream of the structure" (not the new fish passage structure). The countermeasure obligation derives from Section 2.30.5.6. Property rights for the riprap footprint are at issue under SKA-0297 (SL 9727-233).

P019 determination should acknowledge the buried riprap claim but defer to SKA-0297 for resolution.

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A. Defense Layering

Three defense lines, deployed in sequence:

Layer	Defense	Deployed In	Notes
1	RCSR comments were design review with discretion (Comment 196)	SL 9727-280 (determination)	Primary defense
2	Section 2.30.5.6 required the scour analysis (contractual obligation)	SL 9727-280 (determination)	Secondary defense
3	BDM 8.1.10 requires total scour for retaining walls (existing Mandatory Standard)	Reserved for DRB	Requires engineering support

Why BDM 8.1.10 is reserved for DRB:

1. Section 2.30.5.6 carries the contractual obligation defense sufficiently for a determination letter.
2. BDM opens technical arguments (Does 8.1.10 apply to fish passage wingwalls? Does "low" mean Figure 8.1.10-1? Is there a conflict?) that require engineering testimony.
3. Deploying BDM at DRB as a third defense line, with engineering support, is stronger than deploying it in a letter without technical backing.

Considered but not relied upon: Section 2.30.5.2.1 Scour Provision. This provision resolves conflicts between SFZ dimensions and scour analysis results. WSDOT does not rely on it because: (1) our argument is that there is no conflict between Table 2.30-B and scour requirements, (2) citing a conflict-resolution provision implies a conflict exists, and (3) we have not confirmed whether wingwall foundations actually encroach below the CBE or beyond the SFZ Width. If raised at DRB, respond: "The scour provision addresses conflicts between SFZ dimensions and scour requirements. It is not relevant here because WSDOT's position is that there is no conflict."

B. Strengths and Weaknesses

WSDOT strengths:

1. Comment 196 text is unambiguous: "seems like," "please revise" = discretion
2. Section 1-02.1 shield is textually absolute for comments
3. Section 1-03.5 entitlement bar and burden-shifting favor WSDOT
4. AECOM's own analysis found conditions supporting the design
5. AECOM's design preceded any guidance on lateral migration
6. 225 comments analyzed, zero directive language
7. July 28, 2025 comment closure confirmed "low" and directed DBIC if disagreed
8. DB proceeded 10-11 months without protest

Skanska strengths:

1. Design impact was real. $5.4M may be supported by actual design differences.
2. BDM figures comparison makes the scope argument tangible.
3. "Significant effort to redesign" supports costs committed.
4. RCSR resolution was a practical prerequisite for RFC.

C. Admissions Against Interest

Statements by Skanska/AECOM that undermine their position:

1. Skanska email: "Why was lateral migration included here? We fought so hard to not include lateral migration at the Sammamish River but seemed to accept it here." -- Shows Skanska considered the decision to be AECOM's.
2. AECOM Slide 4: Acknowledged Table 2.30-B "low" and excluded lateral migration from sediment sizing. They knew the contract said "low."
3. AECOM Slide 16: "Design completed before we received guidance to ignore lateral migration." -- Design preceded guidance.
4. AECOM Slide 17: Tunnel depth "not affected" by lateral migration. -- Narrows scope.
5. LTR 337 filing 66 days after P005 denial. Alternative cost recovery inference.
6. Skanska's framing question (Slide 17): "Would like AECOM to review the attached and included information and depict in AECOM's opinion how WSDOT influenced the design here on the lateral migration front." Shows Skanska directing AECOM to build the "WSDOT influenced" narrative. AECOM's response is more measured: design "may have been different if received guidance on lateral migration sooner." AECOM did not say WSDOT directed the design.
7. Slide 16 identifies the "guidance" source: Two separate facts on Slide 16: (1) AECOM received "guidance to ignore lateral migration" and (2) Sonia closed RCSR comments July 28, 2025. These are not the same event. The "guidance" most likely came from Skanska to AECOM, directing compliance with the contract "low" designation. Sonia's closure was administrative confirmation. See Section IV.D item 6.

D. P003 Coordination

P003 status: DRB (Notice of Dispute filed LTR 348, February 12, 2026). Same DRB panel may hear both.

Alignment rules:

• Do not argue Table 2.30-B is "merely informational." WSDOT relied on it in P003.
• Do not argue engineering analysis can override contract designations. That is Skanska's P003 argument.
• Consistent position: Table 2.30-B designations stand as written. WSDOT enforces them. RCSR review is separate from contract enforcement.

RCSR characterization caution: The P003 memo characterizes an RCSR comment as the "First written WSDOT position." P019 calls RCSR comments "design review, not direction." These are reconcilable:

• At Sammamish (P003): the RCSR reinforced an explicit contract mandate (Section 2.30.5.2.1 "shall apply").
• At Juanita (P019): the RCSR identified an internal inconsistency in the designer's work.

Do NOT make blanket statements that RCSR comments can never constitute a WSDOT position. Characterize each comment on its own terms. The unifying principle: contract requirements are the floor.

E. Engineering Review Items

Items from AECOM presentation requiring engineering verification:

#	Item	Source	Question	Priority
1	AECOM scour values	FHD Table 7-4	RESOLVED. Total scour = 0.65 ft (design flood) to 1.16 ft (check flood). WSDOT 3 ft minimum governs. LTD = 0.12 ft. Contraction scour = 0. Abutment scour = 0.53 ft (design) to 1.04 ft (check). The scour depth delta from lateral migration is effectively zero at the structure because the 3 ft minimum governs regardless. The cost driver is horizontal application to wingwalls (BDM 8.1.10), not deeper scour. See Section IV.E.	RESOLVED
2	"Guidance to ignore lateral migration"	Slide 16	RESOLVED (RESERVED FOR DRB). Source identified. Slide 16 has two separate facts: (1) AECOM designed "before we received guidance to ignore lateral migration" and (2) "Sonia closed RCSR comments on lateral migration on July 28, 2025." These are not the same event. Sonia administered comment closure confirming the contract "low" designation. She would not have said "ignore lateral migration." The "guidance" most likely came from Skanska to AECOM, directing AECOM to follow the contract "low" designation. Skanska's own question confirms: "We fought so hard to not include lateral migration." AECOM designed for LM based on own professional judgment, then Skanska told them to stop. Do not deploy at determination stage. At DRB, respond to the source if Skanska identifies it. Do not volunteer an interpretation. See Section IV.D item 6 for full analysis.	RESOLVED (RESERVED FOR DRB)
3	RCSR comment closure (July 28, 2025)	Slide 16	What does "closed" mean? Reviewer accepted response, or AECOM resolved?	MEDIUM
4	Wingwall depth "up to 15 feet"	LTR 337 Section 3(c)	RESOLVED. Structural calcs (AECOM, Feb 24, 2025) confirm: WW3 retained heights 18'-36' (12 piles, embedment 17-19 ft). WW4 retained heights 10'-34' (10 piles, embedment 14-19 ft). Soldier piles W21x101 and W24x104 with 1-3 rows of permanent tieback anchors. "Up to 15 feet" likely refers to embedment depth increment, not total wall height. Total retained heights (31-42 ft max) are driven by tunnel excavation depth, not scour. The 14-19 ft embedment is driven by soil conditions and retained height, with lateral migration treatment affecting the horizontal scour assumption but not directly adding 15 ft. FPS-02 Note 4: "designed for scour in accordance with the hydraulic report dated June 2024."	RESOLVED
5	MSE wall classification	Slides 18-19	RESOLVED. Wall 2185L-A is an existing MSE wall. RFP Section 2.6 (Seismic Design Requirements for Existing Retaining Walls): "The existing MSE Wall, Wall 2185L-A at the Juanita Creek Culvert will require full or partial replacement to install the fish passage structure. Within a minimum lateral distance of 100 feet from the outer edges of this culvert structure, any remaining parts of existing wall 2185L-A shall meet all design requirements of this Contract, including seismic design." Also listed in Section 2.6 pre/post-construction survey requirements. The contract anticipated the MSE wall would be affected by the fish passage work. Section 2.13.4 requires existing wall elements "affected by the Work" to "meet the minimum foundation cover requirements or be protected against scour to that level." This supports WSDOT's position that scour protection for the existing MSE wall is a contract obligation, not additional scope. Relevant to SKA-0297 buried riprap analysis.	RESOLVED
6	Design alternatives and cost allocation	Slide 17, Comment 2 (Pkg 9)	PARTIALLY RESOLVED (qualitative). Package 9 Comment 2 (HQH, "Preference") suggested angled wingwalls (25-45 degrees) instead of parallel. DB chose parallel. Qualitative savings categories from angled wingwalls: (1) shorter wall length, (2) reduced retained height, (3) less embedment depth, (4) fewer tieback anchor rows, (5) fewer soldier piles, (6) no ROW encroachment (avoids SKA-0297), (7) less scour exposure per BDM 8.1.10, (8) less buried riprap. The parallel wingwall orientation (DB's choice) drove the depth/cost problem ($5.4M claim), the property rights problem (SKA-0297), and the scour exposure problem. This is a design choice cost attribution defense. Reserve for DRB. Quantitative analysis requires independent estimate (future phase). See P019_Engineering_Questions.md Cost Attribution section.	HIGH
7	Wingwall depth vs. riprap trade-off	Slide 17	Reducing wingwall depth increases buried riprap. Optimal balance?	LOW

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ID	Request	Disposition	Rationale
LTR372-R1	Reconsider and withdraw SL 9727-280	DENIED	SL 9727-280 correctly interprets contract requirements. RCSR comments were design review. IED is properly issued under GP 1-03.5.
LTR372-R2	Process OIC for $5,466,392	DENIED	No OIC warranted. RCSR review is not direction. GP 1-03.5 bars IED-based entitlement. DB bears burden of proving interpretation incorrect or unreasonable.
LTR372-R3	Direction on buried riprap countermeasures	RESERVED	Addressed in WSDOT's response to SKA-0297 (Juanita Creek Property Rights).
LTR372-R4	14 calendar day extension for supplemental	DENIED	Extension denied. Standard GP 1-04.5 deadline applies. Supplemental due March 24, 2026 (14 calendar days from March 10, 2026).

Reservation of rights: Skanska reserves all rights including DRB referral under GP 1-04.5(1).1. Noted.

AECOM protest: AECOM notice of protest (Jon Guerrero, PE, March 9, 2026, PCN-00153). AECOM is a subcontractor to Skanska. AECOM's protest is processed through the Design-Builder per the contract. WSDOT does not have a direct contractual relationship with AECOM. Noted.

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Section	Purpose
GP 1-02.1	WSDOT comment shield. "No comments... shall be deemed, construed, or interpreted to amend, supersede, or alter."
GP 1-03.5	IED authority. Entitlement bar. Burden-shifting.
Table 2.30-B	Fish passage lateral migration classification ("low" at Juanita Creek)
Section 2.30.5.2.1	Table 2.30-B compliance and precedence clause
Section 2.30.5.6	Scour analysis requirements. DB "shall perform a scour analysis" including LM risk. "Shall locate, design and construct any required scour countermeasures."
BDM Section 8.1.10	Retaining wall scour requirements. Total Scour includes lateral migration effects. Reserved for DRB.
Section 2.13.4	BDM as Mandatory Standard for scour
GP 1-04.4(1)	OIC requires WSDOT directive
GP 1-04.4(2)	DBIC mechanism (DB never submitted one)
GP 1-04.5	Protest procedure. 14-day window. Supplemental and determination timeline.
GP 1-04.1	Contract Price includes compliance costs

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This section captures the post-determination analysis supporting the dispute acknowledgment letter. Skanska LTR 417 was filed April 28, 2026 (Day 14 of the dispute window after WSDOT SL 9727-326 transmitted April 14, 2026). AECOM's separate Notice of Dispute dated April 24, 2026 is attached as a sub-tier internal communication adopted via GP 1-05.15. See Response Matrix LTR417 layer for assertion-level dispositions and chronology.md for transmittal record.

X.A. Two-Gate DRB Qualification Verdict

Gate 1 (Subject-Matter Eligibility) under GP 1-04.5(1).1.2: OPEN. The dispute concerns interpretation of the Contract (Table 2.30-B classification, Section 1-02.1 comment shield, Section 1-03.5 IED authority, BDM 8.1.10 Mandatory Standard) and entitlement to additional compensation and time. Both eligibility categories satisfied.

Gate 2 (Procedural Conditions Precedent) under GP 1-04.5 + GP 1-04.5(1): OPEN. Every contractual timing window was met (most on the last day):

Step	Required	Skanska Action	Compliant
Notice of Protest within 14 calendar days of WSDOT Written Determination	Mar 10, 2026	Skanska LTR 372 filed Mar 10, 2026	Yes (Day 14)
Supplemental within 14 calendar days of protest	Mar 24, 2026	Skanska LTR 384 filed Mar 24, 2026	Yes (Day 14)
WSDOT no-merit determination within 21 calendar days of supplemental	Apr 14, 2026	WSDOT SL 9727-326 transmitted Apr 14, 2026	Yes (Day 21)
Notice of Dispute within 14 calendar days of receipt of no-merit determination	Apr 28, 2026	Skanska LTR 417 filed Apr 28, 2026	Yes (Day 14)
Election to use DRB	Required	Skanska LTR 417 expressly requests DRB	Yes

Verdict: WSDOT cannot procedurally bar referral to the Disputes Review Board. Asserting otherwise would itself be a procedural defect on the WSDOT side.

X.B. Procedural Limiters That Survive Into the Hearing

WSDOT's acknowledgment letter will document two procedural limiters. Both are scope, quantum, and entitlement constraints operating at the hearing rather than referral bars.

Limiter B (Schedule analysis record gap): GP 1-04.5(2)(d) required the supplemental Written Statement to include an analysis of the progress schedule showing the schedule change or disruption. Skanska LTR 384 did not include this analysis. Skanska LTR 417 does not include this analysis. Skanska represents that the analysis is underway and will be provided as a future supplement. GP 1-04.5 does not establish a procedure for supplementing a Notice of Dispute. WSDOT noted the gap in WSDOT SL 9727-326 paragraph 8 and proceeded to merits. The framing for the acknowledgment letter is "the schedule entitlement is unsupported on the existing record," not "barred." See feedback memory feedback-no-reserves-all-rights.md for the principle that the contract speaks for itself.

Limiter C (Cost elements not in supplemental): GP 1-04.5(2)(b) required the supplemental Written Statement to include a full discussion of the circumstances which caused the protest. Skanska LTR 417 introduces the line items "Stream Re-Alignment" ($79,340) and "Design for Stream Re-Alignment" ($50,183), and an increase in the AECOM design cost from $125,544 to $401,941. None of these elements were in Skanska LTR 384. WSDOT's framing for the acknowledgment letter is "WSDOT understands the dispute to be limited to the circumstances and bases set forth in Skanska LTR 384, the supplemental Written Statement."

Three-stage operationalization. The acknowledgment letter is record preservation. The application of each limiter at the position paper and hearing stages is operationally distinct.

Stage	Limiter B (Schedule analysis record gap)	Limiter C (Cost elements not in supplemental)
Acknowledgment letter	Cite the GP 1-04.5(2)(d) gap. Plain contract language. No "barred" overreach. No reservation of rights.	Cite GP 1-04.5(2)(b). Name the Stream Re-Alignment line items and the AECOM design cost growth. State that WSDOT understands the dispute to be limited to the circumstances and bases in Skanska LTR 384.
Position paper	Argue schedule entitlement is unsupported on the existing record. Decline to engage on the merits with any post-supplemental CPM analysis filed by the Design-Builder. If the Design-Builder files such an analysis as a position-paper attachment, treat as outside the protest record.	Argue the dispute is limited to circumstances and bases set forth in Skanska LTR 384. Object to introduction of the Stream Re-Alignment cost element and the AECOM design cost growth as new bases for entitlement.
Hearing	If the Disputes Review Board allows the schedule analysis in evidence, limit the cost-and-time-impact rebuttal to the value supportable on the original record.	If the Disputes Review Board allows the new cost elements in evidence, focus the rebuttal on the substantive merits. The substantive defenses are in WSDOT SL 9727-326 paragraph 3. The Design-Builder's wingwall scour analysis obligation arises from BDM 8.1.10 as a Mandatory Standard incorporated through TR 2.13.4. The Design-Builder's scour countermeasure design obligation, which is the contractual basis for any Stream Re-Alignment cost element, arises from TR 2.30.5.6 and HEC-23 (Federal Highway Administration Hydraulic Engineering Circular No. 23, listed in TR 2.30 Mandatory Standards and incorporated by reference through BDM 8.1.10). The reviewer cited the controlling standards. The reviewer did not create a new directive.

X.C. Verified Facts From Comprehensive Document Review (April 29, 2026)

Initial scan of LTR 417 against summary sources flagged four "new at dispute stage" assertions. Comprehensive review against the four corners of LTR 384 plus AECOM PCN-153 produced corrections:

Item Initially Flagged as New	Verification Against LTR 384 + PCN-153	Status
WSDOT had already rejected Figure 8.1.10-1	LTR 384 Section 6 expressly raises this. PCN-153 item 2 describes the Jan-Feb 2025 discussions on Figure 8.1.10-1 versus Figure 8.1.10-2.	Not new
WSDOT directed lateral migration calculations at the Feb 11, 2025 Task Force meeting	LTR 384 / PCN-153 item 2 references Jan-Feb 2025 discussions generally. The specific Feb 11 date is more precise than the supplemental but within the same period.	Date-specific, immaterial
WSDOT rejected AECOM's 60-foot valley width analysis	PCN-153 item 4 expressly states the 60-foot valley width was proposed and rejected.	Not new
WSDOT's RCSR comments directed use of Figure 8.1.10-2	LTR 372 Section 2.1 and LTR 384 Section 2 both raise this.	Not new
OIC theory under GP 1-04.4(1) (vs. constructive direction)	LTR 384 Requested Relief (b) was already an OIC request under GP 1-04.4(1). Constructive direction was the analytical theory; OIC was the relief mechanism.	Not a theory pivot

Genuinely new at dispute stage:

1. Stream Re-Alignment cost element ($129,523 combined) — scope emerging from AECOM's April 7, 2026 stream-realignment proposal, after the supplemental window closed.
2. AECOM design cost growth from $125,544 to $401,941 — no PCN-153 backup for the increase. PCN-153 documented 397 hours and $109,169.

X.D. Substantive Defense Already in the Determination

The internal-contradiction theory I considered (PCN-153 item 9 admitting the final RFC scour countermeasure used Figure 8.1.10-1 without lateral migration at 38 ft, contradicting LTR 384 Section 8's tunnel claim) does not need to be argued as a procedural limiter. The substantive defense is already in WSDOT SL 9727-326 paragraph 3:

"The 'shall' language in Package 9 structural review Comments 3 and 4 quotes Bridge Design Manual (BDM) Section 8.1.10 verbatim. BDM requirements are existing mandatory standards, not new WSDOT directives. Compliance with mandatory standards is the Design-Builder's responsibility under the Contract Price per GP 1-04.1."

Whether AECOM ultimately built (or builds) the structure under Figure 8.1.10-1 or Figure 8.1.10-2 is the Design-Builder's professional engineering judgment under BDM 8.1.10. The reviewer cited the BDM. The reviewer did not create a new directive. This defense does not need restatement in the acknowledgment letter. It is reserved for the position paper.

X.E. AECOM Pathways at the Disputes Review Board

AECOM's participation at the DRB hearing operates through GP 1-04.5(1).1.8. There is no separate "outside party" mechanism in the Contract, the Three-Party Agreement (Form 134-091, standard), or the F04 DRB Forms and Guidelines (Appendix F4 of the RFP). AECOM has two pathways:

1. Subcontractor authorized representative. Required and automatic. GP 1-04.5(1).1.8 (Attendance, item 2.e) provides that "At Board hearings regarding disputes involving a Subcontractor, the Design-Builder shall require and ensure that each Subcontractor involved in the dispute have present an authorized representative with actual knowledge of the facts underlying the Subcontractor disputes."

2. Outside Expert. With proper disclosure. GP 1-04.5(1).1.8 (Use of Outside Experts, item 1.a) requires the Design-Builder to notify WSDOT and the Board in writing no less than 30 calendar days prior to the pre-hearing submittal due date. The notice must include: the expert's name and area of testimony; a Section 1-04.5(1).1.5 item 3(b) disclosure statement; and a statement of qualifying experience and training.

The acknowledgment letter does not need to address AECOM standing. Both pathways self-execute at the hearing-prep stage.

X.F. Cost Trajectory of the Claimed Amount

For internal record only. Reduction of stated quantum across the protest, supplemental, and dispute stages:

Document	Date	Stated Amount
Skanska LTR 372 (Notice of Protest)	Mar 10, 2026	$5,466,392
Skanska LTR 384 (Supplemental)	Mar 24, 2026	$4,615,622
Skanska LTR 417 (Notice of Dispute)	Apr 28, 2026	$3,179,809

Cumulative reduction from initial claim is 42 percent. Per Zach's drafting principle, quantum is downstream of merit and the number will likely change again. The acknowledgment letter will not address the cost trajectory directly. WSDOT's record position is that the dispute is limited to the circumstances and bases set forth in Skanska LTR 384.

X.G. Action Items

#	Item	Priority	Success Condition
1	Draft dispute acknowledgment letter	HIGH	Markdown draft completed in analysis/. Built to docx via python-docx script following the existing P019 deliverables pattern. Reviewed by Zach. Transmitted to Evelyn for signature. SL number assigned. Filed at OneDrive 9.02 To Skanska.
2	Position paper preparation	HIGH	Outline drafted. Common Reference Documents (CRDs) assembled. Statement of Dispute and Question drafted. Draft circulated to project staff per Brickyard Protest Dispute and Claims Summary best practices.
3	Retrieve structural design submittals from Z: drive	MEDIUM	Robocopy commands executed on Remote Desktop. Files synced to OneDrive Brickyard tree under 09727_DataExports/Protest_019_Designs/. Copies linked into protest_019/references/Submittals/ as needed for citation in the position paper.
4	Compile Common Reference Documents (CRDs)	MEDIUM	Combined index of WSDOT and Design-Builder reference documents prepared in single binder convention. Index circulated to the Design-Builder for review prior to submission to the Disputes Review Board.
5	Evaluate joint Statement of Dispute and Question(s) with the Design-Builder	MEDIUM	Draft statement sent to the Design-Builder. Either agreement reached on a joint statement or both versions submitted per GP 1-04.5(1).1.8.

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[INTERNAL MEMO -- Protest 019 -- SKA-0303 -- Prepared March 11, 2026 -- Updated April 6, 2026 (LTR 384 supplemental incorporated) -- Updated April 29, 2026 (Section X added: LTR 417 Notice of Dispute procedural posture)]