General Water

Lahontan Regional Water Quality Control Board’s Stormwater Program

By Patty Z. Kouyoumdjian, Executive Officer

The Lahontan Regional Water Qual­ity Control Board, known as the La­hontan Water Board, is a state agency whose mission is to protect surface and groundwater uses for current and future benefit of all Californians. The board has seven members appointed by the governor and confirmed by the Senate. Staff offices are located in South Lake Tahoe and Victorville.

Implementing a number of federal and state regulatory programs, board decisions directly or indirectly affect most all residents within the Lahon­tan Region. The Lahontan Region encompasses the Great Basin portion of California. It extends from Ore­gon south to the San Gabriel and San Bernardino Mountains and eastward from the crest of the Sierra Nevadas to Nevada. Within San Bernardino County, numerous board actions are taken to protect and improve the state’s waters. This article’s focus is the Stormwater Program.

Stormwater Program Requirements

Statewide general orders (e.g. permits) exist for three main stormwater pro­gram categories; industrial, construc­tion, and municipal. Permit links are on the State Water Resources Control Board website at: http://www.waterboards.ca.gov/water_issues/pro­grams/stormwater/. Coverage under all permits is obtained through the SMARTS database, which can be ac­cessed at that website.

Construction Activities

Construction permit coverage is re­quired for any land disturbance great­er than one acre. Note that disturbed area, not project size, is the governing factor. Additionally, project compo­nents forming a larger plan of devel­opment must be considered together. Minimizing sediment transport im­pacts is the primary permit objec­tive. For each project a site-specific Stormwater Pollution Prevention Plan, or SWPPP, must be prepared by a Qualified Stormwater Develop­er. It must identify appropriate Best Management Practices, or BMPs, that will be installed and maintained by a Qualified Stormwater Developer for both the construction and post-construction periods.

Porous concrete makes up part of a new parking lot in Victorville at Valley Hi Toyota (darker pavement)

Porous concrete makes up part of a new parking lot in Victorville at Valley Hi Toyota (darker pavement)

The water board’s key objective is en­suring that effective post-construction BMPs are in place at the time permit termination is granted. The permit requires that the post-construction runoff is equal to or less than pre-construction runoff and that runoff does not cause downstream effects, including erosion or modification of drainage patterns, swales or stream channels. A site-specific hydrology calculation must be done to verifythat the post-construction BMPs will be effective at meeting this requirement. While there are a wide range of BMPs that may be proposed, the Lahontan Water Board promotes BMPs appropriate to the arid high desert climate, using Low Impact Develop­ment, or LID, principles discussed below. Effective post-construction BMPs must be proposed in the proj­ect design. Numerous termination requests have been declined by the water board where post-construction BMPs were not in place. To speed the termination process, proponents should include photographs show­ing the periphery of the construc­tion site, especially runoff locations. Photographs of the interior drainage features, unless integral to post-construction BMPs such as prefabricated infiltration chambers, are less impor­tant.

Industrial Activities

Industrial permit coverage is required based on industry type or Standard Industrial Classification (SIC) codes. For manufacturing facilities cover­age is required for SIC codes 20XX through 39XX and 4221 through 4225. Permitted facilities must prepare and implement a SWPPP that identifies appropriate BMPs. The permit re­quires stormwater runoff sampling from Qualifying Storm Events. Staff has inspected many industries in the Victor Valley that have ineffective BMPs or conduct operations in or near ephemeral waterways, causing adverse effects to waters. Identifying and requesting modified practices and improved stormwater management will be the focus of future inspec­tions. The permit includes two new options for enrollees. A No Exposure Certification may be obtained if all industrial materials and activities areprotected by a storm-resistant shelter. A Notice of Non-Applicability signed by a registered professional engineer may be submitted if a facility is engi­neered to contain the maximum his­toric precipitation event or is located where there is no hydrologic connec­tion to waters of the United States.

Erosion in epheremal wash caused by concentrated urban run-off, Hesperia

Erosion in epheremal wash caused by concentrated urban run-off, Hesperia

Municipal Activities

Municipal permit coverage is re­quired for the Town of Apple Valley; Cities of Barstow, Hesperia, and Vic­torville, and portions of the County of San Bernardino. In addition to con­trolling pollutants in stormwater run­off from municipal activities (shops, yards, streets, etc.), municipalities must adopt ordinances providing le­gal authority to control pollutants (in­cluding sediment) into and from the municipal storm system. Other program areas include public outreach and education, illicit discharge identi­fication and elimination, construction site controls, and post-construction BMP requirements. The permit re­quires new projects to capture stormwater from the 85 percentile 24-hour precipitation event. Effective main­tenance is the key to ensure post-con­struction BMPs continue to protect water quality.

Low Impact Development, Stream and Wetland Impacts

In the earliest project design phase, applicants should assess and evalu­ate how site con­ditions such as soils, vegetation, and flow paths should be consid­ered in the placement of buildings and impervious surfaces to re­duce adverse im­pacts to surface flow paths, water quality and wild­life habitat. Envi­ronmental docu­ments should identify how the project incorpo­rates Low Impact Development, or LID, principles to protect water qual­ity. The High Desert has unique rain­fall and stormwater runoff patterns. LID practices should be cus­tomized for each individual site to preserve pre-develop­ment hydrology by limiting impervious surfaces (i.e, pav­ing), promoting stormwater infiltration, minimizing land disturbance, and incorporat­ing structural BMPs such as pervious pavement, infiltra­tion galleries, energy dissipa­tion, etc. Water board staff have observed many older projects have radically alteredthe ephemeral wash downstream en­vironment by increasing runoff ve­locities and volumes, causing exces­sive sediment erosion and sediment deposition in lower-lying areas, bury­ing wildlife and riparian habitat. In­corporating LID principles in future new and redevelopment projects will protect and improve our unique des­ert environment and water quality for our future.

Proposition 1 Grant Funding Resources

A new opportunity to obtain storm­water project funding is available through Proposition 1 grants. This requires applications to reference an adopted Stormwater Resources Man­agement Plan that identifies projects on a watershed basis. That plan may become a component of the Mojave Water Agency’s Integrated Regional Water Management Plan and can be used to support grant requests. The water board encourages local munici­palities to cooperate and cost share in preparing this plan.

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