West Slope Stormwater
Resources Planning


El Dorado Water Agency, in collaboration with El Dorado County and the City of Placerville, is implementing its Stormwater Resource Plan (SWRP) for the West Slope of El Dorado County. The West Slope SWRP is a strategic and comprehensive watershed-based document that summarizes a renewed approach to watershed resource planning and stormwater runoff management in the county.

While early regulatory efforts focused on controlling pollutants and implementing best management practices (BMPs), current regulatory decisions also emphasize holistic strategies that will result in multi-benefit projects and programs while concurrently managing pollution.

The West Slope SWRP was developed in accordance with SB 985, enacted in 2014 which amended the Stormwater Resource Planning Act of 2009. SB 985 incentivized and promoted stormwater resource planning efforts that include both wet and dry weather flow management and outlined the requirements for a SWRP.

SB 985 also stipulated that a SWRP (or its equivalent) is required to be eligible for stormwater implementation grants funded from voter-approved bonds after January 1, 2014 (Water Code Section 10563, subdivision (c)(1)). A SWRP also needs to be incorporated into the appropriate Integrated Regional Water Management Plan (IWRMP). The West Slope SWRP has accordingly been incorporated in the CABY IWRMP.

Stormwater Resource Plan and Progress Reports

Annual Progress Reports

EDWA works with the other SWRP partners to produce annual progress reports and project factsheets which outline accomplishments during each calendar year of the West Slope SWRP implementation.

Stormwater Project-Specific Implementation

EDWA and its partners are implementing various stormwater projects to address the water supply-demand imbalance, reduce localized flooding, improve water quality, provide environmental protection, and support habitat enhancement. Below are projects that EDWA is actively supporting. These projects fall under resource management strategy (RMS) 6 of the Water Resources Development and Management Plan (WRDMP).

Various locations throughout Cameron Park are subject to localized flooding. EDWA and the Cameron Park Community Services District are collaborating to perform a drainage study to identify critical drainage points for commercial and residential areas in Cameron Park and potential projects for improvements and maintenance. Potential drainage improvements may include adding/replacing culverts, adding/cleaning out ditches, cleaning up local streams and creeks used for drainage, adding storm sewers and drains to areas that experience flooding, and bank stabilization on the local creeks and tributaries.

The El Dorado County Fairgrounds is a significant economic driver for the county, representing more than $13.8 million in direct and indirect spending and over 100 local jobs. But, due to chronic on-site flooding some events have been forced to be canceled. Under the Agency’s lead and through a cost sharing agreement with the County, a Feasibility Study was developed to identify opportunities for capturing, storing, and using stormwater runoff to improve flood management and better manage stormwater as a resource. The study’s recommended alternative incorporates technology that captures and uses stormwater on-site, treats impervious runoff, provides groundwater infiltration, incorporates drainage ditch enhancements, reduces runoff, and prevents nonpoint source pollution. A detailed drainage study for the recommended alternative followed by design and engineering, compliance, permitting, and construction.

The Town of El Dorado also experiences occasional flooding on a segment of Pleasant Valley Road along Slate Creek when there is an excess amount of runoff. This project will mitigate flood risks and help reduce the risk of local water supply deterioration as well as road and drainage infrastructure failure. Improvements could include increasing culvert capacity or placing grass swales along Pleasant Valley Road to create a stormwater conveyance that will treat and filter runoff into the ground before it reaches the surrounding water bodies.

Portions of South Lake Tahoe experience localized flooding especially during rain on snow events when snow berms along plowed roadways trap rain on the roads and hinder it from draining into the watershed. Improving drainage infrastructure in South Lake Tahoe will help reduce flood risks to residential and commercial property as well as reduce the overflow burden the wastewater treatment plant faces during heavy storms. Improvements could include upgrading existing infrastructure such as curbs, gutters, treatment plants, and outdated facilities as well as implementing active preventive maintenance programs.