W912P722B0002 Dry Creek_Environmental References.pdf

August 13, 2020

In the Matter of Water Quality Certification for the Army Corps of Engineers Dry Creek Ecosystem Restoration

Reaches 1, 2, 4, 10, and 13 Project

APPLICANT: U.S. Army Corps of Engineers San Francisco District RECEIVING WATER: Dry Creek HYDROLOGIC UNIT: Middle Russian River hydrologic area (114.24) COUNTY: Sonoma FILE NAME: Dry Creek Ecosystem Restoration Reaches 1, 2, 4, 10, and 13

ECM PIN CW-866905; WDID 1B20082WNSO

FINDINGS BY THE EXECUTIVE OFFICER:

1. On May 1, 2020, Tessa Beach of the U.S. Army Corps of Engineers San Francisco District (applicant) filed an application for water quality certification (certification) under section 401 of the Clean Water Act (33 U.S.C. § 1341) with the North Coast Regional Water Quality Control Board (Regional Water Board) for activities associated with the Dry Creek Ecosystem Restoration Reaches 1, 2, 4, 10, and 13 Project (project). The application was deemed complete on August 6, 2020. The project is located on lower Dry Creek near Healdsburg at approximately latitude 38.6°N and longitude 122.88°W.

2. Public Notice: The Regional Water Board provided public notice of the application pursuant to Title 23, California Code of Regulations, Section 3858 on July 16, 2020, and posted information describing the project on the Regional Water Board’s website. No comments were received.

3. Receiving Waters: The proposed project would cause disturbances to Dry Creek, tributary to the middle Russian River hydrologic area (114.24).

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4. Project Description: The purpose of the project is to comply with requirements of the Russian River Biological Opinion issued by the National Marine Fisheries Service, by constructing instream habitat structures to enhance available habitat for steelhead and coho salmon in Dry Creek.

Background The Biological Opinion found that summer flows in the upper Russian River and Dry Creek are too high for optimal juvenile coho salmon and steelhead habitat. Six miles of habitat enhancement of Dry Creek are required to improve summer rearing conditions while allowing the Army Corps of Engineers and Sonoma Water to maintain the existing flow range from Warm Springs Dam for water supply purposes.

The habitat enhancements are to be implemented in phases to allow for evaluation of their effectiveness.

Since 2012, Sonoma Water and the Army Corps of Engineers have completed projects in Reaches 2, 4, 7, 8, 14, and 15. Work in Reach 14 was the most recently completed in 2019. The reach numbering system starts at Reach 1 at the confluence with the Russian River and ends at Reach 15 at the base of Warm Springs Dam.

The reach number does not identify river mile lengths but does approximate the river miles between the confluence with the Russian River and the base of Warm Springs Dam.

Engineering designs for the six miles of enhancement have been created. Lessons learned from earlier implementation phases are used to adapt the designs prior to implementing enhancements in later phases. Flow conditions vary in the upper, middle, and lower sections of Dry Creek. The upper section has more predictable flows from the direct influence of dam releases. The middle and lower sections are influenced by unmanaged seasonal flows from tributaries. The lower section is influenced by flow conditions in the Russian River. Engineering designs for different reaches reflect the varying flow conditions in the reaches.

Proposed Project The proposed project will involve dewatering and bypass flow pumping, stockpiling of materials, removal of vegetation, excavation of backwater alcove areas, construction of side channels, enhancement of pools, riffle construction, and placement of boulder and log structures. A bank stabilization project will occur on a tributary close to the main channel of Dry Creek.

Work will occur in the wetted portion of Dry Creek and in the adjacent riparian area.

The project will consist largely of earth work, including the installation of boulder fields and the reshaping of the wetted channel bottom to build riffles, as well as the creation of alcoves and side channels and associated revegetation. Design elements and approaches have been selected with the intent of minimizing the need for

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dewatering or channel diversion. However, to prevent excessive turbidity to the actively flowing stream during construction, it will likely be necessary to partially divert the stream around active work zones in stages through the use using coffer dams made of gravel bags or sheet piles. Equipment will not be operated in the stream channel of the flowing stream except as necessary for construction of temporary cofferdams or construction of temporary crossings.

Bank Stabilization At site 2A, a bank repair is proposed on a tributary at the confluence with Dry Creek.

The repair involves rock slope protection and vegetated soil lifts. Existing concrete rubble historically placed in the bottom of the channel will be left in place and the rip rap slope will be constructed on top of it. A 20-inch oak at the top of bank will be retained. Willows will be planted throughout the rip rap on 10-foot centers.

5. Construction Timing: Construction in or near the streambed would occur June through October during summer low flow conditions. Work window extensions may be requested if dry fall weather is predicted. Construction is expected to occur in 2021, 2022, 2023, and 2024.

6. Project Impacts: Approximately 25.632 acres of streambed and bank and riparian habitat will be temporarily impacted from the project. Approximately 0.058 acres or 2,525 square feet of stream bank will be permanently impacted from the bank stabilization project.

7. Mitigation for Project Impacts: The project is mitigation for impacts that resulted in issuance of the Russian River Biological Opinion. The project is designed to provide functional uplift to Dry Creek through habitat enhancement. The bank stabilization is considered self-mitigating due to incorporation of bioengineering elements. No further mitigation is required.

8. Project Tracking: It has been determined through regional, state, and national studies that tracking of mitigation and restoration projects must be improved to better assess their performance. In addition, to effectively carry out the state’s Wetlands Conservation Policy of no net loss to wetlands, the state needs to closely track both aquatic habitat losses and the success of mitigation and restoration projects.

Therefore, this certification requires the Applicant to upload impact totals and mitigation measures to a web-based project tracking system called “EcoAtlas” using the “Project Tracker” form, which can be found here: http://ptrack.ecoatlas.org.

Instructions and how to request a username and password are on the Project Tracker website. More information about EcoAtlas is available at: www.ecoatlas.org.

9. Disturbed Soil Area: Project implementation will result in greater than one acre of disturbed soil area. The applicant shall obtain coverage under the National Pollutant Discharge Elimination System General Permit for Storm Water Discharges Associated with Construction and Land Disturbance Activities (General Permit, Dry Creek Ecosystem Restoration - 4 - August 13, 2020

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Order 2009-0009-DWQ and subsequent revisions) and prepare a Stormwater Pollution Prevention Plan detailing best management practices (BMPs) to control pollution from the project area during construction. Section N and Finding 23 of the General Permit allow flexibility by the Regional Water Board to consider site and environmental circumstances. As much of this project takes place within waters of the state, it may be appropriate to modify certain requirements of the General Permit where work occurs within waters of the state to comply with the certification. The applicant may contact Josh Luders at Joshua.Luders@Waterboards.ca.gov or Heaven Moore at Heaven.Moore@Waterboards.ca.gov and certification staff regarding administration of the General Permit and certification at the project site.

10. Under the Porter-Cologne Water Quality Control Act, each regional water board shall establish water quality objectives to ensure the reasonable protection of beneficial uses and the prevention of nuisance, in consideration of various factors including past, present and probable future beneficial uses of water (Water Code, § 13241).

The implementation of restoration projects has the potential to cause discharges of waste into waters of the State and therefore must be regulated. These discharges are intended to be temporary in nature (during the course of construction and/or as a result of the first storm events); and may exceed water quality objectives that are included in the Water Quality Control Plan for the North Coast Region (Basin Plan) with the purpose of providing a net benefit to water quality. (From the Policy in Support of Restoration in the North Coast Region Resolution R1-2015-0001 as adopted by the Regional Water Board on January 29, 2015).

11. Other Agency Actions: The U.S. Army Corps of Engineers does not issue itself a permit, but the project has been designed to be consistent with the Department of the Army Nationwide Permit 27 for Aquatic Habitat Restoration, Establishment, and Enhancement Activities. As a federal agency, the applicant does not obtain a Streambed Alteration Agreement from the California Department of Fish and Wildlife.

12. CEQA Compliance: On November 17, 2015, Sonoma County, as lead California Environmental Quality Act (CEQA) agency, certified an Environmental Impact Report and filed with the State Clearinghouse (SCH 2014052020), pursuant to CEQA guidelines.

13. Antidegradation Policy: The federal antidegradation policy requires that state water quality standards include an antidegradation policy consistent with the federal policy. The State Water Board established California’s antidegradation policy in State Water Board Resolution 68-16, which incorporates the federal antidegradation policy where the federal policy applies under federal law. Resolution 68-16 requires that existing high-quality waters be maintained unless degradation is justified under specific provisions. The Regional Water Board’s Basin Plan implements, and incorporates by reference, both the state and federal antidegradation policies. This Certification is consistent with applicable federal and state antidegradation policies, Dry Creek Ecosystem Restoration - 5 - August 13, 2020

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as it does not authorize the discharge of increased concentrations of pollutants or increased volumes of treated wastewater, and does not otherwise authorize degradation of the waters affected by this project.

14. This discharge is also regulated under State Water Resources Control Board Order 2003-0017-DWQ, General Waste Discharge Requirements for Dredge and Fill Discharges that have Received State Water Quality Certification, which requires compliance with all conditions of this water quality certification.

https://www.waterboards.ca.gov/water_issues/programs/cwa401/docs/generalorders /go_wdr401regulated_projects.pdf

Receiving Water: Dry Creek, tributary to the middle Russian River hydrologic area (114.24)

Permanent Impacts: 0.058 acres

Temporary Impacts: 25.632 acres

Latitude/Longitude: 38.6°N/122.88°W

Certification Expiration: August 13, 2025

Accordingly, based on its independent review of the record, the Regional Water Board certifies that the Dry Creek Ecosystem Restoration Reaches 1, 2, 4, 10, and 13 Project (WDID 1B20082WNSO), as described in the application, will comply with sections 301, 302, 303, 306, and 307 of the Clean Water Act, and with applicable provisions of state law, provided that the applicant complies with the following terms and conditions:

All conditions of this Certification apply to the applicant (and all their employees) and all contractors (and their employees), sub-contractors (and their employees), and any other entity or agency that performs activities or work on the project as related to this water quality certification.

Project-Specific Conditions

1. All work shall be completed by October 15, annually. Revegetation work is not limited to this work window but must be completed within the same season as project activities. If more time is needed to complete project activities, modification of the work period may be requested in writing on a week-by-week basis. Requests for a work period extension shall: 1) describe the extent of work already completed; 2) detail the activities that remain to be completed; 3) detail the time required to complete each of the remaining activities; 4) provide photographs of both the current work completed and the proposed site for continued work; and 5) include an assessment of additional biological impacts as a result of the work extension.

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Requests for extension of the work period may be submitted to kaete.king@waterboards.ca.gov and gil.falcone@waterboards.ca.gov.

2. Willows in the bank stabilization structure shall achieve 85% success. Vegetative success of the bank stabilization structure shall be subject to the review and acceptance by Regional Water Board staff, and shall not be considered successful until a minimum of five years of monitoring has occurred. Plants shall not be considered successful until irrigation has been terminated for a minimum of two years.

3. Vegetative success of project plantings shall be subject to the review and acceptance by Regional Water Board staff, and shall not be considered successful until a minimum of five years of monitoring has occurred. Plants shall not be considered successful until irrigation has been terminated for a minimum of two years.

4. Within 30 days of issuance of this Order, the Applicant shall upload Project information to EcoAtlas using the “Project Tracker” form found at the following website: http://ptrack.ecoatlas.org/. Required information includes a Project map that may either be uploaded to EcoAtlas or created within EcoAtlas by using the “draw polygon” tool.

5. The mitigation measures detailed in the Environmental Impact Report (SCH 2014052020) are hereby incorporated by reference and are conditions of approval of this certification. Notwithstanding any more specific conditions in this certification, the applicant shall comply with all mitigation measures identified in the Environmental Impact Report that are within the Regional Water Board’s jurisdiction.

Project Specific Conditions Requiring Reports

6. No later than 14 days prior to commencement of construction, the applicant shall submit a copy of the final dewatering plan.

7. This Order provides an allowable zone of turbidity dilution within which turbidity levels may be increased to more than 20 percent above naturally occurring background levels. During in-stream project construction activities that may cause elevated turbidity above background levels, the Applicant shall monitor turbidity levels upstream within 50 feet of project activities (i.e. natural background) and 500 feet downstream of the in-stream construction activities (point of compliance) that could increase turbidity. At a minimum, field turbidity measurements shall be collected whenever a visible increase in turbidity is observed. Monitoring frequency shall be a minimum of every two hours during in-stream work periods and when activities commence that are likely to increase turbidity levels above any previously monitored levels. If sample results at the point of compliance indicate that turbidity levels exceed 20 percent above naturally occurring background or 20 NTUs, Dry Creek Ecosystem Restoration - 7 - August 13, 2020

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whichever is greater, remedial actions will be implemented to reduce and maintain turbidity at or below this threshold level at the point of compliance. Potential remedial actions include halting or slowing construction activities and implementation of additional Best Management Practices (BMPs) until turbidity levels are at or below 20 percent above naturally occurring background or 20 NTUs, whichever is greater.

If naturally occurring background levels are greater than 20 NTUs, turbidity levels at the point of compliance shall not exceed 20 percent above the naturally occurring background level. A monitoring report containing all turbidity measurements shall be submitted in a tabular format to the Regional Water Board upon annual project completion. The monitoring report shall be written in a manner that clearly demonstrates compliance with all water quality monitoring requirements.

8. The applicant shall submit as-built summary reports each year of active construction on the project summarizing the work that was completed, what work remains, if changes were made to the design, and if problems were encountered during construction. As-built summary reports shall be submitted by December 31 after each season of active construction.

9. The applicant shall submit annual reports on the implementation, effectiveness, and validation monitoring conducted per the with the Dry Creek Adaptive Management Plan. This monitoring is designed to quantitatively evaluate and determine the effectiveness of habitat enhancement elements in creating beneficial effects for salmonids. Reports shall be submitted annually by April 1 to Northcoast@waterboards.ca.gov.

10. The applicant shall report on the stability and vegetative success of the bank stabilization annually for a minimum of 5 years. The report shall include photos that show the extent of vegetative cover over the structure. This reporting may be included with the overall reporting for the project per the Dry Creek Adaptive Management Plan.

11. Regional Water Board staff shall be notified in writing at least five working days prior to the commencement of ground disturbing activities, with details regarding the construction schedule, in order to allow staff to be present onsite during construction, and to answer any public inquiries that may arise regarding the project.

Standard Conditions

12. This certification action is subject to modification or revocation upon administrative or judicial review, including review and amendment pursuant to Water Code section 13330 and title 23, California Code of Regulations, section 3867.

13. This certification action is not intended and shall not be construed to apply to any discharge from any activity involving a hydroelectric facility requiring a Federal Energy Regulatory Commission (FERC) license or an amendment to a FERC

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license unless the pertinent certification application was filed pursuant to title 23, California Code of Regulations, section 3855, subdivision (b) and the application specifically identified that a FERC license or amendment to a FERC license for a hydroelectric facility was being sought.

14. The validity of this certification is conditioned upon total payment of any fee required under title 23, California Code of Regulations, section 3833, and owed by the applicant.

15. This certification does not authorize drafting of surface waters. Any drafting of surface waters shall be in compliance with state water rights law and diversion requirements overseen by the State Water Resources Control Board’s Division of Water Rights.

16. Only wildlife-friendly, 100 percent biodegradable erosion and sediment control products that will not entrap or harm wildlife shall be used. Erosion and sediment control products shall not contain synthetic (e.g., plastic or nylon) netting. Photodegradable synthetic products are not considered biodegradable. The applicant shall request approval from the Regional Water Board if an exception from this requirement is needed for a specific location.

17. Only 100 percent biodegradable geotextiles shall be used for permanent applications within waters of the state unless explicitly approved for specific purposes in the project design.

18. Best management practices (BMPs) shall be implemented according to the submitted application and the conditions in this certification. BMPs for erosion, sediment, and turbidity control shall be implemented and in place at commencement of, during, and after any ground clearing activities or any other project activities that could result in erosion or sediment discharges to surface water. BMPs shall be immediately available for deployment at all times to prevent discharges to waters of the state.

19. The applicant is prohibited from discharging waste to waters of the state, unless explicitly authorized by this certification. For example, no debris, soil, silt, sand, bar, slash, sawdust, cement or concrete washings, oil or petroleum products, or other organic or earthen material from any construction or associated activity of whatever nature, other than that authorized by this Certification, shall be allowed to enter into or be placed where it may be washed by rainfall into waters of the state. When operations are completed, any excess material or debris shall be removed from the work area.

20. The Applicant is liable and responsible for the proper disposal, reuse, and/or recycling of all Project-generated waste in compliance with applicable state and federal laws and regulations.

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21. The applicant shall provide Regional Water Board staff access to the project site to document compliance with this certification.

22. Work in flowing or standing surface waters, unless otherwise proposed in the project description and approved by the Regional Water Board, is prohibited.

23. If, at any time, an unauthorized discharge to surface water (including wetlands, lakes, rivers, or streams) occurs, or any water quality problem arises, the associated project activities shall cease immediately until adequate BMPs are implemented including stopping work. The Regional Water Board shall be notified promptly and in no case more than 24 hours after the unauthorized discharge or water quality problem arises.

24. All project activities shall be implemented as described in the submitted certification application package and the findings and conditions of this certification. Subsequent project changes that could significantly impact water quality shall first be submitted to Regional Water Board staff for prior review, consideration, and written concurrence. If the Regional Water Board is not notified of a significant alteration to the project, it will be considered a violation of this certification, and the applicant may be subject to Regional Water Board enforcement actions.

25. Prior to implementing any change to the project that may be a material change as defined in California Water Code section 13260(c) as a proposed change in character, location, or volume of the discharge, the applicant shall obtain prior written approval of the Regional Water Board Executive Officer. If the Regional Water Board is not notified of the material change to the discharge, it will be considered a violation of this certification, and the applicant may be subject to Regional Water Board enforcement action(s).

26. The applicant shall provide a copy of this Certification and State Water Board Order 2003-0017-DWQ to any contractor(s), subcontractor(s), and utility company(ies) conducting work on the project, and shall require that copies remain in their possession at the work site. The applicant shall be responsible for ensuring that all work conducted by its contractor(s), subcontractor(s), and utility companies is performed in accordance with the information provided by the applicant to the Regional Water Board.

27. Disturbance or removal of existing vegetation as detailed within the application shall not exceed the minimum necessary to complete the project.

28. Fueling, lubrication, maintenance, storage, and staging of vehicles and equipment shall not result in a discharge or threatened discharge to any waters of the state including dry portions of the creek. At no time shall the applicant or its contractors allow use of any vehicle or equipment that leaks any substance that may impact water quality.

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29. The Applicant shall not use leaking vehicles or equipment within state waters or riparian areas. Vehicles and equipment used within state waters shall be checked for leaks at the beginning of each workday.

30. In the event of any violation or threatened violation of the conditions of this Certification, the violation or threatened violation shall be subject to any remedies, penalties, process or sanctions as provided for under applicable state or federal law.

For the purposes of section 401 (d) of the Clean Water Act, the applicability of any state law authorizing remedies, penalties, process or sanctions for the violation or threatened violation constitutes a limitation necessary to assure compliance with the water quality standards and other pertinent requirements incorporated into this Certification. In response to a suspected violation of any condition of this certification, the Regional Water Board may require the holder of any federal permit or license subject to this Certification to furnish, under penalty of perjury, any technical or monitoring reports the Regional Water Board deems appropriate, provided that the burden, including costs, of the reports shall bear a reasonable relationship to the need for the reports and the benefits to be obtained from the reports. In response to any violation of the conditions of this Certification, the Regional Water Board may add to or modify the conditions of this Certification as appropriate to ensure compliance pursuant to Section 13267 of the Porter-Cologne Water Quality Control Act.

31. The Regional Water Board may add to or modify the conditions of this Certification, as appropriate, to implement any new or revised water quality standards and implementation plans adopted and approved pursuant to the Porter-Cologne Water Quality Control Act or section 303 of the Clean Water Act.

32. In the event of any change in control of ownership of land presently owned or controlled by the applicant, the applicant shall notify the successor-in-interest of the existence of this certification by letter and shall email a copy of the letter to the Regional Water Board at the following email address:

NorthCoast@waterboards.ca.gov.

The successor-in-interest shall email the Regional Water Board Executive Officer at:

NorthCoast@waterboards.ca.gov to request authorization to discharge dredged or fill material under this certification. The request must contain the following:

i) Effective date of ownership change;

ii) Requesting entity’s full legal name;

iii) The state of incorporation, if a corporation;

iv) The address and phone number of contact person; and

v) A description of any changes to the Project or confirmation that the successor-in-interest intends to implement the project as described in this certification.

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33.Except as may be modified by any preceding conditions, all certification actions are contingent on:

i) the discharge being limited to and all proposed mitigation being completed in strict compliance with the applicant’s Project description, and

ii) compliance with all applicable requirements of the Water Quality Control Plan for the North Coast Region (Basin Plan).

34.The authorization of this certification for any dredge and fill activities expires on August 13, 2025. Conditions and monitoring requirements outlined in this Certification are not subject to the expiration date outlined above, and remain in full effect and are enforceable.

Conditions 6-11 are requirements for information and reports. Any requirement for a report made as a condition to this certification is a formal requirement pursuant to California Water Code section 13267, and failure or refusal to provide, or falsification of such required report is subject to civil liability as described in California Water Code, section 13268.

If you have any questions or comments, please contact Kaete King of my staff, at (707) 576-2848, or via e-mail at Kaete.King@waterboards.ca.gov.

Matthias St. John Executive Officer

200813_KRK_dp_Dry Creek Ecosystem 401

Original to: United States Army Corps of Engineers, San Francisco District, Attn: Tessa Beach, 450 Golden Gate Ave., San Francisco, CA 94102 Tessa.E.Bernhardt@usace.army.mil cc: State Water Resources Control Board, Stateboard401@waterboards.ca.gov Jennifer Siu, EPA Wetlands Office, siu.jennifer@epa.gov Ellie Covington, ACOE, Ellie.L.Covington@usace.army.mil Jeneya Fertel, ACOE, Jeneya.A.Fertel@usace.army.mil Dave Cuneo, Sonoma Water, David.Cuneo@scwa.ca.gov

Digitally signed by Jonathan Warmerdam Date: 2020.08.13 15:41:11 -07'00'

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i

DRY CREEK ECOSYSTEM RESTORATION

FINAL FEASIBILITY REPORT

AND ENVIRONMENTAL ASSESSMENT

General Investigation Sonoma County, California

Last Updated: 2020

ES-I

DRY CREEK ECOSYSTEM RESTORATION FINAL FEASIBILITY STUDY

AND ENVIRONMENTAL ASSESSMENT

SONOMA COUNTY, CA

E XEC UTIV E SUMMA RY

Study Authority/Purpose. The governing authority for this study and project implementation

(construction) is Section 1028 (Clarification of Mitigation Authority) of the Water Resources

Reform and Development Act of 2014.

Project Location. The project is located in the lower Dry Creek watershed in the interior coast range of northern Sonoma County, approximately 30 miles from the Pacific Ocean and 60 miles north of San Francisco Bay. Dry Creek is 32 miles long and drains 217 square miles of rugged terrain in the southwestern portion of the Russian River Basin. The Dry Creek Ecosystem

Restoration Project is located along the approximately 14 miles of Dry Creek that meanders downstream of Warm Springs Dam (WSD) to its confluence with the Russian River near the City of

Healdsburg, California. The Russian River is 110 miles long and drains 1,485 square miles of

Sonoma and Mendocino counties before it’s confluence with the Pacific Ocean near Jenner, California.

Background. The U.S. Army Corps of Engineers (USACE) constructed the WSD in 1983 to provide flood control, water storage, and outdoor recreation. The construction of WSD established

Lake Sonoma, which when full has a surface area of more than 2,700 acres and 50 miles of shoreline. During summer months, the WSD water supply releases into Dry Creek resulting in higher water levels at higher velocities than would naturally occur in summer. During the winter, WSD flood risk management operations reduce flows. The altered hydrology resulting from WSD regulation of stream flow on Dry Creek has created ideal conditions for riparian vegetation overgrowth while failing to provide large enough flood events to erode vegetated bars and expose bare surfaces for primary vegetation succession. The combination of altered hydrology caused by the dam’s regulation of the stream and vegetation growth patterns has curtailed the fluvial processes which would otherwise create complex channel and floodplain habitats. Without these fluvial processes, there has been severely limited creation of stream habitats below WSD such as alcoves, backwaters, and side channels that are important for native fish and wildlife species including all life stages of salmonid species currently listed threatened or endangered under the Endangered Species

Act (ESA) (Inter-Fluve 2011).

The construction and operation of the dam also directly resulted in the loss of upstream spawning and rearing habitat for Russian River salmonids. Between 1995 and 1999, three species of salmonids native to the Russian River watershed were listed under the ESA as threatened or endangered, including the endangered central California coast (CCC) coho salmon (Oncorhynchus kisutch) and the threatened California coastal (CC) Chinook salmon (O. tshawytscha) and CCC steelhead (O. mykiss)

ES-II

trout. Since this time, the USACE has been involved in many programs and partnerships aimed at restoring salmonid populations.

On September 24, 2008, the National Oceanic and Atmospheric Administration National Marine

Fisheries Service (NMFS) issued the “Jeopardy Biological Opinion (BO) for Water Supply, Flood

Control, and Channel Maintenance Activities for the Russian River Watershed” (NMFS 2008) for the operation of WSD. A Reasonable and Prudent Alternative of this BO stipulates that the

USACE and Sonoma County Water Agency (Sonoma Water) should perform various actions to save threatened salmonid species in the Russian River Watershed. These include the enhancement of 6 miles of Dry Creek between WSD and its confluence with the Russian River to provide near ideal summer rearing conditions for coho and steelhead. In order to meet the BO requirements, Sonoma

Water delineated Dry Creek into 26 potential restoration subreaches based on restoration opportunities.

While the 2008 BO is taken into consideration, the federal objective for ecosystem restoration projects is to maximize net National Ecosystem Restoration (NER) benefits. Further, this General

Investigation Ecosystem Restoration Project must not conflict with the authorized purposes of the existing WSD project (flood control, water storage, and outdoor recreation). The plan formulation process for this study identified the water and related land resources problems and opportunities in the study area and built on that foundation to develop planning objectives, constraints, measures and alternatives.

Project Goals and Objectives. The overall project goal is to reconnect the channel to the floodplain and to restore the quality and diversity of aquatic and riparian habitat along lower Dry

Creek, below WSD, by restoring instream and floodplain habitat complexity, riparian vegetation diversity, and productive backwater habitat. The restoration of aquatic and riparian habitat is expected to facilitate the recovery of federally ESA listed coho salmon and steelhead trout. Specific project objectives are listed below:

Restore stream and floodplain complexity and increase cover to benefit aquatic species

Improve lateral instream-floodplain connectivity

Reduce non-native vegetation and increase native riparian vegetation successional complexity in order to promote habitat diversity for riparian wildlife, to provide food and cover for aquatic wildlife, and to shade Dry Creek and associated floodplain features such as backwaters and side channels.

Restore high quality instream, riparian, and floodplain habitat conditions along areas of Dry

Creek’s mainstem to benefit native and special status fish and wildlife species throughout their life cycle.

Alternatives Considered. In addition to the no-action alternative, seven action alternatives were considered in detail during the final array analysis for aquatic ecosystem restoration within various subreaches along 14 miles of lower Dry Creek below WSD. Unlike many USACE projects, where

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the alternatives are combinations of various measures, this project’s alternative formulation is primarily based on combinations of various river subreaches. All alternatives include numerous stream and floodplain restoration measures (e.g. combinations of riffle construction, installation of large woody debris or boulders, construction of backwaters and side channels, vegetation management, etc.) at one or more subreach sites along Dry Creek. A graphical depiction of some of the restoration measures being implemented on Dry Creek and considered for this study is shown in

Figure ES-1.

Figure ES-1. Examples of Restoration Measures

Cost Effectiveness and Incremental Cost Analysis. Ecosystem restoration benefits of the seven action alternatives were evaluated using the US Fish and Wildlife Service’s (USFWS) Habitat

Evaluation Procedures (HEP) with a Habitat Suitability Index (HSI) for coho salmon. A HEP analysis to evaluate effects to terrestrial riparian habitats was also performed by USFWS using the yellow warbler and hairy woodpecker HSIs. Each alternative’s net annual benefits were combined with annualized cost estimates to determine their cost effectiveness using the Institute of Water

Resources planning suite software. Analysis of cost effectiveness, in general, compares the relative costs and benefits of alternative plans. The most efficient plans that provide the greatest increase in

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output for the least increase in cost are called the Best Buys. The table below summarizes the incremental cost analysis results.

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Table ES-1. Summary of Cost Effectiveness and Incremental Cost Analysis - Best Buy/Focused Array of Alternatives

Best Buy ID Reaches

AAHU1

Outputs

Average Annual Cost

Average Annual Cost Per AAHU

Incremental Average Annual Cost

Incremental Output (AAHU)

Incremental Average Annual Cost Per Output

No Action 0 $0

1 4c 3.71 $151,150 $40,741 $151,150 3.71 $40,741

2 4c, 2a 11.64 $500,670 $43,012 $349,520 7.93 $44,075

3 4c, 2a 13a 12.32 $524,240 $44,013 $41,570 0.68 $61,132

(NER) 4c, 2a 13a, 1,10, 13b 22.82 $1,247,480 $54,666 $705,240 10.50 $67,165

5 4c, 2a 13a, 1,10, 13b, 4b 25.16 $1,411,010 $56,081 $163,530 2.34 $69,884

6 4c, 2a 13a, 1,10, 13b, 4b, 7b 26.96 $1,539,190 $57,091 $128,180 1.80 $71,211

7 4c, 2a 13a, 1,10, 13b, 4b, 7b, 5b 28.05 $1,725,700 $61,522 $186,510 1.09 $171,110

1 Average Annualized Habitat Units i

Recommended Plan. Alternative 4 is the Recommended Plan (Figure ES-2). It is the NER plan that reasonably maximizes ecosystem restoration benefits compared to costs. Alternative 4 is efficient, acceptable, complete and effective in meeting project objectives by increasing habitat complexity and connectivity, decreasing invasive plant species, restoring riparian vegetation diversity, and restoring high quality instream and floodplain habitat conditions to benefit listed salmonid species throughout their life cycle. Alternative 4 will also improve lateral connectivity and access for

ESA listed coho salmon and steelhead trout to spawning habitats in the upper watersheds of Mill

Creek, Pena Creek, Grape Creek, and Fall Creek. The recommended plan does not negatively impact the ability of the WSD to meet its authorized project purposes of flood control, water storage, and outdoor recreation since no changes to dam operations are proposed.

Figure ES-2. Recommended Plan. Selected NER subreaches are shown in green and yeild approximately 2.6 river miles of restoration.

Project Costs and Benefits.

Based on October 2018 price levels, the estimated total project first cost of the recommended plan is $44,768,306. The Federal share of the total project cost after adjustment for non-Federal Lands, Easements, Rights-of-Way, Relocation and Disposal Areas (LERRDs) contributions, would be about

$29,099,391 and the non-Federal share would be about $15,668,915, which equates to 65 percent

Federal and 35 percent non-Federal. Of the total cost, LERRDs costs are approximately $5,690,146.

There is an administrative cost of $1,787,518 for the non-Federal sponsor (Sonoma Water) and an administrative cost of $1,117,199 for the Federal government included in the LERRDs. The total area of available habitat created over the life of the project is approximately 47 acres. The total annual NER benefits (average annual habitat units) are 22.82 at a cost of $953,000 per acre.

ii

The total project cost includes $2,727,429 for environmental monitoring, and adaptive management.

Sonoma Water and USACE would be responsible for the monitoring and adaptive management jointly until ecological success is met for up to 10 years. Operation, maintenance, repair, replacement, and rehabilitation (OMRR&R) of the project after implementation is the responsibility of Sonoma Water, a cost currently estimated at about $195,144 per year. Based on a 2.875-percent

(Oct 2018) discount rate and a 50-year period of analysis, the total equivalent average annual costs of the project are estimated to be $1,983,296 including operation and maintenance.

Findings and Conclusions. The NER plan was selected as the Recommended Plan. The

Recommended Plan consists of restoration of 2.6 miles of river (47 acres) with a project first cost of approximately 44 million dollars resulting in 23 average annual habitat units. Restoration of Dry

Creek aquatic and riparian habitat is significant on a state, regional, and national scale. Since the 20th century, the United States has experienced a dramatic decline of freshwater aquatic and riparian ecosystems and dams have been a major driver of this decline with over 600,000 miles of rivers blocked by dams (Carney 2000). WSD is no exception. When constructed in 1984, WSD blocked access to upstream historical fish spawning and rearing habitats, dramatically altered downstream flows, decreased riparian and aquatic habitat quality, and disrupted sediment transport to Dry Creek and the Russian River. To partially offset these impacts, USACE has been operating the Warm

Springs fish hatchery at WSD to bolster the populations of ESA-listed coho salmon and steelhead trout. However, fisheries populations continued to decline in Dry Creek and the Russian River. In

California, the state stands to lose 45% of its remaining native salmonids, including 11 of 21 anadromous species in the next 50 years unless significant actions are taken to stem the decline

(Moyle et al. 2017). In addition to impacts on fisheries, WSD has also reduced the quality of riparian habitat within Dry Creek. In the western United States, riparian areas comprise less than 1 percent of the land area, but they are among the most productive and valuable natural resource (Naiman et

al. 1993).

Dry Creek affords an important opportunity for the restoration of stream habitat because unlike unmanaged systems, the WSD water management regime (i.e. consistent summer low flows and attenuated winter flood flows) provides readily available cold water for downstream habitat. This cold water from WSD is incredibly scarce in this part of California and is becoming increasingly scarce across the American West. This scarcity of cold water, exacerbated by global climate change

(described in Section 4.1 and Appendix O), has contributed to the decline of freshwater aquatic ecosystems. The operation of WSD ensures that Dry Creek will remain a stable cold water refuge while other streams in the area are increasingly affected by rising temperatures. As described in

Section 2.4, the one piece that Dry Creek is missing is the habitat complexity and connectivity that allows aquatic ecosystems to thrive. This provides an opportunity to create habitat that will prevent the extinction and/or extirpation of ESA-listed salmonids and other aquatic species. This opportunity comes at a critical moment in these species’ recovery trajectory and USACE, as the owner and operator of the dam and hatchery, is uniquely positioned to execute this piece of the species recovery.

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Table of Contents

(*integrated NEPA section)

EXECUTIVE SUMMARY .............................................................................................................................. I

List of Tables vii

List of Figures viii

ACRONYMS ..................................................................................................................................................... iii

INTRODUCTION

Study purpose and need

Study Authority*

Lead Federal Agency and Non–Federal Sponsor*

Study Scope

Study Area*

Views of Federal and State Resource Agencies and Tribes

Format of Report

Regulatory Compliance*

Problems, Opportunities, Objectives and Constraints

Project Background: A Changing Landscape

2008 Biological Opinion

Ongoing Restoration Efforts

Problems and Opportunities

Resource Significance – Technical, Institutional, Public iv

Planning Objectives

Planning Constraints

Planning Considerations

Existing Environmental Setting*

Physiography

Geology

Seismicity and Seismic Hazards

Soils

Hydrology

Geomorphology

Water Quality

Air Quality

Noise

Ecological Setting and Resources

Cultural Resources

Socio-economics and Environmental Justice v

Land Use

Recreation

Aesthetics

Hazardous, Toxic, and Radioactive Wastes

Future Without Project Conditions*

Hydrology, Hydraulics and Geomorphology

Aquatic Habitat, Salmonids, Riparian Habitat

Plan Formulation

The Planning Process

Alternatives Formulation

Alternative Evaluation

Alternative Comparison

Final Array of Alternatives

NER and Recommended Plan Identification

Recommended Plan*

Restoration Summary vi

Operations and Maintenance

Monitoring and Adaptive Management

Real Estate Considerations

Schedule for PED and construction

Project Costs and Cost Sharing Apportionment

Consistency with USACE Campaign Plan

Consistency with USACE Environmental Operating Principles

Plan Implementation

NEPA Environmental Effects Analysis*

Alternatives Evaluated

Scope of the Environmental Effects Analysis

Affected Environment and Consequences vii

Compliance with Environmental Laws and Regulations

Recommendations

References

LI ST O F TABLE S

Table ES-1. Summary of Cost Effectiveness and Incremental Cost Analysis - Best Buy/Focused

Array of Alternatives .................................................................................................... IV

Table 2. Overview of IFR/EA

Table 3. Technical, Institutional, and Public Significance

Table 4. Potential Rock Types That May Underlie Dry Creek

Table 5. Fish Species Observed at Downstream Migrant Trap Operated by Sonoma Water in the

Spring and Summer Months in Dry Creek from 2009 to 2014

Table 6. Threatened or Endangered Fish Species, and Associated Critical Habitat, Potentially

Occurring Within the Study Area

Table 7. Sonoma County and State of California Population and Income Statistics

Table 8. Federal and State Records Databases Used in HTRW Assessment

Table 9. Sites Identified by the Records Search to Exhibit a Recognized Environmental

Condition

Table 10. Types of Ecosystem Measures Considered

Table 11. Subreach Potential Habitat Benefit Scoring

Table 12. Summary of quantitative restoration subreach scoring and associated potential habitat restoration areas (Inter-Fluve 2012)

Table 13. Qualitative Subreach Screening for Final Alternative Analysis

Table 14. Seven Best Buy Plans (2017 Price Level)

Table 15. Coho HSI Model Variables Used for the Dry Creek GI Study

Table 16. Summary of Benefits (AAHUs) to the coho Salmon for Each Subreach Evaluated

Table 17. Summary of Variables Included in the Riparian Habitat Suitability Index Models

Table 18. Summary of Net (with- minus without- project) Habitat Outputs (AAHUs) for the

Yellow Warbler and Hairy Woodpecker by Subreach

Table 19. Final Set of Best Buy Plans (coho only)

Table 20. Summary of Planning Evaluation Criteria and Objective Ratings per Alternative

Table 21. Final Array of Alternatives Costs and Benefits

Table 22. OMRR&R Cost Breakdown

Table 23. Schedule for PED and Construction Phases

Table 24. Recommended Plan Project Cost Summary1 viii

Table 25. Cost Apportionment

Table 26. Evaluated Final Alternatives

Table 27. Peak Flow Estimates

Table 28. Waters of the U.S. Present in the Subreaches Proposed for Restoration

Table 29. Restored Waters of the U.S. by Subreach

Table 30. Average Airborne Noise Levels (dBA) Associated with Construction Equipment

Table 31. Public Access Conditions Along Subreaches Proposed for Restoration

Table 32. Summary of Potential HTRW RECs Subreach

Table 33. Summary of Environmental Compliance

L IS T O F F IGURE S

Figure ES-1. Examples of Restoration Measures ........................................................................... III

Figure ES-2. Recommended Plan ...................................................................................................... i

Figure 3. Project Area

Figure 4. Regional Map

Figure 5. Dry Creek Study Reaches

Figure 6. Lower Dry Creek Reaches and Subreaches

Figure 7. Example of vegetative establishment from 1976 to 2004

Figure 8. Dry Creek Watershed Boundary

Figure 9. Geologic Map of the Lower Dry Creek Valley and Surrounding Areas, Figure 10. Lineaments of the Healdsburg Fault along the Dry Creek Study Area

Figure 11. Mean Monthly Temperature and Precipitation at Healdsburg (Station 043875), 1893-

2009.a

Figure 12. Sub-watershed Boundaries in lower Dry Creek

Figure 13. Median Monthly Flows (cfs) for Dry Creek at Geyserville Stream Gauge (USGS

#11465200) – Pre and Post WSD

Figure 14. Peak Flow Reduction by WSD

Figure 15. Pre- and Post-Warm Springs Dam Peak discharge (cubic ft per second) for Dry Creek at Geyserville stream gauge

Figure 16. Dry Creek Channel evolution

Figure 17. Example of riparian vegetation conditions and its impact on lower Dry Creek geomorphology

Figure 18. Example of Vegetative Narrowing of Channel Corridor near Lambert Bridge (RM

6.6)

Figure 19. Air Basins and Air Districts in the Study Area

Figure 20. General scheme of plant succession in the riparian zone (Source: Tabacchi et al, 1998)

Figure 21. Natural (left side) Versus Disturbed (right side) Riparian Vegetation Communities. . 58 ix

Figure 22. Estimated velocities for lower Dry Creek pools based on 2009 habitat inventory data

Figure 23. Dry Creek General Investigation Alternative Formulation Process

Figure 24. Three geomorphic segments of Dry Creek

Figure 25. Delineated Subreaches Along Dry Creek

Figure 26. Focused Array Subreaches: 1, 2a, 4b, 4c, 5a, 5b, 7b, 10, 13a, 13b, 14a, and 14b

Figure 27. Final Array Subreaches: 1, 2a, 4b, 4c, 5b, 7b, 10, 13a, and 13b

Figure 28. Reach 1 Restoration Design

Figure 29. Subreach 2a (downstream)

Figure 30. Subreach 2a (upstream) restoration design

Figure 31. Subreach 4b Restoration Design

Figure 32. Subreach 4c Restoration Design

Figure 33. Subreach 5b (downstream) Restoration Design

Figure 34. Subreach 5b (upstream) Restoration Design

Figure 35. Subreach 7b (downstream) Restoration Design

Figure 36. Subreach 7b (upstream) Restoration Design

Figure 37. Reach 10 (upstream) Restoration Design

Figure 38. Reach 10 (middle) Restoration Design

Fig…