3. Response to Comments with Mitigation Monitoring Plan (MMP No. 398)

ATTACHMENT NO. 3
O
C River Walk Project
Response to Draft Environmental Impact Report Comments
• R
esponse to Draft Environmental Impact Report Comments
https://www.anaheim.net/DocumentCenter/View/67086/OCRW_Response-to- Comments?bidId=

FINAL EIR
Response to Comments
Environmental Impact Report No. 357
OC River Walk Project
Lead Agency:

City of Anaheim
Community Services Department, Parks Division
200 South Anaheim Boulevard, Suite 433
Anaheim, California 92805
Contact: Ana Straabe, Principal Project Planner
(714)
765
-4463
[email protected]
Prepared by:
101
Progress, Suite 250
Irvine, California 92618
N
ovember 2025

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Table of Contents
Section 1 Introduction ......................................................................................................... 1-1

1.1 Introduction ................................................................................................... 1-1

1.2 Format of the FEIR ....................................................................................... 1-1

1.3 CEQA Requirements Regarding Comments and Responses ...................... 1-2 Section 2 Response to Comments ..................................................................................... 2-1 Section 3 Revisions to the Draft EIR .................................................................................. 3-1

3.1 Introduction ................................................................................................... 3-1

3.2 DEIR Revisions in Response to Written Comments ..................................... 3-1

Tables
Summary of Public Comments .................................................................................................. 2-1 Appendix
Appendix A Updated Hydrology Report (Appendix G to DEIR) Appendix B Attachments to Letter 7 from Shiishongna Tongva Nation Appendix C Mitigation Monitoring Program No. 398
Appendix D Updated Figures

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Section 1 Introduction

1.1 Introduction
This Final Environmental Impact Report (FEIR) has been prepared in accordance with the California Environmental Quality Act (CEQA) as amended (Public Resources Code §§ 21000 et seq.) and CEQA Guidelines (California Code of Regulations §§ 15000 et seq.).

According to the CEQA Guidelines, Section 15132, the FEIR shall consist of:
(a) The Draft Environmental Impact Report (DEIR) or a revision of the Draft; (b) Comments and recommendations received on the DEIR either verbatim or in summary; (c) A list of persons, organizations, and public agencies comments on the DEIR; (d) The responses of the Lead Agency to significant environmental points raised in the review and consultation process; and
(e) Any other information added by the Lead Agency.

This document contains responses to comments received on the DEIR for the OC River Walk Project (project) during the public review period, which began July 24, 2025, and closed September 8, 2025. This document has been prepared in accordance with CEQA and the CEQA Guidelines and represents the independent judgment of the Lead Agency. This document and the circulated DEIR comprise the FEIR, in accordance with CEQA Guidelines, Section 15132.

1.2 Format of the FEIR
This document is organized as follows:

Section 1, Introduction. This section describes CEQA requirements and content of this FEIR.

Section 2, Response to Comments. This section provides a copy of the comment letters received during the public review period. The comment letters have been reproduced and assigned numbers, L1 through L7. Individual comments have been numbered and the letters are followed by responses with references to the corresponding comment number.

Section 3. Revisions to the Draft EIR. This section contains revisions to the DEIR text as a result of the comments received by agencies and interested persons as described in Section 2 subsequent to release of the DEIR for public review. The City of Anahe im (City) staff has reviewed this material and determined that none of this material constitutes the type of significant new information that requires recirculation of the DEIR for further public comment under CEQA Guidelines Section 15088.5. None of this new material indicates that the project will result in a Response to Comments 1-2 November 2025
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significant new environmental impact not previously disclosed in the DEIR. Additionally, none of this material indicates that there would be a substantial increase in the severity of a previously identified environmental impact that will not be mitigated, or that there would be any of the other circumstances requiring recirculation described in Section 15088.5.

1.3 CEQA Requirements Regarding Comments and Responses
CEQA Guidelines Section 15204 (a) outlines parameters for submitting comments, and reminds persons and public agencies that the focus of review and comment of DEIRs should be “on the sufficiency of the document in identifying and analyzing possible impacts on the environment and ways in which significant effects of the project might be avoided or mitigated. Comments are most helpful when they suggest additional specific alternatives or mitigation measures that would provide better ways to avoid or mitigate the significant environmental effects. At the same time, reviewers should be aware that the adequacy of an EIR is determined in terms of what is reasonably feasible. …CEQA does not require a lead agency to conduct every test or perform all research, study, and experimentation recommended or demanded by commenters. When responding to comments, lead agencies need only respond to significant environmental issues and do not need to provide all information requested by reviewers, as long as a good faith effort a t full disclosure is made in the EIR.”
CEQA Guidelines Section 15204 (c) further advises, “Reviewers should explain the basis for their comments, and should submit data or references offering facts, reasonable assumptions based on facts, or expert opinion supported by facts in support of the comments. Pursuant to Section 15064, an effect shall not be considered significant in the absence of substantial evidence.” Section 15204 (d) also states, “Each responsible agency and trustee agency shall focus its comments on environmental information germane to that agency’s statutory responsibility.” Section 15204 (e) states, “This section shall not be used to restrict the ability of reviewers to comment on the general adequacy of a document or of the lead agency to reject comments not focused as recommended by this section.”
In accordance with Public Resources Code Section 21092.5, copies of the written responses to public agencies will be forwarded to those agencies at least 10 days prior to certifying the environmental impact report. The responses will be forwarded with copi es of this FEIR, as permitted by CEQA, and will conform to the legal standards established for response to comments on DEIR.

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Section 2 Response to Comments
Section 15088 of the CEQA Guidelines requires the lead agency (City of Anaheim) to evaluate comments on environmental issues received from public agencies and interested parties who reviewed the DEIR and prepare written responses.

Comment letters and specific comments are given letters and numbers for reference purposes.

Where sections of the DEIR are excerpted in this document, the sections are shown indented.

Changes to the DEIR text are shown in underlined text for additions and strikeout for deletions.

The following is a list of agencies and persons that submitted comments on the DEIR during the public review period.

List of Public Comments
No. Reference Commenting Agency/Interested Parties Date of Comment Page No.

Letter 1 (L1) California Department of Transportation September 4, 2025 2-3 Letter 2 (L2) Orange County Public Works September 8, 2025 2-9 Letter 3 (L3) Irvine Ranch Water District September 5, 2025 2-20 Letter 4 (L4) City of Yorba Linda September 5, 2025 2-23 Letter 5 (L5) Anaheim Real Estate Partners, LLC September 5, 2025 2-25 Letter 6 (L6) Juaneno Band of Mission Indians September 8, 2025 2-28 Letter 7 (L7) Shiishongna Tongva Nation Corona Band of
Gabrielino Indians
September 8, 2025 2-32

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Letter 1. California Department of Transportation (Caltrans), September 4, 2025 (4 pages)

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Letter 1. Scott Shelley, Branch Chief, Local Development Review-Climate Change- Transit Grants, Caltrans District 12, September 4, 2025 L1-1 Comment acknowledged. No response is required.

L1-2 Comment acknowledged. No response is required.

L1-3 Comment noted. The project includes wayfinding signage, although details and content have not been determined. It is anticipated that wayfinding signage would include various nearby key locations, including, Anaheim Regional Transportation Intermodal Center (ARTIC), and other nearby transit locations. It should be noted that there are no transit stops within the project limits. Therefore, the project would not affect existing transit stops or their operations.

L1-4 Comment acknowledged. The project construction would adhere to the City of Anaheim’s and other applicable jurisdiction’s standard construction conditions, including providing appropriate detours and safety measures and prioritize the mobility, access, and safety of bicyclists, pedestrians, and transit, as required. If any sidewalks or bike lanes need to be closed during construction, all closures and detours will be clearly signed, as required. The project would not require closure of any vehicle and bicycle share travel lanes. Therefore, the use of both May Use Full Lane” (MUTCD R4 -11) and “Share the Road” (W16- 1P) signage is not applicable.

L1-5 The Draft EIR, Chapter 2, Project Description, indicates that the project site extends from Orangewood Avenue north to Ball Road, and that SR-57 crosses the Santa Ana River. The project involves the existing Santa Ana River Trail and Santa Ana River channe l, and would not affect any vehicular travel lanes or traffic, other than the existing maintenance access roads along the west and east embankments that are restricted to the general public.

These access roads are not used for goods movement, and the project would have no adverse impact on the regional goods movement or freight network. Therefore, a freight network context section and maps of nearby state and local truck routes are not needed to address environmental impacts resulting from the project.

L1-6 The comment asserts that the EIR does not address the displacement of freight -reliant industrial uses currently on-site or the long-term regional implications of converting former employment and warehouse space to recreational uses. The project involves th e existing Santa Ana River Trail and Santa Ana River channel, and would not affect any vehicular travel lanes or traffic, other than the existing maintenance access roads along the west and east embankments that are restricted to the general public. These access roads are not used for goods movement, and the project would have no adverse impact on the regional goods movement or freight network. There are no freight- reliant industrial uses on-site, and the project would not displace any industrial uses or convert former employment and Response to Comments 2-8 November 2025
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warehouse space to recreational uses. Therefore, a discussion of any potential indirect impacts on freight capacity or local goods distribution is not required, and not applicable.

L1-7 The comment asserts that the EIR does not consider how site design might preserve emergency access or ensure continuity of freight and delivery services along SR-57 during a natural disaster and requests to add freight resilience strategies into the enviro nmental analysis. As stated in responses to L1 -5 and L1-6, the project involves the existing Santa Ana River Trail and Santa Ana River channel, and would not affect any vehicular travel lanes or traffic, other than the existing maintenance access road s along the west and east embankments that are restricted to the general public. The bridges and undercrossing proposed by the project are for pedestrians and bicycles only, and would have no adverse impact on goods movement along SR-57 and/or Ball Road. The project would improve the SART network, therefore, move cyclists away from existing roadways that have shared lane with vehicle. Therefore, the project would likely have positive impacts to arterials and interchanges near SR-57. Adding freight resilience strategies in the DEIR is not necessary.

L1-8 As indicated in responses to L1 -5 through L1- 7, the project does not involve the displacement of industrial uses or changes to any roadways that support freight movement.

Therefore, consistency checks with key freight documents —such as SCAG’s Connect SoCal 2024 Goods Movement Appendix, the Caltrans Freight Mobility Plan (2020), and the Caltrans District 12 Freight Summary (2023)—are not needed. The project would shift bicycles and pedestrians off roadways by providing a separate trail from vehicular tr affic and would therefore minimize land use conflicts. A freight policy consistency table or narrative describing how the project aligns with regional and statewide goals for goods movement—particularly with respect to minimizing land use conflicts, preserving last-mile access, and ensuring long -term goods delivery functionality in mixed -use areas—would not be necessary.

L1-9 Comment acknowledged. The City will continue to coordinate with Caltrans Planning regarding the timeframe in relation to the upcoming LA Olympic 2028 event.

L1-10 Comment acknowledged. The City will continue to coordinate with Caltrans regarding the encroachment permit and will disclose all utility work prior to permit submittal.

L1-11 Comment acknowledged. The City will submit all required plans and environmental documents in coordination with, and as required by, Caltrans.

L1-12 Comment acknowledged. The City will submit all applications and associated documents/plans as specified by the comment.

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Letter 2. Orange County Public Works, September 8, 2025 (5 pages)

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Letter 2. Virginia Gomez, Senior Planner, OC Public Works /OC Development Services, September 8, 2025
L2-1 The Hydrology Report in DEIR Appendix G has been updated and is included as Appendix A of this Final EIR. The upstream impoundment is described as having a depth of up to approximately 8 feet. This description was revised on pages 3- 4 and 6- 1 of the update d Appendix G.

The proposed diversion pump stations used for dry weather runoff diversion away from the impoundment will have gravity pipes connecting the storm drains to the diversion pump station with 8” diameter pipes. Discharge forcemains from the diversion pump stat ions to the point of discharge will be between 6” to 8” diameter. The discharge forcemain from the Collins Channel diversion pump station travels approximately 2,400 LF south along the east bank of the Santa Ana River ( SAR). Alignment varies but can be gre ater than 3 feet from the top of the east embankment, within Orange County Flood Control District (OCFCD) property. The depths of the gravity pipes are dictated by the depth of the storm drain they are diverting from while the forcemains have more flexibility on the depth of the pipe; however, all pipes are planned to be less than 20 feet deep. Proposed locations of the diversions stations and pipelines have been coordinated with the existing utilities that have been identified in the area.

It is intended for the majority of the pipelines and pump stations to be located within OCFCD property boundaries, while the systems themselves are owned and operated by their respective cities (i.e. City of Anaheim and City of Orange). There are small lengths of pipe that may be located within County of Orange property and City of Anaheim property, and one diversion pump station on the west bank north of Katella may be located within the property owned by OCVIBE.

Proposed locations and design of the diversion pump station pipelines will be reviewed and approved by OCFCD.

L2-2 The updated A ppendix G , Hydrology Report, provides details on the locations of the outfalls contributing to the impoundment areas/ project reach. Additional details of the diversions/ pump stations will be included in design documents. The proposed storm drain pump stations are for dry weather flow control only and are not intended to impound or divert actual stormwater flows. The diversion structures will not impede upstream flows and will be enclosed, preventing vector control issues. The details of the dry weather diversion structures and pump stations will be reviewed and approved by the city of Anaheim, the city of Orange, OCFCD, and Orange County Public Works (OCPW) prior to construction, with ultimate ownership and operations to be by the respective cities.

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L2-3 Collins Channel has been evaluated as a part of Appendix G. The existing drainage capacity is not impacted by inflatable dams. Additional analysis will be completed and details will be provided to OCPW for their review and approval in future design documents for the proposed Collins Channel impoundment. The deflation scenario with the 6” nappe and its effect on water surface elevation in Collins Channel will be further studied, and deflation operation scenarios determined , so as not to cause any upstream impacts to subregional and local drainage systems.

The Chantilly Channel drains through the former OCWD Ball Road basin and into the Santa Ana River upstream of the proposed impounded normal water surface. Chantilly and all storm drains in the project reach will be further evaluated as necessary to ensure the project will not impact upstream drainage.

L2-4 Comment acknowledged. As described in DEIR Section 2.5.1, approval of Section 408 Permit from USACE will be required.

L2-5 Comment acknowledged. OCFCD will not be responsible for ensuring the public’s use of the OC River Walk project area is safe. The City of Anaheim would be required to enter into a separate Maintenance and Operations Agreement with the City of Orange, County of Orange, and Orange County Water District for the long-term maintenance and operation of the project pursuant to Mitigation Measure HYD-1.

L2-6 Comment acknowledged. As described in DEIR Section 2.5.1, approval of Section 408 Permit from USACE will be required. Additionally, the City of Anaheim would be required to enter into a separate Maintenance and Operations Agreement with the City of Orange, County of Orange, and Orange County Water District for the long- term maintenance and operation of the project pursuant to Mitigation Measure HYD-1.

L2-7 The Operation and Maintenance document will layout the responsibility of the operator in coordinating with downstream facilities. The operation and maintenance document will be reviewed and approved by OCFCD. The River Walk impoundments will be operated by OCWD, which has operated the existing Imperial and Five Coves inflatable dams for over 30 years within the SAR.

Scour directly downstream of the impoundments will be analyzed in future reports and additional erosion countermeasures may be included. These design reports and plans will be reviewed and approved by OCFCD.

L2-8 The Army Corps of Engineers (USACE) has used soil cement for embankment and levee protection on numerous projects. Soil Cement design specifications are detailed by the USACE in EM 1110- 2-1913. Soil Cement design will be reviewed and approved by Response to Comments 2-16 November 2025
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USACE as part of the 408 and 404 permitting processes. It will also be reviewed and approved by OCFCD.

L2-9 Preparation of the Operation, Maintenance, Repair, Replacement, and Rehabilitation (OMRR&R) is informed by the USACE. USACE will be involved in the project through the 404 and 408 permits, all O&M documents will be reviewed and approved by USACE, OCFCD, and OCPW.

L2-10 The City of Anaheim would be required to enter into a separate Maintenance and Operations Agreement with the City of Orange, County of Orange, and Orange County Water District for the long- term maintenance and operation of the project pursuant to Mitigation Measure HYD -1. As stated in Mitigation Measure HYD -1, the Maintenance and Operations Agreement (MOA) will include at a minimum, operations responsibilities related to access control, hours of operation, public use rules (including, but not limited to, posting signage for hours, allowed uses, and prohibited activities), security and public safety (including, but not limited to, law enforcement coordination, patrolling duties, transient management, and emergency response protocols), debris removal, pr eparation and implementation of a flood contingency plan, and post storm event procedures.

L2-11 Mitigation Measure HYD-1 requires the City of Anaheim to enter into an MOA with the County of Orange for the ongoing maintenance and operation of the project elements. In order to ensure that the project does not impact OCPW’s daily operations, including maintenance access, safety, and potential conflicts between public users and service vehicles, Mitigation Measure HYD-1 has been modified as follows. This modification does not change the impact analyses or determination related to hydrology and water quality in the Draft EIR and therefore does not constitute significant new information that would require recirculation of the Draft EIR pursuant to CEQA Guidelines Section 15088.5.

Changes to the DEIR text are shown in underlined text for additions and strikeout for deletions.

HYD-1 Prior to the issuance of a discretionary and/or regulatory permit by the City of Orange, County of Orange, or Orange County Water District (“Participating Stakeholders”), the City of Anaheim shall enter into a Maintenance and Operations Agreement (MOA) with the Participating Stakeholder issuing said permit, as applicable. The MOA shall specify roles, responsibilities, performance standards, and communication protocols for the ongoing maintenance and operation of the project elements.

The MOA shall include, at a minimum, the following responsibilities and tasks, or similar, as appropriate for each agreement with the applicable agency:

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• Maintenance responsibilities related to trails, river impoundments and water features, and stormwater and sewer facilities;
• Operations responsibilities related to access control, hours of operation, public use rules (including, but not limited to, posting signage for hours, allowed uses, and prohibited activities), security and public safety (including, but not limited to, law enforcement coordination, patrolling duties, transient management, and emergency response protocols), debris removal, preparation and implementation of a flood contingency plan, and post storm event procedures; • Inspection, monitoring, and reporting responsibilities, including the frequency of routine inspections and water quality monitoring as required by applicable regulatory permits and to address any public health concerns regarding recreational use of the water in the Santa Ana River channel; and • Communication and notification protocols, including construction timing and phasing information for each project element.

The MOA shall include provisions granting the County of Orange (OC) agencies — including, but not limited to, OC Public Works, OC Parks, and OC Sheriff’s Department—vehicular access for monitoring river flows, ensuring public safety, and performing other OC maintenance and operational activities currently conducted by OC agencies, including review and approval of trail improvements and access design.

The MOA shall also address any other items deemed necessary by the Participating Stakeholders to ensure the proper long-term maintenance and operation of the project.

L2-12 Refer to response to L2-11.

L2-13 As required by Mitigation Measure HYD-1, prior to the issuance of a discretionary and/or regulatory permit by the City of Orange, County of Orange, or Orange County Water District (“Participating Stakeholders”), the City of Anaheim will enter into a Maintenance and Operations Agreement (MOA) to ensure that the SART operates and maintained safely. The MOA will address concerns related to security and debris removal, hours of enforcement, and management of unauthorized activity and potential vandalism.

Furthermore, as stated in DEIR Section 4.9.3, PPP T -1, the Santa Ana River Trail will be constructed in compliance with the State Coastal Conservancy's Santa Ana River Parkway & Open Space Plan dated March 14, 2018, or any updates thereof, including trail design principles and guidelines, the California Transportation Department Highway Design Manual's Bikeway Design Criteria, and the design standards of the City of Anaheim, the City of Orange, or other appropriate design standards as required by the applic able approval authority. Therefore, the tail design would not adverse ly affect the current flow Response to Comments 2-18 November 2025
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of traffic on the SART. PPP GEO -3 indicates that all bridges are required to be designed and constructed in accordance with the latest edition of the American Association of State Highway and Transportation Officials Load and Resistance Factor Design Bridg e Design Specifications with California Amendments, the latest versions of the California Department of Transportation Standard Plans, Seismic Desing Criteria, and Geotechnical Manual, as required for various elements of the project, as determined by the a pplicable approval authority. The proposed improvements would improve the trail connections and would be consistent with the City of Anaheim’s Bicycle Master Plan and the City of Orange’s Bikeways Master Plan with minor amendments and improvements are undertaken. As discussed in the response to L2- 11, the proposed trail improvements will be designed to provide OCPW vehicular access to the east side of Santa Ana River, so that existing maintenance and other businesses currently conducted by OCPW can continue.

L2-14 The EIR analysis provides sufficient level of detail consistent with the OC River Walk Conceptual Master Plan and design for the initial stages of the project. The detailed design of the SART and maintenance access roads have not been completed, and the County of Orange, as a stakeholder of the project, would have the responsibility for reviewing and approving the trail access design. Also refer to response to L2 -11 that includes modified Mitigation Measure HYD -1 to ensure that the MOA includes a provision that ensures continued use of access roads by the OC agencies.

L2-15 As required by Mitigation Measure HYD-1, the City of Anaheim and the County of Orange would enter into an MOA that outlines maintenance responsibilities prior to the issuance of a discretionary and/or regulatory permit by the County of Orange.

L2-16 The City of Anaheim will be seeking easements for trail purposes, as required. DEIR Section 2.5.1, Other Agency Approvals, would be modified to include approvals for easements from the landowners, which would be OCFCD and OCWD, depending on the location. This section would also be modified per comment to include necessary approvals and amendments to existing agreements for the management of trail areas.

Per the comment, DEIR Section 2.5.1, Other Agency Approvals, page 2- 19, has been modified as follows:
- OCPW and OCFCD – Approval of encroachment and conditional use permits, construction and general use permits, flood contingency plan review and approval, amendment to OCWD-OCFCD agreement for maximum height of OCWD dams within the SAR, OCFCD permit for modifications to undercrossing. - OCWD and OCFCD – Approval of easement for trail purposes Response to Comments 2-19 November 2025
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- Orange County Parks – Approval of General Use Permit for portions of SART OCFCD’s permits for trail improvements requires review and approval by OC Parks prior to issuance as it pertains to the maintenance responsibilities identified in the County of Orange’s Memorandum of Understanding. Amendments to existing agreements for the management of trail areas from OC Parks to the City of Anaheim may be required.

L2-17 The maintenance and operational responsibilities would occur pursuant to Mitigation Measure HYD-1, as revised per comments by OCPW. Refer to response to L2-11.

L2-18 The operational hours will be coordinated among the City of Anaheim County of Orange, and the City of Orange, as the improvements are implemented in accordance with the MOA as required by Mitigation Measure HYD -1. The City acknowledges that the MOA, and other necessary amendments to County ordinances will require approvals from the County Board of Supervisors.

L2-19 Comment acknowledged. Connections to OC Parks managed areas of the SART will require approval by OC Parks prior to design plan finalization and construction, to ensure maintenance and operational concerns are addressed to the satisfaction of the OC Parks.

Refer to Mitigation Measure HYD-1, as modified, in response to L2-11.

L2-20 As stated in Table 1 -1, NOP Comments Summary, page 1- 15, The project would be operated in compliance with the existing SART operating rules and would therefore only permit Class 1 and Class 2 e-bikes, as stated.

L2-21 Talbert Regional Park is located approximately 1.5 miles upstream of the outlet of the Santa Ana River to the ocean, and approximately 12 miles downstream of the OC River Walk project. Additionally, Talbert Regional Park is at an elevation of approximately 10 feet while OC Riverwalk is at an elevation of approximatley150 feet. The groundwater levels in the areas closest to the ocean, including at Talbert Regional Park, and influenced by the ocean and controlled through OCWD’s Talbert Seawater Intrusi on Barrier. Therefore, impacts to Talbert Regional Pak as a result of the proposed OC River Walk improvements are not anticipated.

In addition to the Talbert Seawater Intrusion Barrier, OCWD operates the existing upstream Five Coves and Imperial rubber dams and T & L levees (from Chapman Ave. to Imperial Hwy.) in the Santa Ana River to manage and maximize groundwater recharge.

OCWD will be responsible for the operation of the proposed OC River Walk impoundments. It is not anticipated that the operational changes upstream as part of the OC River Walk project will result in environmental impacts at Talbert Regional Park.

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Letter 3. Irvine Ranch Water District, September 5, 2025 (2 pages)

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Letter 3. Emily Le, Environmental Compliance Analyst, Irvine Ranch Water District, September 5, 2025
L3-1 The City of Anaheim is working with Orange County Water District (OCWD) to complete the design and construction of the OCWD GWRS turnout at Burris Basin and is planning for the OC River Walk impoundments to provide additional storage and recharge of Groundwater Replenishment System ( GWRS) and Santa Ana River ( SAR) water.

Additionally, the City and OCWD will work through the state permitting required for GWRS water recharged within the SAR Corridor. T he proposed design of the OCWD turnout structure will have discharges to both Burris Basin and the SAR, allowing for GWRS to be discharged into either , with the ability to convey GWRS water to Santiago Basins via the Burris Basin pump station.

The project’s proposed infrastructure will provide additional opportunities for OCWD to increase groundwater recharge of both SAR and GWRS water. Project implementation will improve groundwater recharge and have no impact on Irvine Ranch Water District’s ability to pump groundwater.

L3-2 As stated in the project description, the City will design and construct the rubber dams for the impoundments, and these will become OCWD infrastructure. The system will be operated and maintained by OCWD. The operational protocol assumes that when GWRS water is not available, SAR water will fill the impoundments, or if necessary, the impoundments will be dry. OCPW regularly creates “T” & “L” levees in the Santa Ana River to achieve SAR water infiltration. These T & L levees produce much larger surface areas of evaporation than the two proposed impoundments . As part of the T and L levee operation and maintenance (O&M), OCWD regularly scarifies the soft bottom of the SAR to break up the silt layer that reduces infiltration. A similar riverbed scarification operation will be part of the OC River Walk impoundment O&M program when necessary.

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Letter 4. City of Yorba Linda, September 5, 2025 (1 page)

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Letter 4. Alexis Garcia, Associate Planner, Community Development, Planning Division, City of Yorba Linda, September 5, 2025
L4-1 The comment indicates that the City of Yorba Linda has no concerns at this time, and the City of Anaheim appreciates the input.

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Letter 5. Anaheim Real Estate Partners, LLC (AREP), September 5, 2025 (2 pages)

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Letter 5. Joe O’Toole, Executive Vice President, September 8, 2025 L5-1 The City acknowledges that AREP is a neighbor and stakeholder in the OC River Walk project. Any proposed use of Lot B other than for employee parking for the OCVIBE project requires amendments to the Master and Final Site Plans for the OCVIBE project.

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Letter 6. Juaneno Band of Mission Indians, September 8, 2025 (1 page)

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Letter 6. Joyce Perry, Cultural Resources Director, Juaneño Band of Mission Indians, Acjachemen Nation – Belardes, September 8, 2025 L6-1 The City acknowledges that the Juaneño Band of Mission Indians Acjachemen Nation – Belardes (Acjachemen) does not support the “lead monitor” approach and does not agree with the retention of a single Native American monitor from one tribe. The City also acknowledges that the Acjachemen wish to update the mitigation measure to require monitors from all interested and consulting tribes and that the Acjachemen are open to a rotating schedule.

Mitigation Measure TCR-1 requires a lead Native American monitor to be designated to serve as the point of contact and coordinator for the project during monitoring activities.

The City of Anaheim, as lead agency, determined that the lead monitor approach and the retention of a single Native American monitor constitutes appropriate mitigation to reduce potential impacts to tribal cultural resources to a less- than-significant level. Mitigation Measure TCR-1 has been modified to allow any other federally or state-recognized tribes to review the monitoring logs upon request so that they can participate in the sharing of information.

According to CEQA Guidelines Appendix G, a project would have a significant impact on tribal cultural resources if it would cause a substantial adverse change in the significance of a tribal cultural resource, as defined in Public Resources Code (PRC) Section 21074.

This includes a site, feature, place, cultural landscape (geographically defined in terms of size and scope), sacred place, or object with cultural value to a California Native American tribe, and that is: (1) listed or eligible for listing in the California Register of Historical Resources; or in a local register of historical resources as defined in PRC Section 5020.1(k); or (2) a resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to the criteria set forth in subdivision (c) of PRC Section 5024.1. In applying the criteria set forth in subdivision (c) of PRC Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.

Therefore, under CEQA, the City of Anaheim, as lead agency, has discretion to determine the significance of a tribal cultural resource, provided that its decision is supported by substantial evidence. The City has complied with AB 52 tribal consultation requirements and has consulted with the Acjachemen in good faith.

PRC Section 21080.3.2(b) provides that consultation shall be considered concluded when either of the following occurs:
(1) The parties agree to measures to mitigate or avoid a significant effect, if a significant effect exists, on a tribal cultural resource.

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(2) A party, acting in good faith and after reasonable effort, concludes that mutual agreement cannot be reached.

Accordingly, the City concludes that, despite good faith consultation and reasonable effort, mutual agreement with the Acjachemen cannot be reached.

Note that Mitigation Measure TCR -1 has been modified as shown below to allow other federally and state-recognized tribes to review the monitoring logs. This modification does not change the impact analysis or determination related to tribal cultural resources in the Draft EIR and therefore does not constitute significant new information that would require recirculation of the Draft EIR pursuant to CEQA Guidelines Section 15088.5. Changes to the DEIR text are shown in underlined text for additions and strikeout for deletions.

TCR-1: Prior to the commencement of ground-disturbing activities in any area where soil disturbance is greater than the depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet, and/or where there is documented resource presence, the City of Anaheim (lead agency) shall retain a single Native American Monitor at a time to monitor grading activities as described below. If multiple Tribes have requested monitoring, a lead Native American Monitor shall be designated to serve as the primary monitor. Only one monitor shall be present on -site at any given time during grading activities, unless otherwise agreed upon by the lead agency and the designated lead Native American Monitor.

A. The Native American Monitor shall be from the Gabrieleño Band of Mission Indians – Kizh Nation (Kizh) or Juaneño Band of Mission Indians, Acjachemen Nation – Belardes (Acjachemen). The lead Native American Monitor shall serve as the point of contact and coordinator for the project during monitoring activities.

B. For the purposes of this requirement, “ground- disturbing activity” includes project locations inside the project boundary, excluding off-site work within existing public right- of-way. “Ground-disturbing activity” includes, but is not limited to, demolition, pavement removal, potholing, auguring, grubbing, tree removal, boring, grading, excavation, drilling, and trenching resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activi ties extend into native soils exceeding a depth of 5 feet.

C. The City of Anaheim shall execute a monitoring agreement with the lead Native American Monitor Tribe prior to the earlier of the commencement of any ground-disturbing activity, or the issuance of any permit necessary to commence a ground-disturbing activity.

D. The Native American Monitor shall complete daily monitoring logs that will provide descriptions of the relevant ground- disturbing activities, the type of construction activities performed, locations of ground-disturbing activities, soil types, cultural-related materials, and any other facts, conditions, materials, or discoveries of significance to the Tribe and the lead agency. Monitor logs Response to Comments 2-31 November 2025
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shall identify and describe any discovered Tribal Cultural Resources, including but not limited to Native American cultural and historical artifacts, remains, places of significance, etc., as well as any discovered Native American (ancestral) human remains and burial goods. Copies of monitor logs will be provided to the City and the Kizh and Acjachemen Tribes. Any other federally or state-recognized tribes requesting copies of the monitoring logs shall be provided with the logs by the City.

E. On-site Native American Monitor shall conclude upon the former of the following:
1) Written confirmation from a designated point of contact for the lead agency to the lead Native American Monitor that all ground-disturbing activities resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet on the project site or in connection with the project are complete; or 2) A determination and written notification from the lead Native American Monitor to the lead agency stating that no future planned construction or development activity at the project site has the potential to impact Kizh and Acjachemen Tribal Cultural Resources.

F. Upon discovery of any Tribal Cultural Resources, all construction activities in the immediate vicinity of the discovery shall cease (i.e., not less than the surrounding 50 feet) and shall not resume until the discovered Tribal Cultural Resource has been fully assessed by Kizh and Acjachemen monitors and an archaeologist retained by the lead agency. The Kizh or Acjachemen Tribe shall recover and retain all discovered Tribal Cultural Resources in the form and manner the affected Tribe deems appropriate, in the affected Tribe’s sole discretion, and for any purpose the affected Tribe deems appropriate, including for educational, cultural and historical purposes.

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Letter 7. Shiishongna Tongva Nation Corona Band of Gabrielino Indians, September 8, 2025 (5 page, attachments are included as Appendix B to this Response to Comments)

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Letter 7. Laura Jaime Tribal Anthropologist & Enrolled Member Shiishongna Tongva Nation Corona Band of Gabrielino Indians, September 8, 2025 L7-1 The comment introduces the Shiishongna Tongva Nation and requests that the letter serve as a formal request for government-to-government consultation pursuant to AB 52.

However, AB 52 (Public Resources Code Section 21080.3.1 et seq.) consultation applies only if: (1) the California Native American tribe has previously submitted a written request to the lead agency to be formally notified of proposed projects in the geographic area traditionally and culturally affiliated with the tribe; and (2) the tribe responds in writing within 30 days of receipt of the formal notification and requests consultation.

The Shiishongna Tongva Nation has not previously submitted a written request to the City to be formally notified of projects. Furthermore, in applying the criteria set forth in subdivision (c) of PRC Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe. PRC Section 21073 defines “California Native American tribe” as a Native American tribe located in California that is on the contact list maintained by the Native American Heritage Commission (NAHC) for the purposes of Chapter 905 of the Statutes of 2004. The Shiishongna Tongva Nation is not currently on the contact list maintained by the NAHC , as confirmed by the NAHC and acknowledged by the comment . Therefore Shiishongna Tongva Nation is not a federally or state-recognized tribe that meets the definition under PRC Section 21073 to be eligible for AB 52 consultation.

Based on the reasons discussed above, the City is not required to consult with the Shiishongna Tongva Nation pursuant to AB 52.

L7-2 Refer to response to L7-7.

L7-3 Refer to response to L7-5.

L7-4 Refer to responses L7-8 and L7-10.

L7-5 The comment asserts that the tribal consultation taken by the City is flawed because the City relied on the NAHC list that excluded the Shiishongna Tongva Nation. As discussed in the response to L7- 1, the Shiishongna Tongva Nation did not submit a written request to the City to be formally notified of projects within the geographic area traditionally and culturally affiliated with the tribe. AB 52 specifies that consultation is required only for tribe that has previously submitted such request to the lead agency. Therefore, this is not a critical failure for the City, and the City has complied with the requirements of AB 52.

Note that PRC Section 21073 defines “California Native American tribe” as a Native American tribe located in California that is on the contact list maintained by the Native Response to Comments 2-38 November 2025
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American Heritage Commission for the purposes of Chapter 905 of the Statutes of 2004 (Senate Bill 18).

The City confirmed with Cody Campagne, Staff Service Manager I, Native American Heritage Commission in an email correspondence on September 10, 2025, that the Shiishongna Tongva Nation is not currently on the NAHC’s Contact List, and that there will be no additions to the Contact List until the proposed Draft Contact List Regulations have been approved and implemented by the NAHC. The NAHC has released the Draft Contact List Regulations o n October 23, 2023, and is soliciting comments on the draft through December 12, 2025.

Letters of appreciation from the Cities of Riverside and Corona and other organizations and institutions do not substantiate the claim that the City should have notified the tribe and requested consultation. AB 52 requirements make it clear that the tribal consultation applies only if the California Native American tribe has previously submitted a written request, and the Shiishongna Tongva Nation did not make such request previously.

L7-6 AB 52 established the NAHC and vested it with specified powers and duties, including conducting the Sacred Lands Files check (PRC Section 5097.94), as they have the powers and duties to identify and catalog places of special religious or social significance to Native Americans, and known graves and cemeteries of Native Americans on private lands. The comment asserting that the Sacred Lands File check result from NAHC is meaningless because the Shiishongna Tongva Nation is not included on the NAHC list lacks substantial evidence. No supporting documents were provided with this comment.

L7-7 The Negative Findings Memo (Appendix E to the DEIR) was not prepared solely on the basis of a single-day pedestrian survey or limited to subsurface archaeological deposits. It was also informed by background research and a records search conducted through the California Historic Resources Inventory System (CHRIS) by Donna Beddow, RPA (Registered Professional Archaeologist). In addition, outreach to the tribes identified in the NAHC response letter was conducted prior to making the finding.

No documented archaeological or tribal cultural resources have been identified on or near the project site. California Code of Regulations Section 15064.5 provides guidance for determining the significance of impacts on archaeological and historical resources, and as discussed in Section 4.3, Cultural Resources, no such resources were identified within or near the project site. The references cited in the comments —such as documentation of historical villages near the Santa Ana River, people residing at the San Gabriel Mission, and the Santa Ana River’s role as a prehistoric industrial resource and as part of the Tongva ceramic tradition —do not substantiate that the project site has a high potential for the discovery of archaeological or historic cultural resources pursuant to CCR Section 15064.5, Response to Comments 2-39 November 2025
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nor do they demonstrate how the project would adversely affect such resources. While the comment references Dr. Chester King, mission records from 1776, and Stephen O’Neil’s research, no additional information, reports, or maps were provided to review or verify the relevance of this material. Moreover, The Mexican Potters of Prado by Greenwood and Associates and the U.S. Army Corps of Engineers is not directly relevant to the project, as it pertains to the area behind Prado Dam across the Santa Ana River in Riverside County, within the Rincon Townsite, a recorded cultural resource.

As stated in DEIR Section 4.3, Cultural Resources, the existing riverbed and banks of the Santa Ana River within the project limits have been heavily modified over time on both the east and west sides. The river channel, constructed in 1995, is a trapezoidal soft-bottom channel that is routinely graded for maintenance purposes (e.g., flood control, sediment and erosion management, and stormwater conveyance). Figures 2 -4a through 2- 4d, Existing Project Site Views, show the current conditions of the riverbed, embankments, and adjacent development. As shown, the project site and surrounding areas are already developed, and redevelopment of this area has minimal potential to directly affect documented cultural resources.

Although the project site and its surroundings are heavily disturbed, the DEIR concluded that impacts to previously unidentified subsurface tribal cultural resources could occur if excavation extends into undisturbed native soils. Mitigation Measure TCR -1 has been included to reduce such impacts to a less than significant level.

Note that Mitigation Measure TCR -1 has been modified as shown below to allow other federally and state-recognized tribes to review the monitoring logs. This modification does not change the impact analysis or determination related to tribal cultural resources in the DEIR and therefore does not constitute significant new information that would require recirculation of the Draft EIR pursuant to CEQA Guidelines Section 15088.5. Changes to the DEIR text are shown in underlined text for additions and strikeout for deletions.

TCR-1: Prior to the commencement of ground-disturbing activities in any area where soil disturbance is greater than the depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet, and/or where there is documented resource presence, the City of Anaheim (lead agency) shall retain a single Native American Monitor at a time to monitor grading activities as described below. If multiple Tribes have requested monitoring, a lead Native American Monitor shall be designated to serve as the primary monitor. Only one monitor shall be present on- site at any given time during grading activities, unless otherwise agreed upon by the lead agency and the designated lead Native American Monitor.

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A. The Native American Monitor shall be from the Gabrieleño Band of Mission Indians – Kizh Nation (Kizh) or Juaneño Band of Mission Indians, Acjachemen Nation – Belardes (Acjachemen). The lead Native American Monitor shall serve as the point of contact and coordinator for the project during monitoring activities.

B. For the purposes of this requirement, “ground-disturbing activity” includes project locations inside the project boundary, excluding off -site work within existing public right-of-way. “Ground-disturbing activity” includes, but is not limited to, demolition, pavement removal, potholing, auguring, grubbing, tree removal, boring, grading, excavation, drilling, and trenching resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet.

C. The City of Anaheim shall execute a monitoring agreement with the lead Native American Monitor Tribe prior to the earlier of the commencement of any ground - disturbing activity, or the issuance of any permit necessary to commence a ground- disturbing activity.

D. The Native American Monitor shall complete daily monitoring logs that will provide descriptions of the relevant ground -disturbing activities, the type of construction activities performed, locations of ground-disturbing activities, soil types, cultural-related materials, and any other facts, conditions, materials, or discoveries of significance to the Tribe and the lead agency. Monitor logs shall identify and describe any discovered Tribal Cultural Resources, including but not limited to Native American cultural and historical artifacts, remains, places of significance, etc., as well as any discovered Native American (ancestral) human remains and burial goods. Copies of monitor logs will be provided to the City and the Kizh and Acjachemen Tribes. Any other federally or state-recognized tribes requesting copies of the monitoring logs shall be provided with the logs by the City of Anaheim.

E. On-site Native American Monitor shall conclude upon the former of the following:
1) Written confirmation from a designated point of contact for the lead agency to the lead Native American Monitor that all ground -disturbing activities resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet on the project site or in connection with the project are complete; or
2) A determination and written notification from the lead Native American Monitor to the lead agency stating that no future planned construction or Response to Comments 2-41 November 2025
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development activity at the project site has the potential to impact Kizh and Acjachemen Tribal Cultural Resources.

L7-8 In accordance with AB 52, the City notified the Tribes on the City’s Tribal Consultation list about the project in December 2024, for the government -to-government consultation to determine the potential for T ribal Cultural Resources on site and to inquire if local knowledge of TCR is available about the project site. The City conducted the government- to-government consultation with Andrew Salas from Gabrieleño Band of Mission Indians – Kizh Nation and Joyce Stanfield Perry from Juaneño Band of Mission Indians, Acjachemen Nation. Also, as part of the Cultural Resources Survey Letter Report (Appendix E to the DEIR), outreach to the list of tribes in the N ative American Heritage Commission contact list was conducted to gather information about the project site.

Therefore, it is inaccurate to assert that the significance determination was made without proper tribe-led mitigation.

Furthermore, according to CEQA Guidelines Appendix G, a project would have a significant impact on tribal cultural resources if it would cause a substantial adverse change in the significance of a tribal cultural resource, as defined in Public Resources Code (PRC) Section 21074. This includes a site, feature, place, cultural landscape (geographically defined in terms of size and scope), sacred place, or object with cultural value to a California Native American tribe, and that is: (1) listed or eligible fo r listing in the California Register of Historical Resources; or in a local register of historical resources as defined in PRC Section 5020.1(k); or (2) a resource determined by the lead agency, in its discretion and supported by substantial evidence, to be significant pursuant to the criteria set forth in subdivision (c) of PRC Section 5024.1. In applying the criteria set forth in subdivision (c) of PRC Section 5024.1, the lead agency shall consider the significance of the resource to a California Native American tribe.

PRC Section 21073 defines “California Native American tribe” as a Native American tribe located in California that is on the contact list maintained by the Native American Heritage Response to Comments 2-42 November 2025
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Commission for the purposes of Chapter 905 of the Statutes of 2004. The Shiishongna Tongva Nation is not currently on the contact list maintained by the NAHC.

L7-9 As discussed in response to L7- 7, the Santa Ana River is not a historic or archaeological resource pursuant to CCR Section 15064.5 and not a tribal cultural resource pursuant to PRC Section 21074 and 5024.1.

L7-10 As discussed in response to L7 -8, the City has complied with the AB 52 protocol, and consulted with the appropriate tribes on the City’s AB 52 consultation list. Under CEQA, the City of Anaheim, as lead agency, has discretion to determine the significance of a tribal cultural resource, provided that its decision is supported by substantial evidence. The negative result from the SLF by NAHC, conclusion made in the Cultural Resources Survey Memo, and the City’s consultation pursuant to AB 52 supports the City’s determination that while there is no currently identified TCR in the project area, future subsurface disturbances could result in potential discovery of TCR, therefore, Mitigation Measure TCR-1 has been provided. While no tribal monitoring from the Shiishongna Tongva Nation is required under CEQA, the mitigation has been revised as below to accommodate participation from other interested federally or state -recognized tribes by reviewing the monitoring logs.

TCR-1: Prior to the commencement of ground-disturbing activities in any area where soil disturbance is greater than the depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet, and/or where there is documented resource presence, the City of Anaheim (lead agency) shall retain a single Native American Monitor at a time to monitor grading activities as described below. If multiple Tribes have requested monitoring, a lead Native American Monitor shall be designated to serve as the primary monitor. Only one monitor shall be present on- site at any given time during grading activities, unless otherwise agreed upon by the lead agency and the designated lead Native American Monitor.

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B. For the purposes of this requirement, “ground-disturbing activity” includes project locations inside the project boundary, excluding off -site work within existing public right-of-way. “Ground-disturbing activity” includes, but is not limited to, demolition, pavement removal, potholing, auguring, grubbing, tree removal, boring, grading, excavation, drilling, and trenching resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet.

C. The City of Anaheim shall execute a monitoring agreement with the lead Native American Monitor Tribe prior to the earlier of the commencement of any ground - disturbing activity, or the issuance of any permit necessary to commence a ground- disturbing activity.

D. The Native American Monitor shall complete daily monitoring logs that will provide descriptions of the relevant ground -disturbing activities, the type of construction activities performed, locations of ground-disturbing activities, soil types, cultural-related materials, and any other facts, conditions, materials, or discoveries of significance to the Tribe and the lead agency. Monitor logs shall identify and describe any discovered Tribal Cultural Resources, including but not limited to Native American cultural and historical artifacts, remains, places of significance, etc., as well as any discovered Native American (ancestral) human remains and burial goods. Copies of monitor logs will be provided to the City and the Kizh and Acjachemen Tribes. Any other federally or state-recognized tribes requesting copies of the monitoring logs shall be provided with the logs by the City of Anaheim.

E. On-site Native American Monitor shall conclude upon the former of the following:
1) Written confirmation from a designated point of contact for the lead agency to the lead Native American Monitor that all ground -disturbing activities resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet on the project site or in connection with the project are complete; or
2) A determination and written notification from the lead Native American Monitor to the lead agency stating that no future planned construction or development activity at the project site has the potential to impact Kizh and Acjachemen Tribal Cultural Resources.

F. Upon discovery of any Tribal Cultural Resources, all construction activities in the immediate vicinity of the discovery shall cease (i.e., not less than the surrounding 50 Response to Comments 2-44 November 2025
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feet) and shall not resume until the discovered Tribal Cultural Resource has been fully assessed by Kizh and Acjachemen monitors and an archaeologist retained by the lead agency. The Kizh or Acjachemen Tribe shall recover and retain all discovered Tribal Cultural Resources in the form and manner the affected Tribe deems appropriate, in the affected Tribe’s sole discretion, and for any purpose the affected Tribe deems appropriate, including for educational, cultural and historical purposes.

L7-11 PRC Section 21080.3.1(a) states the following: the Legislature finds and declares that California Native American tribes traditionally and culturally affiliated with a geographic area may have expertise concerning their tribal cultural resources. As stated in multiple responses to comments L7-1 through L7-10 above, PRC Section 21073 defines “California Native American tribe” as a Native American tribe located in California that is on the contact list maintained by the Native American Heritage Commission for the purposes of Chapter 905 of the Statutes of 2004. The Shiishongna Tongva Nation is not listed on the NAHC contact list. Therefore, consultation with the Shiishongna Tongva Nation is not warranted under PRC Section 21080.3.1.

L7-12 The project’s cultural resources report, which includes the archaeological survey by a qualified archaeologist, is included as Appendix E to the DEIR, and the geotechnical report is included as Appendix F to the DEIR. The Draft OC River Walk Conceptual Master Plan is available for public review on the City’s webpage:
https://www.anaheim.net/DocumentCenter/View/65823/2025-06- 30_OCRW_Conceptual-Master-Plan_web_sm?bidId=
L7-13 As stated above, the comment did not provide significant new information pursuant to CEQA Guidelines Section 15088.5 and revision to significance determination for the TCR is not warranted.

L7-14 Refer to response to L7-10.

L7-15 The City is required to comply with PRC Section 21084.3, which requires public agencies to avoid damaging effects to any tribal cultural resources, when feasible. Additionally, Mitigation Measure TCR-1, as modified (refer to response to L7-10), has been determined adequate by the City, in consultation with the Kizh Nation and Juaneño Band of Mission Indians, Acjachemen Nation – Belardes, California Native American tribes located in California that are on the contact list maintained by the Native American Heritage Commission.

L7-16 As discussed in response to L7 -7, the commenter did not provide key academic or archaeological studies to substantiate that the project site contains significant archaeological, historic, or tribal cultural resources. In addition, as discussed in multiple Response to Comments 2-45 November 2025
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responses to comments L7-1 through L7-10 above, the Shiishongna Tongva Nation is not a federally or state-recognized tribe that meets the definition under PRC Section 21073 to be eligible for AB 52 consultation. Therefore, the City of Anaheim is not required to conduct consultation with the tribe.

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Section 3 Revisions to the Draft EIR

3.1 Introduction
This section contains revisions to the DEIR based upon additional or revised information required to prepare a response to a specific comment. This section also includes additional mitigation measures to fully respond to commenter concerns as well as provide additional clarification to mitigation requirements included in the DEIR. The provision of these modified mitigation measures does not alter any impact significance conclusions as disclosed in the DEIR. Changes made to the DEIR are identified here in st rikeout text to indicate deletions and in underlined to signify additions. The Mitigation Monitoring Program No. 398, with updated text, is contained in Appendix C.

3.2 DEIR Revisions in Response to Written Comments
Page ES-14 and ES-15, Section ES. 5. Summary of Environmental Impacts and Mitigation Measures, Table ES-2. Summary of Environmental Impacts and Mitigation Measures.

Section 4.7, Hydrology and Water Quality
Threshold BIO-1:

Candidate,
Sensitive, or
Special-Status
Species
Potentially
significant.

BIO-4: Least Bell’s Vireo and Yellow Warbler Pre-
Construction Surveys. For any work proposed in or near
suitable habitat between February 15 and August 15
(March 15 and September 15 for least Bell’s vireo), a pre- construction survey for least Bell’s vireo and yellow
warbler shall be performed to reaffirm the presence and extent of occupied habitat. The survey shall occur within five days prior to the start of construction. The pre-
construction survey area for the species shall encompass all potentially suitable habitat within the project work zone and a 300-foot survey buffer. The pre construction survey shall be performed to the satisfaction of the City of
Anaheim project manager (or their designee) by a qualified biologist familiar with the species. The results of the pre- construction survey shall be submitted in a report to the City of Anaheim project manager (or their designee) for review and approval before initiating any construction
activities. If least Bell’s vireo or yellow warbler are detected, a minimum 300-foot buffer delineated by orange biological fencing shall be established around the detected species. In addition, on-site noise reduction/attenuation techniques shall be incorporated, as appropriate, to avoid impacts to breeding least Bell’s vireo and yellow warbler from elevated construction noise levels during the
breeding season. The City of Anaheim project manager (or their designee) shall have the discretion to modify the buffer width depending on site-specific conditions. In
addition, noise monitoring may be required to ensure that the elevated construction noise levels are appropriately attenuated at the edge of occupied habitat to a level that is not expected to adversely affect nesting bird behavior (i.e., not to exceed an hourly average of 60 A-weighted
Less than
significant.

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decibels or ambient whichever is greater, at the edge of occupied habitat).

Page ES-17 and ES-18, Section ES. 5. Summary of Environmental Impacts and Mitigation Measures, Table ES-2. Summary of Environmental Impacts and Mitigation Measures.

Section 4.7, Hydrology and Water Quality
Thresholds HYD-
1 and HYD-3
(polluted runoff):

Water Quality
Standards and
Polluted Runoff
Potentially
significant.

HYD-1: Prior to the issuance of a discretionary and/or
regulatory permit by the City of Orange, County of
Orange, or Orange County Water District
(“Participating Stakeholders”), the City of Anaheim
shall enter into a Maintenance and Operations
Agreement (MOA) with the Participating Stakeholder
issuing said permit, as applicable. The MOA shall
specify roles, responsibilities, performance standards, and communication protocols for the ongoing
maintenance and operation of the project elements.

The MOA shall include, at a minimum, the following
responsibilities and tasks, or similar, as appropriate
for each agreement with the applicable agency:
• Maintenance responsibilities related to trails,
river impoundments and water features, and
stormwater and sewer facilities;
• Operations responsibilities related to access
control, hours of operation, public use rules
(including, but not limited to, posting signage for
hours, allowed uses, and prohibited activities),
security and public safety (including, but not
limited to, law enforcement coordination,
patrolling duties, transient management, and
emergency response protocols), debris removal,
preparation and implementation of a flood
contingency plan, and post storm event
procedures;
• Inspection, monitoring, and reporting
responsibilities, including the frequency of routine
inspections and water quality monitoring as
required by applicable regulatory permits and to
address any public health concerns regarding
recreational use of the water in the Santa Ana
River channel; and
• Communication and notification protocols,
including construction timing and phasing
information for each project element.

The MOA shall include provisions granting the County
of Orange (OC) agencies—including, but not limited
to, OC Public Works, OC Parks, and OC Sheriff’s
Department—vehicular access for monitoring river
flows, ensuring public safety, and performing other
OC maintenance and operational activities currently
conducted by OC agencies, including review and
approval of trail improvements and access design.

Less than
significant.

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The MOA shall also address any other items deemed
necessary by the Participating Stakeholders to ensure
the proper long-term maintenance and operation of
the project.

Page ES-19 and ES-20, Section ES. 5. Summary of Environmental Impacts and Mitigation Measures, Table ES-2. Summary of Environmental Impacts and Mitigation Measures.

Section 4.10, Tribal Cultural Resources
Threshold TCR-1:

Tribal Cultural
Resources
Potentially
significant
TCR-1: Prior to the commencement of ground-disturbing
activities in any area where soil disturbance is greater than the depth of current foundations present on a
project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet,
and/or where there is documented resource presence,
the City of Anaheim (lead agency) shall retain a single Native American Monitor at a time to monitor grading
activities as described below. If multiple Tribes have
requested monitoring, a lead Native American Monitor
shall be designated to serve as the primary monitor.

Only one monitor shall be present on-site at any given
time during grading activities, unless otherwise agreed upon by the lead agency and the designated lead
Native American Monitor.

A. The Native American Monitor shall be from the
Gabrieleño Band of Mission Indians – Kizh
Nation (Kizh) or Juaneño Band of Mission
Indians, Acjachemen Nation – Belardes
(Acjachemen). The lead Native American Monitor
shall serve as the point of contact and
coordinator for the project during monitoring
activities.

B. For the purposes of this requirement, “ground-
disturbing activity” includes project locations
inside the project boundary, excluding off-site
work within existing public right-of-way. “Ground-
disturbing activity” includes, but is not limited to,
demolition, pavement removal, potholing,
auguring, grubbing, tree removal, boring, grading,
excavation, drilling, and trenching resulting in soil
disturbance exceeding a depth of current
foundations present on a project site, or in areas
where the disturbance activities extend into
native soils exceeding a depth of 5 feet.

C. The City of Anaheim shall execute a monitoring
agreement with the lead Native American Monitor
Tribe prior to the earlier of the commencement of
any ground-disturbing activity, or the issuance of
any permit necessary to commence a ground-
disturbing activity.

D. The Native American Monitor shall complete daily
monitoring logs that will provide descriptions of
the relevant ground-disturbing activities, the type
of construction activities performed, locations of
ground-disturbing activities, soil types, cultural-
Less than
significant
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related materials, and any other facts, conditions,
materials, or discoveries of significance to the
Tribe and the lead agency. Monitor logs shall
identify and describe any discovered Tribal
Cultural Resources, including but not limited to
Native American cultural and historical artifacts,
remains, places of significance, etc., as well as
any discovered Native American (ancestral)
human remains and burial goods. Copies of
monitor logs will be provided to the City and the
Kizh and Acjachemen Tribes. Any other federally
or state-recognized tribes requesting copies of
the monitoring logs shall be provided with the
logs by the City of Anaheim.

E. On-site Native American Monitor shall conclude
upon the former of the following:
1) Written confirmation from a designated point
of contact for the lead agency to the lead
Native American Monitor that all ground-
disturbing activities resulting in soil
disturbance exceeding a depth of current
foundations present on a project site, or in
areas where the disturbance activities extend
into native soils exceeding a depth of 5 feet
on the project site or in connection with the
project are complete; or
2) A determination and written notification from
the lead Native American Monitor to the lead
agency stating that no future planned
construction or development activity at the
project site has the potential to impact Kizh
and Acjachemen Tribal Cultural Resources.

F. Upon discovery of any Tribal Cultural Resources,
all construction activities in the immediate vicinity
of the discovery shall cease (i.e., not less than the
surrounding 50 feet) and shall not resume until the
discovered Tribal Cultural Resource has been fully
assessed by Kizh and Acjachemen monitors and
an archaeologist retained by the lead agency. The
Kizh or Acjachemen Tribe shall recover and retain
all discovered Tribal Cultural Resources in the
form and manner the affected Tribe deems
appropriate, in the affected Tribe’s sole discretion,
and for any purpose the affected Tribe deems
appropriate, including for educational, cultural and
historical purposes.

Page 2 ends

has been modified in response to comment Letter 2, from Orange County Public Works. • Local
− City of Orange – Approval of encroachment and access permits; minor amendments to the City of Orange General Plan Circulation and Mobility Response to Comments 3-5 November 2025
OC River Walk Project EIR No. 357
Element and the Bikeways Master Plan may be necessary as improvements are undertaken.
− OCPW and OCFCD – Approval of encroachment and conditional use permits, construction and general use permits, flood contingency plan review and approval, amendment to OCWD-OCFCD agreement for maximum height of OCWD dams within the SAR, OCFCD permit for modifications to undercrossing − OCWD and OCFCD – Approval of easement for trail purposes - Orange County Parks – Approval of General Use Permit for portions of SART OCFCD’s permits for trail improvements requires review and approval by OC Parks prior to issuance as it pertains to the maintenance responsibilities identified in the County of Orange’s Memorandum of Understanding.

Amendments to existing agreements for the management of trail areas from OC Parks to the City of Anaheim may be required.
- Pages 2-31, 2-33, 2-35, 2-37, 2-43, 2-47, 2-49, 2-51, 2-53, 2-57, and 2-59, Figures 2- 4a through 2-4d, 2-7, 2-8a through 2-8d, 2-10 and 2-11. Minor corrections to the reference sources and cleanup of the figures were made. See Appendix D for updated figures.

Figures 2-4a through 2-4d, Existing Project Site Views: The source for all four figures was updated from “OC River Walk Conceptual Maser Plan 2024” to “OC River Walk Vision Plan, 2024”.

Figure 2-7, Proposed Impoundments and Trail Improvements : The out of place text “Source:

Pacific Advanced Civil Engineering Inc. (PACE)” was removed.

Figures 2-8a thru 2-8d, Proposed Improvements: The source for all four figures was updated from “PACE Advanced Water Engineering 2025” to “Pacific Advanced Civil Engineering Inc. (PACE), 2025”.

Figure 2-10, Trail Circulation System: The source was updated from “PACE Advanced Water Enginerring 2024” to “OC River Walk Vision Plan, 2024”
Figure 2-11, Project Rendering – South of Cerritos River Access: The source was updated from “PACE Advanced Water Enginerring 2024” to “OC River Walk Conceptual Master Plan, 2025”.

Page 4 ends

The following mitigation measure has been modified to clarify the implementation timing.

BIO-4 Least Bell’s Vireo and Yellow Warbler Pre -Construction Surveys. For any work proposed in or near suitable habitat between February 15 and August 15 (March 15 and September 15 for least Bell’s vireo), a pre -construction survey for least Bell’s vireo and yellow warbler shall be performed to reaffirm the presence and extent of occupied Response to Comments 3-6 November 2025
OC River Walk Project EIR No. 357
habitat. The survey shall occur within five days prior to the start of construction. The pre-construction survey area for the species shall encompass all potentially suitable habitat within the project work zone and a 300-foot survey buffer. The pre construction survey shall be performed to the satisfaction of the City of Anaheim project manager (or their designee) by a qualified biologist familiar with the species. The results of the pre-construction survey shall be submitted in a report to the City of Ana heim project manager (or their designee) for review and approval before initiating any construction activities. If least Bell’s vireo or yellow warbler are detected, a minimum 300 -foot buffer delineated by orange biological fencing shall be established around the detected species. In addition, on- site noise reduction/attenuation techniques shall be incorporated, as appropriate, to avoid impacts to breeding least Bell’s vireo and yellow warbler from elevated construction noise levels during the breeding seas on. The City of Anaheim project manager (or their designee) shall have the discretion to modify the buffer width depending on site-specific conditions. In addition, noise monitoring may be required to ensure that the elevated construction noise levels are appropriately attenuated at the edge of occupied habitat to a level that is not expected to adversely affect nesting bird behavior (i.e., not to exceed an hourly average of 60 A -weighted decibels or ambient whichever is greater, at the edge of occupied habitat).

Page 4 ends

HYD-1 and HYD-3c. The following text has been modified in response to comment Letter 2, from Orange County Public Works.

The MOA shall include, at a minimum, the following responsibilities and tasks, or similar, as appropriate for each agreement with the applicable agency:
• Maintenance responsibilities related to trails, river impoundments and water features, and stormwater and sewer facilities;
• Operations responsibilities related to access control, hours of operation, public use rules (including, but not limited to, posting signage for hours, allowed uses, and prohibited activities), security and public safety (including, but not limited to, law enforcement coordination, patrolling duties, transient management, and Response to Comments 3-7 November 2025
OC River Walk Project EIR No. 357
emergency response protocols), debris removal, preparation and implementation of a flood contingency plan, and post storm event procedures; • Inspection, monitoring, and reporting responsibilities, including the frequency of routine inspections and water quality monitoring as required by applicable regulatory permits and to address any public health concerns regarding recreational use of the water in the Santa Ana River channel; and • Communication and notification protocols, including construction timing and phasing information for each project element.

The MOA shall also address any other items deemed necessary by the Participating Stakeholders to ensure the proper long-term maintenance and operation of the project.

Page 4 ends

text has been modified in response to comment Letter 6 from Juaneño Band of Mission Indians, Acjachemen Nation – Belardes and from Letter 7, Shiishongna Tongva Nation.

TCR-1: Prior to the commencement of ground -disturbing activities in any area where soil disturbance is greater than the depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet, and/or where there is documented resource presence, the City of Anaheim (lead agency) shall retain a single Native American Monitor at a time to monitor grading activities as described below. If multiple Tribes have requested monitoring, a lead Native American Monitor shall be designated to serve as the primary monitor. Only one monitor shall be present on- site at any given time during grading activities, unless otherwise agreed upon by the lead agency and the designated lead Native American Monitor.

B. For the purposes of this requirement, “ground-disturbing activity” includes project locations inside the project boundary, excluding off -site work within existing public right-of-way. “Ground-disturbing activity” includes, but is not limited to, demolition, pavement removal, potholing, auguring, grubbing, tree removal, Response to Comments 3-8 November 2025
OC River Walk Project EIR No. 357
boring, grading, excavation, drilling, and trenching resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet.

C. The City of Anaheim shall execute a monitoring agreement with the lead Native American Monitor Tribe prior to the earlier of the commencement of any ground - disturbing activity, or the issuance of any permit necessary to commence a ground- disturbing activity.

D. The Native American Monitor shall complete daily monitoring logs that will provide descriptions of the relevant ground -disturbing activities, the type of construction activities performed, locations of ground-disturbing activities, soil types, cultural-related materials, and any other facts, conditions, materials, or discoveries of significance to the Tribe and the lead agency. Monitor logs shall identify and describe any discovered Tribal Cultural Resources, including but not limited to Native American cultural and historical artifacts, remains, places of significance, etc., as well as any discovered Native American (ancestral) human remains and burial goods. Copies of monitor logs will be provided to the City and the Kizh and Acjachemen Tribes. Any other federally or state-recognized tribes requesting copies of the monitoring logs shall be provided with the logs by the City of Anaheim.

E. On-site Native American Monitor shall conclude upon the former of the following:
1) Written confirmation from a designated point of contact for the lead agency to the lead Native American Monitor that all ground -disturbing activities resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet on the project site or in connection with the project are complete; or
2) A determination and written notification from the lead Native American Monitor to the lead agency stating that no future planned construction or development activity at the project site has the potential to impact Kizh and Acjachemen Tribal Cultural Resources.

F. Upon discovery of any Tribal Cultural Resources, all construction activities in the immediate vicinity of the discovery shall cease (i.e., not less than the surrounding 50 feet) and shall not resume until the discovered Tribal Cultural Resource has been fully assessed by Kizh and Acjachemen monitors and an archaeologist retained by the lead agency. The Kizh or Acjachemen Tribe shall recover and retain all discovered Tribal Cultural Resources in the form and manner the affected Tribe deems appropriate, in Response to Comments 3-9 November 2025
OC River Walk Project EIR No. 357
the affected Tribe’s sole discretion, and for any purpose the affected Tribe deems appropriate, including for educational, cultural and historical purposes.

Page 8 ends

PACE (Pacific Advanced Civil Engineering). 2025. OC River Walk Conceptual Master Plan. May.

PACE. 2024. OC River Walk Vision Plan.

Appendix A. Updated Hydrology Report

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OC River Walk

Hydrology and Hydraulics
Appendix to OC River Walk EIR

September 2025

Prepared For:

Prepared By:

Pacific Advanced Civil Engineering, Inc.
17520 Newhope Street, Suite 200
Fountain Valley, CA 92708
714-481-7300

Contact Persons:

Mark Krebs, PE
Andrew Ronnau, PhD, PE
Emily Randig, MS, EIT PACE B710

Table of Contents i

Table of Contents

Introduction .............................................................................................................................................. 1 Project Overview ...................................................................................................................................... 1 Study Area Description ........................................................................................................................ 3-1

3.1 Lower Santa Ana River Overview .................................................................................................. 3-1

3.2 OC River Walk Study Area ............................................................................................................. 3-2

3.2.1 Existing Major Elements ......................................................................................................... 3-2

3.2.2 Proposed Major Elements ...................................................................................................... 3-3

3.3 Regulatory Setting .......................................................................................................................... 3-4 Hydrology .............................................................................................................................................. 4-1

4.1 Santa Ana River Flowrates ............................................................................................................ 4-1 HEC-RAS Hydraulic Modeling ............................................................................................................. 5-1

5.1 Summary of HEC-RAS Models ...................................................................................................... 5-1

5.2 HEC-RAS Modeling ....................................................................................................................... 5-1

5.3 Floodplain Hydraulics ..................................................................................................................... 5-2 Inflatable Dams and Operations .......................................................................................................... 6-1

6.1 Inflatable Dams .............................................................................................................................. 6-1

6.1.1 Dry Weather Operation .......................................................................................................... 6-1

6.1.2 Low River Flow Operation ...................................................................................................... 6-2

6.1.3 High River Flow Operation ..................................................................................................... 6-2

6.1.4 Collins Channel ...................................................................................................................... 6-3

6.1.5 Interior Drainage to the Impoundments.................................................................................. 6-3

6.2 Hydraulic Analysis for Rapid Drop of Rubber Dam Impoundments ............................................... 6-4

6.2.1 Hydrology ............................................................................................................................... 6-4

6.2.2 Summary of Results ............................................................................................................... 6-5

6.3 Hydraulic Modeling ......................................................................................................................... 6-6

6.3.1 Modeling Parameters ............................................................................................................. 6-6

6.3.2 HEC-RAS Results .................................................................................................................. 6-6 Pedestrian Bridge Scour Analysis ...................................................................................................... 7-1

7.1 Total Scour Analysis ...................................................................................................................... 7-1

7.1.1 Long-Term Scour ................................................................................................................... 7-1

7.1.2 General Scour ........................................................................................................................ 7-1

7.1.3 Bend Scour ............................................................................................................................. 7-1

7.1.4 Bedform Scour ....................................................................................................................... 7-1

7.1.5 Low-Flow Incisement ............................................................................................................. 7-3

7.1.6 Local Pier Scour ..................................................................................................................... 7-3

7.2 Summary of Total Scour ................................................................................................................ 7-3 OC River Walk Development Impact Analysis ................................................................................... 8-1

8.1 Hydraulic Impacts ........................................................................................................................... 8-1

8.1.1 Depth and Velocity ................................................................................................................. 8-1

8.1.2 Freeboard ............................................................................................................................... 8-1

8.1.3 Scour ...................................................................................................................................... 8-1

8.2 Hydrologic Impacts ......................................................................................................................... 8-1

8.3 Water Quality Changes .................................................................................................................. 8-4

8.4 Human Contact Changes and Impacts .......................................................................................... 8-4 Conclusion ............................................................................................................................................. 9-1 References ................................................................................................................................................... 1

Table of Contents ii

Tables
Table 3-1: Existing Bridge Descriptions ..................................................................................................... 3-2 Table 7-1: General Scour Calculation Method Summary .......................................................................... 7-2 Table 7-2: Summary of Each Scour Component ....................................................................................... 7-3

Figures
Figure 2-1: Project Rendering, SMLA ........................................................................................................... 2 Figure 2-2: Regional Vicinity Map ................................................................................................................. 3 Figure 3-1: Upper and Lower Santa Ana River Watershed ....................................................................... 3-1 Figure 3-2: Five Coves Rubber Dam along the Santa Ana River, Operated by OCWD............................ 3-3 Figure 3-3: Agencies Involved with Approval of OC River Walk ................................................................ 3-5 Figure 4-1: USACE GDM Flow Rates Mapped .......................................................................................... 4-2 Figure 5-1: HEC-RAS Cross Section 71772, T and L Levee Invert “Smoothing” ...................................... 5-2 Figure 5-2: HEC-RAS Workmap ................................................................................................................ 5-3 Figure 6-1: OC River Walk Impoundments ................................................................................................ 6-1 Figure 6-2: Deflation Hydrographs ............................................................................................................. 6-5 Figure 8-1: Existing and Proposed Condition Water Surface Elevation Comparison ................................ 8-2 Figure 8-2: Existing and Proposed Condition Velocity Comparison .......................................................... 8-3

Appendices
Appendix A – USACE GDM Hydrology Documentation
Appendix B – Existing Condition HEC-RAS Output
Appendix C – Proposed Condition HEC-RAS Output
Appendix D – Dam Deflation Scenarios HEC-RAS Output
Appendix E – Existing and Proposed Condition Comparison Tables, Water Surface Elevation and Velocity

OC River Walk Hydrology and Hydraulics 1
Section 1 1 – Introduction and Project Overview
Introduction
The OC River Walk project is a set of planned improvements to a 1.5-mile-long reach of the Santa Ana River along the boundary of the City of Orange a nd City of Anaheim , as shown on Figure 2 -1. PACE analyzed the hydrology and hydraulics on the project reach in existing conditions and in proposed conditions. The results were used to assess hydraulic changes, changes to hydrology, and effects of human contact associated with the proposed project improvements. This report documents the analysis approach, results, and conclusions.

Project Overview
The OC River Walk project plans to improve and revitalize a segment of the Santa Ana River. The project will transform a segment of this regional flood control facility into a community asset. The planned improvements are designed to achieve multiple objectives, including:

• Improving area flood protection
• Increasing access and use
• Adding groundwater recharge
• Improving water quality
• Adding open space
• Augmenting and connecting bike paths and pedestrian paths

The project will be located within the Santa Ana River corridor between the Ball Road and Orangewood Avenue bridge crossings, encompassing an area approximately 450 feet wide by 9,000 feet long. The project site is surrounded by urban development , including Angel Stadium, the Anaheim Regional Transportation Intermodal Center (ARTIC), and the Honda Center (Figure 2-2).

The existing Santa Ana River corridor within the study area generally consists of a trapezoidal cross section with a natural soft bottom and riprap bank lining. The proposed OC River Walk project aims to transform the study area into a community destination by:

• Removing the existing riprap bank lining and replacing it with soil cement stepped terraces • Extending the existing Santa Ana River Trail (SART) bike path • Adding two additional pedestrian bridges across the Santa Ana River • Creating two river impoundments for municipal reuse water that will produce groundwater recharge and facilitate recreation

Hydrology for the project site was taken from the U.S. Army Corps of Engineers (USACE) Design Memorandum for Phase II GDM on the Santa Ana River Mainstem , Volume 3 for the Lower Santa Ana River (USACE, 1988). The general design manual ( GDM) document specifies the design flow rates used for OC River Walk. Hydraulic modeling of the project reach was completed using HEC-RAS to analyze existing and proposed flow depths, velocities, freeboard, and scour. The OC River Walk project conforms with the design goals and function of the SAR described in the 1988 GDM. The OC River Walk project design will be reviewed and permitted by USACE and Or ange County Flood Control District (OCFCD) through the 408 permitting process.

Figure 2-1
Figure 2-2

OC River Walk Hydrology and Hydraulics 3-1
Section 3 – Study Area Description
Study Area Description

3.1 Lower Santa Ana River Overview
The lower Santa Ana River watershed (approximately 200 square miles) runs from Prado Dam to the Pacific Ocean, traversing about 31 miles through the cities of Yorba Linda, Anaheim, Orange, Santa Ana, Fountain Valley, Costa Mesa, and Huntington Beach (Figure 3-1).

Figure 3-1: Upper and Lower Santa Ana River Watershed

The Santa Ana River Mainstem project was proposed by the USACE and authorized in the Water Resources Development Ac t of 1986 to increase the flood stage cap acity of Prado Dam and improve downstream channel conveyance and capacity after a series of floods caused catastrophic damage to the increasingly urbanized areas downstream of Prado Dam in the early 1980s. The proje ct included channelization of the Santa Ana River from Weir Canyon Road to the Pacific Ocean , which involved constructing a levee embankment for flood protection.

The OC River Walk project is located in the USACE Lower Santa Ana River Reach es 5 and 6. Reach 5 spans from Riverview Golf Course to the Orange Freeway (SR 57), and reach 6 spans from the Orange Freeway to Glassell Street. Cross sections of the channel are typically trapezoidal with a soft bottom and stone revetted side slopes between 1V to 1.5H and 1V to 3H. A series of reinforced concrete drop structures ranging in height from 4.5 to 9.7 feet and buried rip rap stabilizer structures are constructed at approximately 2,000 ft intervals. These act to maintain a stable grade and control channel scour within the Lower Santa Ana River channel reach.

Construction of the Santa Ana River levee system was completed in September 1995, and the operation and maintenance of the levee was passed to the Orange County Flood Control District (OCFCD), which is administered by Orange County Public Works (OCPW) . The primary purpose of the levee is for flood control, as it protects over 1 million people (USACE National Structure Inventory, 2023). However, the Orange County Water District (OCWD) also uses the soft -bottom channel of the Santa Ana River to recharge the groundwater basin by impounding water in a series of sand levees (“T and L” levees) that slow water within the Santa Ana River for infiltration and groundwater recharge (OCWD, 2006).

OC River Walk Hydrology and Hydraulics 3-2
Section 3 – Study Area Description

3.2 OC River Walk Study Area
OC River Walk consists of an approximately 90 -acre area that covers both banks of the Santa Ana River.

The project area is bound between Orangewood Avenue and Ball Road within the City of Orange and City of Anaheim.

3.2.1 Existing Major Elements
There are many existing elements within the project study area including six bridges over the Santa Ana River, two drop structures, the Collins Channel tributary, and the levee embankment.

3.2.1.1 Levee Embankment and Bike Path
The levee embankment within the project area consists of rip-rap lined riverbank. The Santa Ana River trail runs along the top of the bank between Orangewood Ave and Katella on the west bank and between Katella Avenue and Ball Road on the east bank . According to the ACOE as-built records, the riverbank protection is comprised of loose and grouted rip-rap at a 2(H):1(V) slope. The channel has a base width ranging from 300- to 320 feet and channel depths ranging from 12 to 18.5 feet. The top of bank freeboard provided is a minimum of 2.5 feet (USACE GDM Volume 3, 1988). Loose riprap along the embankments have d50’s that range from 15 inches to 33 inches with thicknesses of 24 inches to 48 inches, respectively. Embankment areas around the drop structures have grouted rip rap with a d50 of 10 inches and a thickness of 15 inches.

Currently, the Santa Ana River Trail bike path runs along the top of the river embankment. The public is authorized to use the bike path areas for recreational activities. The public is currently not authorized to be within the Santa Ana River channel or on the channel’s grouted rip-rap embankments.

3.2.1.2 Drop Structures
Two reinforced concrete drop structures are located within the study area . The downstream structure is located approximately 350 f eet downstream of the LOSSAN bridge with a drop height of 7.27 f eet. The upstream structure is located approximately 400 feet downstream of the Ball Road bridge with a drop height of 9.15 feet. The drop structures provide energy dissipation and minimize river bed and bank scour. Each structure uses a parabolic curved chute downstream of the crest, two rows of baffle blocks, and a sloping end sill (USACE GDM Volume 3, 1988).

3.2.1.3 Bridges
There are six existing bridges that span the Santa Ana River within the project study location at Orangewood Avenue, State Route (SR) 57 , the Los Angeles-San Diego-San Luis Obispo (LOSSAN) Metrolink bridge, Katella Avenue, the Union Pacific railroad (UPRR), and Ball Road. The relevant hydraulic parameters for each bridge are summarized in Table 3-1.

Table 3-1: Existing Bridge Descriptions

Bridge Name Bridge Deck
Data
Bridge Pier
Data Bridge Undercrossing Notes
Orangewood Ave. Bridge Width = 72 ft 6 piers SART undercrossing on west bank SR 57 Bridge Width = 344 ft 6 piers
SART undercrossing on west bank
and maintenance road undercrossing
on the East bank
LOSSAN Metrolink
Bridge Width = 48 ft 3 piers
SART undercrossing on west bank
and maintenance road undercrossing
on the East bank
Katella Ave. Bridge Width = 130 ft 3 piers
SART undercrossing on west bank
and maintenance road undercrossing
on the East bank

OC River Walk Hydrology and Hydraulics 3-3
Section 3 – Study Area Description
Bridge Name Bridge Deck
Data
Bridge Pier
Data Bridge Undercrossing Notes
UPRR Bridge Width = 18 ft 5 piers SART undercrossing on East bank Ball Road Bridge Width = 80 ft 5 piers
Maintenance road undercrossing on
the West bank and SART
undercrossing on East Bank
*Santa Ana River Trail (SART)

3.2.2 Proposed Major Elements
There are four main improvements related to the OC River Walk project that are within or will interact with the Santa Ana River hydraulics, including:

• Two river impoundments in the Santa Ana River for increased groundwater recharge capabilities • Two non-motorized (pedestrian and bicycle) bridges across the Santa Ana River

o Approximately 400 feet upstream of Orangewood Avenue
o Approximately 800 feet upstream of Katella Avenue

• Riverbank modifications replacing existing riprap with soil cement terraces and steps • Two new SART bike undercrossings

o At the west bank at the ARTIC station
o At the Union Pacific railroad

3.2.2.1 River Impoundments
The water impoundment within the Santa Ana River will be similar to OCWD’s existing rubber dam impoundments currently in place for river flow diversion to groundwater recharge (Figure 3-2). However, instead of being used to divert water to offline basins, the OC River Walk impoundment structures would be installed to crea te semi -permanent water bodies in the Santa Ana River for groundwater recharge.

Identical to the existing OCWD structures, the impoundment structures will lower automatically during large storm events or to drain impounded water when otherwise desired.

Figure 3-2: Five Coves Rubber Dam along the Santa Ana River, Operated by OCWD

OC River Walk Hydrology and Hydraulics 3-4
Section 3 – Study Area Description

The first impoundment will be located upstream of the LOSSAN bridge crossing and create about 23 acres of water surface, with a depth up to approximately 8 feet at the location of the impoundment structure. The second impoundment location will be upstream of the Orangewood Avenue bridge crossing and create about 14.4 acres of water surface, with an impoundment depth up to 10 feet at the location of the dam structure.

3.2.2.2 Pedestrian Bridges
Two new pedestrian bridges are proposed over the Santa Ana River to facilitate pedestrian and bicycle access and to connect the west and east banks of the SART. The first bridge crossing would be located near the Honda Center, approximately 800 feet upstream of Katella Ave nue. The bridge is proposed to have three piers and a width of 35 feet. The second bridge would be approximately 400 feet upstream of Orangewood Avenue, across from Angel Stadium. The pedestrian bridge is proposed to have one pier and a width of 16 feet.

3.2.2.3 River Embankment Modifications
The embankments on both sides of the Santa Ana River will be transformed by removing the existing riprap and adding stepped terraces, new soil cement banks, and riverbank planters. The proposed improvements include changing the existing riprap bank slope of 2H:1V to a soil cement slope of 1.5H:1V. The proposed riverbank modifications will maintain river flood control hydraulic capacity and bank stability.

The public will access the terraced and stepped embankments in the proposed condition. OCFCD will review and approve project elements providing public access to the Santa Ana River and ensure public use of OC River Walk Project area is safe.

3.3 Regulatory Setting
To receive regulatory approval and obtain required permits for the OC River Walk impoundments, the project will need to meet the requirements of the following key agencies and regulatory programs:

1. The City of Anaheim for the project’s California Environmental Quality Act (CEQA) approval

2. Amendment of existing California Division of Drinking Water (DDW) reuse permit to impound OCWD’s advanced treated recycled water and use for groundwater recharge

3. Amendment of existing National Pollutant Discharge Elimination System (NPDES) Permit (of which the DDW permit is a subpart)

4. California Department of Fish and Wildlife (CDFW) Section 1602 notification of construction activity in the vicinity of a river

5. U.S. Army Corps of Engineers (USACE) Section 404 and Section 408 permits

OC River Walk Hydrology and Hydraulics 3-5
Section 3 – Study Area Description

Figure 3-3: Agencies Involved with Approval of OC River Walk

OC River Walk Hydrology and Hydraulics 4-1
Section 4 – Hydrology
Hydrology

4.1 Santa Ana River Flowrates
Design flowrates in the lower Santa Ana River watershed were established as part of the USACE design plan described in the GDM, Volume 7. The lower Santa Ana River reach was designed for flowrates equal to a 190-year storm event. The 190-year event represents a Prado Dam reservoir design flood that results in a spillway crest water surface elevation of 563 feet National Geodetic Vertical Datum of 1929 (NGVD 29) with 92% of the standard project flood hydrograph being routed through Prado Dam, with the release of flood flows as soon as possible within the storm event. This results in an outflow discharge of 30,000 cubic feet per second from Prado Dam, which is routed downstream and combined with tributaries to determine the design flood peak discharges at various locations along the lower Santa Ana River.

The GDM provides design flowrates in Table III -1 of Volume 3 at several locations along the Santa Ana River, as shown on Figure 4-1. The OC River Walk project location is between two locations where the GDM flowrates are specified. Design documents for the Lower Santa Ana River Channel Plan and Profile, from Station 674+20 to 704+20 in the GDM Volume 3, included in Appendix A, provided the exact USACE design flowrate at the OC River Walk project location. At the OC River Walk study area, the 190-year design discharge is 40,000 cubic feet per second with an increase to 41,000 cubic feet per second downstream of Collins Channel (USACE GDM Vol 3, 1988). The OC River Walk project is designed using the USACE 190- year event flowrate of 40,000 to 41,000 cubic feet per second.

Figure 4-1

OC River Walk Hydrology and Hydraulics 5-1
Section 5 – HEC-RAS Hydraulic Modeling
HEC-RAS Hydraulic Modeling
PACE developed a detailed hydraulic model of the study reach using the Hydraulic Engineering Center River Analysis System ( HEC-RAS), version 6.4.1. Steady and unsteady models were created to simulate various flows within the river channel . Hydraulic models were used to evaluate changes in water surface elevations and velocity, freeboard within the river, sediment transport potential, potential bridge scour, and an impoundment deflation scenario.

5.1 Summary of HEC-RAS Models
Multiple HEC-RAS models were used for the OC River Walk hydraulic analysis, summarized below:

• Santa Ana River Received USACE Model (Steady-State) – Model received from the USACE.

Geometry of the channel is simplified to a trapezoidal channel based on the as-built condition from USACE as-builts dated 1990–1994. This model represents the as-built condition of the Santa Ana River.

• Santa Ana River Existing Condition Model (Steady-State) – The received USACE model was modified by updating the cross sections with new topography while preserving the as-built channel invert. This model represents the existing condition of the Santa Ana River and provides a baseline for comparison to any proposed improvements.

• Santa Ana River Proposed Condition Model (Steady-State) – The proposed condition model represents the condition where the Santa Ana River improvements related to the OC River Walk development have been constructed. The channel side slopes and top of bank are modified to the OC River Walk design.

• Impoundment Deflation Scenario (Unsteady-State) – The impoundment deflation scenario uses the proposed condition model to analyze various inflatable impoundment deflation scenarios. The model extends downstream to include the River View Golf Course.

5.2 HEC-RAS Modeling
The USACE Santa Ana River model was obtained and used as the baseline for the existing condition model.

The model received from the USACE extends from Prado Dam to the Pacific Ocean, so it was truncated to only span the project area, from approximately 1,100 feet downstream of Orangewood Avenue to approximately 2,600 feet upstream of Ball Road . The cross sections are spaced roughly 200 feet apart except for sections located near bridges, drop structures, or other abrupt changes in channel geometry.

The USACE model elevations were originally in NGVD 29, but were converted and georeferenced to the North American Vertical Datum of 1988 ( NAVD 88) and California State Plane Coordinate System for this study.

An updated existing conditions model of the project reach was developed by revising the USACE model sections with new light detection and ranging ( LIDAR) data. The HEC-RAS workmap is shown on Figure 5-2. The new LIDAR was flown on October 25, 2022, and compiled into 1-foot contours with elevations in North American Vertical Datum of 1988 (NAVD 88). New HEC-RAS cross sections were cut using the new terrain data . Existing earthen T and L levees in the channel bottom produced varied invert elevations, section to section, resulting in an unrealistic streambed profile . The earthen T and L levees are sacrificial and expected to erode away during a storm, so the inverts of the updated HEC -RAS sections were set to the invert elevations of the original USACE sections, resulting in a realistic streambed profile (see Figure 5-1).

OC River Walk Hydrology and Hydraulics 5-2
Section 5 – HEC-RAS Hydraulic Modeling

Figure 5-1: HEC-RAS Cross Section 71772, T and L Levee Invert “Smoothing”

The Manning’s roughness values for the HEC -RAS models are consistent with the values used in the received USACE model. The Manning’s values for the left and right overbanks are consistently set to n =

0.03, while the main channel Manning’s values vary from n = 0.03 to n = 0.05.

The boundary condition was taken as a “normal depth slope” or slope -area method, which is determined from the natural downstream slope of the existing streambed . The selection of the boundary conditions in the model is not critical for t his study since the upstream and downstream limits of the model are a significant distance away from the revision reach.

All steady-state models were run with a subcritical flow regime . The subcritical flow regime produces the most conservative estimate o f water surface elevations, which is preferable to determine the impact to freeboard in the proposed condition.

The Energy and Momentum methods were used to calculate the hydraulics of each bridge with in the HEC-RAS model. The model was set to use the highest energy answer.

The drop structures were modeled as inline structures, with flow going through the structure modeled as a broad-crested weir.

5.3 Floodplain Hydraulics
The existing and proposed condition models were compared to quantify any changes to hydraulics as a result of the proposed improvements. The purpose of the existing condition model is to serve as a baseline that represents the as-is, as-built condition of the Santa Ana River. The proposed condition model includes all channel improvements and modifications.

The existing condition HEC-RAS model shows that flow depths for the design discharge [Q190 = 40,000 to 41,000 cubic feet per second ( cfs)] range from 11.2 to 17.6 feet, and channel velocity ranges from 7.6 to

11.5 feet per second (fps).

The proposed condition analysis shows that flow depths for the design discharge range from 11.2 to 17.7 feet. Channel velocity for the design event ranges from 7.6 to 11. 7 fps. Appendix E compares the flow depths and velocities from the two conditions.

OC River Walk Hydrology and Hydraulics 6-1
Section 6 – Inflatable Dams and Operations
Inflatable Dams and Operations
A key element of the OC River Walk project is the proposed water impoundments that provide nearly a year round water body for the river walk experience. Three inflatable dams will create two impoundments, which are designated as the “north” impoundment and “south” impoundment, as shown on Figure 6 -1. The impoundments provide multiple benefits, including groundwater recharge, outdoor recreation, and aesthetic improvements.

Figure 6-1: OC River Walk Impoundments

6.1 Inflatable Dams
Inflatable rubber dams have been selected to create the impoundments because they can be deflated during major river flow storm events to maintain full flood flow capacity in the Santa Ana River channel. The inflatable dam s are constructed with a reinforced rubber structure, which will be resilient enough to withstand extended exposure to ultraviolet light and scouring resulting from normal operation of the Santa Ana River during the rainy season. The rubber structure will be designed with a robust anchorin g system in order to secure it to its riverbed foundation and the sidewalls of the embankment, preventing slippage of or damage to the inflatable dam . The design and operation is similar to the inflatable dams OCWD has operated for 30 years, upstream of the project area in the Santa Ana River at the Imperial and Five Coves diversion locations.

Each dam will be equipped with an automated inflation and deflation system , including an inlet/outlet compressed air piping system, compressor, pressure relief valve, and a control and monitoring system that will be housed within a sound attenuating enclosure (precast vault or aboveground building as the preferred option).

Operational procedures of the impoundments are built on extensive analysis of the Santa Ana River hydrology and Prado Dam release procedures. The goals are effective utilization of Groundwater Replenishment System ( GWRS) supply through increased groundwater recharge , channel flood conveyance capacity, and water quality of the im poundments. Three operational conditions are defined:
dry weather operation, low river flow operation, and high river flow operation.

6.1.1 Dry Weather Operation
The Santa Ana River watershed is located in an arid region that receives little precipitation during the dry season, so there is generally no local tributary flow into the project reach of the river beyond dry weather nuisance flows. The Santa Ana River base flow comes from Prado Dam, operated by the U.S. Army Corps of Engineers (USACE), which coordinates releases with OCWD from the reservoir for OCWD groundwater recharge. It is intended that OCWD will coordinate releases of Prado Dam to ensure that, in most cases, this base flow is not sufficient to reach the project site, as it percolates either in offline basins through rubber

OC River Walk Hydrology and Hydraulics 6-2
Section 6 – Inflatable Dams and Operations
dam diversions at Imperial and Five Coves or into the riverbed upstream of OC River Walk. Thus, the Santa Ana River reach at OC River Walk will be mostly dry without the use of GWRS water from OCWD . This condition is defined as dry weather operation.

During dry weather operation, the impoundment water levels will be maintained using GWRS water supplied by OCWD. To address impoundment water quality concerns, d ry weather nuisance flows in all adjacent tributary storm drain lines will be captured /diverted by gravity . These nuisance flows will be pumped to Orange County Sanitation District sewer lines and treatment facilities, with a few storm drain lines on the east side of the project discharged to the river channel downstream of the lower impoundment . This will minimize the possibility of any dry weather flows reaching the impoundments and mixing with GWRS water.

In this operational condition, the impoundments will be filled to within 6 to 12 inches of the impoundment overflow elevation and maintained , with the ability to bypass a portion of the water through a bypass structure containing a modulating weir so water levels and discharge flow can be controlled.

To summarize, d ry weather operation is the condition where no surface flow, from any combination of tributary runoff and Prado Dam release, reaches the project site . In this condition, the impoundments are filled with only GWRS water to maximize water quality for aesthetics and potential recreational use.

6.1.2 Low River Flow Operation
A low flow event is defined as a precipitation event that produces expected flow volumes at the project site of less than 200 acre-feet (the volume of water retained by the two impoundments). Forecast monitoring of rainfall is already utilized for the operation of the Imperial and Five Coves rubber dams, as well as releases from Prado Dam, which constitutes the majority of the flow in the Lower Santa Ana River watershed. During a rain event, the dry weather nuisance diversion systems are turned off, allowing flow from the tributaries to enter the river. Flows to the project site will consist of a combination of flows from the surroundi ng tributaries and from Prado Dam releases.

Generally, in low flow conditions the GWRS water supply to the impoundments will be halted , and the GWRS water will be allowed to infiltrate or may be pumped to off -river basins operated by OCWD . Santa Ana River flows, either tributary or from Prado, will fill the impoundments up to the 200-acre-foot capacity.

In any event where flows over the rubber dam reach a 6-inch nappe (approximately 320 cfs), the inflatable dams will be deflated.

To summarize, low flow is the condition where there is flow in the channel at the project site, with the total expected volume less than 200 acre-feet and the peak flow during the event less than 320 cfs.

6.1.3 High River Flow Operation
High flow events are defined as events where the flow s reaching the project site , which include tributary runoff and flows from Prado Dam, are 200 acre-feet or greater. In these conditions, both impoundments will be evacuated and the rubber dams will be deflated to allow complete storm conveyan ce in the Santa Ana River channel.

For this operation, GWRS inflows to the impoundments will be halted and allowed to fully infiltrate, which takes approximately 10 days, or the GWRS water will be drained and pumped to Burris Basin , which is anticipated to take approximately 3 days . The impoundments will then be fully deflated to maintain peak flood capacity of the Santa Ana River channel. In the later parts of the storm, the dams will be reinflated with the intent of capturing the full operation volume, or 200 acre-feet, in both impoundments.

During any event, regardless of expected volume, when the flow exceeds 320 cfs (6 inch nappe) over the dams, they will automatically deflate as a safety mechanism to prevent damage.

OC River Walk Hydrology and Hydraulics 6-3
Section 6 – Inflatable Dams and Operations

6.1.4 Collins Channel
There is an inflatable dam located in Collins Channel where it meets the SAR. This inflatable dam prevents GWRS water from backing up into Collins Channel and prevents dry weather runoff from Collins Channel from entering the impoundments. The crest of the Collins Channel inflatable dam will be at the same elevation as the north SAR dam.

The Collins Channel dam will be operated in conjunction with the OC Riv er Walk impoundments and will be raised and lowered to facilitate various operating conditions. During dry weather, with the Collins Channel dam inflated, a pump station will pump flow in Collins Channel to the S AR downstream of the OCRW impoundments. During storm events, the Collins Channel dam will be lowered in conjunction with the OCRW dams. The operation of the Collins Channel dam will maintain the flow pattern of the Collins Channel, and will not impact existing Collins Channel drainage capacity.

6.1.5 Interior Drainage to the Impoundments
A preliminary interior drainage analysis was completed for the project area to determine the existing interior drainage paths. The analysis includes evaluating any pipes draining into the Santa Ana River within the project reach and determining whether a pipe is abandoned or not, and if and where the pipe drains into the system.

Watersheds south of Ball Road and north of the SR -57 Freeway were defined as contributing drainage within the impoundment study area . Within this area, Anaheim has fourteen (14) contributing watersheds, while the City of Orange has twelve (12). ArcGIS, a Geographic Information Systems (GIS) software, was utilized in conjunction with available survey information and as-built information to establish the watershed characteristics. The respective outfall structures of the watersheds identified that drain to the Santa Ana River within the project reach are summarized in Table 6-1 and Table 8-2, separated into the east bank and west bank, respectively.

Table 6-1: East Bank, City of Orange Interior Drainage
Watershed Name # Station
Outfall
Size
Outlet Invert
Elevation
Area
Drained
(in) (ft) (ac)
Taft Ave US1 748+15 54"Ø 166.1 94
Brian St. US2 739+93 42"Ø 162.5 14
SPRR Bridge US3 735+12 42"Ø 153 49
Promenade Main 101 725+19 54"Ø 154.5 45
Promenade Parking Lot 102 716+15 36"Ø 150.7 12
Katella (East Bank) 103 710+39 27"Ø 154.4 6
Collins Channel 201 699+34 60' (W) x
10' (H) 147.5 2992
Collins Ave. 202 695+64 48"Ø 146.5 62
OC Sheriff's Department 301 692+94 18"Ø 146.8 9
OC Children and Family
Services 302 684+02 36"Ø 144.6 10
YRC Freight 303 682+98 36"Ø 143.7 14
Orangewood Ave DS1 607+10 48"Ø 134 38

OC River Walk Hydrology and Hydraulics 6-4
Section 6 – Inflatable Dams and Operations
Table 6-2: West Bank, City of Orange Interior Drainage
Watershed Name # Station
Outfall
Size
Outlet Invert
Elevation
Area
Drained
(in) (ft) (ac)
Arena Corporate Center #1 1A1 728+89 21"Ø 159.7 10
Arena Corporate Center Main 1A2 718+66 48"Ø 154 25
Honda Center #1 1A3 714+13 36"Ø 152.1 3
Honda Center #2 1A4 710+81 27"Ø UNKNOWN 3
Honda Center Main + Katella 1A5 709+03 54"Ø 150.5 30
Artic #1 / Meadow Park 2A1 703+26 18"Ø ABANDONED 3
Artic #2 / Meadow Park 2A2 695+07 36"Ø ABANDONED 5
Artic #3 3A1 689+94 42"Ø 149.6 3
Artic #4 3A2 687+65 18"Ø 145.3 1
Artic Main + SR-57 3A3 687+18 48"Ø 143.5 65
Angel Stadium 3A4 683+61 18"Ø UNKNOWN 6

At outfalls where the water surface elevation of the impoundment is greater than the invert of the storm drain, a cast iron flap gate or an elastomer duckbill check valve will be installed. This will prevent the flow of GWRS water into the storm drain and diversion system.

6.2 Hydraulic Analysis for Rapid Drop of Rubber Dam Impoundments The inflatable dams will be managed to account for projected storm events that will cause large flows through OC River Walk . Any necessary evacuation of the impoundments is ex pected to occur through infiltration within 10 days; however, the hydraulics of a sudden deflation and resultant release of impounded water were investigated.

Approximately 9,500 feet downstream of the south impoundment is the Riverview Golf Course. This 18-hole golf course is located within the Santa Ana River floodplain, with the Santa Ana River running directly through the fairway. Potential impacts to the Riverview Golf Course and downstream areas were analyzed considering an emergency deflation of the dams holding full impoundment volumes. The analysis involved the following tasks, which will be discussed in detail in the following sections:

• Development of a design hydrograph for use in the hydraulic analysis • Development of a HEC-RAS model of the study reach to characterize hydraulics • Analysis of results and determination of downstream impacts

6.2.1 Hydrology
In order to model impacts to the golf course, a hydrograph of the inflatable dam deflation scenario was developed using the anticipated deflation time along with a stage -volume relationship. Three scenarios were analyzed resulting in three inflow hydrographs, described below:

• North Impoundment Deflation – Scenario where only the filled north impoundment is deflated.

• South Impoundment Deflation – Scenario where only the filled south impoundment is deflated.

• Simultaneous North and South Impoundment Deflation – Scenario where both the north and south impoundments are deflated concurrently.

Each deflation scenario was modeled using weir discharge equations . The scenarios assume that the deflation of the rubber dam will behave in the following manner . First, the behavior of the rubber dam will

OC River Walk Hydrology and Hydraulics 6-5
Section 6 – Inflatable Dams and Operations
act as a rect angular weir from 𝑡0 (𝑡𝑖𝑚𝑒 = 0) to 𝑡 =
1 4 𝑑𝑒𝑓𝑙𝑎𝑡𝑖𝑜𝑛 𝑡𝑖𝑚𝑒 . During this stage , the discharge is calculated by the rectangular weir equation:

𝑄 = 𝐶𝐿𝐻
3 2

Where:

Q = discharge (cfs)
C = weir constant, assume 3
L = weir length (ft)
H = head above horizontal crest (ft)

Deflation will then transition to act as a rectangular weir with a v -notch, or a combination weir. This assumption is used from 𝑡 =
1 4 𝑑𝑒𝑓𝑙𝑎𝑡𝑖𝑜𝑛 𝑡𝑖𝑚𝑒 to the end of deflation . During this stage, a combination of the rectangular weir discharge and v-notch weir discharge equations are used:

𝑄 = 𝐶𝐿𝐻
3 2 + 3.9 ℎ1.72 − 1.5

Where:

Q = discharge (cfs)
C = weir constant, assume 3
L = weir length (ft)
H = head above horizontal crest (ft)
h = head above horizontal crest (ft)

6.2.2 Summary of Results
The resultant hydrographs for each of the three scenarios are shown in Figure 6-2. The north impoundment deflation will result in a peak discharge of 2,833 cfs, the south impoundment deflation will result in a peak discharge of 2,071 cfs, and the combined north/south simultaneous deflation scenario will result in a peak discharge of 4,850 cfs.

North Deflation Hydrograph
(Qpeak = 2,833 cfs)
South Deflation Hydrograph
(Qpeak = 2,071 cfs)
Simultaneous Deflation
Hydrograph (Qpeak = 4,850 cfs)

Figure 6-2: Deflation Hydrographs

0 1000
2000
3000
4000
5000
0 20 40
Outflow (cfs)
Time (minutes)
0 1000
2000
3000
4000
5000
0 20 40
Outflow (cfs)
Time (minutes)
0 1000
2000
3000
4000
5000
0 20 40
Outflow (cfs)
Time (minutes)

OC River Walk Hydrology and Hydraulics 6-6
Section 6 – Inflatable Dams and Operations

6.3 Hydraulic Modeling
An unsteady one -dimensional HEC-RAS model of the Santa Ana River was created to analyze the dam deflation scenarios.

6.3.1 Modeling Parameters
The USACE has an existing model of the Santa Ana River that extends from Prado Dam to the Pacific Ocean that was used as a basis of the analysis. The model was truncated to span the study area, with the downstream cross section as RS 53380, at the downstream of the Riverview Golf Course, and the upstream cross section as RS 69601, approximately 240 feet upstream of the OCTA/SCRRA railroad bridge.

The cross sections are spaced roughly 200 feet apart except for sections located near bridges, drop structures, or other abrupt changes in chan nel geometry. The USACE model elevations were originally in NGVD 29, but were converted and geo -referenced to NAVD 88 and California State Plane Coordinate System for this study.

6.3.1.1 Analysis Inflow
The inflow hydrographs were created through the analysis desc ribed in Section 6.1. To obtain a stable model, each hydrograph was modeled with a minimum flow of 500 cfs.

6.3.1.2 Downstream Boundary Condition
The model features a normal depth boundary condition at the downstream end of the model, with a friction slope of 0.001 ft/ft. This normal depth boundary condition is more appropriate for an unsteady model with varying flow rates than the original known water surface elevation boundary condition.

6.3.1.3 Unsteady Flow Simulation Parameters
The unsteady flow simulation was run for 1 hour and 35 minutes with a 1-second computation interval.

6.3.2 HEC-RAS Results
The unsteady flow results show that the golf course will not be negatively impacted by rapid dam deflation within the OC River Walk development. The results of the simultaneous di scharge of the north and south impoundment areas show a peak flow of approximately 4,850 cfs . The max imum profile from the simultaneous discharge was compared to a steady-state 2-year storm event.

The discharge frequency flow events for the OC River Walk project reach are available in the Santa Ana River Design Memorandum Phase II GDM on the Santa Ana River Mainstem, Volume 7 , in Table 7 -10 (USACE, 1988). The GDM shows that the 2-year storm event peak discharge is 4,700 cfs.

The results show that the maximum profile has lower water surface elevations than the 2-year steady-state event. This indicates that the dam deflation scenario has smaller impacts than a 2 -year storm event. The Riverview Golf Course will not be impacted by the worst-case dam deflation scenario associated with the OC River Walk development. Each of the three dam deflation scenarios analyzed shows impacts less than those of a 2-year storm event.

OC River Walk Hydrology and Hydraulics 7-1
Section 7 – Pedestrian Bridge Scour Analysis
Pedestrian Bridge Scour Analysis
This section summarizes the preliminary scour analysis completed for the proposed pedestrian bridge upstream of Katella Avenue.

7.1 Total Scour Analysis
Using the 190-year design flow rate, the total anticipated scour at the proposed bridge is determined by analyzing channel adjustments possible from long-term degradation, general scour, bend scour, contraction scour, local scour, low-flow incisement, and bed form scour.

𝑍𝑇𝑜𝑡𝑎𝑙 = 𝑍𝐿𝑜𝑛𝑔−𝑇𝑒𝑟𝑚 + 𝑍𝐺𝑒𝑟𝑛𝑒𝑟𝑎𝑙 + 𝑍𝐵𝑒𝑛𝑑 + 𝑍𝐵𝑒𝑑 𝑓𝑜𝑟𝑚 + 𝑍𝐿𝑜𝑤 𝑓𝑙𝑜𝑤 𝑖𝑛𝑐𝑖𝑠𝑒𝑚𝑒𝑛𝑡 + 𝑍𝐿𝑜𝑐𝑎𝑙 𝑆𝑐𝑜𝑢𝑟 (𝐶𝑜𝑛𝑡𝑟𝑎𝑐𝑡𝑖𝑜𝑛,𝑃𝑖𝑒𝑟,𝑎𝑛𝑑 𝐴𝑏𝑢𝑡𝑚𝑒𝑛𝑡)

7.1.1 Long-Term Scour
Long-term scour adjustments aim to estimate scour from fluvial processes that occur over several years. In the case of the Santa Ana River, there are a series of grade control structures periodically spaced along the riprap-lined trapezoidal channel. These grade control structures will control the fluvial processes in the river and keep the channel from eroding past the top of each structure. Therefore, the long-term erosion of the study area is controlled by the downstream grade control structure. To conservatively calculate the long-term adjustment, it is assumed that the reach will erode to the top elevation of the downstream grade control, essentially causing a zero slope projected from the top of the grade control to the next upstream hydraulic structure. At the location of the bri dge, the long -term scour, calculated by subtracting the top elevation of the grade control from the existing invert elevation, was found to be 2.4 feet.

7.1.2 General Scour
General scour is the lowering of the stream bed over a relatively short time period such as a single flow event. In order to estimate general scour, a series of equations were used. HEC-RAS includes a series of hydraulic design calculators , including a riprap calculator and a s cour calculator. The scour calculator includes various widely used empirical local scour equations to provide a range of scour depth s expected at a cross section . Both the upstream and downstream cross sections were analyzed using this tool.

General scour was also found using the L os Angeles County Flood Control District (LACFCD) Hydraulic Design Manual, Table F-31, which estimates cutoff depth based on velocity. The equations analyzed and the resultant general scour are summarized below. The D50 used in the general scour calculations was

1.396 millimeters ( mm) as specifie d in the grain size analysis for the Orangewood Avenue Bridge Improvement project, which was taken from the riverbed at Orangewood Avenue, downstream of the proposed pedestrian bridge.

The final general scour value was chosen as 6.4 feet, specified from t he Neil method. This value was selected as a median, conservative, empirical estimate of general scour at the proposed pedestrian bridge.

7.1.3 Bend Scour
Bend scour occurs on the outside of a river bend and is largely based on the “radius of curvature” for the bend. The reach in the vicinity of the proposed pedestrian bridge is very straight, so bend scour is not expected to occur within the study area.

7.1.4 Bedform Scour
Bedform scour can develop in sand beds as a result of the interaction between hydraulic curves and the bed sediment. Bed forms include dunes, antidunes, bars , and ripples within the main channel. The LA County Sedimentation Manual uses a nomograph to relate channel velocity to a bed form height. Using the HEC-RAS velocity for the bridge cross sections, a bed form height of 1 foot is anticipated based on the LA County method.

Table 7-1: General Scour Calculation Method Summary

Method Equation
General Scour Result (ft)
U/S Cross
Section
D/S Cross
Section
Neil ∆𝑦 = 𝑍 ∙ 𝐷𝑏𝑓̅̅̅̅̅ (
𝑄𝑑
𝑊⁄
𝑄𝑏𝑓
𝑊𝑏𝑓
⁄
)
𝑚

∆𝑦 = scour depth
𝑍 = 0.5 for straight reaches
𝑚 = 0.67 for sandy reaches
𝐷𝑏𝑓̅̅̅̅̅ = average bankfull cross section depth,
approximated with hydraulic depth
𝑄𝑑 = design flow
𝑄𝑏𝑓= bankfull flow
𝑊 = flow width of design event
𝑊𝑏𝑓 = bankfull flow width

6.4’ 6.3’
Lacey ∆𝑦 = 𝑍 ∙ 0.47 ( 𝑄𝑑

1.76√𝑑𝑚
)
1 3

∆𝑦 = scour depth
𝑍 = 0.25 for straight reaches
𝑄𝑑 = design flow
𝑑𝑚= median grain size

3.1’ 3’
USBR
Mean
Velocity
∆𝑦 = 𝑍 𝐷̅
∆𝑦 = scour depth
𝑍 = 0.25 for straight reaches
𝐷̅= Depth
3’ 3’
Blench ∆𝑦 = 𝑍 ∙
(𝑄𝑑
𝑊⁄ )
2 3
(𝐹𝐵0)
1 3

∆𝑦 = scour depth
𝑍 = 0.6 for straight reaches
𝑄𝑑 = design flow
𝑊 = flow width of design event
𝐹𝐵0 = Blench’s Zero Bed Factor

10.9’ 10.9’
USBR
∆𝑦 = 2.47 +

0.937 (𝑄𝑑
𝑊⁄ )

3.45 , 𝑖𝑓 (𝑄𝑑
𝑊⁄ ) < 3.45
and
∆𝑦 = 𝐾 (𝑄𝑑
𝑊⁄ )

0.24 , 𝑖𝑓 (𝑄𝑑
𝑊⁄ ) ≥ 3.45
∆𝑦 = scour depth
𝐾 = 2.45
𝑄𝑑 = design flow
𝑊 = flow width of design event

7.6’ 7.6’
LA County
Cut of
Depth
NA 8’ 8’
Note:

1. Values italicized in red indicate that the D50 is not within the range anticipated to use the equation, and therefore should not be considered for general scour.

OC River Walk Hydrology and Hydraulics 7-3
Section 7 – Pedestrian Bridge Scour Analysis

7.1.5 Low-Flow Incisement
The low-flow channel incisement generally represents a small channel formed by smaller 5 - to 10-year return storms. The incisement is form ed as these low flows seek the most hydraulically efficient path downstream. The LA County Sedimentation manual specifies the use of 2 feet for a conservative estimate of low-flow incisement.

7.1.6 Local Pier Scour
Local scour occurs as the result of the proposed pedestrian bridge . The impacts of the local scour components are generally limited to the vicinity of the bridge that causes them; however, they are significant because they are frequently many times larger than the long -term or general adjustment components of scour. Local scour components are contraction scour, pier scour , and abutment s cour. All three are calculated in HEC -RAS, following the procedures outlined in HEC -18: Evaluating Scour at Bridges , 5th Edition (FHWA, 2012).

According to the hydraulic output of the HEC-RAS modeling, contraction scour is computed based on the live-bed equation and pier scour based on the CSU equation . The proposed pedestrian bridge shows 3.7 feet of contraction scour and 4 feet of pier scour. This results in 7.7 feet of local scour.

7.2 Summary of Total Scour
The total scour anticipated at the proposed pedestrian bridge is the sum of all individual scour components analyzed. Each scour component analyzed and the total scour for the proposed pedestrian bridge is summarized below.

Table 7-2: Summary of Each Scour Component

Scour Component Expected Adjustment (ft)
Long-Term 2.4
General 6.5
Bend 0
Bedform 1
Low Flow Incisement 2
Local Scour 7.7
Total Scour 19.6

OC River Walk Hydrology and Hydraulics 8-1
Section 8 – OC River Walk Development Impact Analysis
OC River Walk Development Impact Analysis

8.1 Hydraulic Impacts
Hydraulic impacts encompass changes to depth, velocity, freeboard, and scour within the Santa Ana River as a result of the proposed OC River Walk development.

8.1.1 Depth and Velocity
Depths within the Santa Ana River were analyzed through the existing and proposed HEC-RAS modeling.

The change in depth as a result of the proposed project shows a maximum increase of 0.5 f eet, and in some areas a decrease in depth up to 0.2 f eet. The changes to depth are general ly upstream of the two proposed pedestrian bridges. These changes in depth are minimal; see Figure 8-1.

Similarly to depth data, velocity data was analyzed by comparing the existing and proposed HEC -RAS model results. The changes to velocity as a result of the proposed project include increases up to 0.6 fps and decreases up to 0.9 fps. The decreases are generally located around the proposed pedestrian bridges, where the addition of piers within the main channel slows down the flow, decreasing velocity. The maximum increase in velocity is localized to the pro posed Meadow Park, which includes a small change in the bank alignment that slightly decreases flow area, therefore increasing velocity. Changes in velocity between the existing and proposed conditions are plotted in Figure 8-2.

8.1.2 Freeboard
The Santa Ana River is designated as a levee , which has minimum freeboard requirements. Freeboard is the vertical distance between the design water level and the top of bank. The USACE GDM Volume 3 specifies the minimum freeboard in the project reach as 2.5 feet. Freeboard was calculated for the existing and proposed condition HEC -RAS models by subtracting the design water surface elevation from the top of bank. A comparison of the freeboard provided in the existing and proposed condition models is detailed in Appendix E.

The freeboard analysis shows there is generally sufficient freeboard ( greater than 2.5 feet) in the existing condition, with some deficiencies located just upstream of the SR 57 bridge, LOSSAN railroad bridge, and Katella Avenue bridge and around the crest of the downstream drop structure. In the proposed condition, the amount of freeboard gained or lost is directly related to the change in water surface elevation. The proposed project aims to fix any deficiencies in freeboard in the existing condition by raising the top of bank to meet the freeboard requirement specified in the USACE GDM. Freeboard will improve as a result of the proposed project.

8.1.3 Scour
The as-built/existing toe elevations range from a minimum of 5 feet along the channel up to 10 -15 feet at drop structures and stabilization structures. A preliminary cutoff depth analysis was completed using the LACFCD Hydraulic Design Manual Table F -31, Levee Criteria, Cut -Off Depths. As discussed in Sections

5.3 and 8.1.1, changes in velocity are minimal, which mean s changes in scour depth are also minimal.

There are no anticipated changes to scour depth as a result of the proposed channel improvements.

8.2 Hydrologic Impacts
Hydrologic changes are related to the ground cover within the project site. The proposed project will change 26,400 linear feet of grouted/un-grouted riprap to soil cement and riprap. This may result in a small increase to impervious area within the project site. However, in the perspective of the lower Santa Ana River watershed, this is a negligible increase. The lower Santa Ana River watershed covers a n approximately 200 square mile area, while the change in pervious area is less than 0.01 square mile. There would be no significant impacts to the Santa Ana River hydrology as a result of the proposed bank modifications.

OC River Walk Hydrology and Hydraulics 8-4
Section 8 – OC River Walk Development Impact Analysis

8.3 Water Quality Changes
Surface drainage in the project site will primarily remain the same, with the river trails and surrounding areas draining to the Santa Ana River. A Water Quality Management Plan (WQMP) will be developed which will address the required water quality components for the project elements. Best Management Practices (BMP’s ) will be implemented as required following the Santa Ana Region Technical Guidance Document (TGD). GWRS water from OCWD will be dechlorinated prior to being discharged into the Santa Ana River.

Further chemical addition prior to discharge is anticipated for concrete corrosion control (e.g. calcium chloride addition) and algae control (e.g. alum addition).

8.4 Human Contact Changes and Impacts
One of the largest changes to the Santa Ana River as a result of the OC River Walk project is human access to the river and surrounding project site. The existing condition of the project site primarily only allows for access through the SART bike path. This unsupervised travel path allows for nuisance use of the dirt areas adjacent to the river, promoting poor trash management and creating the potential for bacterial and biological pollution. In addition, there are no trash receptacles or public restrooms in the vici nity of the SART.

During operation of the proposed impoundments, there are opportunities to divert trash from the Santa Ana River. During dry weather operation, trash from the storm drain diversions will be captured and no longer enter the Santa Ana River. In the event of l arge storms, the Santa Ana River will operate as it currently does, any trash and debris within the river will continue downstream.

In the proposed condition, there will be an anticipated increase in human access to the Santa Ana River , including recreat ion within the river . This increased access and site development will include the construction of public sanitary facilities and trash receptacles. The presence of these facilities will divert trash and other pollutants away from the Santa Ana River and into proper disposal pathways using source control. In addition, the C ity will maintain the project area and proposed impoundments, removing any accumulations of debris. It is anticipated there will be a decrease in pollutant loading through the construction of the proposed development and related facilities.

Any recreational elements as part of OC River Walk will generally operate between 5:30am and 10:30pm, which aligns with the City of Anaheim’s standard operating schedule. The City of Orange’s standard park operating hours are from 5:00am to 11:00pm.

OC River Walk Hydrology and Hydraulics 9-1
Section 9 – Conclusion
Conclusion
The OC River Walk project , located within the Santa Ana River corridor between the Ball Road and Orangewood Avenue bridge crossings, will transform the Santa Ana River by removing the existing riprap bank lining and replacing it with soil cement stepped terraces, extending the exis ting SART bike path, adding two additional pedestrian bridges across the Santa Ana River, and creating two river impoundments that allow for infiltration.

HEC-RAS modeling of the project site was completed using hydrology from the USACE Design Memorandum for Phase II GDM on the Santa Ana River Mainstem , Volume 3, for the lower Santa Ana River. The final design flow rate represents a 190-year storm with a flow rate of 40,000 to 41,000 cfs within the project reach . Hydraulic modeling of the project reach inc luded floodplain hydraulics, freeboard , and scour. Comparison between the existing and proposed conditions showed minimal changes in depth, velocity, freeboard, and scour.

The proposed project will also change the way that users can interface with the San ta Ana River . The development improves human impacts on the Santa Ana River by decreasing pollutant loading through the inclusion of sanitary facilities and trash receptacles in the proposed design. In addition, management of the two impoundments will incl ude maintenance activities that divert trash from washing downstream to the Pacific Ocean.

Operation of the dam impoundments will have minimal impacts on downstream flood control facilities and users. Modeling of three deflation scenarios showed that the hydraulic impacts would be the same as those from a 2-year return storm. Minimal flow depth and velocity changes would occur.

OC River Walk Hydrology and Hydraulics R-1
References
References

Federal Highway Administration (FHWA), Hydraulic Engineering Circular Number 18. April 2012.

Orange County Water District, Orange County Water District Application to Appropriate Santa Ana River Water. March 2006.

U.S. Army Corps of Engineers, and Federal Emergency Management Agency (FEMA). National Levee Database, USACE, June 2017, levees.sec.usace.army.mil/map-viewer/index.html.

U.S. Army Corps of Engineers, Santa Ana River Design Memorandum No . 1, Phase II GDM on the Santa Ana River Mainstem including Santiago Creek. Volume 3, Lower Santa Ana River. August 1988.

U.S. Army Corps of Engineers, Santa Ana River Design Memorandum No . 1, Phase II GDM on the Santa Ana River Mainstem including Santiago Creek. Volume 7, Hydrology. August 1988.

Appendix A

Appendix A – ACOE GDM Hydrology Documentation

Appendix A
Pages from USACE Design Memorandum No. 1 Phase II GDM on the Santa Ana River Mainstem, Volume 3 Lower Santa Ana River ucFILEUS Army Corps
of Engineers
Los Angeles District SANTA ANA RIVER BASIN, CALIFORNIA
AD-A204 544
.Sa ta Ana River
Design Memorandum No. 1
PHASE 1 GDM ON THE

SANTA ANA RIVER MAINSTEM
including Santiago Creek
• , ,,... .. .... E L E C T F- 00
VOLUME 3

LOWER SANTA ANA RIVER
(PRADO DAM TO PACIFIC OCEAN)
89 2 2 005August 1988

Ninates Design Flood Peak Discharges
3-03 Table III-1 lists the design flood peak discharges (based on future conditions) at several locations along the Lower Santa Ana River as shown in figure 7. The design flood peak discharges on the Santa Ana River below Prado Dam are produced by a general storm critically centered above Prado Dam with contemporaneous rainfall from the same general storm falling on the drainage area bilow Prado Dam. This storm resulted in a outflow discharge of 30,000 ft /sec from Prado Dam, which was routed downstream and combined with the contemporaneous flow of downstream subareas to determine the design flood peak discharges at each location. A storm centered below Prado Dam, whether a local storm or a general storm, will not be more critical than the selected storm centered upstream from Prado Dam.

Table III-1. Design Flood Peak Discharges Along
the Lower Santa Ana River.

Design
Location Station Discharge (cfs)*
Prado Dam Outflow 1607+50 30,000
Downstream from:

Wardlow Canyon 1603+10 31,000
Weir Canyon Road 1207+30 37,000
Imperial Highway 1065+61 38,000
Carbon Canyon Diversion Channel 846+25 40,000
Santa Ana Freeway 625+39 42,000
Santiago Creek 564+00 46,000
Hamilton Avenue 72+90 47,000
Pacific Ocean 16+95 47,000
*Based on general storm upstream from Prado Dam. Design discharges below Prado Dam are approximately a 190-year event.

Interior Flood Control
3-04 Interior flood control refers to drainage from areas protected from direct river flooding by levees or floodwalls. From the end of the canyon reach at Weir Canyon Road to 17th Street in Santa Ana, the project channel levee heights are generally 2-4 feet above the natural ground line. From 17th Street to the Pacific Ocean, the levee heights increase to about 10-15 feet above the natural ground line. Peak discharges and runoff volumes were determined for all interior drainage areas for the following three conditions: )
111-2
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*4 -. 7
it .. ' .- -- - - - --- --
- DATUM IS NATIONAL. SEODETIC VERTICAL DATUM 0F192
PL4HYDRAULIC ELEMENTS O11800
~*OO0.0000?40.00 7? IIO ~LOWER SANTA AMA RIvIN CHANNEL
_________________________STA ?04 00TO $111 704 00
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i~~~i~~~II~~~iNE ACCESSS 40D0 A.D DIKE T0RAIL1.3PAN ADPRFL 706+ 7I1~ 0.06* 4000 6.4 Iii 10.)12.9 10.
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40 7. 11. I~
SCALE FF44' F .0ET 40 .? 0 7 11. 2
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VALUE ENGINEERIb
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so "0+7 IN020 000
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OR AM4 vA-.PT AND VELOCIT

SAFETY PA'

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1150
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NOTE
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I is FACING STONE WIG" FILTERI1.
~ ~ - RO2 SEE SHIEET 9 FOR TYPICAL ACCESS ROAD
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DATU t NATIONAL OftETIC METICaL DA0 0oF IS
TI
JLIC EL SCALE FEE m AMYISIONS
ca of 94094
HYM'DRAULIC ELEMENTS SANT AN NfttMSCAUJIWM
)00 6.SA OBA2 e A-o3
100asf ( M C. 4.O.V.f LOWER SANTA ANA RIVER CHANNEL
00 g UD 4 .OOU 44000 U IS 104 I.? 0.0PLAN AND PROFI
00 8.8 Z 441.000.*om.'.41to.*U0I.? 10.0 6Ot STA.674+20 TO STA.70~4+20Poo 6.1. 00 4 1.

AF WITHI A,

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* SAFETY PAYS /

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2AET 0'of

Appendix A
Pages from USACE Design Memorandum No. 1 Phase II GDM on the Santa Ana River Mainstem, Volume 7 Hydrology
*IICFILLCA~j082
US ArmyCorpof Engners
Los Angel4es District SANTA ANA RIVER BASIN, CALIFORNIA AD-A204 547
Santa Ana River
Design Memorandum No. 1
PHASE 11 GDM ON THE

SANTA ANA RIVER MAINSTEM
including Santiago Creek
DTIC
E -r - 1
VOLUME 7 FEBO0?

HYDROLOGY
W?~ BU IO STA TE rN A-
Appwoeed f' i~'c
t.~A*~ August 1988 8 9 2 6 1077 01 1

Table 7-10. Santa Ana River Mainstem Discharge-Frequency Values. (Future Conditions)
Frequency of Peak Discharge
Location 200-YR 100-YR 50-YR 21-YR 10-YR 5-YR 2-YR
(in ft /s)
at Seven Oaks Dam (D.A. = 177 mi2 )
Inflow
w/o project 88,000 58,000 34,000 20,500 8,800 4,300 1,100 and w/project
Outflow
w/o project same as inflow
w/project 6,900 5,500 4,200 3,150 2,150 2,000 500
D/S of Mill Creek (D.A. = 242 mi2)
w/o project 120,000 76,000 45,000 26,000 11,700 5,600 1,400 w/project 37,000 25,000 15,500 9,300 4,300 2,050 760
D/S of City Creek (D.A. = 290 mi12 )
w/o project 125,000 80,000 48,000 28,000 12,500 5,800 1,400 w/project 50,000 33,000 21,000 13,000 5,600 2,600 800
at E Street (D.A. = 500 mi2 )
w/o project 170,000 111,000 64,000 36,000 14,500 6,300 1,450 w/project 110,000 70,000 42,000 24,000 9,400 4,000 920
at Riverside Narrows (D.A. = 824 mi2 )
w/o project 280,000 190,000 115,000 62,000 26,000 11,000 2,200 w/project 220,000 140,000 82,000 47,000 19,000 8,100 1,680 at Prado Dam (D.A. = 2255 m12 )
Inflow
w/o project 380,000 270,000 155,000 85,000 34,000 14,000 3,400 w/project 320,000 230,000 135,000 75,000 30,000 13,000 3,100 Outflow
w/o project 240,000 115,000 21,000 6,900 6,400 4,700 2,,00 w/project 30,000 30,000 30,000 22,000 11,000 6,000 3,'00 at Imperial Hwy (D.A. = 2306 mi2 )
w/o project 240,000 110,000 22,000 7,000 6,500 4,800 2,500 w/project 40,000 36,000 34,000 25,000 13,000 7,200 3,800 at Santa Ana (D.A. = 2447 m12)
w/o project 220,000 90,000 30,00) 20,400 13,000 8,400 4,700 w/project 50,000 42,000 37,000 27,500 18,000 11,000 4,700 Note: D.A. = drainage area.

Appendix B

Appendix B – Existing Condition HEC-RAS Output

HEC-RAS Plan: Existing_Topo_ACOE_Extend River: Santa Ana River Reach: Below Prado Profile: 190yr ACOE Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 77600 190yr ACOE 40000.00 172.94 184.18 180.49 185.74 0.001799 10.01 3996.02 379.15 0.54 Below Prado 77433* 190yr ACOE 40000.00 172.57 183.85 180.18 185.43 0.001819 10.08 3966.48 375.21 0.55 Below Prado 77266* 190yr ACOE 40000.00 172.21 183.51 179.87 185.12 0.001854 10.19 3927.23 371.21 0.55 Below Prado 77100 190yr ACOE 40000.00 171.84 183.16 179.57 184.80 0.001889 10.29 3888.74 367.16 0.56 Below Prado 76933* 190yr ACOE 40000.00 171.51 182.85 179.24 184.48 0.001871 10.24 3905.58 368.61 0.55 Below Prado 76766* 190yr ACOE 40000.00 171.17 182.56 178.89 184.17 0.001842 10.18 3930.32 370.24 0.55 Below Prado 76600 190yr ACOE 40000.00 170.84 182.27 178.54 183.86 0.001817 10.12 3953.16 371.94 0.55 Below Prado 76433* 190yr ACOE 40000.00 170.37 181.93 178.18 183.55 0.001839 10.21 3917.16 366.66 0.55 Below Prado 76266* 190yr ACOE 40000.00 169.91 181.57 177.84 183.24 0.001877 10.34 3867.89 360.45 0.56 Below Prado 76100 190yr ACOE 40000.00 169.44 181.21 177.50 182.92 0.001877 10.47 3818.71 348.69 0.56 Below Prado 75900* 190yr ACOE 40000.00 169.14 180.85 177.12 182.53 0.001944 10.40 3845.79 364.66 0.56 Below Prado 75700* 190yr ACOE 40000.00 168.84 180.48 176.76 182.13 0.001922 10.32 3875.37 368.69 0.56 Below Prado 75500* 190yr ACOE 40000.00 168.54 180.11 176.39 181.74 0.001899 10.24 3906.29 372.80 0.56 Below Prado 75300* 190yr ACOE 40000.00 168.24 179.75 176.03 181.36 0.001875 10.15 3939.09 377.23 0.55 Below Prado 75100 190yr ACOE 40000.00 167.94 179.40 175.67 180.98 0.001846 10.06 3974.73 381.51 0.55 Below Prado 74969 190yr ACOE 40000.00 167.24 179.27 175.08 180.72 0.001564 9.65 4144.72 366.63 0.51 Below Prado 74927 Bridge
Below Prado 74886 190yr ACOE 40000.00 167.24 178.87 175.12 180.40 0.001775 9.92 4034.17 382.80 0.54 Below Prado 74862* 190yr ACOE 40000.00 167.19 178.78 175.12 180.35 0.001872 10.06 3976.11 382.99 0.55 Below Prado 74839* 190yr ACOE 40000.00 167.13 178.72 175.04 180.31 0.001882 10.10 3959.03 380.63 0.55 Below Prado 74815* 190yr ACOE 40000.00 167.08 178.73 174.71 180.24 0.001719 9.85 4060.91 377.07 0.53 Below Prado 74792* 190yr ACOE 40000.00 167.03 178.66 174.74 180.20 0.001768 9.95 4022.05 380.21 0.54 Below Prado 74768 190yr ACOE 40000.00 166.97 178.66 174.58 180.14 0.001619 9.77 4094.53 371.30 0.52 Below Prado 74745* 190yr ACOE 40000.00 166.92 178.65 174.49 180.09 0.001565 9.63 4151.98 375.07 0.51 Below Prado 74721* 190yr ACOE 40000.00 166.87 178.63 174.43 180.05 0.001549 9.58 4176.25 378.08 0.51 Below Prado 74697 190yr ACOE 40000.00 166.81 178.57 174.43 180.01 0.001576 9.63 4152.60 377.82 0.51 Below Prado 74674* 190yr ACOE 40000.00 166.76 178.48 174.51 179.97 0.001658 9.80 4081.43 375.74 0.52 Below Prado 74650* 190yr ACOE 40000.00 166.71 178.39 174.57 179.92 0.001740 9.95 4020.96 375.40 0.54 Below Prado 74627* 190yr ACOE 40000.00 166.65 178.30 174.46 179.88 0.001816 10.08 3969.80 375.50 0.55 Below Prado 74603 190yr ACOE 40000.00 166.60 178.24 174.42 179.84 0.001777 10.16 3938.68 361.70 0.54 Below Prado 74580* 190yr ACOE 40000.00 166.55 178.20 174.36 179.79 0.001763 10.12 3951.66 362.67 0.54 Below Prado 74556 190yr ACOE 40000.00 166.49 178.21 174.19 179.73 0.001667 9.91 4038.10 366.70 0.53 Below Prado 74552* 190yr ACOE 40000.00 166.48 178.20 174.18 179.72 0.001659 9.88 4047.94 367.80 0.53 Below Prado 74547 190yr ACOE 40000.00 166.47 178.20 174.17 179.71 0.001660 9.87 4051.10 368.70 0.53 Below Prado 74542 190yr ACOE 40000.00 166.46 178.21 174.12 179.69 0.001622 9.77 4093.05 371.97 0.52 Below Prado 74537 190yr ACOE 40000.00 166.45 178.22 174.06 179.67 0.001578 9.66 4142.27 375.46 0.51 Below Prado 74533 190yr ACOE 40000.00 166.44 178.21 174.06 179.66 0.001584 9.67 4136.34 375.07 0.51 Below Prado 74524 Inl Struct
Below Prado 74515 190yr ACOE 40000.00 154.19 169.81 162.21 170.74 0.002077 7.77 5147.15 359.31 0.36 Below Prado 74510 190yr ACOE 40000.00 154.19 169.80 162.23 170.73 0.002056 7.73 5177.65 362.85 0.36 Below Prado 74505 190yr ACOE 40000.00 154.19 169.81 162.20 170.72 0.002019 7.66 5224.65 366.25 0.36 Below Prado 74500 190yr ACOE 40000.00 154.19 169.80 162.18 170.70 0.001985 7.60 5260.44 369.40 0.36 Below Prado 74496 190yr ACOE 40000.00 154.19 169.80 162.17 170.69 0.001959 7.58 5280.13 370.33 0.35 Below Prado 74491 190yr ACOE 40000.00 154.19 169.79 162.15 170.68 0.001949 7.58 5274.76 369.87 0.35 Below Prado 74486 190yr ACOE 40000.00 154.19 169.78 162.15 170.67 0.001945 7.59 5269.57 369.36 0.35 Below Prado 74481 190yr ACOE 40000.00 154.19 169.77 162.12 170.66 0.001933 7.59 5271.07 368.89 0.35 Below Prado 74477 190yr ACOE 40000.00 154.19 169.75 162.13 170.65 0.001942 7.60 5260.35 368.64 0.35 Below Prado 74469 190yr ACOE 40000.00 157.29 169.02 165.06 170.56 0.004727 9.98 4009.46 365.19 0.53 Below Prado 74313* 190yr ACOE 40000.00 156.94 168.51 164.77 170.13 0.001814 10.21 3917.68 363.00 0.55 Below Prado 74157* 190yr ACOE 40000.00 156.59 168.22 164.42 169.84 0.001796 10.22 3914.79 359.02 0.55 Below Prado 74001 190yr ACOE 40000.00 156.24 167.96 164.10 169.56 0.001764 10.16 3935.64 359.18 0.54 Below Prado 73801* 190yr ACOE 40000.00 155.79 167.65 163.62 169.20 0.001684 10.01 3996.34 359.97 0.53 Below Prado 73601 190yr ACOE 40000.00 155.34 167.39 163.11 168.85 0.001550 9.71 4121.57 365.40 0.51 Below Prado 73467* 190yr ACOE 40000.00 155.19 167.08 163.18 168.63 0.001717 9.98 4007.02 368.08 0.53 Below Prado 73334 190yr ACOE 40000.00 155.04 166.86 162.99 168.39 0.001771 9.91 4036.46 381.00 0.54 Below Prado 73324 Bridge
Below Prado 73314 190yr ACOE 40000.00 155.04 166.38 162.93 168.06 0.001947 10.37 3856.24 364.27 0.56 Below Prado 73207* 190yr ACOE 40000.00 154.69 166.12 162.73 167.84 0.001999 10.51 3805.30 359.83 0.57 Below Prado 73101 190yr ACOE 40000.00 154.34 166.05 162.23 167.59 0.001736 9.95 4018.35 374.35 0.54 Below Prado 72934* 190yr ACOE 40000.00 153.97 165.72 161.79 167.30 0.001727 10.07 3971.56 361.60 0.54 Below Prado 72767 190yr ACOE 40000.00 153.61 165.46 161.44 167.00 0.001670 9.96 4015.30 362.40 0.53 Below Prado 72601 190yr ACOE 40000.00 153.24 165.18 161.08 166.73 0.001650 9.97 4011.23 357.56 0.52 Below Prado 72401 190yr ACOE 40000.00 152.84 164.90 160.66 166.38 0.001577 9.76 4098.79 365.51 0.51 Below Prado 72201 190yr ACOE 40000.00 152.44 164.63 160.23 166.06 0.001504 9.62 4159.37 365.64 0.50 Below Prado 72027 190yr ACOE 40000.00 152.04 164.43 159.76 165.79 0.001386 9.35 4279.43 368.81 0.48 Below Prado 71854* 190yr ACOE 40000.00 151.64 164.22 159.37 165.55 0.001326 9.23 4332.02 367.54 0.47 Below Prado 71772 190yr ACOE 40000.00 151.46 164.12 159.22 165.43 0.001307 9.21 4345.14 366.50 0.47 Below Prado 71718 190yr ACOE 40000.00 151.32 164.06 159.08 165.36 0.001286 9.17 4361.38 365.20 0.47 Below Prado 71681 190yr ACOE 40000.00 151.24 164.00 159.03 165.31 0.001294 9.20 4346.52 363.91 0.47 Below Prado 71481* 190yr ACOE 40000.00 150.79 163.64 158.81 165.04 0.001370 9.48 4220.55 352.95 0.48 Below Prado 71281 190yr ACOE 40000.00 150.34 163.23 158.61 164.74 0.001489 9.86 4054.78 339.71 0.50 Below Prado 71201 190yr ACOE 40000.00 150.14 163.05 158.62 164.61 0.001650 10.02 3992.17 353.41 0.53 Below Prado 71081* 190yr ACOE 40000.00 149.74 162.91 158.56 164.39 0.001544 9.77 4092.49 358.52 0.51 Below Prado 70961 190yr ACOE 40000.00 149.34 162.84 158.04 164.18 0.001350 9.29 4307.76 368.04 0.48 Below Prado 70894 Bridge
Below Prado 70827 190yr ACOE 40000.00 149.34 162.45 157.77 163.86 0.001405 9.51 4206.27 354.75 0.49 Below Prado 70714 190yr ACOE 40000.00 148.94 162.37 157.28 163.68 0.001260 9.16 4367.03 360.67 0.46 Below Prado 70601 190yr ACOE 40000.00 148.54 162.28 156.67 163.52 0.001172 8.94 4472.32 362.66 0.45 Below Prado 70434* 190yr ACOE 40000.00 148.31 162.10 156.41 163.32 0.001108 8.87 4507.55 354.74 0.44 Below Prado 70267* 190yr ACOE 40000.00 148.07 161.62 156.60 163.09 0.001374 9.73 4110.69 331.00 0.49 Below Prado 70101 190yr ACOE 40000.00 147.84 161.25 156.51 162.84 0.001515 10.13 3946.90 321.50 0.51 HEC-RAS Plan: Existing_Topo_ACOE_Extend River: Santa Ana River Reach: Below Prado Profile: 190yr ACOE (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 69934* 190yr ACOE 41000.00 147.41 161.05 155.88 162.58 0.001397 9.90 4141.24 321.20 0.49 Below Prado 69767* 190yr ACOE 41000.00 146.97 160.69 155.87 162.32 0.001511 10.25 3998.37 319.04 0.51 Below Prado 69601 190yr ACOE 41000.00 146.54 160.50 155.35 162.06 0.001398 10.01 4096.90 319.10 0.49 Below Prado 69366 190yr ACOE 41000.00 146.17 160.26 154.99 161.71 0.001318 9.66 4243.97 334.53 0.48 Below Prado 69341 Bridge
Below Prado 69313 190yr ACOE 41000.00 146.00 159.55 154.81 161.13 0.001506 10.10 4059.71 330.82 0.51 Below Prado 69200 190yr ACOE 41000.00 145.78 159.25 154.71 160.94 0.001665 10.43 3929.91 328.42 0.53 Below Prado 69176* 190yr ACOE 41000.00 145.73 159.14 154.69 160.90 0.001768 10.62 3861.75 329.05 0.55 Below Prado 69152* 190yr ACOE 41000.00 145.68 159.11 154.58 160.85 0.001640 10.59 3873.08 312.83 0.53 Below Prado 69128* 190yr ACOE 41000.00 145.63 159.07 154.55 160.81 0.001643 10.58 3875.05 313.93 0.53 Below Prado 69104* 190yr ACOE 41000.00 145.58 159.02 154.55 160.77 0.001661 10.62 3860.46 313.87 0.53 Below Prado 69080* 190yr ACOE 41000.00 145.54 158.97 154.57 160.73 0.001684 10.64 3851.77 315.79 0.54 Below Prado 69056* 190yr ACOE 41000.00 145.49 158.94 154.48 160.68 0.001655 10.57 3877.79 316.73 0.53 Below Prado 69032* 190yr ACOE 41000.00 145.44 158.92 154.38 160.64 0.001628 10.52 3898.27 317.17 0.53 Below Prado 69009 190yr ACOE 41000.00 145.39 158.93 154.21 160.58 0.001551 10.31 3976.90 321.20 0.52 Below Prado 69004 190yr ACOE 41000.00 145.38 158.93 154.19 160.56 0.001536 10.26 3995.60 322.61 0.51 Below Prado 68999 190yr ACOE 41000.00 145.37 158.94 154.12 160.54 0.001497 10.15 4038.23 324.75 0.51 Below Prado 68994 190yr ACOE 41000.00 145.36 158.95 154.04 160.52 0.001466 10.05 4079.46 328.15 0.50 Below Prado 68989 190yr ACOE 41000.00 145.35 158.96 153.99 160.50 0.001434 9.95 4121.20 330.97 0.50 Below Prado 68985 190yr ACOE 41000.00 145.34 158.97 153.94 160.48 0.001403 9.86 4159.96 333.49 0.49 Below Prado 68977 Inl Struct
Below Prado 68969 190yr ACOE 41000.00 135.14 152.76 144.25 153.80 0.002021 8.21 4993.54 315.57 0.36 Below Prado 68964 190yr ACOE 41000.00 135.14 152.78 143.99 153.78 0.001929 8.03 5106.65 318.20 0.35 Below Prado 68959 190yr ACOE 41000.00 135.14 152.76 144.11 153.77 0.001940 8.06 5085.98 320.70 0.36 Below Prado 68955 190yr ACOE 41000.00 135.14 152.75 144.25 153.76 0.001974 8.09 5071.08 323.19 0.36 Below Prado 68950 190yr ACOE 41000.00 135.14 152.75 144.14 153.75 0.001911 8.00 5127.06 325.75 0.36 Below Prado 68945 190yr ACOE 41000.00 135.14 152.75 144.16 153.73 0.001890 7.96 5151.62 327.78 0.35 Below Prado 68940 190yr ACOE 41000.00 135.14 152.75 144.13 153.72 0.001874 7.93 5169.93 328.70 0.35 Below Prado 68936 190yr ACOE 41000.00 135.14 152.74 144.12 153.71 0.001862 7.91 5182.99 329.47 0.35 Below Prado 68931 190yr ACOE 41000.00 135.14 152.74 144.06 153.70 0.001841 7.88 5204.06 330.19 0.35 Below Prado 68926 190yr ACOE 41000.00 135.14 152.72 144.11 153.69 0.001851 7.90 5191.91 330.68 0.35 Below Prado 68922 190yr ACOE 41000.00 135.14 152.71 144.11 153.68 0.001868 7.92 5175.27 329.01 0.35 Below Prado 68916 190yr ACOE 41000.00 138.07 152.13 146.83 153.62 0.003693 9.78 4191.22 326.09 0.48 Below Prado 68808* 190yr ACOE 41000.00 137.85 151.20 147.48 153.26 0.002085 11.53 3556.58 304.49 0.59 Below Prado 68700 190yr ACOE 41000.00 137.64 151.28 146.54 152.95 0.001557 10.37 3953.71 317.00 0.52 Below Prado 68547* 190yr ACOE 41000.00 137.29 151.14 146.34 152.68 0.001496 9.97 4112.47 341.42 0.51 Below Prado 68395 190yr ACOE 41000.00 136.94 150.82 146.05 152.44 0.001542 10.22 4011.78 327.99 0.52 Below Prado 68222 Bridge
Below Prado 68050 190yr ACOE 41000.00 136.40 149.14 145.46 151.17 0.002060 11.43 3587.55 306.96 0.59 Below Prado 67866* 190yr ACOE 41000.00 136.07 148.73 145.12 150.79 0.002109 11.50 3565.68 307.85 0.60 Below Prado 67683* 190yr ACOE 41000.00 135.71 148.42 144.66 150.39 0.002009 11.26 3641.43 313.06 0.58 Below Prado 67500 190yr ACOE 41000.00 135.34 148.07 144.27 150.01 0.001973 11.19 3665.50 313.98 0.58 Below Prado 67341 190yr ACOE 41000.00 134.98 147.74 143.94 149.70 0.001984 11.22 3652.65 312.47 0.58 Below Prado 67313 190yr ACOE 41000.00 134.91 147.68 143.87 149.64 0.001979 11.23 3650.81 311.25 0.58 Below Prado 67166* 190yr ACOE 41000.00 134.58 147.42 143.49 149.34 0.001917 11.12 3685.70 311.14 0.57 Below Prado 67000 190yr ACOE 41000.00 134.20 147.31 142.96 148.97 0.001646 10.34 3965.54 329.00 0.53 Below Prado 66922 190yr ACOE 41000.00 134.14 147.16 142.72 148.84 0.001629 10.38 3949.64 323.23 0.52 Below Prado 66884 Bridge
Below Prado 66847 190yr ACOE 41000.00 133.94 146.31 142.79 148.27 0.002113 11.24 3647.49 324.43 0.59 Below Prado 66723* 190yr ACOE 41000.00 133.64 145.99 142.69 148.00 0.002328 11.36 3608.04 342.86 0.62 Below Prado 66600 190yr ACOE 41000.00 133.34 145.78 142.08 147.71 0.002013 11.15 3676.47 321.30 0.58 Below Prado 66433* 190yr ACOE 41000.00 133.01 145.43 141.76 147.37 0.002026 11.19 3665.20 320.28 0.58 Below Prado 66266* 190yr ACOE 41000.00 132.67 145.08 141.42 147.04 0.002032 11.21 3657.96 319.35 0.58 Below Prado 66100 190yr ACOE 41000.00 132.34 144.73 141.10 146.70 0.002048 11.25 3645.80 318.40 0.59 Below Prado 65933* 190yr ACOE 41000.00 132.01 144.39 140.77 146.35 0.002048 11.23 3649.72 319.44 0.59 Below Prado 65766* 190yr ACOE 41000.00 131.67 144.06 140.42 146.01 0.002041 11.21 3658.00 320.56 0.58 Appendix C

Appendix C – Proposed Condition HEC-RAS Output

HEC-RAS Plan: Proposed_Cut_Extend_v2 River: Santa Ana River Reach: Below Prado Profile: 190yr ACOE Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 77600 190yr ACOE 40000.00 172.94 184.18 180.49 185.74 0.001799 10.01 3996.02 379.15 0.54 Below Prado 77433* 190yr ACOE 40000.00 172.57 183.85 180.18 185.43 0.001819 10.08 3966.48 375.21 0.55 Below Prado 77266* 190yr ACOE 40000.00 172.21 183.51 179.87 185.12 0.001854 10.19 3927.23 371.21 0.55 Below Prado 77100 190yr ACOE 40000.00 171.84 183.16 179.57 184.80 0.001889 10.29 3888.74 367.16 0.56 Below Prado 76933* 190yr ACOE 40000.00 171.51 182.85 179.24 184.48 0.001871 10.24 3905.58 368.61 0.55 Below Prado 76766* 190yr ACOE 40000.00 171.17 182.56 178.89 184.17 0.001842 10.18 3930.32 370.24 0.55 Below Prado 76600 190yr ACOE 40000.00 170.84 182.27 178.54 183.86 0.001817 10.12 3953.16 371.94 0.55 Below Prado 76433* 190yr ACOE 40000.00 170.37 181.93 178.18 183.55 0.001839 10.21 3917.16 366.66 0.55 Below Prado 76266* 190yr ACOE 40000.00 169.91 181.57 177.84 183.24 0.001877 10.34 3867.90 360.45 0.56 Below Prado 76100 190yr ACOE 40000.00 169.44 181.21 177.50 182.92 0.001877 10.47 3818.72 348.69 0.56 Below Prado 75900* 190yr ACOE 40000.00 169.14 180.85 177.12 182.53 0.001944 10.40 3845.80 364.66 0.56 Below Prado 75700* 190yr ACOE 40000.00 168.84 180.48 176.76 182.13 0.001922 10.32 3875.39 368.69 0.56 Below Prado 75500* 190yr ACOE 40000.00 168.54 180.11 176.39 181.74 0.001899 10.24 3906.31 372.80 0.56 Below Prado 75300* 190yr ACOE 40000.00 168.24 179.75 176.03 181.36 0.001875 10.15 3939.12 377.23 0.55 Below Prado 75100 190yr ACOE 40000.00 167.94 179.40 175.67 180.98 0.001846 10.06 3974.76 381.51 0.55 Below Prado 74969 190yr ACOE 40000.00 167.24 179.27 175.08 180.72 0.001564 9.65 4144.74 366.63 0.51 Below Prado 74927 Bridge
Below Prado 74886 190yr ACOE 40000.00 167.24 178.87 175.12 180.40 0.001775 9.92 4034.17 382.80 0.54 Below Prado 74862* 190yr ACOE 40000.00 167.19 178.78 175.12 180.35 0.001872 10.06 3976.11 382.99 0.55 Below Prado 74839* 190yr ACOE 40000.00 167.13 178.72 175.04 180.31 0.001882 10.10 3959.05 380.59 0.55 Below Prado 74815* 190yr ACOE 40000.00 167.08 178.73 174.71 180.24 0.001719 9.85 4060.95 377.07 0.53 Below Prado 74792* 190yr ACOE 40000.00 167.03 178.66 174.74 180.20 0.001768 9.95 4022.06 380.21 0.54 Below Prado 74768 190yr ACOE 40000.00 166.97 178.66 174.59 180.14 0.001619 9.77 4094.54 371.30 0.52 Below Prado 74745* 190yr ACOE 40000.00 166.92 178.65 174.49 180.09 0.001565 9.63 4152.00 375.08 0.51 Below Prado 74721* 190yr ACOE 40000.00 166.87 178.63 174.43 180.05 0.001549 9.58 4176.26 378.08 0.51 Below Prado 74697 190yr ACOE 40000.00 166.81 178.57 174.43 180.01 0.001576 9.63 4152.59 377.82 0.51 Below Prado 74674* 190yr ACOE 40000.00 166.76 178.48 174.50 179.97 0.001658 9.80 4081.43 375.74 0.52 Below Prado 74650* 190yr ACOE 40000.00 166.71 178.39 174.57 179.92 0.001740 9.95 4020.95 375.40 0.54 Below Prado 74627* 190yr ACOE 40000.00 166.65 178.30 174.46 179.88 0.001816 10.08 3969.80 375.50 0.55 Below Prado 74603 190yr ACOE 40000.00 166.60 178.24 174.40 179.84 0.001777 10.16 3938.68 361.70 0.54 Below Prado 74580* 190yr ACOE 40000.00 166.55 178.20 174.36 179.79 0.001763 10.12 3951.66 362.67 0.54 Below Prado 74556 190yr ACOE 40000.00 166.49 178.21 174.19 179.73 0.001666 9.91 4038.06 366.70 0.53 Below Prado 74552* 190yr ACOE 40000.00 166.48 178.20 174.18 179.72 0.001659 9.88 4047.94 367.80 0.53 Below Prado 74547 190yr ACOE 40000.00 166.47 178.20 174.17 179.71 0.001660 9.87 4051.10 368.70 0.53 Below Prado 74542 190yr ACOE 40000.00 166.46 178.21 174.12 179.69 0.001622 9.77 4093.05 371.97 0.52 Below Prado 74537 190yr ACOE 40000.00 166.45 178.22 174.06 179.67 0.001578 9.66 4142.27 375.46 0.51 Below Prado 74533 190yr ACOE 40000.00 166.44 178.21 174.06 179.66 0.001584 9.67 4136.34 375.07 0.51 Below Prado 74524 Inl Struct
Below Prado 74515 190yr ACOE 40000.00 154.19 169.84 162.21 170.77 0.002062 7.75 5159.62 359.45 0.36 Below Prado 74510 190yr ACOE 40000.00 154.19 169.84 162.23 170.76 0.002041 7.71 5190.27 362.99 0.36 Below Prado 74505 190yr ACOE 40000.00 154.19 169.84 162.21 170.75 0.002004 7.64 5237.40 366.39 0.36 Below Prado 74500 190yr ACOE 40000.00 154.19 169.84 162.18 170.73 0.001970 7.59 5273.32 369.54 0.35 Below Prado 74496 190yr ACOE 40000.00 154.19 169.83 162.17 170.72 0.001944 7.56 5293.05 370.47 0.35 Below Prado 74491 190yr ACOE 40000.00 154.19 169.82 162.15 170.71 0.001934 7.56 5287.70 370.01 0.35 Below Prado 74486 190yr ACOE 40000.00 154.19 169.81 162.15 170.70 0.001930 7.57 5282.51 369.50 0.35 Below Prado 74481 190yr ACOE 40000.00 154.19 169.80 162.13 170.69 0.001918 7.57 5284.02 369.03 0.35 Below Prado 74477 190yr ACOE 40000.00 154.19 169.79 162.13 170.68 0.001927 7.59 5273.34 368.78 0.35 Below Prado 74469 190yr ACOE 40000.00 157.29 169.07 165.05 170.60 0.004643 9.93 4029.06 365.37 0.53 Below Prado 74313* 190yr ACOE 40000.00 156.94 168.56 164.77 170.17 0.001784 10.16 3938.15 363.22 0.54 Below Prado 74157* 190yr ACOE 40000.00 156.59 168.29 164.42 169.89 0.001764 10.16 3937.55 359.28 0.54 Below Prado 74001 190yr ACOE 40000.00 156.24 168.03 164.10 169.61 0.001729 10.10 3960.68 359.47 0.54 Below Prado 73801* 190yr ACOE 40000.00 155.79 167.72 163.62 169.26 0.001647 9.94 4024.36 360.27 0.52 Below Prado 73601 190yr ACOE 40000.00 155.34 167.47 163.12 168.92 0.001513 9.63 4152.78 365.69 0.50 Below Prado 73467* 190yr ACOE 40000.00 155.19 167.17 163.16 168.70 0.001669 9.89 4042.63 368.41 0.53 Below Prado 73334 190yr ACOE 40000.00 155.04 166.97 162.99 168.46 0.001715 9.81 4076.73 381.19 0.53 Below Prado 73324 Bridge
Below Prado 73314 190yr ACOE 40000.00 155.04 166.50 162.94 168.14 0.001878 10.26 3899.77 364.48 0.55 Below Prado 73207* 190yr ACOE 40000.00 154.69 166.28 162.74 167.94 0.001907 10.33 3873.06 363.40 0.56 Below Prado 73101 190yr ACOE 40000.00 154.34 166.16 162.23 167.71 0.001762 9.99 4005.66 371.42 0.54 Below Prado 72934* 190yr ACOE 40000.00 153.97 165.89 161.79 167.42 0.001646 9.92 4032.17 362.25 0.52 Below Prado 72767 190yr ACOE 40000.00 153.61 165.77 161.36 167.11 0.001388 9.30 4354.32 398.19 0.48 Below Prado 72601 190yr ACOE 40000.00 153.24 165.42 161.21 166.85 0.001604 9.59 4187.81 396.69 0.51 Below Prado 72401 190yr ACOE 40000.00 152.84 165.29 160.48 166.50 0.001216 8.89 4572.01 406.86 0.46 Below Prado 72201 190yr ACOE 40000.00 152.44 165.05 160.09 166.26 0.001194 8.85 4567.27 397.34 0.45 Below Prado 72027 190yr ACOE 40000.00 152.04 164.87 159.65 166.05 0.001165 8.75 4594.87 396.70 0.45 Below Prado 71854* 190yr ACOE 40000.00 151.64 164.63 159.29 165.85 0.001151 8.87 4510.07 357.99 0.44 Below Prado 71772 190yr ACOE 40000.00 151.46 164.62 158.79 165.72 0.001012 8.43 4744.44 367.10 0.41 Below Prado 71740 Bridge
Below Prado 71718 190yr ACOE 40000.00 151.32 164.29 158.65 165.43 0.001063 8.56 4671.68 366.75 0.42 Below Prado 71681 190yr ACOE 40000.00 151.24 164.11 158.97 165.37 0.001213 9.02 4433.46 357.07 0.45 Below Prado 71481* 190yr ACOE 40000.00 150.79 163.73 158.81 165.11 0.001339 9.41 4251.09 353.30 0.48 Below Prado 71281 190yr ACOE 40000.00 150.34 163.33 158.60 164.82 0.001449 9.78 4089.27 340.04 0.50 Below Prado 71201 190yr ACOE 40000.00 150.14 163.16 158.62 164.69 0.001599 9.92 4032.16 353.80 0.52 Below Prado 71081* 190yr ACOE 40000.00 149.74 163.03 158.56 164.48 0.001495 9.67 4135.12 358.95 0.50 Below Prado 70961 190yr ACOE 40000.00 149.34 162.96 158.04 164.27 0.001306 9.19 4352.90 368.60 0.47 Below Prado 70894 Bridge
Below Prado 70827 190yr ACOE 40000.00 149.34 162.59 157.77 163.96 0.001354 9.40 4254.97 355.01 0.48 Below Prado 70714 190yr ACOE 40000.00 148.94 162.50 157.38 163.79 0.001255 9.09 4399.17 367.62 0.46 Below Prado 70601 190yr ACOE 40000.00 148.54 162.48 156.80 163.61 0.001050 8.53 4690.21 376.51 0.43 Below Prado 70434* 190yr ACOE 40000.00 148.31 162.32 156.45 163.43 0.001015 8.45 4731.95 375.37 0.42 Below Prado 70267* 190yr ACOE 40000.00 148.07 161.68 156.84 163.19 0.001455 9.88 4049.40 331.11 0.50 HEC-RAS Plan: Proposed_Cut_Extend_v2 River: Santa Ana River Reach: Below Prado Profile: 190yr ACOE (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 70101 190yr ACOE 40000.00 147.84 161.08 157.06 162.89 0.001915 10.77 3714.84 329.03 0.56 Below Prado 69934* 190yr ACOE 41000.00 147.41 160.98 156.03 162.54 0.001461 10.02 4091.22 321.47 0.50 Below Prado 69767* 190yr ACOE 41000.00 146.97 160.63 155.87 162.28 0.001535 10.31 3978.42 318.82 0.51 Below Prado 69601 190yr ACOE 41000.00 146.54 160.44 155.35 162.01 0.001420 10.06 4075.78 318.83 0.50 Below Prado 69366 190yr ACOE 41000.00 146.17 160.24 154.83 161.64 0.001276 9.52 4308.77 334.38 0.47 Below Prado 69341 Bridge
Below Prado 69313 190yr ACOE 41000.00 146.00 159.62 154.68 161.13 0.001430 9.87 4152.33 331.13 0.49 Below Prado 69200 190yr ACOE 41000.00 145.78 159.25 154.71 160.94 0.001665 10.43 3929.85 328.42 0.53 Below Prado 69176* 190yr ACOE 41000.00 145.73 159.14 154.69 160.90 0.001768 10.62 3861.69 329.05 0.55 Below Prado 69152* 190yr ACOE 41000.00 145.68 159.11 154.59 160.85 0.001640 10.59 3873.04 312.83 0.53 Below Prado 69128* 190yr ACOE 41000.00 145.63 159.07 154.55 160.81 0.001643 10.58 3875.00 313.93 0.53 Below Prado 69104* 190yr ACOE 41000.00 145.58 159.02 154.55 160.77 0.001661 10.62 3860.41 313.87 0.53 Below Prado 69080* 190yr ACOE 41000.00 145.54 158.97 154.57 160.73 0.001684 10.64 3851.72 315.79 0.54 Below Prado 69056* 190yr ACOE 41000.00 145.49 158.94 154.48 160.68 0.001655 10.57 3877.73 316.73 0.53 Below Prado 69032* 190yr ACOE 41000.00 145.44 158.92 154.40 160.64 0.001628 10.52 3898.21 317.17 0.53 Below Prado 69009 190yr ACOE 41000.00 145.39 158.93 154.21 160.58 0.001551 10.31 3976.84 321.20 0.52 Below Prado 69004 190yr ACOE 41000.00 145.38 158.93 154.18 160.56 0.001536 10.26 3995.54 322.61 0.51 Below Prado 68999 190yr ACOE 41000.00 145.37 158.94 154.11 160.54 0.001497 10.15 4038.17 324.75 0.51 Below Prado 68994 190yr ACOE 41000.00 145.36 158.95 154.06 160.52 0.001466 10.05 4079.40 328.15 0.50 Below Prado 68989 190yr ACOE 41000.00 145.35 158.96 153.99 160.50 0.001434 9.95 4121.14 330.98 0.50 Below Prado 68985 190yr ACOE 41000.00 145.34 158.97 153.93 160.48 0.001403 9.86 4159.90 333.49 0.49 Below Prado 68977 Inl Struct
Below Prado 68969 190yr ACOE 41000.00 135.14 152.82 144.25 153.86 0.001996 8.18 5014.08 315.83 0.36 Below Prado 68964 190yr ACOE 41000.00 135.14 152.84 143.99 153.84 0.001906 8.00 5127.28 318.48 0.35 Below Prado 68959 190yr ACOE 41000.00 135.14 152.83 144.12 153.83 0.001916 8.03 5106.87 320.97 0.35 Below Prado 68955 190yr ACOE 41000.00 135.14 152.83 144.17 153.81 0.001888 7.97 5144.60 326.05 0.35 Below Prado 68950 190yr ACOE 41000.00 135.14 152.82 144.14 153.81 0.001886 7.96 5148.85 326.01 0.35 Below Prado 68945 190yr ACOE 41000.00 135.14 152.82 144.16 153.79 0.001866 7.92 5173.57 328.03 0.35 Below Prado 68940 190yr ACOE 41000.00 135.14 152.81 144.13 153.78 0.001850 7.90 5191.97 328.99 0.35 Below Prado 68936 190yr ACOE 41000.00 135.14 152.81 144.11 153.77 0.001838 7.88 5205.13 329.77 0.35 Below Prado 68931 190yr ACOE 41000.00 135.14 152.80 144.07 153.76 0.001816 7.85 5226.26 330.49 0.35 Below Prado 68926 190yr ACOE 41000.00 135.14 152.79 144.10 153.75 0.001826 7.86 5214.20 330.98 0.35 Below Prado 68922 190yr ACOE 41000.00 135.14 152.78 144.11 153.74 0.001844 7.89 5197.52 329.27 0.35 Below Prado 68916 190yr ACOE 41000.00 138.06 152.21 146.82 153.68 0.003620 9.72 4218.61 326.39 0.48 Below Prado 68808* 190yr ACOE 41000.00 137.85 151.31 147.48 153.33 0.002028 11.42 3589.22 305.08 0.59 Below Prado 68700 190yr ACOE 41000.00 137.64 151.39 146.55 153.03 0.001517 10.28 3987.22 317.51 0.51 Below Prado 68547* 190yr ACOE 41000.00 137.29 151.25 146.35 152.76 0.001454 9.88 4150.78 342.12 0.50 Below Prado 68395 190yr ACOE 41000.00 136.94 150.94 146.03 152.53 0.001495 10.12 4052.14 328.65 0.51 Below Prado 68222 Bridge
Below Prado 68050 190yr ACOE 41000.00 136.40 149.49 145.40 151.36 0.001853 10.97 3738.23 314.74 0.56 Below Prado 67866* 190yr ACOE 41000.00 136.07 149.06 145.13 151.00 0.001970 11.18 3666.94 313.91 0.58 Below Prado 67683* 190yr ACOE 41000.00 135.71 148.70 144.78 150.62 0.002131 11.12 3686.72 335.92 0.59 Below Prado 67500 190yr ACOE 41000.00 135.34 148.38 144.30 150.23 0.001868 10.92 3755.03 319.78 0.56 Below Prado 67341 190yr ACOE 41000.00 134.98 147.85 144.14 149.90 0.002062 11.49 3569.11 303.12 0.59 Below Prado 67324 Bridge
Below Prado 67313 190yr ACOE 41000.00 134.91 147.59 144.07 149.71 0.002173 11.69 3508.21 302.02 0.60 Below Prado 67166* 190yr ACOE 41000.00 134.58 147.43 143.50 149.35 0.001912 11.11 3690.17 311.22 0.57 Below Prado 67000 190yr ACOE 41000.00 134.20 147.32 142.96 148.98 0.001640 10.33 3970.70 329.03 0.52 Below Prado 66922 190yr ACOE 41000.00 134.14 147.11 142.86 148.84 0.001713 10.55 3886.49 323.09 0.54 Below Prado 66884 Bridge
Below Prado 66847 190yr ACOE 41000.00 133.94 146.23 143.06 148.31 0.002315 11.57 3543.61 324.26 0.62 Below Prado 66723* 190yr ACOE 41000.00 133.64 145.99 142.69 148.00 0.002328 11.36 3608.04 342.86 0.62 Below Prado 66600 190yr ACOE 41000.00 133.34 145.78 142.08 147.71 0.002013 11.15 3676.47 321.30 0.58 Below Prado 66433* 190yr ACOE 41000.00 133.01 145.43 141.76 147.37 0.002026 11.19 3665.20 320.28 0.58 Below Prado 66266* 190yr ACOE 41000.00 132.67 145.08 141.42 147.04 0.002032 11.21 3657.96 319.35 0.58 Below Prado 66100 190yr ACOE 41000.00 132.34 144.73 141.10 146.70 0.002048 11.25 3645.80 318.40 0.59 Below Prado 65933* 190yr ACOE 41000.00 132.01 144.39 140.77 146.35 0.002048 11.23 3649.72 319.44 0.59 Below Prado 65766* 190yr ACOE 41000.00 131.67 144.06 140.42 146.01 0.002041 11.21 3658.00 320.56 0.58 Appendix D

Appendix D – Dam Deflation Scenarios HEC-RAS
Output

Appendix D
North Deflation HEC-RAS Model Output

HEC-RAS Plan: North_Short River: Santa Ana River Reach: Below Prado Profile: Max WS Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 69601 Max WS 2832.88 144.20 146.97 147.18 0.001486 3.70 766.32 283.34 0.40 Below Prado 69366 Max WS 2832.24 143.83 146.63 145.33 146.84 0.001444 3.68 769.64 280.08 0.39 Below Prado 69341 Bridge
Below Prado 69313 Max WS 2832.21 143.66 146.12 146.39 0.002219 4.20 675.05 278.62 0.48 Below Prado 69200 Max WS 2831.55 143.44 145.85 146.14 0.002354 4.28 662.57 279.14 0.49 Below Prado 69176* Max WS 2831.38 143.39 145.80 146.08 0.002391 4.29 660.46 279.24 0.49 Below Prado 69152* Max WS 2831.20 143.34 145.74 146.02 0.002421 4.30 658.00 279.34 0.49 Below Prado 69128* Max WS 2831.11 143.29 145.68 145.97 0.002456 4.32 655.26 279.44 0.50 Below Prado 69104* Max WS 2830.94 143.24 145.61 145.91 0.002495 4.34 652.18 279.56 0.50 Below Prado 69080* Max WS 2830.89 143.20 145.55 145.85 0.002593 4.39 644.76 279.64 0.51 Below Prado 69056* Max WS 2830.74 143.15 145.48 145.78 0.002655 4.42 640.31 279.76 0.52 Below Prado 69032* Max WS 2830.55 143.10 145.41 145.72 0.002727 4.46 635.22 279.91 0.52 Below Prado 69009 Max WS 2830.43 143.05 145.34 145.65 0.002813 4.50 629.42 280.05 0.53 Below Prado 69004* Max WS 2830.34 143.04 145.32 145.64 0.002832 4.51 628.17 280.09 0.53 Below Prado 68999* Max WS 2830.39 143.03 145.31 145.63 0.002852 4.52 626.86 280.11 0.53 Below Prado 68994* Max WS 2830.37 143.02 145.29 145.61 0.002873 4.52 625.52 280.15 0.53 Below Prado 68989* Max WS 2830.35 143.01 145.28 145.60 0.002895 4.53 624.13 280.19 0.54 Below Prado 68985 Max WS 2830.36 143.00 145.26 144.50 145.58 0.002917 4.55 622.72 280.22 0.54 Below Prado 68977 Inl Struct
Below Prado 68969 Max WS 2830.15 132.80 138.62 138.67 0.000344 1.74 1630.75 280.00 0.13 Below Prado 68964* Max WS 2830.14 132.80 138.62 138.67 0.000347 1.74 1624.39 279.00 0.13 Below Prado 68959* Max WS 2830.13 132.80 138.62 138.67 0.000349 1.75 1618.01 278.00 0.13 Below Prado 68955* Max WS 2830.12 132.80 138.62 138.67 0.000352 1.76 1611.61 277.00 0.13 Below Prado 68950* Max WS 2830.07 132.80 138.62 138.66 0.000356 1.76 1605.24 276.00 0.13 Below Prado 68945* Max WS 2830.01 132.80 138.61 138.66 0.000359 1.77 1598.85 275.00 0.13 Below Prado 68940* Max WS 2829.95 132.80 138.61 138.66 0.000362 1.78 1592.55 274.64 0.13 Below Prado 68936* Max WS 2830.04 132.80 138.61 138.66 0.000366 1.78 1586.73 275.03 0.13 Below Prado 68931* Max WS 2830.07 132.80 138.61 138.66 0.000370 1.79 1581.49 275.38 0.13 Below Prado 68926* Max WS 2830.05 132.80 138.61 138.66 0.000373 1.79 1576.84 275.70 0.13 Below Prado 68922 Max WS 2830.02 132.80 138.60 138.65 0.000376 1.80 1572.72 275.98 0.13 Below Prado 68916 Max WS 2829.98 135.73 138.44 138.67 0.004004 3.61 751.49 285.36 0.39 Below Prado 68808* Max WS 2829.59 135.51 138.11 138.35 0.001832 3.94 718.40 282.61 0.44 Below Prado 68700 Max WS 2829.47 135.30 137.92 138.16 0.001800 3.93 720.75 281.07 0.43 Below Prado 68547* Max WS 2829.45 134.95 137.68 137.90 0.001560 3.76 753.07 281.70 0.41 Below Prado 68395 Max WS 2830.01 134.60 137.49 136.10 137.68 0.001295 3.55 797.43 282.62 0.37 Below Prado 68222 Bridge
Below Prado 68050 Max WS 2826.61 134.10 136.62 136.88 0.002023 4.06 695.75 281.49 0.46 Below Prado 67866* Max WS 2822.49 133.73 136.26 136.51 0.002015 4.06 695.26 280.70 0.45 Below Prado 67683* Max WS 2816.79 133.37 135.88 136.14 0.002045 4.08 690.68 279.88 0.46 Below Prado 67500 Max WS 2809.71 133.00 135.51 135.77 0.002046 4.08 688.80 279.13 0.46 Below Prado 67333* Max WS 2804.69 132.62 135.21 135.45 0.001836 3.92 715.27 283.81 0.44 Below Prado 67166* Max WS 2796.94 132.24 134.95 135.16 0.001568 3.70 756.14 291.15 0.40 Below Prado 67000 Max WS 2793.96 131.86 134.75 134.93 0.001265 3.40 821.11 304.87 0.37 Below Prado 66922 Max WS 2793.29 131.80 134.63 133.29 134.83 0.001341 3.56 784.60 284.16 0.38 Below Prado 66884 Bridge
Below Prado 66847 Max WS 2790.75 131.60 134.01 134.29 0.002290 4.20 664.77 280.97 0.48 Below Prado 66723* Max WS 2784.43 131.30 133.75 134.01 0.002181 4.14 673.09 280.31 0.47 Below Prado 66600 Max WS 2778.14 131.00 133.50 133.75 0.002018 4.04 688.03 280.31 0.45 Below Prado 66433* Max WS 2770.49 130.67 133.17 133.42 0.002022 4.04 686.31 280.10 0.45 Below Prado 66266* Max WS 2763.44 130.33 132.84 133.09 0.001983 4.01 689.19 279.96 0.45 Below Prado 66100 Max WS 2755.96 130.00 132.51 132.76 0.001960 3.99 690.34 279.81 0.45 Below Prado 65933* Max WS 2749.48 129.67 132.19 132.44 0.001919 3.96 693.95 280.07 0.44 Below Prado 65766* Max WS 2742.86 129.33 131.89 132.13 0.001815 3.89 705.08 280.46 0.43 Below Prado 65600 Max WS 2737.64 129.00 131.61 131.84 0.001697 3.81 718.98 280.90 0.42 Below Prado 65425* Max WS 2733.25 128.73 131.30 131.53 0.001779 3.86 708.25 280.96 0.43 Below Prado 65250* Max WS 2730.12 128.45 130.97 131.21 0.001890 3.93 694.94 280.95 0.44 Below Prado 65075* Max WS 2727.03 128.18 130.60 130.86 0.002174 4.10 665.64 280.69 0.47 Below Prado 64900 Max WS 2723.44 127.90 130.08 130.40 0.003044 4.54 600.41 279.83 0.55 Below Prado 64734* Max WS 2720.85 127.34 129.64 129.93 0.002662 4.36 624.24 279.25 0.51 Below Prado 64568 Max WS 2719.99 126.78 129.25 129.52 0.002291 4.17 652.91 279.14 0.48 Below Prado 64559* Max WS 2720.01 126.78 129.23 129.50 0.002306 4.17 651.60 279.08 0.48 Below Prado 64550* Max WS 2719.94 126.78 129.21 129.48 0.002315 4.18 650.76 279.03 0.48 Below Prado 64541* Max WS 2719.93 126.79 129.18 129.46 0.002381 4.22 645.22 278.94 0.49 Below Prado 64532* Max WS 2719.94 126.79 129.16 129.44 0.002418 4.24 642.18 278.88 0.49 Below Prado 64522* Max WS 2719.92 126.79 129.13 129.42 0.002479 4.27 637.29 278.80 0.50 Below Prado 64513* Max WS 2719.91 126.79 129.10 129.39 0.002547 4.30 632.05 278.73 0.50 Below Prado 64504* Max WS 2719.90 126.80 129.07 129.37 0.002691 4.38 621.64 278.61 0.52 Below Prado 64495 Max WS 2719.90 126.80 129.04 129.34 0.002811 4.43 613.46 278.53 0.53 Below Prado 64490* Max WS 2719.89 126.80 129.02 129.33 0.002884 4.47 608.70 278.46 0.53 Below Prado 64486 Max WS 2719.88 126.80 129.00 128.26 129.32 0.002965 4.51 603.61 278.41 0.54 Below Prado 64478 Inl Struct
Below Prado 64470 Max WS 2698.47 117.80 123.82 123.86 0.000302 1.66 1625.72 270.00 0.12 Below Prado 64465* Max WS 2698.86 117.80 123.82 123.86 0.000302 1.66 1625.32 270.00 0.12 Below Prado 64460* Max WS 2698.46 117.80 123.82 123.86 0.000302 1.66 1624.94 270.00 0.12 Below Prado 64455* Max WS 2698.84 117.80 123.82 123.86 0.000303 1.66 1624.54 270.00 0.12 Below Prado 64450* Max WS 2698.45 117.80 123.82 123.86 0.000303 1.66 1624.13 270.00 0.12 Below Prado 64445* Max WS 2698.82 117.80 123.81 123.86 0.000303 1.66 1623.75 270.00 0.12 Below Prado 64440* Max WS 2698.80 117.80 123.81 123.86 0.000304 1.66 1623.47 270.93 0.12 Below Prado 64435* Max WS 2698.43 117.80 123.81 123.85 0.000305 1.66 1623.75 272.30 0.12 HEC-RAS Plan: North_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 64430* Max WS 2698.06 117.80 123.81 123.85 0.000305 1.66 1624.58 273.66 0.12 Below Prado 64426* Max WS 2697.69 117.80 123.81 123.85 0.000306 1.66 1625.96 275.00 0.12 Below Prado 64421 Max WS 2697.31 117.80 123.81 123.85 0.000305 1.66 1627.86 276.32 0.12 Below Prado 64416 Max WS 2691.56 120.80 123.68 123.86 0.003273 3.37 797.87 284.29 0.36 Below Prado 64308* Max WS 2673.81 120.60 123.44 123.61 0.001211 3.39 788.49 284.61 0.36 Below Prado 64200 Max WS 2667.23 120.40 123.33 123.49 0.001075 3.27 816.72 285.14 0.34 Below Prado 64063* Max WS 2657.57 120.20 123.19 123.35 0.001003 3.20 829.67 282.96 0.33 Below Prado 63927 Max WS 2651.86 120.00 123.07 121.43 123.22 0.000933 3.14 843.26 279.72 0.32 Below Prado 63878 Bridge
Below Prado 63829 Max WS 2638.53 119.50 122.32 122.50 0.001225 3.41 774.63 279.24 0.36 Below Prado 63600 Max WS 2619.40 119.20 122.07 122.24 0.001109 3.28 799.59 284.29 0.34 Below Prado 63400* Max WS 2602.27 119.05 121.83 122.01 0.001216 3.36 774.24 283.96 0.36 Below Prado 63200 Max WS 2587.07 118.90 121.56 121.75 0.001402 3.50 738.84 283.50 0.38 Below Prado 63000* Max WS 2579.28 118.45 121.35 121.50 0.001043 3.20 807.09 284.52 0.33 Below Prado 62800 Max WS 2576.68 118.00 121.20 121.33 0.000747 2.88 893.45 285.79 0.29 Below Prado 62601 Max WS 2576.21 117.84 121.05 119.24 121.18 0.000745 2.89 892.48 284.66 0.29 Below Prado 62451 Bridge
Below Prado 62301 Max WS 2566.89 117.35 119.67 119.92 0.002174 4.00 642.43 281.21 0.47 Below Prado 62300 Max WS 2567.93 117.20 119.71 119.92 0.001663 3.68 698.62 283.40 0.41 Below Prado 62100* Max WS 2560.03 116.90 119.36 119.58 0.001760 3.73 685.52 283.40 0.42 Below Prado 61900 Max WS 2543.63 116.60 118.98 119.21 0.001944 3.84 662.59 283.26 0.44 Below Prado 61733* Max WS 2527.74 116.27 118.67 118.89 0.001866 3.78 668.64 283.64 0.43 Below Prado 61566* Max WS 2514.60 115.93 118.39 118.60 0.001708 3.67 685.03 284.18 0.42 Below Prado 61400 Max WS 2497.57 115.60 118.14 118.33 0.001517 3.53 707.54 284.84 0.39 Below Prado 61200* Max WS 2480.80 115.30 117.84 118.03 0.001484 3.50 709.36 284.74 0.39 Below Prado 61000 Max WS 2467.07 115.00 117.56 117.74 0.001437 3.46 713.86 284.69 0.38 Below Prado 60800* Max WS 2459.45 114.60 117.32 117.48 0.001161 3.23 760.54 285.49 0.35 Below Prado 60600 Max WS 2456.18 114.20 117.14 115.56 117.28 0.000894 2.98 823.16 286.63 0.31 Below Prado 60550 Bridge
Below Prado 60505 Max WS 2456.36 113.95 117.13 117.25 0.000697 2.77 886.27 285.71 0.28 Below Prado 60500 Max WS 2455.73 113.95 116.91 115.31 117.05 0.000884 2.98 823.83 284.73 0.31 Below Prado 60372 Bridge
Below Prado 60245 Max WS 2455.33 113.70 115.83 116.10 0.002688 4.19 585.32 279.42 0.51 Below Prado 60222* Max WS 2455.30 113.66 115.76 116.04 0.002811 4.25 577.37 279.28 0.52 Below Prado 60199* Max WS 2455.23 113.62 115.68 115.98 0.002986 4.33 566.83 279.09 0.54 Below Prado 60176* Max WS 2455.18 113.58 115.60 115.90 0.003215 4.43 554.20 278.88 0.55 Below Prado 60153 Max WS 2455.18 113.54 115.50 115.83 0.003531 4.56 538.63 278.61 0.58 Below Prado 60148* Max WS 2455.17 113.51 115.49 115.81 0.003409 4.51 544.41 278.69 0.57 Below Prado 60144* Max WS 2455.15 113.48 115.49 115.79 0.003290 4.46 550.30 278.77 0.56 Below Prado 60139* Max WS 2455.16 113.46 115.47 115.78 0.003252 4.45 552.27 278.78 0.56 Below Prado 60134* Max WS 2455.15 113.43 115.46 115.77 0.003137 4.40 558.33 278.86 0.55 Below Prado 60130 Max WS 2455.14 113.40 115.46 114.77 115.75 0.003025 4.35 564.53 278.94 0.54 Below Prado 60122 Inl Struct
Below Prado 60115 Max WS 2452.90 103.40 109.54 109.58 0.000239 1.47 1670.37 283.02 0.11 Below Prado 60110* Max WS 2452.90 103.40 109.54 109.58 0.000239 1.47 1665.28 279.93 0.11 Below Prado 60105* Max WS 2452.89 103.40 109.54 109.58 0.000238 1.48 1661.50 276.85 0.11 Below Prado 60101* Max WS 2453.00 103.40 109.54 109.57 0.000237 1.48 1658.98 273.79 0.11 Below Prado 60096* Max WS 2452.77 103.40 109.54 109.57 0.000235 1.48 1657.76 270.74 0.11 Below Prado 60092* Max WS 2452.76 103.40 109.54 109.57 0.000234 1.48 1657.42 270.00 0.11 Below Prado 60087* Max WS 2452.65 103.40 109.54 109.57 0.000234 1.48 1657.12 270.00 0.11 Below Prado 60082* Max WS 2452.75 103.40 109.54 109.57 0.000234 1.48 1656.83 270.00 0.11 Below Prado 60078* Max WS 2452.64 103.40 109.54 109.57 0.000234 1.48 1656.53 270.00 0.11 Below Prado 60073* Max WS 2452.74 103.40 109.53 109.57 0.000235 1.48 1656.26 270.00 0.11 Below Prado 60069 Max WS 2452.85 103.40 109.53 109.57 0.000235 1.48 1655.96 270.00 0.11 Below Prado 60061 Max WS 2452.13 106.93 109.37 109.58 0.004758 3.67 668.96 278.33 0.42 Below Prado 59931 Max WS 2447.04 106.80 108.84 109.10 0.002652 4.06 602.84 299.35 0.50 Below Prado 59766* Max WS 2441.13 106.40 108.48 108.70 0.002201 3.75 651.54 317.27 0.46 Below Prado 59601 Max WS 2436.96 106.00 108.22 108.39 0.001588 3.32 734.18 335.52 0.40 Below Prado 59434* Max WS 2434.38 105.83 107.95 108.12 0.001681 3.31 734.53 351.26 0.40 Below Prado 59267* Max WS 2431.84 105.67 107.63 107.81 0.001966 3.41 712.47 366.79 0.43 Below Prado 59101 Max WS 2426.22 105.50 107.16 107.39 0.003168 3.87 626.33 381.67 0.53 Below Prado 58934* Max WS 2413.63 104.99 106.67 106.89 0.002859 3.72 648.69 388.74 0.51 Below Prado 58767* Max WS 2402.12 104.47 106.31 106.48 0.002017 3.32 723.80 396.33 0.43 Below Prado 58601 Max WS 2398.37 103.96 106.10 106.22 0.001185 2.80 855.33 404.46 0.34 Below Prado 58464 Max WS 2397.05 103.63 105.90 106.05 0.001365 3.11 771.09 347.51 0.37 Below Prado 58353 Max WS 2396.90 103.44 105.77 104.59 105.91 0.001181 2.96 810.95 353.39 0.34 Below Prado 58307 Bridge
Below Prado 58260 Max WS 2396.71 103.30 105.15 105.37 0.002503 3.70 647.07 353.33 0.48 Below Prado 58252* Max WS 2396.74 103.28 105.13 105.34 0.002510 3.71 646.77 353.63 0.48 Below Prado 58243* Max WS 2396.73 103.26 105.11 105.32 0.002518 3.71 646.38 353.92 0.48 Below Prado 58234* Max WS 2396.71 103.24 105.09 105.30 0.002525 3.71 646.00 354.22 0.48 Below Prado 58225* Max WS 2396.68 103.21 105.07 105.28 0.002473 3.69 650.35 354.58 0.48 Below Prado 58216* Max WS 2396.69 103.19 105.04 105.26 0.002478 3.69 650.13 354.88 0.48 Below Prado 58207 Max WS 2396.67 103.17 105.02 105.23 0.002484 3.69 649.90 355.18 0.48 Below Prado 58198 Max WS 2396.67 103.15 104.95 104.35 105.21 0.003191 4.09 586.59 331.91 0.54 Below Prado 58188 Inl Struct
Below Prado 58178 Max WS 2352.02 93.15 100.55 100.57 0.000027 0.95 2482.11 350.47 0.06 Below Prado 58174* Max WS 2352.51 93.15 100.55 100.57 0.000027 0.94 2493.33 351.94 0.06 Below Prado 58169* Max WS 2352.03 93.15 100.55 100.57 0.000027 0.94 2504.65 353.43 0.06 HEC-RAS Plan: North_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 58164* Max WS 2352.97 93.15 100.55 100.57 0.000027 0.94 2515.87 354.90 0.06 Below Prado 58159* Max WS 2352.50 93.15 100.55 100.57 0.000026 0.93 2527.16 356.38 0.06 Below Prado 58154* Max WS 2352.95 93.15 100.55 100.57 0.000026 0.93 2538.38 357.85 0.06 Below Prado 58149* Max WS 2352.94 93.15 100.55 100.57 0.000026 0.92 2549.68 359.33 0.06 Below Prado 58144* Max WS 2352.94 93.15 100.55 100.57 0.000026 0.92 2560.89 360.80 0.06 Below Prado 58139* Max WS 2352.49 93.15 100.55 100.57 0.000025 0.91 2572.14 362.28 0.06 Below Prado 58134* Max WS 2353.37 93.15 100.55 100.57 0.000025 0.91 2583.35 363.75 0.06 Below Prado 58130* Max WS 2352.48 93.15 100.55 100.57 0.000025 0.91 2594.64 365.22 0.06 Below Prado 58125* Max WS 2353.33 93.15 100.55 100.57 0.000025 0.90 2605.88 366.69 0.06 Below Prado 58120* Max WS 2352.90 93.15 100.55 100.57 0.000024 0.90 2617.08 368.16 0.06 Below Prado 58115* Max WS 2352.46 93.15 100.55 100.57 0.000024 0.90 2628.32 369.63 0.06 Below Prado 58110* Max WS 2352.87 93.15 100.55 100.57 0.000024 0.89 2639.56 371.10 0.06 Below Prado 58105* Max WS 2352.86 93.15 100.55 100.57 0.000024 0.89 2650.79 372.58 0.06 Below Prado 58100 Max WS 2353.25 93.15 100.55 100.57 0.000024 0.88 2661.98 374.04 0.06 Below Prado 58094 Max WS 2350.42 97.40 100.51 100.57 0.000373 2.01 1168.94 381.70 0.20 Below Prado 57997* Max WS 2348.14 97.20 100.43 100.53 0.000573 2.50 939.89 306.71 0.25 Below Prado 57900 Max WS 2344.46 97.00 100.27 100.45 0.001165 3.39 691.55 243.19 0.35 Below Prado 57800* Max WS 2342.29 96.83 100.13 100.33 0.001265 3.55 659.24 229.77 0.37 Below Prado 57700* Max WS 2340.48 96.67 99.97 100.19 0.001421 3.77 621.07 216.15 0.39 Below Prado 57600 Max WS 2339.20 96.50 99.79 100.04 0.001635 4.03 580.58 203.08 0.42 Below Prado 57550* Max WS 2338.45 96.38 99.68 99.96 0.001803 4.21 555.49 195.70 0.44 Below Prado 57500* Max WS 2338.06 96.25 99.56 99.86 0.001962 4.41 530.22 185.50 0.46 Below Prado 57450* Max WS 2337.81 96.12 99.43 99.76 0.002058 4.62 505.82 170.71 0.47 Below Prado 57400 Max WS 2337.39 96.00 99.29 99.65 0.002284 4.86 481.22 162.86 0.50 Below Prado 57375* Max WS 2337.12 95.94 99.21 99.59 0.002394 4.98 469.55 158.69 0.51 Below Prado 57350* Max WS 2336.95 95.88 99.13 99.53 0.002496 5.09 459.48 155.11 0.52 Below Prado 57325* Max WS 2336.86 95.81 99.06 99.47 0.002621 5.16 452.87 155.19 0.53 Below Prado 57300* Max WS 2336.71 95.75 98.98 99.40 0.002761 5.24 446.07 155.44 0.55 Below Prado 57275* Max WS 2336.63 95.69 98.89 99.33 0.002871 5.31 439.91 154.65 0.56 Below Prado 57250* Max WS 2336.50 95.62 98.81 99.26 0.002928 5.36 435.99 153.47 0.56 Below Prado 57225* Max WS 2336.43 95.56 98.73 99.19 0.003021 5.43 430.34 152.07 0.57 Below Prado 57200 Max WS 2336.37 95.50 98.64 99.11 0.003114 5.50 424.79 150.59 0.58 Below Prado 57175* Max WS 2336.31 95.45 98.54 99.03 0.003272 5.59 418.02 150.15 0.59 Below Prado 57150* Max WS 2336.26 95.40 98.44 98.95 0.003473 5.70 410.03 149.63 0.61 Below Prado 57125* Max WS 2336.24 95.35 98.33 98.86 0.003737 5.83 400.44 149.01 0.63 Below Prado 57100* Max WS 2336.18 95.30 98.20 98.76 0.004107 6.02 388.38 148.22 0.66 Below Prado 57075 Max WS 2336.17 95.25 98.04 98.65 0.004689 6.28 372.14 147.15 0.70 Below Prado 57067* Max WS 2336.16 95.24 98.07 98.61 0.004113 5.93 394.05 153.92 0.65 Below Prado 57059* Max WS 2336.16 95.24 98.08 98.58 0.003713 5.65 413.44 160.84 0.62 Below Prado 57050 Max WS 2336.15 95.23 98.10 97.28 98.55 0.003314 5.37 435.39 168.12 0.59 Below Prado 57040 Inl Struct
Below Prado 57030 Max WS 2312.55 85.25 91.57 91.58 0.000038 1.01 2281.14 372.08 0.07 Below Prado 57020* Max WS 2313.62 85.25 91.57 91.58 0.000038 1.01 2281.02 372.08 0.07 Below Prado 57010* Max WS 2313.26 85.25 91.57 91.58 0.000038 1.01 2280.90 372.08 0.07 Below Prado 57000* Max WS 2312.54 85.24 91.57 91.58 0.000038 1.01 2284.49 372.11 0.07 Below Prado 56990* Max WS 2313.21 85.24 91.57 91.58 0.000038 1.01 2284.37 372.11 0.07 Below Prado 56980* Max WS 2312.53 85.24 91.57 91.58 0.000038 1.01 2284.24 372.10 0.07 Below Prado 56970* Max WS 2312.85 85.24 91.57 91.58 0.000038 1.01 2284.12 372.10 0.07 Below Prado 56960* Max WS 2312.83 85.23 91.57 91.58 0.000037 1.01 2287.70 372.13 0.07 Below Prado 56950 Max WS 2312.50 85.23 91.57 91.58 0.000037 1.01 2287.58 372.13 0.07 Below Prado 56947 Max WS 2306.80 89.44 91.46 91.62 0.001700 3.23 714.35 358.42 0.40 Below Prado 56868* Max WS 2298.30 89.33 91.34 91.49 0.001612 3.13 733.18 369.46 0.39 Below Prado 56789* Max WS 2290.49 89.22 91.22 91.37 0.001512 3.03 754.73 380.52 0.38 Below Prado 56710* Max WS 2283.57 89.11 91.12 91.25 0.001403 2.93 779.53 391.61 0.37 Below Prado 56630 Max WS 2279.44 89.00 91.02 91.14 0.001287 2.82 808.07 402.72 0.35 Below Prado 56537* Max WS 2273.80 88.73 90.90 91.03 0.001247 2.90 783.21 365.13 0.35 Below Prado 56444* Max WS 2269.78 88.47 90.76 90.91 0.001290 3.06 741.71 327.62 0.36 Below Prado 56350 Max WS 2264.91 88.20 90.62 90.79 0.001397 3.29 689.16 290.23 0.38 Below Prado 56258* Max WS 2260.69 88.07 90.49 90.66 0.001416 3.31 683.50 288.12 0.38 Below Prado 56165* Max WS 2256.60 87.94 90.35 90.52 0.001442 3.33 677.09 285.99 0.38 Below Prado 56072* Max WS 2252.68 87.81 90.21 90.39 0.001475 3.36 669.78 283.86 0.39 Below Prado 55979* Max WS 2248.67 87.69 90.07 90.25 0.001547 3.42 657.51 281.66 0.39 Below Prado 55886* Max WS 2245.19 87.56 89.92 90.10 0.001616 3.47 646.38 279.47 0.40 Below Prado 55793* Max WS 2240.41 87.43 89.75 89.95 0.001709 3.54 632.68 277.23 0.41 Below Prado 55700 Max WS 2236.31 87.30 89.58 89.78 0.001847 3.63 615.38 274.93 0.43 Below Prado 55608* Max WS 2231.66 87.13 89.41 89.62 0.001816 3.61 618.60 275.78 0.42 Below Prado 55515* Max WS 2227.18 86.95 89.26 89.45 0.001738 3.55 626.82 276.70 0.42 Below Prado 55423* Max WS 2222.67 86.78 89.10 89.29 0.001676 3.51 633.82 277.60 0.41 Below Prado 55330 Max WS 2217.58 86.60 88.96 89.14 0.001567 3.43 646.78 278.59 0.40 Below Prado 55240* Max WS 2213.11 86.48 88.82 89.00 0.001573 3.42 647.73 281.27 0.40 Below Prado 55150* Max WS 2206.61 86.37 88.68 88.86 0.001610 3.42 644.47 283.88 0.40 Below Prado 55060* Max WS 2199.22 86.25 88.53 88.72 0.001625 3.42 643.67 286.53 0.40 Below Prado 54970* Max WS 2191.03 86.13 88.39 88.57 0.001645 3.41 642.23 289.18 0.40 Below Prado 54880* Max WS 2180.05 86.02 88.24 88.42 0.001702 3.43 636.03 291.75 0.41 Below Prado 54790 Max WS 2165.82 85.90 88.08 88.26 0.001739 3.43 631.71 294.36 0.41 Below Prado 54692.5* Max WS 2150.45 85.70 87.92 88.10 0.001624 3.36 640.66 292.79 0.40 Below Prado 54595.0* Max WS 2136.58 85.50 87.78 87.95 0.001491 3.27 653.44 291.29 0.38 Below Prado 54497.5* Max WS 2125.18 85.30 87.65 87.81 0.001346 3.17 670.34 289.84 0.37 Below Prado 54400 Max WS 2116.83 85.10 87.54 87.69 0.001197 3.06 691.46 288.46 0.35 HEC-RAS Plan: North_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 54300.0* Max WS 2108.22 84.95 87.43 87.57 0.001145 3.02 697.27 286.60 0.34 Below Prado 54200.0* Max WS 2102.64 84.80 87.32 87.46 0.001091 2.98 704.49 284.76 0.33 Below Prado 54100.0* Max WS 2098.13 84.65 87.22 87.35 0.001034 2.94 713.18 282.94 0.33 Below Prado 54000 Max WS 2095.20 84.50 87.12 87.26 0.000975 2.90 723.38 281.15 0.32 Below Prado 53912* Max WS 2092.65 84.36 87.04 87.17 0.000969 2.92 715.93 273.10 0.32 Below Prado 53823* Max WS 2091.30 84.21 86.95 87.09 0.000953 2.94 710.70 265.09 0.32 Below Prado 53735* Max WS 2089.86 84.07 86.86 87.00 0.000954 2.98 701.55 257.04 0.32 Below Prado 53646* Max WS 2089.53 83.93 86.78 86.92 0.000961 3.02 691.30 248.99 0.32 Below Prado 53558* Max WS 2089.08 83.79 86.69 86.83 0.000972 3.07 679.80 240.92 0.32 Below Prado 53469* Max WS 2089.06 83.64 86.60 86.75 0.000977 3.12 669.70 232.90 0.32 Below Prado 53380 Max WS 2088.95 83.50 86.50 84.93 86.66 0.001001 3.19 655.56 224.82 0.33 Appendix D
South Deflation HEC-RAS Model Output

HEC-RAS Plan: South_Short River: Santa Ana River Reach: Below Prado Profile: Max WS Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 69601 Max WS 2068.25 144.20 146.50 146.67 0.001472 3.26 634.16 281.08 0.38 Below Prado 69366 Max WS 2066.84 143.83 146.17 145.05 146.33 0.001399 3.22 641.46 278.43 0.37 Below Prado 69341 Bridge
Below Prado 69313 Max WS 2066.15 143.66 145.70 145.92 0.002194 3.69 559.23 277.16 0.46 Below Prado 69200 Max WS 2065.03 143.44 145.44 145.66 0.002357 3.77 547.13 277.57 0.47 Below Prado 69176* Max WS 2064.97 143.39 145.38 145.60 0.002393 3.79 544.96 277.64 0.48 Below Prado 69152* Max WS 2064.90 143.34 145.32 145.55 0.002430 3.81 542.46 277.72 0.48 Below Prado 69128* Max WS 2064.78 143.29 145.26 145.49 0.002473 3.83 539.63 277.80 0.48 Below Prado 69104* Max WS 2064.75 143.24 145.20 145.43 0.002524 3.85 536.38 277.88 0.49 Below Prado 69080* Max WS 2064.72 143.20 145.13 145.37 0.002649 3.91 528.70 277.93 0.50 Below Prado 69056* Max WS 2064.68 143.15 145.06 145.30 0.002735 3.94 523.71 278.01 0.51 Below Prado 69032* Max WS 2064.83 143.10 144.99 145.24 0.002841 3.99 517.79 278.10 0.52 Below Prado 69009 Max WS 2064.78 143.05 144.91 145.17 0.002975 4.04 510.74 278.18 0.53 Below Prado 69004* Max WS 2064.79 143.04 144.90 145.15 0.003006 4.06 509.15 278.20 0.53 Below Prado 68999* Max WS 2064.78 143.03 144.88 145.14 0.003039 4.07 507.51 278.22 0.53 Below Prado 68994* Max WS 2064.78 143.02 144.87 145.12 0.003074 4.08 505.77 278.23 0.53 Below Prado 68989* Max WS 2064.77 143.01 144.85 145.11 0.003110 4.10 504.01 278.25 0.54 Below Prado 68985 Max WS 2064.77 143.00 144.83 144.22 145.09 0.003149 4.11 502.13 278.27 0.54 Below Prado 68977 Inl Struct
Below Prado 68969 Max WS 2060.87 132.80 138.13 138.16 0.000244 1.38 1491.70 280.00 0.11 Below Prado 68964* Max WS 2061.21 132.80 138.13 138.16 0.000246 1.39 1485.98 279.00 0.11 Below Prado 68959* Max WS 2061.57 132.80 138.12 138.15 0.000248 1.39 1480.29 278.00 0.11 Below Prado 68955* Max WS 2061.45 132.80 138.12 138.15 0.000250 1.40 1474.58 277.00 0.11 Below Prado 68950* Max WS 2061.33 132.80 138.12 138.15 0.000252 1.40 1468.87 276.00 0.11 Below Prado 68945* Max WS 2061.32 132.80 138.12 138.15 0.000255 1.41 1463.14 275.00 0.11 Below Prado 68940* Max WS 2061.31 132.80 138.12 138.15 0.000257 1.41 1457.43 274.00 0.11 Below Prado 68936* Max WS 2061.42 132.80 138.12 138.15 0.000259 1.42 1451.76 273.42 0.11 Below Prado 68931* Max WS 2061.31 132.80 138.12 138.15 0.000262 1.43 1446.50 273.80 0.11 Below Prado 68926* Max WS 2061.41 132.80 138.11 138.15 0.000264 1.43 1441.86 274.14 0.11 Below Prado 68922 Max WS 2061.41 132.80 138.11 138.15 0.000267 1.43 1437.76 274.44 0.11 Below Prado 68916 Max WS 2060.13 135.73 137.98 138.16 0.003945 3.17 621.76 282.77 0.38 Below Prado 68808* Max WS 2056.16 135.51 137.66 137.85 0.001830 3.48 591.38 280.42 0.42 Below Prado 68700 Max WS 2054.32 135.30 137.47 137.65 0.001777 3.45 595.25 279.18 0.42 Below Prado 68547* Max WS 2053.63 134.95 137.24 137.41 0.001477 3.26 629.68 279.82 0.38 Below Prado 68395 Max WS 2053.64 134.60 137.06 135.81 137.21 0.001159 3.03 678.22 280.77 0.34 Below Prado 68222 Bridge
Below Prado 68050 Max WS 2049.38 134.10 136.18 136.38 0.002024 3.58 571.87 279.48 0.44 Below Prado 67866* Max WS 2044.77 133.73 135.81 136.01 0.002013 3.58 571.52 278.82 0.44 Below Prado 67683* Max WS 2039.99 133.37 135.44 135.64 0.002055 3.60 566.67 278.13 0.44 Below Prado 67500 Max WS 2036.29 133.00 135.06 135.26 0.002088 3.62 562.84 277.48 0.45 Below Prado 67333* Max WS 2033.33 132.62 134.74 134.93 0.001869 3.48 584.04 280.88 0.43 Below Prado 67166* Max WS 2031.62 132.24 134.48 134.65 0.001561 3.28 619.93 285.38 0.39 Below Prado 67000 Max WS 2030.89 131.86 134.27 134.41 0.001261 3.00 675.88 301.98 0.35 Below Prado 66922 Max WS 2030.63 131.80 134.16 133.00 134.31 0.001302 3.12 651.38 281.80 0.36 Below Prado 66884 Bridge
Below Prado 66847 Max WS 2028.52 131.60 133.59 133.80 0.002301 3.71 546.49 279.05 0.47 Below Prado 66723* Max WS 2026.11 131.30 133.32 133.53 0.002186 3.66 554.25 278.52 0.46 Below Prado 66600 Max WS 2024.10 131.00 133.07 133.27 0.002002 3.56 568.74 278.55 0.44 Below Prado 66433* Max WS 2021.07 130.67 132.74 132.94 0.002012 3.56 567.24 278.38 0.44 Below Prado 66266* Max WS 2018.64 130.33 132.41 132.60 0.001974 3.54 570.03 278.27 0.44 Below Prado 66100 Max WS 2015.82 130.00 132.08 132.28 0.001956 3.53 571.08 278.14 0.43 Below Prado 65933* Max WS 2013.14 129.67 131.76 131.96 0.001917 3.51 574.22 278.36 0.43 Below Prado 65766* Max WS 2010.80 129.33 131.46 131.65 0.001798 3.44 585.25 278.71 0.42 Below Prado 65600 Max WS 2009.13 129.00 131.19 131.36 0.001653 3.35 600.26 279.13 0.40 Below Prado 65425* Max WS 2007.92 128.73 130.89 131.07 0.001725 3.39 592.44 279.19 0.41 Below Prado 65250* Max WS 2007.16 128.45 130.57 130.76 0.001819 3.44 582.99 279.21 0.42 Below Prado 65075* Max WS 2006.35 128.18 130.22 130.42 0.002089 3.59 558.85 279.00 0.45 Below Prado 64900 Max WS 2005.38 127.90 129.71 129.96 0.003106 4.05 495.38 278.13 0.53 Below Prado 64734* Max WS 2004.89 127.34 129.25 129.48 0.002719 3.89 515.15 277.63 0.50 Below Prado 64568 Max WS 2004.64 126.78 128.85 129.07 0.002304 3.70 541.37 277.59 0.47 Below Prado 64559* Max WS 2004.64 126.78 128.83 129.05 0.002323 3.71 540.00 277.52 0.47 Below Prado 64550* Max WS 2004.64 126.78 128.81 129.02 0.002335 3.72 539.15 277.48 0.47 Below Prado 64541* Max WS 2004.61 126.79 128.78 129.00 0.002415 3.76 533.62 277.39 0.48 Below Prado 64532* Max WS 2004.61 126.79 128.76 128.98 0.002462 3.78 530.52 277.34 0.48 Below Prado 64522* Max WS 2004.57 126.79 128.73 128.96 0.002538 3.81 525.61 277.25 0.49 Below Prado 64513* Max WS 2004.59 126.79 128.70 128.93 0.002626 3.85 520.23 277.19 0.50 Below Prado 64504* Max WS 2004.59 126.80 128.67 128.91 0.002810 3.93 509.67 277.07 0.51 Below Prado 64495 Max WS 2004.59 126.80 128.63 128.88 0.002973 4.00 501.06 276.98 0.52 Below Prado 64490* Max WS 2004.58 126.80 128.61 128.87 0.003074 4.04 495.99 276.91 0.53 Below Prado 64486 Max WS 2004.58 126.80 128.59 127.99 128.85 0.003189 4.09 490.53 276.86 0.54 Below Prado 64478 Inl Struct
Below Prado 64470 Max WS 1993.24 117.80 123.33 123.36 0.000217 1.33 1493.59 270.00 0.10 Below Prado 64465* Max WS 1992.85 117.80 123.33 123.36 0.000218 1.33 1493.32 270.00 0.10 Below Prado 64460* Max WS 1992.95 117.80 123.33 123.36 0.000218 1.33 1493.02 270.00 0.10 Below Prado 64455* Max WS 1993.14 117.80 123.33 123.36 0.000218 1.34 1492.75 270.00 0.10 Below Prado 64450* Max WS 1992.95 117.80 123.33 123.36 0.000218 1.34 1492.45 270.00 0.10 Below Prado 64445* Max WS 1992.94 117.80 123.33 123.35 0.000218 1.34 1492.15 270.00 0.10 Below Prado 64440* Max WS 1992.85 117.80 123.33 123.35 0.000218 1.34 1491.86 270.00 0.10 Below Prado 64435* Max WS 1992.94 117.80 123.32 123.35 0.000219 1.34 1491.65 270.66 0.10 HEC-RAS Plan: South_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 64430* Max WS 1992.85 117.80 123.32 123.35 0.000219 1.34 1491.90 272.03 0.10 Below Prado 64426* Max WS 1992.84 117.80 123.32 123.35 0.000220 1.34 1492.73 273.38 0.10 Below Prado 64421 Max WS 1992.75 117.80 123.32 123.35 0.000220 1.33 1494.10 274.71 0.10 Below Prado 64416 Max WS 1989.18 120.80 123.22 123.36 0.003203 2.98 667.45 282.00 0.34 Below Prado 64308* Max WS 1984.69 120.60 122.98 123.12 0.001202 3.01 658.76 282.50 0.35 Below Prado 64200 Max WS 1981.37 120.40 122.87 123.00 0.001048 2.89 686.59 283.24 0.33 Below Prado 64063* Max WS 1979.38 120.20 122.74 122.86 0.000966 2.82 701.26 281.22 0.32 Below Prado 63927 Max WS 1977.06 120.00 122.62 121.19 122.74 0.000881 2.75 717.63 278.29 0.30 Below Prado 63878 Bridge
Below Prado 63829 Max WS 1974.41 119.50 121.89 122.03 0.001194 3.02 654.27 277.83 0.35 Below Prado 63600 Max WS 1970.49 119.20 121.64 121.77 0.001080 2.91 677.69 282.59 0.33 Below Prado 63400* Max WS 1967.89 119.05 121.40 121.54 0.001218 3.02 652.67 282.27 0.35 Below Prado 63200 Max WS 1964.38 118.90 121.11 121.27 0.001484 3.20 614.03 281.75 0.38 Below Prado 63000* Max WS 1962.41 118.45 120.89 121.02 0.001073 2.90 677.34 282.70 0.33 Below Prado 62800 Max WS 1961.77 118.00 120.74 120.84 0.000729 2.58 761.81 283.94 0.28 Below Prado 62601 Max WS 1960.92 117.84 120.59 119.01 120.69 0.000723 2.57 762.46 282.76 0.28 Below Prado 62451 Bridge
Below Prado 62301 Max WS 1959.00 117.35 119.32 119.52 0.002206 3.61 542.56 279.72 0.46 Below Prado 62300 Max WS 1959.06 117.20 119.35 119.52 0.001621 3.28 597.09 281.91 0.40 Below Prado 62100* Max WS 1956.13 116.90 119.01 119.19 0.001714 3.33 586.58 281.93 0.41 Below Prado 61900 Max WS 1952.28 116.60 118.64 118.82 0.001930 3.45 565.26 281.78 0.43 Below Prado 61733* Max WS 1948.18 116.27 118.33 118.51 0.001865 3.41 570.68 282.11 0.42 Below Prado 61566* Max WS 1943.63 115.93 118.04 118.21 0.001703 3.32 585.95 282.59 0.41 Below Prado 61400 Max WS 1939.50 115.60 117.79 117.94 0.001506 3.19 607.81 283.20 0.38 Below Prado 61200* Max WS 1936.43 115.30 117.49 117.65 0.001490 3.18 609.18 283.18 0.38 Below Prado 61000 Max WS 1933.65 115.00 117.20 117.35 0.001464 3.16 611.93 283.19 0.38 Below Prado 60800* Max WS 1932.20 114.60 116.96 117.09 0.001160 2.94 656.57 283.88 0.34 Below Prado 60600 Max WS 1931.40 114.20 116.78 115.35 116.89 0.000861 2.69 718.85 284.94 0.30 Below Prado 60550 Bridge
Below Prado 60505 Max WS 1931.37 113.95 116.77 116.86 0.000644 2.47 783.50 284.10 0.26 Below Prado 60500 Max WS 1931.27 113.95 116.57 115.11 116.68 0.000826 2.66 726.06 283.19 0.29 Below Prado 60372 Bridge
Below Prado 60245 Max WS 1931.22 113.70 115.54 115.77 0.002700 3.82 505.09 278.14 0.50 Below Prado 60222* Max WS 1931.18 113.66 115.47 115.71 0.002846 3.89 497.04 278.00 0.51 Below Prado 60199* Max WS 1931.15 113.62 115.40 115.64 0.003060 3.97 486.22 277.82 0.53 Below Prado 60176* Max WS 1931.15 113.58 115.31 115.57 0.003355 4.08 472.82 277.59 0.55 Below Prado 60153 Max WS 1931.14 113.54 115.20 115.48 0.003795 4.24 455.44 277.30 0.58 Below Prado 60148* Max WS 1931.13 113.51 115.19 115.47 0.003652 4.19 460.78 277.37 0.57 Below Prado 60144* Max WS 1931.13 113.48 115.18 115.45 0.003512 4.14 466.26 277.44 0.56 Below Prado 60139* Max WS 1931.13 113.46 115.17 115.43 0.003473 4.13 467.83 277.46 0.56 Below Prado 60134* Max WS 1931.13 113.43 115.16 115.42 0.003337 4.08 473.56 277.53 0.55 Below Prado 60130 Max WS 1931.13 113.40 115.15 114.57 115.40 0.003204 4.03 479.41 277.61 0.54 Below Prado 60122 Inl Struct
Below Prado 60115 Max WS 1930.69 103.40 109.22 109.25 0.000176 1.22 1579.63 280.62 0.09 Below Prado 60110* Max WS 1930.75 103.40 109.22 109.24 0.000176 1.23 1575.64 277.54 0.09 Below Prado 60105* Max WS 1930.62 103.40 109.22 109.24 0.000175 1.23 1572.93 274.47 0.09 Below Prado 60101* Max WS 1930.71 103.40 109.22 109.24 0.000174 1.23 1571.51 271.41 0.09 Below Prado 60096* Max WS 1930.66 103.40 109.22 109.24 0.000173 1.23 1571.16 270.00 0.09 Below Prado 60092* Max WS 1930.71 103.40 109.22 109.24 0.000173 1.23 1570.94 270.00 0.09 Below Prado 60087* Max WS 1930.70 103.40 109.22 109.24 0.000173 1.23 1570.72 270.00 0.09 Below Prado 60082* Max WS 1930.70 103.40 109.22 109.24 0.000173 1.23 1570.51 270.00 0.09 Below Prado 60078* Max WS 1930.59 103.40 109.22 109.24 0.000173 1.23 1570.29 270.00 0.09 Below Prado 60073* Max WS 1930.62 103.40 109.22 109.24 0.000173 1.23 1570.08 270.00 0.09 Below Prado 60069 Max WS 1930.62 103.40 109.21 109.24 0.000173 1.23 1569.86 270.00 0.09 Below Prado 60061 Max WS 1930.54 106.93 109.08 109.25 0.004486 3.28 588.89 277.35 0.40 Below Prado 59931 Max WS 1929.15 106.80 108.58 108.79 0.002619 3.68 523.83 298.27 0.49 Below Prado 59766* Max WS 1927.28 106.40 108.22 108.40 0.002161 3.40 567.67 316.22 0.45 Below Prado 59601 Max WS 1926.12 106.00 107.96 108.09 0.001507 2.98 646.74 334.52 0.38 Below Prado 59434* Max WS 1925.19 105.83 107.70 107.84 0.001590 2.97 647.92 350.30 0.39 Below Prado 59267* Max WS 1924.45 105.67 107.40 107.55 0.001862 3.06 628.62 365.88 0.41 Below Prado 59101 Max WS 1923.25 105.50 106.94 107.13 0.003182 3.54 543.57 380.79 0.52 Below Prado 58934* Max WS 1920.52 104.99 106.44 106.62 0.002989 3.44 557.49 387.80 0.51 Below Prado 58767* Max WS 1916.78 104.47 106.05 106.20 0.002165 3.10 618.12 395.27 0.44 Below Prado 58601 Max WS 1914.83 103.96 105.81 105.91 0.001222 2.59 739.33 403.32 0.34 Below Prado 58464 Max WS 1914.28 103.63 105.61 105.74 0.001360 2.84 672.96 345.70 0.36 Below Prado 58353 Max WS 1914.17 103.44 105.49 104.43 105.60 0.001161 2.69 711.13 352.09 0.33 Below Prado 58307 Bridge
Below Prado 58260 Max WS 1914.10 103.30 104.90 105.09 0.002584 3.42 559.27 352.21 0.48 Below Prado 58252* Max WS 1914.08 103.28 104.88 105.06 0.002598 3.43 558.54 352.50 0.48 Below Prado 58243* Max WS 1914.10 103.26 104.86 105.04 0.002614 3.43 557.69 352.77 0.48 Below Prado 58234* Max WS 1914.07 103.24 104.83 105.02 0.002630 3.44 556.81 353.06 0.48 Below Prado 58225* Max WS 1914.08 103.21 104.81 104.99 0.002575 3.41 560.61 353.40 0.48 Below Prado 58216* Max WS 1914.07 103.19 104.79 104.97 0.002588 3.42 559.90 353.68 0.48 Below Prado 58207 Max WS 1914.06 103.17 104.77 104.95 0.002604 3.42 559.09 353.97 0.48 Below Prado 58198 Max WS 1914.05 103.15 104.70 104.18 104.92 0.003372 3.80 503.09 330.24 0.54 Below Prado 58188 Inl Struct
Below Prado 58178 Max WS 1899.38 93.15 100.14 100.15 0.000022 0.81 2338.28 348.78 0.06 Below Prado 58174* Max WS 1899.18 93.15 100.14 100.15 0.000021 0.81 2348.89 350.25 0.06 Below Prado 58169* Max WS 1898.77 93.15 100.14 100.15 0.000021 0.80 2359.60 351.74 0.05 HEC-RAS Plan: South_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 58164* Max WS 1898.97 93.15 100.14 100.15 0.000021 0.80 2370.21 353.22 0.05 Below Prado 58159* Max WS 1898.97 93.15 100.14 100.15 0.000021 0.80 2380.86 354.71 0.05 Below Prado 58154* Max WS 1899.36 93.15 100.14 100.15 0.000021 0.79 2391.47 356.18 0.05 Below Prado 58149* Max WS 1899.35 93.15 100.14 100.15 0.000020 0.79 2402.16 357.67 0.05 Below Prado 58144* Max WS 1899.15 93.15 100.14 100.15 0.000020 0.79 2412.76 359.14 0.05 Below Prado 58139* Max WS 1899.15 93.15 100.14 100.15 0.000020 0.78 2423.41 360.62 0.05 Below Prado 58134* Max WS 1899.32 93.15 100.14 100.15 0.000020 0.78 2434.01 362.10 0.05 Below Prado 58130* Max WS 1899.14 93.15 100.14 100.15 0.000020 0.78 2444.65 363.57 0.05 Below Prado 58125* Max WS 1898.96 93.15 100.14 100.15 0.000019 0.77 2455.29 365.05 0.05 Below Prado 58120* Max WS 1899.13 93.15 100.14 100.15 0.000019 0.77 2465.88 366.52 0.05 Below Prado 58115* Max WS 1898.78 93.15 100.14 100.15 0.000019 0.77 2476.51 368.00 0.05 Below Prado 58110* Max WS 1899.11 93.15 100.14 100.15 0.000019 0.76 2487.15 369.48 0.05 Below Prado 58105* Max WS 1898.95 93.15 100.14 100.15 0.000019 0.76 2497.78 370.96 0.05 Below Prado 58100 Max WS 1899.11 93.15 100.14 100.15 0.000019 0.76 2508.36 372.42 0.05 Below Prado 58094 Max WS 1898.29 97.40 100.10 100.16 0.000388 1.87 1014.32 380.18 0.20 Below Prado 57997* Max WS 1897.19 97.20 100.03 100.11 0.000586 2.32 817.06 302.75 0.25 Below Prado 57900 Max WS 1895.57 97.00 99.87 100.03 0.001194 3.18 596.50 235.51 0.35 Below Prado 57800* Max WS 1894.38 96.83 99.73 99.90 0.001290 3.33 569.39 222.34 0.37 Below Prado 57700* Max WS 1893.55 96.67 99.57 99.77 0.001452 3.53 536.45 209.39 0.39 Below Prado 57600 Max WS 1892.88 96.50 99.39 99.61 0.001676 3.78 501.03 196.66 0.42 Below Prado 57550* Max WS 1892.62 96.38 99.28 99.53 0.001828 3.95 479.39 187.92 0.44 Below Prado 57500* Max WS 1892.44 96.25 99.17 99.43 0.001948 4.12 459.21 176.86 0.45 Below Prado 57450* Max WS 1892.11 96.12 99.05 99.33 0.002058 4.29 441.08 166.56 0.46 Below Prado 57400 Max WS 1892.06 96.00 98.91 99.22 0.002274 4.50 420.42 159.09 0.49 Below Prado 57375* Max WS 1891.91 95.94 98.84 99.17 0.002370 4.60 410.99 155.07 0.50 Below Prado 57350* Max WS 1891.87 95.88 98.76 99.11 0.002468 4.70 402.77 151.98 0.51 Below Prado 57325* Max WS 1891.83 95.81 98.69 99.04 0.002529 4.76 397.39 149.65 0.52 Below Prado 57300* Max WS 1891.70 95.75 98.61 98.98 0.002654 4.84 390.96 149.03 0.53 Below Prado 57275* Max WS 1891.72 95.69 98.54 98.91 0.002792 4.91 385.42 149.42 0.54 Below Prado 57250* Max WS 1891.66 95.62 98.46 98.84 0.002858 4.95 382.32 149.04 0.54 Below Prado 57225* Max WS 1891.61 95.56 98.38 98.77 0.002956 5.01 377.63 148.22 0.55 Below Prado 57200 Max WS 1891.52 95.50 98.29 98.69 0.003049 5.07 373.13 147.21 0.56 Below Prado 57175* Max WS 1891.55 95.45 98.20 98.61 0.003209 5.15 367.05 146.81 0.57 Below Prado 57150* Max WS 1891.48 95.40 98.10 98.53 0.003413 5.26 359.84 146.33 0.59 Below Prado 57125* Max WS 1891.46 95.35 97.99 98.44 0.003686 5.39 351.04 145.74 0.61 Below Prado 57100* Max WS 1891.45 95.30 97.86 98.35 0.004080 5.57 339.78 144.99 0.64 Below Prado 57075 Max WS 1891.45 95.25 97.71 98.24 0.004712 5.83 324.47 143.96 0.68 Below Prado 57067* Max WS 1891.45 95.24 97.72 98.20 0.004182 5.53 342.20 150.43 0.65 Below Prado 57059* Max WS 1891.44 95.24 97.73 98.17 0.003823 5.29 357.57 157.03 0.62 Below Prado 57050 Max WS 1891.44 95.23 97.74 97.01 98.14 0.003440 5.04 375.47 163.96 0.59 Below Prado 57040 Inl Struct
Below Prado 57030 Max WS 1883.31 85.25 91.31 91.33 0.000029 0.86 2186.89 371.20 0.06 Below Prado 57020* Max WS 1883.29 85.25 91.31 91.33 0.000029 0.86 2186.79 371.20 0.06 Below Prado 57010* Max WS 1883.00 85.25 91.31 91.33 0.000029 0.86 2186.69 371.19 0.06 Below Prado 57000* Max WS 1883.14 85.24 91.31 91.33 0.000029 0.86 2190.30 371.22 0.06 Below Prado 56990* Max WS 1883.13 85.24 91.31 91.33 0.000029 0.86 2190.20 371.22 0.06 Below Prado 56980* Max WS 1883.11 85.24 91.31 91.32 0.000029 0.86 2190.10 371.22 0.06 Below Prado 56970* Max WS 1882.97 85.24 91.31 91.32 0.000029 0.86 2190.00 371.22 0.06 Below Prado 56960* Max WS 1882.70 85.23 91.31 91.32 0.000028 0.86 2193.61 371.24 0.06 Below Prado 56950 Max WS 1882.69 85.23 91.31 91.32 0.000028 0.86 2193.50 371.24 0.06 Below Prado 56947 Max WS 1880.90 89.44 91.22 91.36 0.001709 2.98 630.26 357.44 0.40 Below Prado 56868* Max WS 1877.22 89.33 91.10 91.23 0.001643 2.91 644.91 368.54 0.39 Below Prado 56789* Max WS 1873.90 89.22 90.98 91.10 0.001565 2.83 661.53 379.66 0.38 Below Prado 56710* Max WS 1870.70 89.11 90.86 90.98 0.001474 2.75 680.71 390.81 0.37 Below Prado 56630 Max WS 1868.07 89.00 90.76 90.87 0.001371 2.66 703.06 401.98 0.35 Below Prado 56537* Max WS 1865.36 88.73 90.63 90.75 0.001297 2.72 686.58 364.26 0.35 Below Prado 56444* Max WS 1862.98 88.47 90.50 90.62 0.001309 2.84 655.08 326.63 0.35 Below Prado 56350 Max WS 1860.84 88.20 90.36 90.50 0.001378 3.03 613.93 289.13 0.37 Below Prado 56258* Max WS 1858.53 88.07 90.23 90.37 0.001396 3.05 609.39 287.02 0.37 Below Prado 56165* Max WS 1857.00 87.94 90.10 90.24 0.001420 3.07 604.17 284.90 0.37 Below Prado 56072* Max WS 1854.97 87.81 89.96 90.11 0.001450 3.10 598.13 282.78 0.38 Below Prado 55979* Max WS 1853.19 87.69 89.82 89.97 0.001523 3.16 587.23 280.59 0.38 Below Prado 55886* Max WS 1851.26 87.56 89.67 89.83 0.001591 3.21 577.45 278.40 0.39 Below Prado 55793* Max WS 1849.25 87.43 89.51 89.68 0.001688 3.27 565.10 276.17 0.40 Below Prado 55700 Max WS 1847.34 87.30 89.34 89.51 0.001834 3.36 549.01 273.88 0.42 Below Prado 55608* Max WS 1844.95 87.13 89.17 89.35 0.001802 3.34 552.19 274.75 0.42 Below Prado 55515* Max WS 1842.59 86.95 89.02 89.18 0.001719 3.29 560.39 275.69 0.41 Below Prado 55423* Max WS 1839.99 86.78 88.86 89.03 0.001650 3.24 567.59 276.62 0.40 Below Prado 55330 Max WS 1837.54 86.60 88.73 88.88 0.001531 3.16 580.96 277.63 0.39 Below Prado 55240* Max WS 1835.15 86.48 88.59 88.74 0.001536 3.15 582.11 280.31 0.39 Below Prado 55150* Max WS 1832.44 86.37 88.45 88.60 0.001578 3.16 579.09 282.92 0.39 Below Prado 55060* Max WS 1829.18 86.25 88.31 88.46 0.001599 3.16 578.27 285.58 0.39 Below Prado 54970* Max WS 1825.15 86.13 88.16 88.32 0.001627 3.17 576.58 288.22 0.39 Below Prado 54880* Max WS 1820.62 86.02 88.01 88.17 0.001705 3.20 569.70 290.79 0.40 Below Prado 54790 Max WS 1814.43 85.90 87.85 88.01 0.001773 3.22 563.85 293.37 0.41 Below Prado 54692.5* Max WS 1807.58 85.70 87.69 87.84 0.001670 3.16 571.58 291.78 0.40 Below Prado 54595.0* Max WS 1800.71 85.50 87.54 87.69 0.001542 3.09 582.86 290.24 0.38 Below Prado 54497.5* Max WS 1794.84 85.30 87.40 87.54 0.001395 3.00 598.27 288.78 0.37 Below Prado 54400 Max WS 1789.40 85.10 87.29 87.42 0.001236 2.89 618.16 287.37 0.35 HEC-RAS Plan: South_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 54300.0* Max WS 1784.70 84.95 87.17 87.30 0.001187 2.86 623.01 285.49 0.34 Below Prado 54200.0* Max WS 1780.97 84.80 87.06 87.18 0.001134 2.83 629.27 283.63 0.33 Below Prado 54100.0* Max WS 1777.68 84.65 86.95 87.07 0.001075 2.79 637.02 281.79 0.33 Below Prado 54000 Max WS 1775.66 84.50 86.85 86.97 0.001013 2.75 646.40 279.99 0.32 Below Prado 53912* Max WS 1774.01 84.36 86.76 86.88 0.001004 2.77 640.34 271.92 0.32 Below Prado 53823* Max WS 1772.71 84.21 86.67 86.79 0.000982 2.78 636.69 263.90 0.32 Below Prado 53735* Max WS 1771.75 84.07 86.58 86.71 0.000979 2.82 629.35 255.84 0.32 Below Prado 53646* Max WS 1771.47 83.93 86.49 86.62 0.000980 2.85 621.04 247.78 0.32 Below Prado 53558* Max WS 1771.24 83.79 86.40 86.53 0.000987 2.90 611.63 239.71 0.32 Below Prado 53469* Max WS 1771.07 83.64 86.31 86.45 0.000984 2.93 603.82 231.69 0.32 Below Prado 53380 Max WS 1771.05 83.50 86.22 84.79 86.36 0.001002 2.99 592.19 223.61 0.32 Appendix D
Simultaneous Deflation HEC-RAS Model Output

HEC-RAS Plan: Short_Sim_Short River: Santa Ana River Reach: Below Prado Profile: Max WS Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 69601 Max WS 4849.86 144.20 148.00 148.32 0.001511 4.57 1060.73 288.30 0.42 Below Prado 69366 Max WS 4848.04 143.83 147.64 145.98 147.97 0.001504 4.59 1055.83 283.74 0.42 Below Prado 69341 Bridge
Below Prado 69313 Max WS 4847.47 143.66 147.06 147.47 0.002218 5.17 936.96 281.90 0.50 Below Prado 69200 Max WS 4846.70 143.44 146.79 147.22 0.002293 5.24 925.84 282.69 0.51 Below Prado 69176* Max WS 4846.51 143.39 146.74 147.16 0.002326 5.24 924.64 282.85 0.51 Below Prado 69152* Max WS 4846.39 143.34 146.68 147.11 0.002342 5.25 922.89 283.01 0.51 Below Prado 69128* Max WS 4846.14 143.29 146.62 147.05 0.002359 5.26 921.02 283.18 0.51 Below Prado 69104* Max WS 4845.97 143.24 146.56 146.99 0.002378 5.27 919.04 283.38 0.52 Below Prado 69080* Max WS 4845.89 143.20 146.50 146.94 0.002433 5.31 912.93 283.56 0.52 Below Prado 69056* Max WS 4845.79 143.15 146.44 146.88 0.002459 5.32 910.27 283.78 0.52 Below Prado 69032* Max WS 4845.61 143.10 146.38 146.82 0.002487 5.34 907.48 284.05 0.53 Below Prado 69009 Max WS 4845.62 143.05 146.31 146.76 0.002518 5.36 904.42 284.33 0.53 Below Prado 69004* Max WS 4845.61 143.04 146.30 146.75 0.002524 5.36 903.82 284.40 0.53 Below Prado 68999* Max WS 4845.61 143.03 146.29 146.74 0.002531 5.37 903.15 284.46 0.53 Below Prado 68994* Max WS 4845.61 143.02 146.28 146.72 0.002538 5.37 902.49 284.53 0.53 Below Prado 68989* Max WS 4845.59 143.01 146.26 146.71 0.002545 5.37 901.87 284.60 0.53 Below Prado 68985 Max WS 4845.59 143.00 146.25 145.14 146.70 0.002552 5.38 901.18 284.67 0.53 Below Prado 68977 Inl Struct
Below Prado 68969 Max WS 4839.77 132.80 139.73 139.82 0.000570 2.50 1939.28 280.00 0.17 Below Prado 68964* Max WS 4839.06 132.80 139.72 139.82 0.000575 2.51 1931.38 279.00 0.17 Below Prado 68959* Max WS 4839.53 132.80 139.72 139.82 0.000580 2.52 1923.48 278.00 0.17 Below Prado 68955* Max WS 4839.29 132.80 139.72 139.81 0.000585 2.53 1915.59 277.02 0.17 Below Prado 68950* Max WS 4839.28 132.80 139.71 139.81 0.000593 2.54 1908.03 277.48 0.17 Below Prado 68945* Max WS 4839.27 132.80 139.71 139.81 0.000599 2.55 1901.08 277.89 0.17 Below Prado 68940* Max WS 4839.06 132.80 139.71 139.81 0.000605 2.55 1894.71 278.26 0.17 Below Prado 68936* Max WS 4839.24 132.80 139.70 139.80 0.000611 2.56 1888.90 278.60 0.17 Below Prado 68931* Max WS 4839.04 132.80 139.70 139.80 0.000616 2.57 1883.66 278.90 0.17 Below Prado 68926* Max WS 4839.03 132.80 139.69 139.80 0.000620 2.58 1878.94 279.17 0.18 Below Prado 68922 Max WS 4839.21 132.80 139.69 139.79 0.000623 2.58 1874.71 279.40 0.18 Below Prado 68916 Max WS 4837.59 135.73 139.46 139.81 0.003983 4.43 1046.21 291.17 0.41 Below Prado 68808* Max WS 4834.25 135.51 139.14 139.49 0.001750 4.78 1011.92 287.61 0.45 Below Prado 68700 Max WS 4832.03 135.30 138.96 139.31 0.001713 4.76 1015.47 285.48 0.44 Below Prado 68547* Max WS 4829.42 134.95 138.74 139.06 0.001523 4.59 1052.71 286.22 0.42 Below Prado 68395 Max WS 4829.08 134.60 138.55 136.74 138.85 0.001324 4.39 1099.53 287.26 0.40 Below Prado 68222 Bridge
Below Prado 68050 Max WS 4820.85 134.10 137.59 137.97 0.001989 4.97 969.94 285.89 0.48 Below Prado 67866* Max WS 4816.10 133.73 137.23 137.61 0.001970 4.96 970.84 284.83 0.47 Below Prado 67683* Max WS 4809.16 133.37 136.87 137.25 0.001969 4.96 968.84 283.77 0.47 Below Prado 67500 Max WS 4800.71 133.00 136.52 136.90 0.001934 4.94 971.82 282.80 0.47 Below Prado 67333* Max WS 4793.92 132.62 136.24 136.59 0.001739 4.74 1012.37 290.34 0.45 Below Prado 67166* Max WS 4789.83 132.24 136.01 136.32 0.001517 4.47 1070.62 302.02 0.42 Below Prado 67000 Max WS 4787.81 131.86 135.82 136.09 0.001239 4.16 1151.81 311.36 0.38 Below Prado 66922 Max WS 4787.54 131.80 135.70 133.93 135.99 0.001428 4.32 1108.55 314.20 0.41 Below Prado 66884 Bridge
Below Prado 66847 Max WS 4782.27 131.60 134.96 135.37 0.002212 5.12 934.08 285.29 0.50 Below Prado 66723* Max WS 4776.98 131.30 134.71 135.10 0.002120 5.06 944.36 284.36 0.49 Below Prado 66600 Max WS 4773.72 131.00 134.47 134.85 0.001996 4.97 961.22 284.31 0.48 Below Prado 66433* Max WS 4767.26 130.67 134.14 134.52 0.001994 4.96 960.42 284.04 0.48 Below Prado 66266* Max WS 4760.39 130.33 133.81 134.19 0.001959 4.94 964.44 283.85 0.47 Below Prado 66100 Max WS 4755.93 130.00 133.49 133.87 0.001941 4.92 966.34 283.63 0.47 Below Prado 65933* Max WS 4750.67 129.67 133.18 133.55 0.001909 4.89 971.02 284.00 0.47 Below Prado 65766* Max WS 4745.79 129.33 132.87 133.24 0.001836 4.83 982.37 284.46 0.46 Below Prado 65600 Max WS 4742.99 129.00 132.58 132.94 0.001766 4.77 994.31 284.97 0.45 Below Prado 65425* Max WS 4739.29 128.73 132.26 132.62 0.001860 4.84 978.45 285.02 0.46 Below Prado 65250* Max WS 4736.59 128.45 131.91 132.28 0.001986 4.94 958.95 285.00 0.47 Below Prado 65075* Max WS 4731.00 128.18 131.51 131.91 0.002254 5.13 922.19 284.70 0.50 Below Prado 64900 Max WS 4731.13 127.90 130.99 131.47 0.002870 5.52 856.58 283.92 0.56 Below Prado 64734* Max WS 4730.34 127.34 130.58 131.02 0.002518 5.31 890.06 283.15 0.53 Below Prado 64568 Max WS 4729.41 126.78 130.23 130.63 0.002203 5.11 926.21 282.91 0.50 Below Prado 64559* Max WS 4728.73 126.78 130.21 130.61 0.002211 5.11 925.04 282.85 0.50 Below Prado 64550* Max WS 4728.58 126.78 130.18 130.59 0.002215 5.12 924.43 282.80 0.50 Below Prado 64541* Max WS 4728.53 126.79 130.16 130.57 0.002258 5.15 919.04 282.70 0.50 Below Prado 64532* Max WS 4728.50 126.79 130.14 130.55 0.002279 5.16 916.32 282.65 0.51 Below Prado 64522* Max WS 4728.47 126.79 130.11 130.53 0.002316 5.19 911.80 282.56 0.51 Below Prado 64513* Max WS 4728.44 126.79 130.08 130.51 0.002356 5.21 907.03 282.50 0.51 Below Prado 64504* Max WS 4728.42 126.80 130.05 130.49 0.002442 5.27 897.18 282.38 0.52 Below Prado 64495 Max WS 4728.39 126.80 130.02 130.46 0.002509 5.31 889.87 282.30 0.53 Below Prado 64490* Max WS 4728.37 126.80 130.01 130.45 0.002549 5.34 885.58 282.24 0.53 Below Prado 64486 Max WS 4728.36 126.80 129.99 128.92 130.44 0.002591 5.37 881.11 282.20 0.54 Below Prado 64478 Inl Struct
Below Prado 64470 Max WS 4695.32 117.80 125.06 125.15 0.000495 2.39 1961.04 270.00 0.16 Below Prado 64465* Max WS 4695.31 117.80 125.06 125.15 0.000495 2.40 1960.39 270.00 0.16 Below Prado 64460* Max WS 4694.72 117.80 125.06 125.15 0.000496 2.40 1959.74 270.00 0.16 Below Prado 64455* Max WS 4694.71 117.80 125.06 125.15 0.000498 2.40 1959.21 270.99 0.16 Below Prado 64450* Max WS 4694.69 117.80 125.05 125.14 0.000499 2.40 1959.25 272.39 0.16 Below Prado 64445* Max WS 4694.10 117.80 125.05 125.14 0.000501 2.40 1959.87 273.77 0.16 Below Prado 64440* Max WS 4694.09 117.80 125.05 125.14 0.000501 2.39 1961.05 275.13 0.16 Below Prado 64435* Max WS 4694.08 117.80 125.05 125.14 0.000502 2.39 1962.76 276.48 0.16 HEC-RAS Plan: Short_Sim_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 64430* Max WS 4694.07 117.80 125.04 125.13 0.000501 2.39 1965.03 277.80 0.16 Below Prado 64426* Max WS 4694.05 117.80 125.04 125.13 0.000501 2.39 1967.81 279.11 0.16 Below Prado 64421 Max WS 4693.51 117.80 125.04 125.13 0.000499 2.38 1971.13 280.40 0.16 Below Prado 64416 Max WS 4685.78 120.80 124.87 125.13 0.003113 4.11 1139.57 290.19 0.37 Below Prado 64308* Max WS 4670.41 120.60 124.64 124.90 0.001131 4.12 1134.34 290.18 0.37 Below Prado 64200 Max WS 4665.91 120.40 124.54 124.79 0.001033 4.00 1165.16 290.16 0.35 Below Prado 64063* Max WS 4660.00 120.20 124.41 124.65 0.000988 3.96 1176.09 287.61 0.35 Below Prado 63927 Max WS 4654.31 120.00 124.28 122.09 124.52 0.000945 3.93 1184.89 283.56 0.34 Below Prado 63878 Bridge
Below Prado 63829 Max WS 4626.65 119.50 123.49 123.76 0.001233 4.16 1111.91 297.64 0.38 Below Prado 63600 Max WS 4618.86 119.20 123.24 123.50 0.001097 4.07 1135.53 288.89 0.36 Below Prado 63400* Max WS 4611.78 119.05 123.01 123.27 0.001175 4.15 1110.82 288.60 0.37 Below Prado 63200 Max WS 4604.09 118.90 122.75 123.03 0.001286 4.27 1079.44 288.21 0.39 Below Prado 63000* Max WS 4599.84 118.45 122.55 122.80 0.001035 3.99 1153.34 289.32 0.35 Below Prado 62800 Max WS 4596.66 118.00 122.40 122.62 0.000816 3.71 1240.47 290.61 0.32 Below Prado 62601 Max WS 4595.15 117.84 122.24 119.90 122.45 0.000827 3.73 1233.23 289.57 0.32 Below Prado 62451 Bridge
Below Prado 62301 Max WS 4572.98 117.35 120.70 121.08 0.002028 4.90 933.79 285.52 0.48 Below Prado 62300 Max WS 4575.95 117.20 120.74 121.07 0.001668 4.60 993.73 287.68 0.44 Below Prado 62100* Max WS 4563.70 116.90 120.40 120.74 0.001730 4.65 981.39 287.78 0.44 Below Prado 61900 Max WS 4544.57 116.60 120.04 120.38 0.001824 4.72 963.46 287.80 0.45 Below Prado 61733* Max WS 4527.19 116.27 119.75 120.09 0.001727 4.63 977.93 288.43 0.44 Below Prado 61566* Max WS 4511.88 115.93 119.50 119.81 0.001583 4.50 1002.87 289.22 0.43 Below Prado 61400 Max WS 4499.60 115.60 119.27 119.56 0.001435 4.36 1032.47 290.11 0.41 Below Prado 61200* Max WS 4485.96 115.30 118.99 119.28 0.001390 4.31 1040.06 289.84 0.40 Below Prado 61000 Max WS 4474.80 115.00 118.73 119.01 0.001336 4.26 1050.82 289.59 0.39 Below Prado 60800* Max WS 4471.22 114.60 118.51 118.77 0.001141 4.05 1103.08 290.73 0.37 Below Prado 60600 Max WS 4469.67 114.20 118.33 116.22 118.56 0.000951 3.83 1166.92 292.14 0.34 Below Prado 60550 Bridge
Below Prado 60505 Max WS 4469.67 113.95 118.30 118.51 0.000808 3.65 1223.45 290.93 0.31 Below Prado 60500 Max WS 4469.12 113.95 118.04 115.97 118.28 0.000990 3.89 1149.07 289.79 0.34 Below Prado 60372 Bridge
Below Prado 60245 Max WS 4468.40 113.70 116.80 117.22 0.002553 5.21 857.04 283.68 0.53 Below Prado 60222* Max WS 4468.47 113.66 116.73 117.16 0.002621 5.26 850.12 283.55 0.54 Below Prado 60199* Max WS 4468.46 113.62 116.66 117.10 0.002711 5.31 841.38 283.39 0.54 Below Prado 60176* Max WS 4468.44 113.58 116.59 117.04 0.002816 5.37 831.60 283.22 0.55 Below Prado 60153 Max WS 4468.43 113.54 116.51 116.97 0.002942 5.45 820.57 283.02 0.56 Below Prado 60148* Max WS 4468.42 113.51 116.50 116.96 0.002863 5.40 827.35 283.10 0.56 Below Prado 60144* Max WS 4468.41 113.48 116.50 116.94 0.002787 5.36 834.20 283.18 0.55 Below Prado 60139* Max WS 4468.42 113.46 116.49 116.93 0.002756 5.34 837.05 283.21 0.55 Below Prado 60134* Max WS 4468.42 113.43 116.48 116.92 0.002682 5.29 844.01 283.29 0.54 Below Prado 60130 Max WS 4468.41 113.40 116.48 115.43 116.90 0.002610 5.25 851.00 283.37 0.53 Below Prado 60122 Inl Struct
Below Prado 60115 Max WS 4466.45 103.40 110.58 110.66 0.000477 2.27 1966.30 290.72 0.15 Below Prado 60110* Max WS 4466.30 103.40 110.57 110.65 0.000479 2.28 1957.57 287.61 0.15 Below Prado 60105* Max WS 4466.43 103.40 110.57 110.65 0.000480 2.29 1950.15 284.50 0.15 Below Prado 60101* Max WS 4466.15 103.40 110.57 110.65 0.000480 2.30 1944.05 281.40 0.15 Below Prado 60096* Max WS 4466.29 103.40 110.57 110.65 0.000478 2.30 1939.26 278.32 0.15 Below Prado 60092* Max WS 4466.28 103.40 110.56 110.65 0.000476 2.31 1935.77 275.25 0.15 Below Prado 60087* Max WS 4466.41 103.40 110.56 110.64 0.000473 2.31 1933.59 272.20 0.15 Below Prado 60082* Max WS 4466.28 103.40 110.56 110.64 0.000470 2.31 1932.66 270.00 0.15 Below Prado 60078* Max WS 4466.15 103.40 110.56 110.64 0.000470 2.31 1932.07 270.00 0.15 Below Prado 60073* Max WS 4466.14 103.40 110.55 110.64 0.000471 2.31 1931.47 270.00 0.15 Below Prado 60069 Max WS 4466.38 103.40 110.55 110.63 0.000471 2.31 1930.88 270.00 0.15 Below Prado 60061 Max WS 4465.32 106.93 110.28 110.65 0.005461 4.83 924.47 281.45 0.47 Below Prado 59931 Max WS 4458.02 106.80 109.69 110.11 0.002746 5.19 859.37 302.84 0.54 Below Prado 59766* Max WS 4451.62 106.40 109.34 109.70 0.002320 4.82 924.04 320.67 0.50 Below Prado 59601 Max WS 4446.96 106.00 109.06 109.36 0.001799 4.36 1018.86 338.77 0.44 Below Prado 59434* Max WS 4441.65 105.83 108.75 109.05 0.001899 4.35 1019.94 354.42 0.45 Below Prado 59267* Max WS 4434.88 105.67 108.40 108.71 0.002164 4.45 996.48 369.84 0.48 Below Prado 59101 Max WS 4418.95 105.50 107.94 108.29 0.002893 4.77 925.76 384.81 0.54 Below Prado 58934* Max WS 4405.26 104.99 107.55 107.85 0.002364 4.45 989.24 392.23 0.49 Below Prado 58767* Max WS 4398.67 104.47 107.27 107.52 0.001671 3.98 1105.76 400.15 0.42 Below Prado 58601 Max WS 4396.71 103.96 107.10 107.29 0.001102 3.48 1262.87 408.43 0.35 Below Prado 58464 Max WS 4396.05 103.63 106.88 107.12 0.001374 3.94 1115.68 353.80 0.39 Below Prado 58353 Max WS 4395.99 103.44 106.75 105.16 106.98 0.001224 3.79 1160.79 357.88 0.37 Below Prado 58307 Bridge
Below Prado 58260 Max WS 4395.82 103.30 106.05 106.37 0.002246 4.55 966.75 357.38 0.49 Below Prado 58252* Max WS 4395.73 103.28 106.03 106.35 0.002240 4.54 967.88 357.72 0.49 Below Prado 58243* Max WS 4395.80 103.26 106.01 106.33 0.002234 4.54 969.01 358.06 0.49 Below Prado 58234* Max WS 4395.76 103.24 106.00 106.31 0.002228 4.53 970.18 358.41 0.49 Below Prado 58225* Max WS 4395.73 103.21 105.98 106.30 0.002186 4.50 976.16 358.82 0.48 Below Prado 58216* Max WS 4395.77 103.19 105.96 106.28 0.002178 4.50 977.52 359.17 0.48 Below Prado 58207 Max WS 4395.75 103.17 105.94 106.26 0.002171 4.49 978.91 359.53 0.48 Below Prado 58198 Max WS 4395.74 103.15 105.86 104.94 106.24 0.002740 4.94 890.26 337.92 0.54 Below Prado 58188 Inl Struct
Below Prado 58178 Max WS 4336.98 93.15 102.17 102.20 0.000048 1.42 3055.06 357.13 0.09 Below Prado 58174* Max WS 4336.20 93.15 102.17 102.20 0.000047 1.41 3068.68 358.59 0.09 Below Prado 58169* Max WS 4336.97 93.15 102.17 102.20 0.000047 1.41 3082.43 360.06 0.08 HEC-RAS Plan: Short_Sim_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 58164* Max WS 4337.72 93.15 102.17 102.20 0.000046 1.40 3096.04 361.51 0.08 Below Prado 58159* Max WS 4336.96 93.15 102.17 102.20 0.000046 1.39 3109.69 362.97 0.08 Below Prado 58154* Max WS 4338.45 93.15 102.17 102.20 0.000046 1.39 3123.30 364.42 0.08 Below Prado 58149* Max WS 4336.21 93.15 102.17 102.20 0.000045 1.38 3137.04 365.89 0.08 Below Prado 58144* Max WS 4337.69 93.15 102.17 102.20 0.000045 1.38 3150.65 367.33 0.08 Below Prado 58139* Max WS 4337.68 93.15 102.17 102.20 0.000044 1.37 3164.28 368.80 0.08 Below Prado 58134* Max WS 4337.67 93.15 102.17 102.20 0.000044 1.36 3177.88 370.24 0.08 Below Prado 58130* Max WS 4336.94 93.15 102.17 102.20 0.000043 1.36 3191.53 371.69 0.08 Below Prado 58125* Max WS 4336.93 93.15 102.17 102.20 0.000043 1.35 3205.15 373.15 0.08 Below Prado 58120* Max WS 4336.92 93.15 102.17 102.20 0.000043 1.35 3218.74 374.59 0.08 Below Prado 58115* Max WS 4337.62 93.15 102.17 102.20 0.000042 1.34 3232.40 376.05 0.08 Below Prado 58110* Max WS 4336.21 93.15 102.17 102.20 0.000042 1.34 3246.00 377.49 0.08 Below Prado 58105* Max WS 4337.60 93.15 102.17 102.20 0.000042 1.33 3259.64 378.95 0.08 Below Prado 58100 Max WS 4336.91 93.15 102.17 102.20 0.000041 1.32 3273.18 380.39 0.08 Below Prado 58094 Max WS 4332.71 97.40 102.11 102.21 0.000315 2.43 1786.34 387.74 0.20 Below Prado 57997* Max WS 4326.46 97.20 102.03 102.17 0.000500 3.00 1442.22 322.38 0.25 Below Prado 57900 Max WS 4315.01 97.00 101.86 102.10 0.000975 3.91 1103.59 273.99 0.34 Below Prado 57800* Max WS 4312.46 96.83 101.74 102.00 0.001084 4.06 1061.20 269.21 0.36 Below Prado 57700* Max WS 4306.51 96.67 101.60 101.88 0.001282 4.27 1007.88 268.93 0.39 Below Prado 57600 Max WS 4299.76 96.50 101.42 101.73 0.001760 4.44 967.61 308.75 0.44 Below Prado 57550* Max WS 4296.80 96.38 101.32 101.64 0.001867 4.53 948.86 307.69 0.45 Below Prado 57500* Max WS 4294.89 96.25 101.21 101.54 0.001995 4.63 928.45 306.39 0.47 Below Prado 57450* Max WS 4292.67 96.12 101.09 101.44 0.002166 4.75 904.10 304.97 0.49 Below Prado 57400 Max WS 4290.69 96.00 100.95 101.33 0.002422 4.92 872.29 303.25 0.51 Below Prado 57375* Max WS 4289.98 95.94 100.86 101.26 0.002608 5.10 841.01 292.62 0.53 Below Prado 57350* Max WS 4289.31 95.88 100.76 101.20 0.002798 5.29 811.00 281.75 0.55 Below Prado 57325* Max WS 4288.98 95.81 100.66 101.12 0.003005 5.47 784.27 273.38 0.57 Below Prado 57300* Max WS 4288.93 95.75 100.55 101.05 0.003271 5.68 755.71 265.52 0.59 Below Prado 57275* Max WS 4288.66 95.69 100.42 100.96 0.003604 5.90 726.49 258.72 0.62 Below Prado 57250* Max WS 4288.98 95.62 100.27 100.87 0.004054 6.17 695.52 253.38 0.66 Below Prado 57225* Max WS 4289.06 95.56 100.10 100.76 0.004772 6.53 656.47 247.77 0.71 Below Prado 57200 Max WS 4289.21 95.50 99.93 100.66 0.003193 6.84 627.19 163.16 0.61 Below Prado 57175* Max WS 4289.25 95.45 99.80 100.56 0.003407 6.99 613.87 162.37 0.63 Below Prado 57150* Max WS 4289.27 95.40 99.68 100.46 0.003613 7.12 602.09 161.66 0.65 Below Prado 57125* Max WS 4289.22 95.35 99.55 100.37 0.003846 7.27 589.80 160.91 0.67 Below Prado 57100* Max WS 4289.19 95.30 99.41 100.27 0.004158 7.46 574.82 160.00 0.69 Below Prado 57075 Max WS 4289.18 95.25 99.24 100.16 0.004608 7.72 555.71 158.84 0.73 Below Prado 57067* Max WS 4289.17 95.24 99.32 100.13 0.003915 7.21 594.84 166.73 0.67 Below Prado 57059* Max WS 4289.17 95.24 99.38 100.10 0.003433 6.80 630.51 174.87 0.63 Below Prado 57050 Max WS 4289.17 95.23 99.43 98.24 100.07 0.003009 6.42 668.49 183.41 0.59 Below Prado 57040 Inl Struct
Below Prado 57030 Max WS 4245.69 85.25 92.61 92.65 0.000076 1.59 2671.48 375.73 0.11 Below Prado 57020* Max WS 4244.98 85.25 92.61 92.65 0.000076 1.59 2671.22 375.73 0.11 Below Prado 57010* Max WS 4245.64 85.25 92.61 92.65 0.000076 1.59 2670.96 375.73 0.11 Below Prado 57000* Max WS 4244.96 85.24 92.61 92.65 0.000076 1.59 2674.46 375.75 0.10 Below Prado 56990* Max WS 4244.94 85.24 92.61 92.65 0.000076 1.59 2674.21 375.75 0.10 Below Prado 56980* Max WS 4244.91 85.24 92.61 92.65 0.000076 1.59 2673.95 375.75 0.10 Below Prado 56970* Max WS 4244.89 85.24 92.61 92.65 0.000076 1.59 2673.69 375.74 0.10 Below Prado 56960* Max WS 4244.26 85.23 92.61 92.65 0.000076 1.59 2677.19 375.77 0.10 Below Prado 56950 Max WS 4244.24 85.23 92.61 92.65 0.000076 1.59 2676.92 375.76 0.10 Below Prado 56947 Max WS 4230.82 89.44 92.44 92.68 0.001524 3.96 1067.54 362.51 0.41 Below Prado 56868* Max WS 4223.49 89.33 92.34 92.57 0.001405 3.82 1105.90 373.31 0.39 Below Prado 56789* Max WS 4215.50 89.22 92.25 92.46 0.001284 3.67 1147.98 384.13 0.37 Below Prado 56710* Max WS 4211.30 89.11 92.17 92.36 0.001167 3.53 1193.96 394.95 0.36 Below Prado 56630 Max WS 4206.73 89.00 92.10 92.28 0.001054 3.38 1243.99 405.77 0.34 Below Prado 56537* Max WS 4201.42 88.73 91.98 92.18 0.001099 3.56 1181.24 368.70 0.35 Below Prado 56444* Max WS 4195.89 88.47 91.84 92.07 0.001217 3.82 1097.50 331.68 0.37 Below Prado 56350 Max WS 4186.69 88.20 91.67 91.95 0.001418 4.19 998.54 294.70 0.40 Below Prado 56258* Max WS 4180.36 88.07 91.54 91.82 0.001444 4.23 989.33 292.59 0.41 Below Prado 56165* Max WS 4174.30 87.94 91.40 91.68 0.001476 4.26 979.14 290.46 0.41 Below Prado 56072* Max WS 4168.00 87.81 91.25 91.54 0.001515 4.31 967.83 288.32 0.41 Below Prado 55979* Max WS 4161.78 87.69 91.10 91.40 0.001583 4.37 951.32 286.11 0.42 Below Prado 55886* Max WS 4155.99 87.56 90.94 91.25 0.001649 4.44 936.11 283.91 0.43 Below Prado 55793* Max WS 4149.65 87.43 90.78 91.09 0.001733 4.52 918.44 281.66 0.44 Below Prado 55700 Max WS 4140.82 87.30 90.60 90.93 0.001842 4.61 897.61 279.37 0.45 Below Prado 55608* Max WS 4133.54 87.13 90.43 90.76 0.001812 4.58 902.18 280.15 0.45 Below Prado 55515* Max WS 4125.40 86.95 90.28 90.60 0.001750 4.52 911.75 281.00 0.44 Below Prado 55423* Max WS 4117.40 86.78 90.13 90.44 0.001700 4.48 919.64 281.83 0.44 Below Prado 55330 Max WS 4110.19 86.60 89.98 90.28 0.001622 4.40 933.07 282.73 0.43 Below Prado 55240* Max WS 4101.11 86.48 89.84 90.14 0.001618 4.38 936.04 285.43 0.43 Below Prado 55150* Max WS 4093.05 86.37 89.70 89.99 0.001637 4.38 935.04 288.08 0.43 Below Prado 55060* Max WS 4084.36 86.25 89.55 89.85 0.001638 4.36 937.06 290.77 0.43 Below Prado 54970* Max WS 4076.13 86.13 89.41 89.70 0.001641 4.34 938.88 293.47 0.43 Below Prado 54880* Max WS 4068.37 86.02 89.26 89.55 0.001668 4.34 936.43 296.10 0.43 Below Prado 54790 Max WS 4058.78 85.90 89.11 89.40 0.001678 4.33 936.85 298.78 0.43 Below Prado 54692.5* Max WS 4049.88 85.70 88.96 89.24 0.001611 4.28 945.17 297.22 0.42 Below Prado 54595.0* Max WS 4042.36 85.50 88.81 89.09 0.001537 4.23 955.63 295.70 0.41 Below Prado 54497.5* Max WS 4036.77 85.30 88.67 88.94 0.001456 4.17 968.44 294.22 0.41 Below Prado 54400 Max WS 4031.97 85.10 88.55 88.81 0.001370 4.10 983.70 292.78 0.39 HEC-RAS Plan: Short_Sim_Short River: Santa Ana River Reach: Below Prado Profile: Max WS (Continued) Reach River Sta Profile Q Total Min Ch El W.S. Elev Crit W.S. E.G. Elev E.G. Slope Vel Chnl Flow Area Top Width Froude # Chl (cfs) (ft) (ft) (ft) (ft) (ft/ft) (ft/s) (sq ft) (ft)
Below Prado 54300.0* Max WS 4027.02 84.95 88.41 88.67 0.001369 4.11 980.58 290.80 0.39 Below Prado 54200.0* Max WS 4023.35 84.80 88.27 88.54 0.001369 4.12 977.36 288.83 0.39 Below Prado 54100.0* Max WS 4019.69 84.65 88.14 88.40 0.001370 4.13 973.98 286.84 0.39 Below Prado 54000 Max WS 4017.21 84.50 88.00 88.26 0.001373 4.14 970.44 284.86 0.40 Below Prado 53912* Max WS 4015.93 84.36 87.86 88.14 0.001461 4.27 941.09 276.58 0.41 Below Prado 53823* Max WS 4014.35 84.21 87.71 88.01 0.001558 4.40 911.80 268.30 0.42 Below Prado 53735* Max WS 4013.27 84.07 87.54 87.86 0.001712 4.59 875.12 259.89 0.44 Below Prado 53646* Max WS 4012.40 83.93 87.34 87.70 0.001932 4.82 832.68 251.40 0.47 Below Prado 53558* Max WS 4011.79 83.79 87.11 87.52 0.002279 5.13 781.39 242.72 0.50 Below Prado 53469* Max WS 4011.59 83.64 86.80 87.29 0.002870 5.59 718.23 233.79 0.56 Below Prado 53380 Max WS 4011.50 83.50 86.24 85.71 86.94 0.005010 6.72 596.94 223.70 0.73 Appendix E

Appendix E – Existing vs. Proposed Comparisons

Appendix E
Existing vs Proposed Condition Comparison – Water Surface Elevation
WSE Comparison
HEC-RAS Cross
Section
Existing
Condition WSE
[ft]
Proposed
Condition WSE
[ft]
Difference
(Proposed -
Existing) [ft]
HEC-RAS Cross
Section
Existing
Condition WSE
[ft]
Proposed
Condition WSE
[ft]
Difference
(Proposed -
Existing) [ft]
77600 184.18 184.18 0 71481* 163.64 163.73 0.09
77433* 183.85 183.85 0 71281 163.23 163.33 0.1
77266* 183.51 183.51 0 71201 163.05 163.16 0.11
77100 183.16 183.16 0 71081* 162.91 163.03 0.12
76933* 182.85 182.85 0 70961 162.84 162.96 0.12
76766* 182.56 182.56 0 70894
76600 182.27 182.27 0 70827 162.45 162.59 0.14
76433* 181.93 181.93 0 70714 162.37 162.5 0.13
76266* 181.57 181.57 0 70601 162.28 162.48 0.2
76100 181.21 181.21 0 70434* 162.1 162.32 0.22
75900* 180.85 180.85 0 70267* 161.62 161.68 0.06
75700* 180.48 180.48 0 70101 161.25 161.08 -0.17
75500* 180.11 180.11 0 69934* 161.05 160.98 -0.07
75300* 179.75 179.75 0 69767* 160.69 160.63 -0.06
75100 179.4 179.4 0 69601 160.5 160.44 -0.06
74969 179.27 179.27 0 69366 160.26 160.24 -0.02
74927 69341
74886 178.87 178.87 0 69313 159.55 159.62 0.07
74862* 178.78 178.78 0 69200 159.25 159.25 0
74839* 178.72 178.72 0 69176* 159.14 159.14 0
74815* 178.73 178.73 0 69152* 159.11 159.11 0
74792* 178.66 178.66 0 69128* 159.07 159.07 0
74768 178.66 178.66 0 69104* 159.02 159.02 0
74745* 178.65 178.65 0 69080* 158.97 158.97 0
74721* 178.63 178.63 0 69056* 158.94 158.94 0
74697 178.57 178.57 0 69032* 158.92 158.92 0
74674* 178.48 178.48 0 69009 158.93 158.93 0
74650* 178.39 178.39 0 69004 158.93 158.93 0
74627* 178.3 178.3 0 68999 158.94 158.94 0
74603 178.24 178.24 0 68994 158.95 158.95 0
74580* 178.2 178.2 0 68989 158.96 158.96 0
74556 178.21 178.21 0 68985 158.97 158.97 0
74552* 178.2 178.2 0 68969 152.76 152.82 0.06
74547 178.2 178.2 0 68964 152.78 152.84 0.06
74542 178.21 178.21 0 68959 152.76 152.83 0.07
74537 178.22 178.22 0 68955 152.75 152.83 0.08
74533 178.21 178.21 0 68950 152.75 152.82 0.07
74515 169.81 169.84 0.03 68945 152.75 152.82 0.07
74510 169.8 169.84 0.04 68940 152.75 152.81 0.06
74505 169.81 169.84 0.03 68936 152.74 152.81 0.07
74500 169.8 169.84 0.04 68931 152.74 152.8 0.06
74496 169.8 169.83 0.03 68926 152.72 152.79 0.07
74491 169.79 169.82 0.03 68922 152.71 152.78 0.07
74486 169.78 169.81 0.03 68916 152.13 152.21 0.08
74481 169.77 169.8 0.03 68808* 151.2 151.31 0.11
74477 169.75 169.79 0.04 68700 151.28 151.39 0.11
74469 169.02 169.07 0.05 68547* 151.14 151.25 0.11
74313* 168.51 168.56 0.05 68395 150.82 150.94 0.12
74157* 168.22 168.29 0.07 68222
74001 167.96 168.03 0.07 68050 149.14 149.49 0.35
73801* 167.65 167.72 0.07 67866* 148.73 149.06 0.33
73601 167.39 167.47 0.08 67683* 148.42 148.7 0.28
73467* 167.08 167.17 0.09 67500 148.07 148.38 0.31
73334 166.86 166.97 0.11 67341 147.74 147.85 0.11
73324 67324
73314 166.38 166.5 0.12 67313 147.68 147.59 -0.09
73207* 166.12 166.28 0.16 67166* 147.42 147.43 0.01
73101 166.05 166.16 0.11 67000 147.31 147.32 0.01
72934* 165.72 165.89 0.17 66922 147.16 147.11 -0.05
72767 165.46 165.77 0.31 66884
72601 165.18 165.42 0.24 66847 146.31 146.23 -0.08
72401 164.9 165.29 0.39 66723* 145.99 145.99 0
72201 164.63 165.05 0.42 66600 145.78 145.78 0
72027 164.43 164.87 0.44 66433* 145.43 145.43 0
71854* 164.22 164.63 0.41 66266* 145.08 145.08 0
71772 164.12 164.62 0.5 66100 144.73 144.73 0
71740 65933* 144.39 144.39 0
71718 164.06 164.29 0.23 65766* 144.06 144.06 0
71681 164 164.11 0.11
Orangewood Ave. Bridge
Proposed Pedestrian Bridge
Ball Road Bridge
Katella Ave Bridge
OCTA RR Bridge
57 Freeway Bridge
Proposed Pedestiran BridgeSPT RR Bridge
Appendix E
Existing vs Proposed Condition Comparison – Velocity
Velocity Comparison
HEC-RAS Cross
Section
Existing
Condition
Velocity [ft/s]
Proposed
Condition
Velocity [ft/s]
Difference
(Proposed -
Existing) [ft/s]
HEC-RAS Cross
Section
Existing
Condition
Velocity [ft/s]
Proposed
Condition
Velocity [ft/s]
Difference
(Proposed -
Existing) [ft/s]
77600 10.01 10.01 0 71481* 9.48 9.41 -0.07
77433* 10.08 10.08 0 71281 9.86 9.78 -0.08
77266* 10.19 10.19 0 71201 10.02 9.92 -0.1
77100 10.29 10.29 0 71081* 9.77 9.67 -0.1
76933* 10.24 10.24 0 70961 9.29 9.19 -0.1
76766* 10.18 10.18 0 70894
76600 10.12 10.12 0 70827 9.51 9.4 -0.11
76433* 10.21 10.21 0 70714 9.16 9.09 -0.07
76266* 10.34 10.34 0 70601 8.94 8.53 -0.41
76100 10.47 10.47 0 70434* 8.87 8.45 -0.42
75900* 10.4 10.4 0 70267* 9.73 9.88 0.15
75700* 10.32 10.32 0 70101 10.13 10.77 0.64
75500* 10.24 10.24 0 69934* 9.9 10.02 0.12
75300* 10.15 10.15 0 69767* 10.25 10.31 0.06
75100 10.06 10.06 0 69601 10.01 10.06 0.05
74969 9.65 9.65 0 69366 9.66 9.52 -0.14
74927 69341
74886 9.92 9.92 0 69313 10.1 9.87 -0.23
74862* 10.06 10.06 0 69200 10.43 10.43 0
74839* 10.1 10.1 0 69176* 10.62 10.62 0
74815* 9.85 9.85 0 69152* 10.59 10.59 0
74792* 9.95 9.95 0 69128* 10.58 10.58 0
74768 9.77 9.77 0 69104* 10.62 10.62 0
74745* 9.63 9.63 0 69080* 10.64 10.64 0
74721* 9.58 9.58 0 69056* 10.57 10.57 0
74697 9.63 9.63 0 69032* 10.52 10.52 0
74674* 9.8 9.8 0 69009 10.31 10.31 0
74650* 9.95 9.95 0 69004 10.26 10.26 0
74627* 10.08 10.08 0 68999 10.15 10.15 0
74603 10.16 10.16 0 68994 10.05 10.05 0
74580* 10.12 10.12 0 68989 9.95 9.95 0
74556 9.91 9.91 0 68985 9.86 9.86 0
74552* 9.88 9.88 0 68969 8.21 8.18 -0.03
74547 9.87 9.87 0 68964 8.03 8 -0.03
74542 9.77 9.77 0 68959 8.06 8.03 -0.03
74537 9.66 9.66 0 68955 8.09 7.97 -0.12
74533 9.67 9.67 0 68950 8 7.96 -0.04
74515 7.77 7.75 -0.02 68945 7.96 7.92 -0.04
74510 7.73 7.71 -0.02 68940 7.93 7.9 -0.03
74505 7.66 7.64 -0.02 68936 7.91 7.88 -0.03
74500 7.6 7.59 -0.01 68931 7.88 7.85 -0.03
74496 7.58 7.56 -0.02 68926 7.9 7.86 -0.04
74491 7.58 7.56 -0.02 68922 7.92 7.89 -0.03
74486 7.59 7.57 -0.02 68916 9.78 9.72 -0.06
74481 7.59 7.57 -0.02 68808* 11.53 11.42 -0.11
74477 7.6 7.59 -0.01 68700 10.37 10.28 -0.09
74469 9.98 9.93 -0.05 68547* 9.97 9.88 -0.09
74313* 10.21 10.16 -0.05 68395 10.22 10.12 -0.1
74157* 10.22 10.16 -0.06 68222
74001 10.16 10.1 -0.06 68050 11.43 10.97 -0.46
73801* 10.01 9.94 -0.07 67866* 11.5 11.18 -0.32
73601 9.71 9.63 -0.08 67683* 11.26 11.12 -0.14
73467* 9.98 9.89 -0.09 67500 11.19 10.92 -0.27
73334 9.91 9.81 -0.1 67341 11.22 11.49 0.27
73324 67324
73314 10.37 10.26 -0.11 67313 11.23 11.69 0.46
73207* 10.51 10.33 -0.18 67166* 11.12 11.11 -0.01
73101 9.95 9.99 0.04 67000 10.34 10.33 -0.01
72934* 10.07 9.92 -0.15 66922 10.38 10.55 0.17
72767 9.96 9.3 -0.66 66884
72601 9.97 9.59 -0.38 66847 11.24 11.57 0.33
72401 9.76 8.89 -0.87 66723* 11.36 11.36 0
72201 9.62 8.85 -0.77 66600 11.15 11.15 0
72027 9.35 8.75 -0.6 66433* 11.19 11.19 0
71854* 9.23 8.87 -0.36 66266* 11.21 11.21 0
71772 9.21 8.43 -0.78 66100 11.25 11.25 0
71740 65933* 11.23 11.23 0
71718 9.17 8.56 -0.61 65766* 11.21 11.21 0
71681 9.2 9.02 -0.18
Orangewood Ave. Bridge
Proposed Pedestrian Bridge
Katella Ave Bridge
Ball Road Bridge OCTA RR Bridge
57 Freeway Bridge
SPT RR Bridge Proposed Pedestiran Bridge

Appendix B. Attachments to Letter 7 from Shiishongna Tongva Nation

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Coalition of CA State Tribes
1405 Oxley Street
South Pasadena, CA 91030
July 15, 2024

To Whom It May Concern:

The California Coalition of State Tribes (CCST) is a multi-tribe organization and this letter is in support of the Shiishongna Tongva Nation Corona Band of Gabrielino Indians (CCST Member) and their efforts to be added to the Native American Heritage contact list. Their objective is to protect the cultural resources of their ancestral communities by ensuring that they are included in the Native American Heritage Commission list. I have been fortunate to work together with them in the past, through the River side Unified School District, Native American & Indigenous Education Coalition through the California Native Vote Project, and our efforts to have Native history taught in schools across California with the passing of proposition AB 1703 (The CA Indian Education Act - Ramos).

Shiishongna Tongva Nation Corona Band of Gabrielino Indians have been big supporters of the ongoing work of the California Coalition of State Tribes n the fight for Sovereignty and Self Determination.

The leadership and cultural influence the have shown for the betterment of all California Indian Communities are truly invaluable.

Feel free to reach me at 916-709-5494 or by email at: [email protected]

Thank you so much!

Joey Williams
President
Coalition of California State Tribes

Member Tribes:

President
Coalition of CA State Tribes:

Chalon Indian Nation
San Gabriel Band of Mission Indians- Gabrieleno/Tongva Gabrielino Tongva Indians of California
Kern Valley Indian Community
Fernandeno Tataviam Band of Mission Indians
Shiishonga Tongva Nation Band of Corona Indians
Nor Rel Muk Wintu Nation

Phone | (909) 799-7407
Fax | (909) 478-5501
25864-K Business Center Drive, Redlands, CA 92374
www.iercd.org
…The Quality of the Environment Determines the Quality of Life…

July 16th, 2024

Native American Heritage Commission (NAHC)
1550 Harbor Boulevard Suite 100
West Sacramento, California
95691

Re: Letter of Support for Shiishongna Tongva Nation Corona Band of Gabrielino Indians

To Whom It May Concern,

On behalf of the Board of Directors of the Inland Empire Resource Conservation District (IERCD), I honored today to be able to provide a letter of support on behalf of the Shiishongna Tongva Nation Corona Band of Gabrielino Indians. The IERCD is a public agency headquartered in Redlands but providing open space preservation, support for sustainable agriculture and forests, habitat uplift, and education and outreach within 1,286 square miles of the upper Santa Ana River watershed. Our service area includes ancestral lands sacred to the Shiishongna Tongva Nation Corona Band of Gabrielino Indians and through that connection, we have had the opportunity to work regularly with tribal members on issues currently or with significant potential to impact critical natural and cultural resources. It is my privilege today to write a letter of support on behalf of the work they are doing in the region, and provide IERCD’s strongest endorsement for full tribal recognition.

Over the last six years, the IERCD has worked with tribal members on both a 40-A historical property with rich cultural history and multiple areas in need of conservation work to return benefit to local communities and dependent species.

Tribal members have been extensively involved in project advancement, identifying areas of collaboration and priorities included in the site master plan, and becoming a partner on the property. Outside of this site, IERCD staff members have also worked extensively with tribal members on areas of significant cultural and resource protection need, primarily focused on the 13,000-year old Jurupa Oak. With the existence of the oldest organism in the state currently threatened by development plans, tribal members have sought to protect it through countless hours documenting its importance as a sacred cultural resource. Recent planning and participation in public meetings by tribal members was key in the city’s decision to table development plans until further assessment could be completed. The IERCD is grateful for the opportunity to note that hours of unpaid work by the Shiishongna Tongva Nation Corona Band of Gabrielino Indians played an integral role here, but has not been limited to just this project alone. Their commitment to conservation and cultural resources in the Inland Empire cannot be understated.

I am again honored today to be able to provide our full support through this letter to the Shiishongna Tongva Nation Corona Band of Gabrielino Indians. If you have any questions, please do not hesitate to contact me at (909) 855-6473 or [email protected]. Sincerely,

Mandy Parkes, District Manager
Inland Empire Resource Conservation District
909-855-6473
[email protected]

Docusign Envelope ID: EADC2DB5-F871-4BF5-9B3C-3F142C6A668D

Shiishonga Tongva Nation Corona Band of Gabrieleno Indians 5352 Peacock Lane Riverside, CA 92505 Re: The efforts to save the oldest living lifeform in California and the Shiishonga-Gabrieleno Indian's true role in the effort.

To whom it may concern,
July 28, 2024
The Shiishonga-Gabrieleno Band has recently been falsely denied as the true Gabrieleno/Kizh Indians representing the area of the City of Jurupa Valley where the oldest living lifeform in California is living. Despite the false claim against them, the Shiishonga are the true indigenous people of the lifeform's area. The oldest lifeform is an ancient Palmer's Oak tree. A 2009 article published by five Botanists (3 from UCR and 2 from UC Davis). They established with tree ring dating that the tree dates from 13,000 to 18,000 years old. The Jurupa Oak is the oldest lifeform in California, the oldest oak in the U.S., the oldest oak in the world and among the oldest living lifeforms in the world. As the Kizh Gabrieleno's Tribal Archaeologist, I started the effort to save the tree from a planned developer who if given final approval with its current devel opment plan will kill the unique oak. With the Tribe's approval, I nominated the tree as the "Kizh Sacred Hurungna Oak" in Riverside County, to the State of California's Native American Heritage Commission's Sacred Land's File and it and 40 acres around it was approved by the NAHC with the "NAHC Site Number: N-RIV-123" on 8/14/2018. The recent initial city's approval of the developer's plan (supported by a rogue Kizh Band so it can get as 250,000 bribe from the developer) calls for only a few hundred feet around the oak to save it which is grossly inadequate. All organizations supporting saving the Jurupa Oak, including virtually all other Gabrieleno Bands, the Sierra Club, the California Native Plant Society, the Center for Biological Research, etc. all support that the high hill on which the tree lives needs to be entirely preserved, as well as a large area below it, as a Nature Reserve, where the world's visitors can view the extra-ordinary tree, hopefully from a Visitors Center some day. The Shiishonga have been totaly supportive of the responsible efforts to save the tree in their cultural indigenous area. Truly yours, Dr, GaryStickel (Ph.D. UCLA), Kizh Tribal Archaeologist (626) 387-9978; [email protected] cC: Chairman Nick Rocha (of another Kizh/Gabrieleno Band); (626) 322-6840

July 12, 2024.

To Whom It May Concern,

As Lead Ranger of the North Etiwanda Preserve (NEP), I’ve had the opportunity to interface with Chief Michael Negrete of the Shiishongna Tongva Tribe and Nation Corona Band of Gabrielino Indians on multiple occasions.

During a recent visit he generously took the time to educate both myself and undergraduate students from Pitzer College of Claremont, CA. giving us invaluable insight on parts of our local indigenous cultural history and topics related to the NEP .

The information exchanged covered preservation threats, signiﬁcance of cultural/ecological values, and, last but not least, the protection of the White Sage within the protected ecosystem of the NEP .

Having the Shiishongna Tribe present reminded us that if we don’t know where we’ve come from, we won’t know where we’re going.

I truly appreciate the support of Chief Michael Negrete and his tribe members in furthering our education of its history and am looking forward to our continued partnership in the future.

Sincerely,

Ron Goodman
Lead Ranger/North Etiwanda Preserve

North Fork Mono Tribe
13396 Tollhouse Rd.

Clovis, CA 93619

July 16, 2024

To: Chief Michael Negrete
Shiishonga Tribe

Re: Tribal Partners

To Whom it Concerns:

As the Tribal Leader of the North Fork Mono Tribe, we recognize and collaborate with the Shiishonga tribal members on several fronts. We are both members of the state-wide CA State Recognized Tribes of California; both recognized members of the State of CA Heritage Commission.

This past couple of years, members of the Shiishonga, have engaged in various tribal events coordinated by the North Fork Mono Tribe, including a State-wide archaeological monitor certified training to help build their tribal capacity. Their tribal members have actively attended the NFMT Ceremonial Cultural Burn trainings in Mariposa.

The NFMT is one of the lead “trainers” of Cultural Burning, training numerous tribes, agencies (CalFire, USFS, Fed Parks, State Parks), state and national environmental organizations, colleges, Universities, etc. for over twenty years.

We have been conducting archaeological monitor training since 1991. Our training manual was developed by Janet Ediness and I, Ron Goode. I helped develop the NA monitor guidelines for the Heritage Commission in the mid-late 1980s.

On behalf the North Fork Mono Tribe, we recognize and support capacity efforts and endeavors promulgated by the Shiishonga Tribe, especially those improving and protecting Planet Earth and her resources.

Hon. Ron W. Goode

August 10, 2024 To Whom It May Concern: I am writing to urge you to engage in formal tribal consultation with Chief Michael Negrete and members of the Shiishongna Tongva Nation Corona Band of Gabrielino Indians for all land use projects in the Inland Valley region. The Shiishongna Tongva Nation is a central part of the Indigenous landscape of Southern California. Chief Michael (Mike) and Laura Jaime of the Shiishongna Tongva Nation have been core partners in educating and advocating on behalf of native plant landscapes, cultural practices, and in particular on behalf of the Jurupa Oak, which is considered sacred and their oldest living relative. Their presentations and discussions at our meetings have educated our broader group of advocates on the traditional practices, ceremonial importance, and cultural significance of Tongva people and the Jurupa Oak in particular. It is critical that the Shiishongna Tongva Nation Corona Band of Gabrielino Indians be formally consulted as a tribal group as required by the California Environmental Quality Act. Not to do so is to continue the legacy of colonialism, which has stripped all Tongva tribal groups of their federal recognition. It is particularly important to do so with this case, as this is the tribal group in closest geographical and historic proximity to the Jurupa Oak tree. Consulting and collaborating with the Shiishongna Tongva Nation at every opportunity ties their past into this land’s present and future, and to the health of the landscape we share. We at the Redford Conservancy are truly appreciative of the support Chief Mike and tribal members have given us, along with the information they have provided and continue to provide for our community and this land. We have worked with many tribal groups through the Conservancy’s and Pitzer’s history. The Shiisongna are unbelievably generous, welcoming, and dedicated to education and mutual support. We urge you to respect their longstanding history on this land by consulting them formally on this and other relevant land use projects in the area. If you have any additional questions, please feel free to reach out to me directly. Sincerely, Susan A. Phillips Director, Robert Redford Conservancy for Southern California Sustainability Associate Dean Professor of Environmental Analysis Pitzer College 323-899-7862 [email protected]

July 9, 2024
To Whom It May Concern,
Chief Michael Negrete of the Shiishongna Tribe and the Corona Band of Gabrielino Indians has been a vital resource to our community. Chief Michael (Mike) and several members of his tribe have attended and presented at our Wonders of the Watershed, Duck Daze, and Twilight Tails events, as well as our summer camp. Their presentations at these events have educated our local community, park patrons, campers, and students on the traditional practices, ceremonial songs, and cultural significance of the Native Tongva people. Hidden Valley Wildlife Area and Nature Center rest on native Tongva land. In honor of their historical presence, we have a replica of their traditional housing, a Kish, in our educational village. Unfortunately, the village has faced vandalism and natural overgrowth, causing months of closures. Chief Mike and his members stepped in to help clean, clear, and bless the village so it may return to its functioning purpose.

Having the Shiishongna Tribe present at every opportunity ties their past into this land’s present and future. We are truly appreciative of the support Chief Mike and his tribe members have provided and continue to provide for our community and this land.

If you have any additional questions, please feel free to reach out to me directly.

Best,

Bridget Lawlor, Ph.D.

Historic Preservation Officer

Twilight Tails Event, 2023

Village Clean Up, 2023

Appendix C. Mitigation Monitoring Plan No. 398

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Mitigation Monitoring Program No. 398
MMP No. 398 1 November 2025
OC River Walk Project
Mitigation Monitoring Program No. 398

1.1 Introduction

1.1.1 Purpose of Mitigation Monitoring Program
In accordance with the California Environmental Quality Act (CEQA), California Public Resources Code (PRC), Section 21000 et seq.), the City of Anaheim (City), prepared an Environmental Impact Report (EIR) No, 357 (State Clearinghouse No. 2023030639) for the OC River Walk Project (project) dated July 2025. The Mitigation Monitoring Program (MMP) No. 398 has been prepared in conformance with Section 21081.6 of the Public Resources Code. Section 21081.6 states:
(a) When making findings required by paragraph (1) of subdivision (a) of Section 21081 or when adopting a mitigated negative declaration pursuant to paragraph (2) of subdivision (c) of Section 21080, the following requirements shall apply:
(1) The public agency shall adopt a reporting or monitoring program for the changes made to the project or conditions of project approval, adopted in order to mitigate or avoid significant effects on the environment. The reporting or monitoring program shall be designed to ensure compliance during project implementation. For those changes which have been required or incorporated into the project at the request of a responsible agency or a public agency having jurisdiction by law over natural resources affected by the project, that agency shall, if so requested by the lead or responsible agency, prepare and submit a proposed reporting or monitoring program.
(2) The lead agency shall specify the location and custodian of the documents or other material which constitute the record of proceedings upon which its decision is based.

1.1.2 Environmental Impacts

1.1.2.1 Impacts Considered No Impact or Less Than Significant An Initial Study for the project was prepared during the Notice of Preparation process. The Initial Study, dated March 2023, determined that the following environmental resources would have a less- than-significant impact or no impact:

No Impact
• Aesthetics: Thresholds a, b, and c.
• Agriculture and Forestry Resources: Thresholds a through c.

Mitigation Monitoring Program No. 398
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OC River Walk Project
• Air Quality: Threshold a.
• Biological Resources: Thresholds e and f.
• Cultural Resources: Threshold c.
• Energy: Threshold b.
• Greenhouse Gas Emissions: Threshold b.
• Hazards and Hazardous Materials: Thresholds c and e.
• Land Use and Planning: Thresholds a and b.
• Mineral Resources: Thresholds and b.
• Noise: Threshold c.
• Population and Housing: Thresholds a and b.
• Transportation: Threshold d.
• Wildfire: Thresholds a through d.

Less Than Significant
• Aesthetics: Threshold d.
• Air Quality: Threshold b, c, and d.
• Energy: Threshold a.
• Geology and Soils: Threshold e and f.
• Greenhouse Gas Emissions: Threshold a.
• Hazards and Hazardous Materials: Threshold a, f, and g. • Hydrology and Water Quality: Thresholds b and e.
• Public Services: Thresholds a.i, a.ii, a.iii, a.iv, and a.v. • Recreation: Threshold a and b.
• Transportation: Thresholds a and c.
• Utilities and Service Systems: Thresholds a, b, c, d, and e.

Mitigation Monitoring Program No. 398
MMP No. 398 3 November 2025
OC River Walk Project
The EIR identified various thresholds from the CEQA Guidelines across multiple environmental categories that would not be significantly impacted by the project, as discussed in Chapter 4, Environmental Analysis. Therefore, these topics did not require mitigation. Impacts to the following environmental resources were found to be less than significant or to have no impact:

No Impact
• Cultural Resources: Threshold CUL-1.

Less Than Significant
• Air Quality: Thresholds AQ-2, AQ-3, and AQ-4.
• Biological Resources: Threshold BIO-4.
• Cultural Resources: Threshold CUL-2.
• Geology and Soils: Thresholds GEO-1.i, GEO-1.ii, GEO-1.iii, GEO-1.iv, GEO-2, GEO-3, GEO-4. • Greenhouse Gas Emissions: Threshold GHG-1.
• Hazards and Hazardous Materials: Thresholds HAZ-2 and HAZ-4. • Hydrology and Water Quality: Threshold HYD-3a, HYD-3b and 3d, HYD-3c (Drainage Capacity), HYD-4, and HYD-5.
• Transportation: Threshold T-2.

Potentially Significant Adverse Impacts That Can Be Mitigated, Avoided, or Substantially Lessened
The EIR concluded that the proposed project could result in one or more potentially significant impacts in the following topic areas:
• Biological Resources: Thresholds BIO-1, BIO-2, and BIO-3. • Hydrology and Water Quality: Thresholds HYD-1 and HYD-3c (Polluted Runoff) • Noise: Thresholds NOI-1 and NOI-2.
• Tribal Cultural Resources: Threshold TCR-1
Unavoidable Significant Adverse Impacts
No significant and unavoidable adverse impacts were identified after implementation of required mitigation as identified in the EIR No. 357.

Mitigation Monitoring Program No. 398
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OC River Walk Project

1.2 Categorized Mitigation Measures/Matrix
Project-specific mitigation measures (MM) have been categorized in matrix format, as shown in Table 1, Mitigation Monitoring Requirements. The mitigation measures were included in the Draft EIR, with minor modifications in the Final EIR No. 357, and are applicable to the project. The matrix identifies the environmental factor, specific mitigation measures, schedule, and responsible monitor. The mitigation matrix will serve as the basis for scheduling the implementation of and compliance with all mitigation measures.

Mitigation Monitoring Program No. 398
MMP No. 398 5 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
Section 4.2, Biological Resources
BIO-1: Qualified Monitoring Biologist. Before the start of construction activities, the City of Anaheim project manager (or designee) shall retain a qualified monitoring biologist to implement required monitoring and document the names and resumes of the people involved in the biological monitoring of the project and a schedule for the proposed work.

The qualified monitoring biologist shall be responsible for the following monitoring and reporting tasks:
• Biological Construction Mitigation/Monitoring Exhibit. Before the start of construction within the future site-specific proposed survey area, the qualified monitoring biologist shall submit a Biological Construction Mitigation/Monitoring Exhibit, which includes limits of work, proposed monitoring schedule, bird, focused sensitive species, or other wildlife surveys/survey schedules (including general avian nesting and U.S. Fish and Wildlife Service protocol), timing of surveys, bird construction avoidance areas/noise buffers/barriers, other impact avoidance areas, and any subsequent requirements determined by the qualified monitoring biologist. The Biological Construction Mitigation/Monitoring Exhibit shall include the construction site plan, written and graphic depiction of the project’s biological mitigation/monitoring program, and a schedule for construction activities. Where the potential for impacts to biological resources is limited (e.g., construction within a footprint that consists entirely of previously developed or disturbed lands), the Biological Construction Mitigation/Monitoring Exhibit may be limited to a pre- and post-maintenance verification inspection. For highly sensitive resource areas, full-time biological monitors may be required. The Biological Construction Mitigation/Monitoring Exhibit shall be approved by the City of Anaheim project manager (or designee) before the start of construction.

City of Anaheim
project manager
(or their designee)
and Project
Biologist
Before the start of
construction
activities;
Before the
issuance of
any permit to
allow for the
removal or
demolition of
trees on the
project site
Community
Services
Department,
Parks Division

Mitigation Monitoring Program No. 398
MMP No. 398 6 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
• Avian Protection. To avoid any direct impacts to raptors and/or any migratory birds protected under the Migratory Bird Treaty Act, removal of habitat that supports active nests on the proposed area of disturbance should occur outside the breeding season for these species (January 15 to August 31). If removal of habitat on the proposed area of disturbance must occur during the breeding season, the monitoring biologist shall conduct a pre-construction survey to determine the presence or absence of nesting birds on the proposed area of disturbance. The pre-construction survey must be conducted within 10 calendar days before the start of construction, the results of which must be submitted to the City of Anaheim project manager (or designee) for review and approval before initiating any construction activities. If nesting birds are detected, a letter report or mitigation plan as deemed appropriate by the City of Anaheim shall be prepared and include proposed measures to be implemented to ensure that disturbance of raptor and bird breeding activities are avoided. The report or mitigation plan shall be submitted to the City of Anaheim for review and approval and implemented to the satisfaction of the City of Anaheim. The monitoring biologist shall verify and approve that all measures identified in the report or mitigation plan are in place prior to and/or during construction.
• Resource Marking/Protection. Prior to the start of construction activities within the future site-specific proposed survey area, the qualified monitoring biologist shall supervise the placement of orange construction fencing or similar visible marker, staking, or flagging along the limits of the construction area, particularly where adjacent to sensitive biological avoidance areas, as shown on the Biological Construction Mitigation/Monitoring Exhibit to ensure crews remain within the approved construction limits. These demarcations shall not be required for areas with existing barriers, such as chain-link fencing, along the limits or facilities that are within and/or adjacent to developed and non-sensitive habitat areas. This task shall include Mitigation Monitoring Program No. 398
MMP No. 398 7 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
flagging plant specimens and delineating buffers to protect sensitive biological resources (e.g., habitats, sensitive plant and wildlife species, including nesting birds) prior to construction. • Cover Trenches. The qualified monitoring biologist shall oversee the construction site so that cover and/or escape routes for wildlife from excavated areas shall be provided daily. Steep trenches, holes, and excavations during construction shall be covered at night with backfill, plywood, metal plates, or other means, and if plastic sheeting is used, the edges must be covered with soils such that small wildlife cannot access the excavated hole. Soil piles shall be covered at night to prevent wildlife from burrowing in. Sandbags shall weigh down the edges of the sheeting. These areas may also be fenced to prevent wildlife from gaining access. Exposed trenches, holes, and excavations shall be inspected twice daily (i.e., each morning and before sealing the exposed area) by the qualified monitoring biologist to monitor for wildlife entrapment. Excavations shall provide an earthen ramp to allow for a wildlife escape route. The qualified monitoring biologist shall verify that the contractor has covered all steep-walled trenches or excavations prior to the end of construction daily. If wildlife species are encountered within any trenches or excavated areas, the qualified monitoring biologist shall remove them, if possible, or provide them with a means of escape (e.g., a ramp or sloped surface at no greater than a 30-degree angle) and allow the species to disperse. In addition, the qualified monitoring biologist shall train construction personnel to increase awareness of the possible presence of wildlife beneath vehicles and equipment and to use best judgment to avoid killing or injuring wildlife (refer to Pre-Construction Meeting/Education).
• Structure Clearance. Before the issuance of any permit to allow for the removal or demolition of trees on the project site (particularly any ornamental trees in the developed land areas), the qualified Mitigation Monitoring Program No. 398
MMP No. 398 8 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
monitoring biologist shall conduct clearance surveys to flush out any wildlife species nesting, roosting, or otherwise occupying the trees. If wildlife species are encountered within any of the trees (outside the general bird nesting season), the qualified monitoring biologist shall remove them, if possible, or provide them with a means of escape and allow the species to disperse. If tree-roosting bats are suspected, slow removal by gently pushing the tree over with heavy equipment is required.
• Pre-Construction Meeting/Education. Before the start of any construction activity where the site plan for the construction area indicates that significant impacts to biological resources may occur, a pre-construction meeting shall be held on site with the following in attendance: City of Anaheim project manager (or designee), the construction contractor (if applicable), and the qualified monitoring biologist. At this meeting, the qualified monitoring biologist shall identify and discuss the construction protocols that apply to the proposed activities and the sensitive nature of the adjacent habitat with appropriate project personnel.

At the pre-construction meeting, the qualified monitoring biologist shall submit to the construction contractor a copy of the Biological Construction Mitigation/Monitoring Exhibit that identifies areas to be protected, fenced, and monitored. This data shall include all buffer limits, if applicable.

Before the start of construction activities, the qualified monitoring biologist shall meet with the construction contractor and crew and conduct an on-site educational session regarding the need to avoid impacts outside the approved construction footprint and to protect sensitive plants and wildlife that may occur at the specific facility. This may include but not be limited to explanations of the avian and aquatic resource buffers, the flag system for retention of sensitive Mitigation Monitoring Program No. 398
MMP No. 398 9 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
plants, and clarification of acceptable access routes/methods and staging areas.
• Biological Monitoring and Reporting. The qualified monitoring biologist shall inspect/monitor the project construction area in accordance with the approved Biological Construction
Mitigation/Monitoring Exhibit. This may be limited to pre- and post- maintenance inspections, weekly visits, or full-time monitoring, as determined by the qualified monitoring biologist.

The qualified monitoring biologist shall document monitoring events via a Consultant Site Visit Record. This record shall be sent to the project manager each month. However, if weekly reports are submitted as part of a separate agency permit requirement, these reports may be forwarded to the project manager in place of Consultant Site Visit Record submittals.

If no deviations from the construction site plan occur during maintenance, no additional documentation is required. However, if deviations from the site plan do occur, such as unanticipated impacts to sensitive vegetation communities or unanticipated discharge of pollutants, a Final Monitoring Report shall be prepared within 3 months following the completion of mitigation monitoring detailing maintenance and monitoring that occurred and any remedial or compensatory measures taken.

BIO-2: Sensitive Vegetation Communities and Jurisdictional Aquatic Resources Impacts Mitigation. Any direct impacts to sensitive vegetation communities or jurisdictional aquatic resources would require mitigation to comply with state and/or federal authorizations in accordance with the minimum ratios described in the following table and the ratios defined in any state and/or federal permit(s) issued for the project.

City of Anaheim
project manager
(or their designee)
and Project
Biologist;

Before the start of
construction
activities
Community
Services
Department,
Parks Division;
California
Department of
Fish and
Wildlife;
Regional Water

Mitigation Monitoring Program No. 398
MMP No. 398 10 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
Mitigation Ratios for Potential Impacts to Sensitive Vegetation Communities and Jurisdictional Aquatic Resources
Vegetation Community Jurisdiction
Minimum Mitigation
Ratio
Fresh Water USACE/RWQCB/CDFW 2:1
Freshwater Emergent
Wetland
USACE/RWQCB/CDFW 2:1
Non-Vegetated Channel USACE/RWQCB/CDFW 2:1
Diegan Coastal Sage
Scrub
CDFW 2:1
Mule Fat Scrub (Disturbed) CDFW 2:1
Southern Willow Scrub USACE/RWQCB/CDFW 2:1
Notes: CDFW = California Department of Fish and Wildlife; RWQCB = Regional Water Quality Control Board; USACE = U.S. Army Corps of Engineers
• Potential direct impacts to sensitive vegetation communities, including jurisdictional aquatic resources, resulting from project implementation shall be mitigated through one of the following two options:
− Project compensatory mitigation for proposed impacts to sensitive vegetation communities, including jurisdictional aquatic resources, shall be provided through in-kind and on-site creation, enhancement, and/or restoration. A Habitat Mitigation and Monitoring Plan shall be provided and prepared in accordance with the City of Anaheim and regulatory agency requirements. − Compensatory mitigation requirements that are not able to be satisfied through on-site creation, enhancement, and/or restoration shall be satisfied through the acquisition of mitigation bank credits via a resource agency-approved mitigation site within the Santa Ana River Watershed or by acquisition of other approved off-site mitigation credits. Prior to implementation of project construction impacts that would require compensatory Quality Control
Board; U.S.

Army Corps of
Engineer
Mitigation Monitoring Program No. 398
MMP No. 398 11 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
mitigation, documentation demonstrating the availability of mitigation credits (i.e., credit ledger) at the approved mitigation site must be submitted to the City of Anaheim project manager (or designee) for confirmation.

When proposed mitigation involves habitat enhancement, restoration, or creation, the Habitat Mitigation and Monitoring Plan shall include the following information:
• Conceptual planting plan including planting zones, grading, and irrigation.
• Seed mix/planting palette.
• Planting specifications.
• Monitoring program including success criteria.
• Long-term maintenance and preservation plan.

For mitigation that involves habitat acquisition, the Habitat Mitigation and Monitoring Plan shall include the following:
• Location of proposed acquisition.
• Description of the biological resources to be acquired, including support for the conclusion that the acquired habitat mitigates for the specific maintenance impact and satisfies the requirement of no net loss.
• Documentation that the mitigation area would be adequately preserved and maintained in perpetuity.

The identification of mitigation site credits shall be provided to the City of Anaheim project manager (or designee) and shall include the following:
• Location of approved mitigation site.
• Description of the mitigation credits to be acquired, including support for the conclusion that the acquired habitat mitigates for the specific maintenance impact and satisfies the requirement of no net loss.

Mitigation Monitoring Program No. 398
MMP No. 398 12 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
• Documentation of the credits that are associated with a mitigation bank, which has been approved by the appropriate resource agencies.
• Documentation in the form of a current mitigation credit ledger.

BIO-3: Habitat Restoration in Temporary Impact Areas. Temporary direct impact areas shall be restored to pre-construction topographic contours and conditions, including the revegetation of native plant communities, where appropriate. Habitat restoration and erosion control treatments shall be installed within these short-term impact areas. Habitat revegetation shall feature native species that are typical of the area, and associated erosion control best management practices shall include silt fence and microplastic- and weed-free straw fiber rolls, where appropriate. The revegetation areas shall be monitored and maintained for 25 months to ensure adequate establishment and sustainability of the plantings/seedings.

Where a project activity involves potential disturbance of non-native invasive plant species (as identified by the California Invasive Plant Council), these plants shall be entirely removed where feasible, and the removal shall be monitored by the qualified monitoring biologist to ensure that dispersal of propagules (e.g., seeds, stems, etc.) are avoided or minimized. Where removal of plant roots is not feasible (e.g., where erosive flows are predicted), aboveground plant material shall be fully removed and monitored by the qualified monitoring biologist. Where aboveground plant material cannot be removed (e.g., due to limited access), herbicides shall be applied by a licensed pest control advisor, using chemicals permitted as safe within aquatic environments.

City of Anaheim
project manager
(or their designee)
and Project
Biologist

Post-construction Community
Services
Department,
Parks Division
Construction
contractor and
Project
Biologist

Mitigation Monitoring Program No. 398
MMP No. 398 13 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
BIO-4: Least Bell’s Vireo and Yellow Warbler Pre-Construction Surveys. For any work proposed in or near suitable habitat between February 15 and August 15 (March 15 and September 15 for least Bell’s vireo), a pre- construction survey for least Bell’s vireo and yellow warbler shall be performed to reaffirm the presence and extent of occupied habitat. The survey shall occur within five days prior to the start of construction. The pre-construction survey area for the species shall encompass all potentially suitable habitat within the project work zone and a 300-foot survey buffer.

The pre construction survey shall be performed to the satisfaction of the City of Anaheim project manager (or their designee) by a qualified biologist familiar with the species. The results of the pre-construction survey shall be submitted in a report to the City of Anaheim project manager (or their designee) for review and approval before initiating any construction activities. If least Bell’s vireo or yellow warbler are detected, a minimum 300-foot buffer delineated by orange biological fencing shall be established around the detected species. In addition, on-site noise reduction/attenuation techniques shall be incorporated, as appropriate, to avoid impacts to breeding least Bell’s vireo and yellow warbler from elevated construction noise levels during the breeding season. The City of Anaheim project manager (or their designee) shall have the discretion to modify the buffer width depending on site-specific conditions. In addition, noise monitoring may be required to ensure that the elevated construction noise levels are appropriately attenuated at the edge of occupied habitat to a level that is not expected to adversely affect nesting bird behavior (i.e., not to exceed an hourly average of 60 A-weighted decibels or ambient whichever is greater, at the edge of occupied habitat).

City of Anaheim
project manager
(or their designee)
and Project
Biologist, Qualified
noise consultant

Within 5 days
prior to the
start of
construction
Community
Services
Department,
Parks Division

Mitigation Monitoring Program No. 398
MMP No. 398 14 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
Section 4.7, Hydrology and Water Quality
HYD-1: Prior to the issuance of a discretionary and/or regulatory permit by the City of Orange, County of Orange, or Orange County Water District (“Participating Stakeholders”), the City of Anaheim shall enter into a Maintenance and Operations Agreement (MOA) with the Participating Stakeholder issuing said permit, as applicable. The MOA shall specify roles, responsibilities, performance standards, and communication protocols for the ongoing maintenance and operation of the project elements.

The MOA shall include, at a minimum, the following responsibilities and tasks, or similar, as appropriate for each agreement with the applicable agency:
• Maintenance responsibilities related to trails, river impoundments and water features, and stormwater and sewer facilities;
• Operations responsibilities related to access control, hours of operation, public use rules (including, but not limited to, posting signage for hours, allowed uses, and prohibited activities), security and public safety (including, but not limited to, law enforcement coordination, patrolling duties, transient management, and emergency response protocols), debris removal, preparation and implementation of a flood contingency plan, and post storm event procedures; • Inspection, monitoring, and reporting responsibilities, including the frequency of routine inspections and water quality monitoring as required by applicable regulatory permits and to address any public health concerns regarding recreational use of the water in the Santa Ana River channel; and
• Communication and notification protocols, including construction timing and phasing information for each project element.

The MOA shall include provisions granting the County of Orange (OC) agencies—including, but not limited to, OC Public Works, OC Parks, and City of Anaheim
project manager
(or their designee)
Prior to the
issuance of a
discretionary
and/or regulatory
permit by the City
of Orange,
County of
Orange, or
Orange County
Water District
Community
Services
Department, Parks
Division

Mitigation Monitoring Program No. 398
MMP No. 398 15 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
OC Sheriff’s Department—vehicular access for monitoring river flows, ensuring public safety, and performing other OC maintenance and operational activities currently conducted by OC agencies, including review and approval of trail improvements and access design. The MOA shall also address any other items deemed necessary by the Participating Stakeholders to ensure the proper long-term maintenance and operation of the project.

Section 4.8, Noise
NOI-1: The City of Anaheim shall include the following construction specifications on all project construction plans for sites located within 100 feet of sensitive receptors (i.e., Extended Stay America – Orange County hotel building and occupied residential buildings) or 60 feet of occupied office buildings.

During construction, the construction contractor shall employ the following noise-reducing measures where use of construction equipment occurs within 100 feet of sensitive receptors or 60 feet of occupied office buildings:
• Use acoustical shelters around any air compressors, generators, and any other stationary construction equipment not fitted with baffled enclosures
• Use baffling around stationary construction equipment to reduce noise and vibration levels
• Properly muffle and maintain all construction equipment powered by internal combustion engines
• Prohibit unnecessary idling of internal combustion engines • Whenever feasible, use electrical power to run air compressors and similar power tools
City of Anaheim
project manager (or
their designee)
Prior to and
during
construction
Community
Services
Department, Parks
Division

Mitigation Monitoring Program No. 398
MMP No. 398 16 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
NOI-2: The City of Anaheim shall ensure that all project construction specifications include the following noticing requirement. The construction contractor shall provide written notification at least 1 week prior to the start of any construction activities within 110 feet of sensitive receptors (i.e., Extended Stay America – Orange County hotel and occupied residential buildings) or 235 feet of the Kinder Morgan Orange Terminal. The notice shall inform hotel, occupied residential buildings, and industrial operators of the estimated start date and duration of daytime vibration-generating construction activities and provide a point of contact for vibration exposure complaints.

City of Anaheim
project manager (or
their designee)
Prior to
construction;
Prior to at least 1
week prior to the
start of any
construction
activities
Community
Services
Department, Parks
Division

Section 4.10, Tribal Cultural Resources
TCR-1: Prior to the commencement of ground-disturbing activities in any area where soil disturbance is greater than the depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet, and/or where there is documented resource presence, the City of Anaheim (lead agency) shall retain a single Native American Monitor at a time to monitor grading activities as described below.

If multiple Tribes have requested monitoring, a lead Native American Monitor shall be designated to serve as the primary monitor. Only one monitor shall be present on-site at any given time during grading activities, unless otherwise agreed upon by the lead agency and the designated lead Native American Monitor.

B. For the purposes of this requirement, “ground-disturbing activity” includes project locations inside the project boundary, excluding off- site work within existing public right-of-way. “Ground-disturbing activity” includes, but is not limited to, demolition, pavement removal, City of Anaheim
project manager (or
their designee); Native
American Monitor;
qualified archaeologist
Prior to the
commencement
of ground-
disturbing
activities
Community
Services
Department, Parks
Division

Mitigation Monitoring Program No. 398
MMP No. 398 17 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
potholing, auguring, grubbing, tree removal, boring, grading, excavation, drilling, and trenching resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet.

D. The Native American Monitor shall complete daily monitoring logs that will provide descriptions of the relevant ground-disturbing activities, the type of construction activities performed, locations of ground- disturbing activities, soil types, cultural-related materials, and any other facts, conditions, materials, or discoveries of significance to the Tribe and the lead agency. Monitor logs shall identify and describe any discovered Tribal Cultural Resources, including but not limited to Native American cultural and historical artifacts, remains, places of significance, etc., as well as any discovered Native American (ancestral) human remains and burial goods. Copies of monitor logs will be provided to the City and the Kizh and Acjachemen Tribes. Any other federally or state-recognized tribes requesting copies of the monitoring logs shall be provided with the logs by the City of Anaheim.

E. On-site Native American Monitor shall conclude upon the former of the following:
1) Written confirmation from a designated point of contact for the lead agency to the lead Native American Monitor that all ground- disturbing activities resulting in soil disturbance exceeding a depth of current foundations present on a project site, or in areas where the disturbance activities extend into native soils exceeding a depth of 5 feet on the project site or in connection with the project are complete; or
Mitigation Monitoring Program No. 398
MMP No. 398 18 November 2025
OC River Walk Project
Table 1. Mitigation Monitoring Requirements
Mitigation Measure
Responsible for
Implementation Timing
Responsible
for
Monitoring
Monitor
(Signature
Required)
(Date of
Compliance)
2) A determination and written notification from the lead Native American Monitor to the lead agency stating that no future planned construction or development activity at the project site has the potential to impact Kizh and Acjachemen Tribal Cultural Resources.

Appendix D. Revised Figures

T
his page intentionally left blank.

Source: OC River Walk Vision Plan 2024.

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1211

EXISTING ACTIVITIES, PROGRAMS AND

PEDESTRIAN USE ALONG THE RIVER
The OC River Walk runs through a variety of urban conditions including existing and proposed entertainment districts, low density commercial and industrial, and residential areas. A portion of the site runs through the Platinum Triangle district which includes Angel Stadium of Anaheim, Honda Center, and the City National Grove of Anaheim, each of which offer a myriad of organized and independent activities and programs along with mixed-use residential housing. Existing activities at the Honda Center and Angel Stadium of Anaheim include exhibitions, sporting events, and concerts. Activities along the River primarily include high-speed biking and offer opportunities for jogging, and dog walking.

PROJECT REACHES
Based on the project goals and objectives and the existing conditions, the project team has identified four design “reaches” across the site. Each reach was defined by the opportunities and constraints it presented relative to the project goals and objectives as they relate to the enhancement of active transportation, increasing river activation and interaction and providing community serving amenities.

Reach 1: Ball Road to Union Pacific Railroad
Reach 1 is the northern most reach and extends south from the Anaheim Coves Trail to the Union Pacific Railroad. It is characterized by the existing Santa Ana River Trail that runs along the east on top of the existing river embankment. An OCWD detention basin sits adjacent to the western bank. The western bank is classified as levee condition and has a maintenance road on top. There are two access ramps down to the riverbed that will remain and three pedestrian underpasses: two under Ball Road and one under the eastern side of the Union Pacific Railroad.

Future plans to infill the detention basin and develop it into high-density residential housing is under review by the City of Anaheim. Current right-of-way widths range from 12 feet to 32 feet. No stepped riverbank modifications are anticipated to occur along this reach. The proposed reach improvements are intended to connect the OC River Walk to the Anaheim Coves Trail and maintain a trail and recreation connection.

Reach 2: Union Pacific Railroad to Katella Avenue
Reach 2 is between the Union Pacific Railroad and Katella Avenue and is characterized by embankments on both the east and west banks. It is situated within an existing entertainment district, with a planned future mixed-use development and Honda Center on the City of Anaheim side and the Stadium Promenade shopping mall on the City of Orange side.

The Santa Ana River Trail crosses Katella Avenue and continues along the eastern bank adjacent to an extensive open space area owned by the OCFD that provides a right-of-way of nearly 200 feet. Portions of this area are currently fenced off. There are three existing underpasses that allow for uninterrupted bike and pedestrian access along the river with five outfalls located in this reach. There is one existing maintenance ramp leading down to the riverbed on the west bank to provide access below the drop structure. The right-of-way widths range from 18 feet to over 24 feet on the western bank and over 32 feet on the eastern bank. 75% of the reach will have water in the riverbed from the second impoundment structure. This reach provides significant opportunities to connect the Santa Ana River Trail to the Anaheim Coves Trail, improve connectivity of the Santa Ana River Trail by providing a new bicycle and pedestrian bridge, increase open space adjacent to the river, increase planting where possible, and improve river access.

Reach 3: Katella Avenue to ARTIC Station
Reach 3 is situated between Katella Avenue and the Los Angeles-San Diego-San Luis Obispo Rail Corridor (LOSSAN Corridor), a shared freight and passenger rail line that will be used in the future by the High-Speed Rail. The west bank can be characterized as civic with the ARTIC station and on the east bank its largely commercial and industrially zoned. Notable development on the east bank includes:
the Sandra Hutchens Regional Law Enforcement Training Center (a training facility that is home to a combat shooting range) as well as Orange County Public Works offices. The reach is characterized by embankments on east and west banks, with the west bank being classified as levee condition. The Santa Ana River Trail runs along the western bank with a maintenance path on the eastern bank. There are four existing underpasses that allow for continuous bike, pedestrian, and maintenance access. There are three outfalls and the confluence of Collins Channel, which is an existing channelized tributary. Because of the plans to develop the area in front of ARTIC into a future open space, there is significant opportunity to make a seamless connection between the OC River Walk and the future development to bring patrons to the river edge.

Reach 4: ARTIC Station to Orangewood Avenue
Reach 4 is the southernmost reach and is bound to the north by the LOSSAN rail corridor and to the south by Orangewood Avenue. An entertainment district is located on the west bank with the Angel Stadium of Anaheim and City National Grove of Anaheim. Opportunities for trail extension and connections exist on the eastern bank. State Route 57 bisects the Santa Ana River, creating a unique condition with significant shade and shelter. The existing right-of-way widths range from 18 feet to over 32 feet. A future public space developed by the City of Anaheim is proposed to abut the OC River Walk project and Angel Stadium of Anaheim. The eastern bank is significantly narrower in width and abuts industrial and commercial developments. Embankments exist on both sides of the river.

TOP OF BANK TOP OF BANK FUTURE

DEVELOPMENT

OVERFLOW

BASINSANTA ANA RIVER

SANTA ANA RIVER

SANTA ANA RIVER
SART
12’
0-15' 12’ 10' 12' 12' 12' 15' 12' 12'33'6'

SART SART

FUTURE DEVELOPMENTBUFFER BUFFER BUFFER

PATHBUFFER
BUFFER

BUFFER MAINTENANCE
PATH

MAINTENANCE
PATH
PATH
18’
30'-150'

IMPROVEMENT AREA
30'-150'

IMPROVEMENT AREA
REACH 1
REACH 3
12'-25'

IMPROVEMENT AREA
25'-50'

IMPROVEMENT AREA
35-150'

IMPROVEMENT AREA
12'

IMPROVEMENT AREA
12'-35'

IMPROVEMENT AREA
REACH 2
REACH 4

STADIUM PROMENADE STADIUM PROMENADE

ANGEL STADIUM

ANGEL STADIUM
57 FREEWAY
57 FREEWAY
57 FREEWAY

LOSSAN RAIL CORRIDOR

KA TELLA AVE

ARTIC STATION

ORANGEWOOD AVE

ARTIC STATION

COLLINS CHANNEL

HONDA CENTER

PROJECT SITE

PROJECT SITE
FUTURE

DEVELOPMENT
FUTURE

DEVELOPMENT

UNION PACIFIC RR
BUFFER
18’12'-35' 12’-35'
SART
12’
KATELLA AVE.

HONDA
CENTER

STADIUM

PROMENADE
ARTIC
ANGEL

STADIUM
OF

ANAHEIM

LO S S A N R A I L C O R R I D O R

ORANGEWOOD AVE

COLLINS CHANNEL

PROJECT BOUNDARY

UNION PACIFIC RR

B A L L R O A D
A N A

R I V E R

S A N T A
REACH 1REACH 2REACH 3REACH 4
700'
North
57 ANAHEIM
COVES
1 2
3 4
Source: OC River Walk Vision Plan 2024.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
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OC River Walk
N
OC RIVER WALK CONCEPTUAL MASTER PLAN 2024OC RIVER WALK CONCEPTUAL MASTER PLAN 2024 I. Introduction II. Design Approach III. River Reaches IV. Supplemental Information
1211

EXISTING ACTIVITIES, PROGRAMS AND

TOP OF BANK TOP OF BANK FUTURE

DEVELOPMENT

OVERFLOW

BASINSANTA ANA RIVER

SANTA ANA RIVER

SANTA ANA RIVER
SART
12’
0-15' 12’ 10' 12' 12' 12' 15' 12' 12'33'6'

SART SART

FUTURE DEVELOPMENTBUFFER BUFFER BUFFER

PATHBUFFER
BUFFER

BUFFER MAINTENANCE
PATH

MAINTENANCE
PATH
PATH
18’
30'-150'

IMPROVEMENT AREA
30'-150'

IMPROVEMENT AREA
REACH 1
REACH 3
12'-25'

IMPROVEMENT AREA
25'-50'

IMPROVEMENT AREA
35-150'

IMPROVEMENT AREA
12'

IMPROVEMENT AREA
12'-35'

IMPROVEMENT AREA
REACH 2
REACH 4

STADIUM PROMENADE STADIUM PROMENADE

ANGEL STADIUM

ANGEL STADIUM
57 FREEWAY
57 FREEWAY
57 FREEWAY

LOSSAN RAIL CORRIDOR

KA TELLA AVE

ARTIC STATION

ORANGEWOOD AVE

ARTIC STATION

COLLINS CHANNEL

HONDA CENTER

PROJECT SITE

PROJECT SITE
FUTURE

DEVELOPMENT
FUTURE

DEVELOPMENT

UNION PACIFIC RR
BUFFER
18’12'-35' 12’-35'
SART
12’
KATELLA AVE.

HONDA
CENTER

STADIUM

PROMENADE
ARTIC
ANGEL

STADIUM
OF

ANAHEIM

LO S S A N R A I L C O R R I D O R

ORANGEWOOD AVE

COLLINS CHANNEL

PROJECT BOUNDARY

UNION PACIFIC RR

B A L L R O A D
A N A

R I V E R

S A N T A
REACH 1REACH 2REACH 3REACH 4
700'
North
57 ANAHEIM
COVES
1 2
3 4
Source: OC River Walk Vision Plan 2024.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
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OC River Walk
N
OC RIVER WALK CONCEPTUAL MASTER PLAN 2024OC RIVER WALK CONCEPTUAL MASTER PLAN 2024 I. Introduction II. Design Approach III. River Reaches IV. Supplemental Information
1211

EXISTING ACTIVITIES, PROGRAMS AND

TOP OF BANK TOP OF BANK FUTURE

DEVELOPMENT

OVERFLOW

BASINSANTA ANA RIVER

SANTA ANA RIVER

SANTA ANA RIVER
SART
12’
0-15' 12’ 10' 12' 12' 12' 15' 12' 12'33'6'

SART SART

FUTURE DEVELOPMENTBUFFER BUFFER BUFFER

PATHBUFFER
BUFFER

BUFFER MAINTENANCE
PATH

MAINTENANCE
PATH
PATH
18’
30'-150'

IMPROVEMENT AREA
30'-150'

IMPROVEMENT AREA
REACH 1
REACH 3
12'-25'

IMPROVEMENT AREA
25'-50'

IMPROVEMENT AREA
35-150'

IMPROVEMENT AREA
12'

IMPROVEMENT AREA
12'-35'

IMPROVEMENT AREA
REACH 2
REACH 4

STADIUM PROMENADE STADIUM PROMENADE

ANGEL STADIUM

ANGEL STADIUM
57 FREEWAY
57 FREEWAY
57 FREEWAY

LOSSAN RAIL CORRIDOR

KA TELLA AVE

ARTIC STATION

ORANGEWOOD AVE

ARTIC STATION

COLLINS CHANNEL

HONDA CENTER

PROJECT SITE

PROJECT SITE
FUTURE

DEVELOPMENT
FUTURE

DEVELOPMENT

UNION PACIFIC RR
BUFFER
18’12'-35' 12’-35'
SART
12’
KATELLA AVE.

HONDA
CENTER

STADIUM

PROMENADE
ARTIC
ANGEL

STADIUM
OF

ANAHEIM

LO S S A N R A I L C O R R I D O R

ORANGEWOOD AVE

COLLINS CHANNEL

PROJECT BOUNDARY

UNION PACIFIC RR

B A L L R O A D
A N A

R I V E R

S A N T A
REACH 1REACH 2REACH 3REACH 4
700'
North
57 ANAHEIM
COVES
1 2
3 4
Source: OC River Walk Vision Plan 2024.

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N
OC RIVER WALK CONCEPTUAL MASTER PLAN 2024OC RIVER WALK CONCEPTUAL MASTER PLAN 2024 I. Introduction II. Design Approach III. River Reaches IV. Supplemental Information
1211

EXISTING ACTIVITIES, PROGRAMS AND

TOP OF BANK TOP OF BANK FUTURE

DEVELOPMENT

OVERFLOW

BASINSANTA ANA RIVER

SANTA ANA RIVER

SANTA ANA RIVER
SART
12’
0-15' 12’ 10' 12' 12' 12' 15' 12' 12' 33'6'

SART SART

FUTURE DEVELOPMENTBUFFER BUFFER BUFFER

PATHBUFFER
BUFFER

BUFFER MAINTENANCE
PATH

MAINTENANCE
PATH
PATH
18’
30'-150'

IMPROVEMENT AREA
30'-150'

IMPROVEMENT AREA
REACH 1
REACH 3
12'-25'

IMPROVEMENT AREA
25'-50'

IMPROVEMENT AREA
35-150'

IMPROVEMENT AREA
12'

IMPROVEMENT AREA
12'-35'

IMPROVEMENT AREA
REACH 2
REACH 4

STADIUM PROMENADE STADIUM PROMENADE

ANGEL STADIUM

ANGEL STADIUM
57 FREEWAY
57 FREEWAY
57 FREEWAY

LOSSAN RAIL CORRIDOR

KA TELLA AVE

ARTIC STATION

ORANGEWOOD AVE

ARTIC STATION

COLLINS CHANNEL

HONDA CENTER

PROJECT SITE

PROJECT SITE
FUTURE

DEVELOPMENT
FUTURE

DEVELOPMENT

UNION PACIFIC RR
BUFFER
18’12'-35' 12’-35'
SART
12’
KATELLA AVE.

HONDA
CENTER

STADIUM

PROMENADE
ARTIC
ANGEL

STADIUM
OF

ANAHEIM

LO S S A N R A I L C O R R I D O R

ORANGEWOOD AVE

COLLINS CHANNEL

PROJECT BOUNDARY

UNION PACIFIC RR

B A L L R O A D
A N A

R I V E R

S A N T A
REACH 1REACH 2REACH 3REACH 4
700'
North
57 ANAHEIM
COVES
1 2
3 4
Source: Pacific Advanced Civil Engineering, Inc. (PACE).

Katella Ave
Ball Rd
Or
ang
ewo
od A
ve
Eckhoff St
Collins Ave
Main St
Taft Ave
UPRR
Metrolink RR
57 FWY
Douglas Rd
Phoenix Club Dr
Auto Center Dr
Cerritos Ave
Anaheim
Orange
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
SD
CH
SD
SD
SD
SD
SD
SD
Storm Drain
Outlet
Existing Access
Ramp
Proposed Access
Ramp
Proposed
Impoundment
Proposed
Inflatable Rubber
Dam
OC River Walk
Trail
Improvements
Proposed Ped./
Bike Bridge
Proposed RR
Undercrossings
Proposed Kayak
Access (Maintain
Existing OCFCD
Access)
Existing
Undercrossing
Existing Storm
Drain
Existing Drop
Structure
City Boundary
Angel
Stadium
ARTIC Stadium
Promenade
Honda
Center
Arena
Corporate
Center
Collins Channel
Islands
Golf
Center
Burris
Basin
OC Sheriff's
Dept
OC Public
Works
Santa Ana River
Santa Ana River
Kinder Morgan
Orange Terminal
SD
C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
0 1200600 Figure 2-7
Proposed Impoundments and Trail Improvements
OC River Walk
N

Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8a
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B
(F)
Market &Office(F)
Concert
Hall
(F)
The
Steps(F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C(F)
Hotel (E)
Parking
Deck A (F)
Honda
Center
(Existing)
ARTIC
(E)
Existing
DropStructure
Existing
DropStructure
Angel
Stadium(E)

STADIUM

PROMENADE

KINDER MORGAN

ORANGE TERMINAL

COUNTY OF
ORANGE

OC PUBLIC
WORKS
OC SHERIFF'SDEPT.
(E)
City of Anaheim - Future Park
Future Open SpaceMeadow Park
Ex. Anaheim
Coves Trail
Future River Road
Stanley Cup Way
Cerritos Ave
Ball Rd
Katella Ave
Futurue
Neighborhood
Park
Future
Development
1d,e
6b
2 3
6a
1a, b
1g,h,i
6b
3 3
4 5e,g
5h
5f,g
5a,b 5c
5a,b
5a,b
5c
5a,b
5a,b
5e,g 5e,g,h
5e,g,h
5e,g
5e,g
5a,b
1f
1c
6a
5a,b
5e,g6b
6a
6b
6a
S P

ISLANDS GOLF

CENTER (E)
BURRIS

BASIN (E)
Metrolink RR
(MEADOW PARK)

1. Project element encompasses entire project area or is not specifically located at this time Note: All project locations are approximate
1a North Impoundment and Inflatable Rubber Dam 5a Anaheim - Storm Drain Outlets w/ Flap Gates 1b North Impoundment - Rubber Dam Concrete Foundation 5b Anaheim - Diversion Manholes 1c North Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5c Anaheim - Diversion Pump Stations 1d South Impoundment 5d Anaheim - Storm Drain Diversion Pipe to Sewer 1e South Impoundment - Rubber Dam Concrete Foundation 5e Orange - Storm Drain Outlets w/ Flap Gates 1f South Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5f Orange - In-Channel Diversion Structure at Collins Channel 1g Collins Channel - Inflatable Rubber Dam 5g Orange - Diversion Manholes 1h Collins Channel - Rubber Dam Concrete Foundation 5h Orange - Diversion Pump Stations 1i Collins Channel - Rubber Dam Air Compressor and Controls 5i Orange - Storm Drain Diversion Pipe to Sewer 5j Wet Weather Storm Drain Diversion to Impoundments*
6a North Impoundment Embankment
6b South Impoundment Embankment

2. Impoundment Evacuation Pumps

3. Pipeline from Pump Station to GWRS Turnout - N. of Orangewood to Burris Basin

4. GWRS Turnout - Concrete flow control structure with dechlorination facilities. Located at south end of Burris Basin - Offsite Project Element

GROUP A - IMPOUNDMENTS, EMBANKMENTS, & STORM DRAIN DIVERSIONS

1. Impoundments 5. Storm Drain Diversions (Dry Weather Flow)

6. River Embankments
1a North Impoundment and Inflatable Rubber Dam 5a Anaheim - Storm Drain Outlets w/ Flap Gates 1b North Impoundment - Rubber Dam Concrete Foundation 5b Anaheim - Diversion Manholes 1c North Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5c Anaheim - Diversion Pump Stations 1d South Impoundment 5d Anaheim - Storm Drain Diversion Pipe to Sewer 1e South Impoundment - Rubber Dam Concrete Foundation 5e Orange - Storm Drain Outlets w/ Flap Gates 1f South Impoundment - Rubber Dam Air Compressor, Controls, and Flow Bypass 5f Orange - In-Channel Diversion Structure at Collins Channel 1g Collins Channel - Inflatable Rubber Dam 5g Orange - Diversion Manholes 1h Collins Channel - Rubber Dam Concrete Foundation 5h Orange - Diversion Pump Stations 1i Collins Channel - Rubber Dam Air Compressor and Controls 5i Orange - Storm Drain Diversion Pipe to Sewer 5j Wet Weather Storm Drain Diversion to Impoundments¹
6a North Impoundment Embankment
6b South Impoundment Embankment

2. Impoundment Evacuation Pumps

3. Pipeline from Pump Station to GWRS Turnout - N. of Orangewood to Burris Basin

4. GWRS Turnout - Concrete flow control structure with dechlorination facilities. Located at south end of Burris Basin - Offsite Project Element

GROUP A - IMPOUNDMENTS, EMBANKMENTS, & STORM DRAIN DIVERSIONS

1. Impoundments 5. Storm Drain Diversions (Dry Weather Flow)

6. River Embankments
and Inflatable Rubber Dam
Approved City Park Space
(Not a Part)
Potential Future Park Area
Enhanced Recreational
Facilities (per Master Plan)
Proposed GWRS Turnout
Structure
Inflatable Rubber Dam &
River Impoundment
Trail Undercrossing
Retaining Wall
Embankment Improvements
OC River Walk Trail
Improvements

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout
PSS P
Proposed Improvements - Group A
OC River Walk
Feet
0 1000500N
Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8b
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B
(F)
Market &Office(F)
Concert
Hall
(F)
The
Steps(F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C(F)
Hotel (E)
Parking
Deck A (F)
Honda
Center
(Existing)
ARTIC
(E)
Existing
DropStructure
Existing
DropStructure
Angel
Stadium(E)

STADIUM

PROMENADE

KINDER MORGAN

ORANGE TERMINAL

COUNTY OF
ORANGE

OC PUBLIC
WORKS
OC SHERIFF'SDEPT.
(E)
City of Anaheim - Future Park
Future Open SpaceMeadow Park
Ex. Anaheim
Coves Trail
Future River Road
Stanley Cup Way
Cerritos Ave
Katella Ave
Futurue
Neighborhood
Park
Future
Development
2 1
3a
3b
3c
Ball Rd
S P

ISLANDS GOLF

CENTER (E)
BURRIS

BASIN (E)
(MEADOW PARK)
Metrolink RR
Note: All project locations are approximate
Approved City Park Space
(Not a Part)
Potential Future Park Area
Enhanced Recreational
Facilities (per Master Plan)
Proposed GWRS Turnout
Structure
Inflatable Rubber Dam &
River Impoundment
Trail Undercrossing
Retaining Wall
Embankment Improvements
OC River Walk Trail
Improvements

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout
PSS P
3a New Ped./Bike Bridge N. of Katella West Bank Retaining Wall #1 3b New Ped./Bike Bridge N. of Katella West Bank Retaining Wall #2 3c New Ped./Bike Bridge N. of Katella East Bank Retaining Wall #3

2. Ped./Bike Bridge N. of Orangewood

3. Bridge Retaining Walls

GROUP B - NEW PEDESTRIAN/BIKE BRIDGES

1. Ped./Bike Bridge N. of Katella
Proposed Improvements - Group B
OC River Walk
Feet
0 1000500N
Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8c
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B
(F)
Market &Office(F)
Concert
Hall
(F)
The
Steps(F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C(F)
Hotel (E)
Parking
Deck A (F)
Honda
Center
(Existing)
ARTIC
(E)
Existing
DropStructure
Existing
DropStructure
Angel
Stadium(E)

STADIUM

PROMENADE

KINDER MORGAN

ORANGE TERMINAL

COUNTY OF
ORANGE

ISLANDS GOLF

CENTER (E)
BURRIS

BASIN (E)
(MEADOW PARK)
Metrolink RR

1. Project element encompasses entire project area or is not specifically located at this time Note: All project locations are approximate
Approved City Park Space
(Not a Part)
Potential Future Park Area
Enhanced Recreational
Facilities (per Master Plan)
Proposed GWRS Turnout
Structure
Inflatable Rubber Dam &
River Impoundment
Trail Undercrossing
Retaining Wall
Embankment Improvements
OC River Walk Trail
Improvements

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout
PSS P
1g River Access/Kayak Ramp South of Cerritos - Existing Ramp 1h Interim UPRR Crossing at Phoenix Club Dr. - Existing RR Crossing & New Interim Connection Trail 1i Replace Access Road Only (For New Ped./Bike Bridge N. of Katella) 2a Embankment Seating and Steps
2b Metrolink RR Undercrossing - Existing Undercrossing 2c Metrolink Underpass Retaining Wall
2d River Walk South Embankment Seating and Steps
2e SR-57 Underpass Trail Widening
2f SR-57 Retaining Wall

2. Trail West Bank - Katella to Orangewood
1a UPRR - Undercrossing - New Undercrossing 3a Replace Access Road Only (For New Ped./Bike Bridge N. of Katella) 1b UPRR Undercrossing Retaining Wall 3b Improve Trail w/ Terrace & Community Access 1c UPRR - At Grade Crossing - Existing Maintenance Access 3c East Bank Park/River Terrace Retaining Wall #1 1d OC River Walk & River Road Retaining Wall 3d City of Orange Water Recreation Opportunity ¹ 1e Ball Rd. Culvert Undercrossing - Existing 14x14 RCB 3e East Bank Park/River Terrace Retaining Wall #2 1f Ball Rd. Bridge Undercrossing w/ City & County & OCWD - Existing Maintenance Access

GROUP C - NEW TRAILS & TRAIL IMPROVEMENTS

1. Trail West Bank - Katella to Anaheim Coves (6,400 LF total, 18' typ. width) 3. Trail East Bank Katella to Ball Rd.

4. Trail East Bank Katella to Orangewood: SART - Main Line Reroute to East Bank of River Proposed Improvements - Group C
OC River Walk
Feet
0 1000500N
Source: Pacific Advanced Civil Engineering Inc. (PACE), 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Figure 2-8d
Bldg #3
(F)
Bldg #5
(F)
Parking Deck B
(F)
Market &Office(F)
Concert
Hall
(F)
The
Steps(F)
Bldg #6
Bldg #2
(F)
Bldg #1
(F)
Parking
Deck D (F)
Bldg #4
(F)
Hotel (F)
Hotel (F)
Parking Deck C(F)
Hotel (E)
Parking
Deck A (F)
Honda
Center
(Existing)
ARTIC
(E)
Existing
DropStructure
Existing
DropStructure
Angel
Stadium(E)

STADIUM

PROMENADE

KINDER MORGAN

ORANGE TERMINAL

COUNTY OF
ORANGE

ISLANDS GOLF

CENTER (E)
BURRIS

BASIN (E)
(MEADOW PARK)
Metrolink RR

OC RIVER WALK PROJECT ELEMENTS
Pedestrian & Bike Bridge
Pump Station & Pipeline To/
From GWRS Turnout
PSS P
4a East Bank (City of Orange) Katella to UPRR
4b UPRR to Ball Rd.

3. OCVIBE Lot B Parking Lot, Potential Future OC River Walk Park

4. Park / River Terrace: East Bank North of Katella
1a Kayaking & Water Recreation Activities
1b Swimming / Wading Recreational Opportunity 6a Iconic Signage ¹ 1c Recirculation and Water Feature Pumps ¹ 6b Bridge Mural and Lighting 1d Water Feature Elements ¹ 6c Mosaic & Art Installations 1e Swimming Water Quality Pumps and Treatment ¹ 6d Reflective Shade Canopies 6e Zen Zone / Wildflower Space ¹
2a Kayaking & Water Recreation Activities 6f River Poetry Walk 2b Under SR-57: Lighting & Other Amenities 6g Interactive Educational Component 2c Recirculation and Water Feature Pumps ¹ 6h Wayfinding Signage ¹ 2d Water Feature Elements ¹ 6i Conceptual Locations for Art/Signage Opportunities ¹

6. Art / Education / Signage (Conceptual Locations)

2. River Recreation - South Impoundment

GROUP D - ENHANCED COMMUNITY RECREATION AMENITIES

1. River Recreation - North Impoundment 5. Riverbed Recreational Areas (Future Recreational Opportunities) Proposed Improvements - Group D
OC River Walk
Feet
0 1000500N
Source: OC River Walk Vision Plan, 2024.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
0 800400 Figure 2-10
Trail Circulation System
OC River Walk
N
OC RIVER WALK CONCEPTUAL MASTER PLAN 2024OC RIVER WALK CONCEPTUAL MASTER PLAN 2024 I. Introduction II. Design Approach III. River Reaches IV. Supplemental Information
39 40

CIRCULATION AND TRAIL TYPES
Creating an accessible, safe, and multi-modal travel corridor involves giving all people better access to convenient and continuous pedestrian paths and bike trails. Whether by bike, scooter, by foot, or public transit, the OC River Walk reimagines the area to deliver a safer and more connected corridor for people to use. Through careful analysis of the existing embankment widths and right-of-way widths, the project deploys five typical trail types across the site. The trail types are outlined below.
12-foot shared asphalt bike path separated by a planted buffer (width varies depending on available ROW width) and 12-foot split concrete and decomposed granite pedestrian path. Image:

Separated paths | Source: Pinterest
Gracious 26-foot width concrete promenade. Image: Bow River Walk | Source: Stantec
12-foot shared bike path grade separated next to a 12-foot concrete pedestrian path. Image: Rossall Seawall & Coastal Defence Scheme | Source: Visit Fylde Coast

KATELLA AVE

ARTIC RAIL ROAD

ORANGEWOOD AVE

PROPERTY LINE

PROPERTY LINE
57 COLLINS CHANNEL

RIVER ROAD

SEPARATED BIKE AND PEDESTRIAN PATHSHARED PROMENADEGRADE SEPARATED BIKE AND PEDESTRIAN PATHS

TYPICAL TRAIL CONDITIONS
UNDERCROSSING (NEW) UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)

CONNECTION TO ARTIC
SHARED PEDESTRIAN + BIKE BRIDGE
12’
12’ 12’
12’
26’

SHARED PROMENADE

SEPARATED BIKE AND

PEDESTRIAN PATH

GRADE SEPARATED BIKE

AND PEDESTRIAN PATH
10-foot cycle track with a planted buffer between a five-foot concrete pedestrian path. Image: Hudson River Bike Path | Source: Flickr
17-foot wide, with a shared asphalt bike path and a five-foot decomposed granite pedestrian path adjacent. Image: Anaheim Coves Trail | Source: Organic-Lock

STANLEY CUP
WAY

UNION PACIFIC RAILROAD

BALL ROAD
SHARED

CIRCULATION LEGEND

PEDESTRIAN ONLY

BIKE ONLY
50 100 200
FUTURE

DEVELOPMENT

SHARED MIXED USE TRAIL W/ ADJACENT SOFT PATHRAISED CYCLE TRACK WITH BUFFER

UNDERCROSSING (NEW)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
SHARED PEDESTRIAN + BIKE BRIDGE

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

RAISED CYCLE

TRACK WITH BUFFER
12’5’
12’5’
10’ 5’

ARTIC STATION
(EXISTING)

HONDA CENTER
(EXISTING)
FUTURE

ADJACENT

OPEN SPACE

FUTURE ADJACENT OPEN SPACE

BUILDING
(EXISTING)
OC RIVER WALK CONCEPTUAL MASTER PLAN 2024OC RIVER WALK CONCEPTUAL MASTER PLAN 2024 I. Introduction II. Design Approach III. River Reaches IV. Supplemental Information
39 40

KATELLA AVE

ARTIC RAIL ROAD

ORANGEWOOD AVE

PROPERTY LINE

PROPERTY LINE
57 COLLINS CHANNEL

RIVER ROAD

SEPARATED BIKE AND PEDESTRIAN PATHSHARED PROMENADEGRADE SEPARATED BIKE AND PEDESTRIAN PATHS

TYPICAL TRAIL CONDITIONS
UNDERCROSSING (NEW) UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)

CONNECTION TO ARTIC
SHARED PEDESTRIAN + BIKE BRIDGE
12’
12’ 12’
12’
26’

SHARED PROMENADE

SEPARATED BIKE AND

PEDESTRIAN PATH

GRADE SEPARATED BIKE

STANLEY CUP
WAY

UNION PACIFIC RAILROAD

BALL ROAD
SHARED

CIRCULATION LEGEND

PEDESTRIAN ONLY

BIKE ONLY
50 100 200
FUTURE

DEVELOPMENT

SHARED MIXED USE TRAIL W/ ADJACENT SOFT PATHRAISED CYCLE TRACK WITH BUFFER

UNDERCROSSING (NEW)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
SHARED PEDESTRIAN + BIKE BRIDGE

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

RAISED CYCLE

TRACK WITH BUFFER
12’5’
12’5’
10’ 5’

ARTIC STATION
(EXISTING)

HONDA CENTER
(EXISTING)
FUTURE

ADJACENT

OPEN SPACE

FUTURE ADJACENT OPEN SPACE

BUILDING
(EXISTING)

MATCHLINE

MATCHLINE
OC RIVER WALK CONCEPTUAL MASTER PLAN 2024OC RIVER WALK CONCEPTUAL MASTER PLAN 2024 I. Introduction II. Design Approach III. River Reaches IV. Supplemental Information
39 40

KATELLA AVE

ARTIC RAIL ROAD

ORANGEWOOD AVE

PROPERTY LINE

PROPERTY LINE
57 COLLINS CHANNEL

RIVER ROAD

SEPARATED BIKE AND PEDESTRIAN PATHSHARED PROMENADEGRADE SEPARATED BIKE AND PEDESTRIAN PATHS

TYPICAL TRAIL CONDITIONS
UNDERCROSSING (NEW) UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)

CONNECTION TO ARTIC
SHARED PEDESTRIAN + BIKE BRIDGE
12’
12’ 12’
12’
26’

SHARED PROMENADE

SEPARATED BIKE AND

PEDESTRIAN PATH

GRADE SEPARATED BIKE

STANLEY CUP
WAY

UNION PACIFIC RAILROAD

BALL ROAD
SHARED

CIRCULATION LEGEND

PEDESTRIAN ONLY

BIKE ONLY
50 100 200
FUTURE

DEVELOPMENT

SHARED MIXED USE TRAIL W/ ADJACENT SOFT PATHRAISED CYCLE TRACK WITH BUFFER

UNDERCROSSING (NEW)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
UNDERCROSSING (EX.)
SHARED PEDESTRIAN + BIKE BRIDGE

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

SHARED MIXED-USE

TRAIL W/ ADJACENT

SOFT PATH

RAISED CYCLE

TRACK WITH BUFFER
12’5’
12’5’
10’ 5’

ARTIC STATION
(EXISTING)

HONDA CENTER
(EXISTING)
FUTURE

ADJACENT

OPEN SPACE

FUTURE ADJACENT OPEN SPACE

BUILDING
(EXISTING)
Source: OC River Walk Conceptual Master Plan, 2025.

C:\GIS\Projects\City of Anaheim\OC River Walk\Map Docs\1st Screencheck DEIR Feet
0 800400 Figure 2-11
Project Rendering - South of Cerritos River Access
OC River Walk
N

Anaheim City CouncilDecember 9, 2025

Anaheim City Council
December 9, 2025