COASTAL CONSERVANCY Staff Recommendation May 27, 2021 TIJUANA RIVER VALLEY – SMUGGLER’S GULCH IMPROVEMENTS Project No. 21-010-01 Project Manager: Sam Jenniches RECOMMENDED ACTION: Authorization to disburse up to $10,000,000 to the County of San Diego to implement the Tijuana River Valley – Smuggler’s Gulch Improvements Project, and adoption of findings under the California Environmental Quality Act. LOCATION: Tijuana River Valley Regional Park, County of San Diego EXHIBITS Exhibit 1: Project Maps Exhibit 2: Project Photos Exhibit 3: Project Letters Exhibit 4: Addendum to the Initial Study/Mitigated Negative Declaration April 2021 for the Regional General Permit 53 Project RESOLUTION AND FINDINGS Staff recommends that the State Coastal Conservancy adopt the following resolution and findings. Resolution: The State Coastal Conservancy hereby authorizes a grant of an amount not to exceed ten million dollars ($10,000,000) to the County of San Diego (“the grantee”) to implement the Tijuana River Valley – Smuggler’s Gulch Improvements Project in Tijuana River Valley Regional Park in the County of San Diego. Prior to commencement of the project, the grantee shall submit for the review and written approval of the Executive Officer of the Conservancy (Executive Officer) the following: 1. A detailed work program, schedule, and budget. 2. Names and qualifications of any contractors to be retained in carrying out the project. 3. A plan for acknowledgement of Conservancy funding. Page 1 of 11 TIJUANA RIVER VALLEY – SMUGGLER’S GULCH IMPROVEMENTS 4. Evidence that all permits and approvals required to implement the project have been obtained. 5. A written agreement with the City of San Diego sufficient to enable the grantee to implement, operate, and maintain the portion of the project located on property owned by the City of San Diego. Findings: Based on the accompanying staff recommendation and attached exhibits, the State Coastal Conservancy hereby finds that: 1. The proposed authorization is consistent with Chapters 3 and 5.5 of Division 21 of the Public Resources Code, regarding funding a project identified by the Tijuana River Valley Needs and Opportunities Assessment and integrated coastal and marine resources protection, respectively. 2. The proposed project is consistent with the current Conservancy Project Selection Criteria and Guidelines. 3. The Conservancy has independently reviewed and considered the Regional General Permit (RGP) 53 Project Initial Study/Mitigated Negative Declaration (IS/MND) adopted on May 28, 1998, by the County Board of Supervisors and the Addendum to the Initial Study/Mitigated Negative Declaration April 2021 for the Regional General Permit 53 Project adopted by the County Board of Supervisors on April 23, 2021 pursuant to the California Environmental Quality Act (“CEQA”) and attached to the accompanying staff recommendation as Exhibit 4. The Conservancy finds that the proposed project as designed and mitigated avoids, reduces, or mitigates the potentially significant environmental effects to a less-than-significant level, and that there is no substantial evidence based on the record as a whole that the project may have a significant effect on the environment, as defined in 14 Cal. Code Regulations Section 15382. STAFF RECOMMENDATION PROJECT SUMMARY: Staff recommends the Conservancy authorize a $10,000,000 grant to the County of San Diego for implementation of the Tijuana River Valley – Smuggler’s Gulch Improvements Project (proposed project) in Tijuana River Valley Regional Park in San Diego County. The proposed project consists of installing a permanent sediment basin and trash booms in a tributary to the Tijuana River, and improving an existing culvert under Monument Road. The proposed project includes preparation of permit applications and final designs. The proposed project will reduce the movement of trash and sediment into the Tijuana River Valley (TRV) as well as reduce localized flooding at Monument Road. Page 2 of 11 TIJUANA RIVER VALLEY – SMUGGLER’S GULCH IMPROVEMENTS Despite various efforts over the last several decades, the Tijuana River and canyon tributaries such as Smuggler’s Gulch remain some of the most polluted waterways in the San Diego region. Dry-weather flows from the Tijuana River are typically treated by the International Boundary and Water Commission’s (IBWC)’s existing diversion system, but following rain events, transboundary flows containing sewage, trash, and excessive amounts of sediment often exceed the diversion system’s capacity and reach the Tijuana River untreated. This can happen at any time of the year. Polluted flows from the Tijuana River threaten the health of residents in the U.S. and Mexico, impact important estuarine habitat and waters of international significance, cause beach closures, damage agricultural resources, adversely impact the economy, compromise border security operations, and have the potential to affect U.S. military readiness as there are military training installations within the impacted area. Section 303(d) of the federal Clean Water Act requires that states identify impaired water bodies on the Clean Water Act Section 303(d) List of Water Quality Limited Segments (303(d) List). The State of California has identified the lower Tijuana River, the Tijuana River Estuary, and the downstream Pacific Ocean shoreline as impaired on the 303(d) List. Twenty pollutants, including indicator bacteria (primarily from sewage), sediment, and trash, are included on the 303(d) List for causing impairments to these water bodies and their designated beneficial uses. In 2009, the San Diego Regional Water Quality Control Board formed the Tijuana River Valley Recovery Team to identify measures to be implemented in Mexico and the U.S. to reduce flows, intercept/divert wastes, and restore damaged habitats. The resulting Tijuana River Valley Recovery Strategy: Living with the Water (Recovery Strategy) identified several potential projects that could be implemented to address water quality impairment issues. In March 2020, the County of San Diego (County) completed the Tijuana River Valley Needs and Opportunities Assessment (NOA) Report to provide decision makers with project options that could be implemented within the U.S. to protect human and environmental health by controlling transboundary flows of sewage, trash, and sediment entering the Tijuana River Valley. The Smuggler’s Gulch Improvements project is identified as a priority in the NOA Report and was endorsed and identified as one of the top three priorities by the San Diego Regional Water Quality Control Board, City of San Diego, County of San Diego, City of Imperial Beach, City of Chula Vista, City of National City, Port of San Diego, Surfrider Foundation, and California State Lands Commission in the San Diego Regional Water Quality Control Board’s joint Resolution R9- 2019-0246, adopted December 11, 2019. Smuggler’s Gulch is a small tributary creek that flows from Tijuana, across the border, through land owned and operated by the County. This creek carries untreated sewage, trash, and excessive amounts of sediment that ultimately discharge into the Tijuana River without treatment. These conditions also create localized flooding at Monument Rd where existing culverts are unable to reliably pass trash and sediment and become blocked. Temporary remediation efforts are ongoing to address issues related to the transboundary flows, however, permanent solutions are needed. Currently, the County dredges Smuggler’s Gulch upstream of Monument Road approximately once a year and removes an average of 15,000 cubic yards of trash and accumulated sediment per dredging event. The City of San Diego also regularly dredges the channel downstream of Monument Road. The County’s and City’s dredging efforts are not long-term solutions because the area can quickly fill with sediment and trash after a Page 3 of 11 TIJUANA RIVER VALLEY – SMUGGLER’S GULCH IMPROVEMENTS single large rain event. Moreover, these dredging efforts occur in sensitive habitats and require Clean Water Act Section 401/404 Permits that limit dredging activities to occur from September-November to avoid impacts to threatened and endangered species like the least Bell’s vireo. There are also temporary trash booms currently installed within Smuggler’s Gulch that have proven effective at capturing trash. However, these trash booms were not designed for permanent installation and do not control sediment. Despite the current efforts to capture sediment and trash, there is still chronic flooding in the area where Smuggler’s Gulch crosses Monument Road, which impacts public health and safety. As such, there is a need to install permanent infrastructure to provide sediment and trash capture functions. Installing a maintained sedimentation basin at this location will provide an additional opportunity to capture and divert flows of sewage contaminated waters during the dry season that may not be captured within the existing IBWC diversion system. The proposed project, consisting of a permanent sediment basin and trash booms, will provide an effective long-term solution that will, as long as it is routinely maintained, remove sediment and trash from the system so that these materials are not deposited in sensitive downstream areas such as the Tijuana River Estuary. The project will also reduce localized flooding by improving an existing culvert under Monument Road and reducing the amount of time that Monument Road is impassable. This will provide more reliable access