Low Impact Development prevents stormwater runoff and keeps pollutants out of our creeks.
Stormwater, or water runoff generated from rain, that is not absorbed into the ground accumulates debris, chemicals, and other polluting substances as it drains to the Pacific Ocean. Polluted stormwater negatively impacts the water quality of the creeks and river, is a significant public health concern, and is a threat to plant and animal life in the watershed. Furthermore, development of land typically increases the impervious surface on the land and decreases stormwater infiltration to the soil. Stormwater then flows faster across the land causing erosion, flooding, and hydromodification of creeks.
Low Impact Development (LID) aims to mimic the hydraulic function of an undeveloped site by capturing, treating, and infiltrating stormwater as close to the source as possible using small landscape-based features throughout the project site.
Download the LID Technical Design Manual
Visit the City of Santa Rosa LID Technical Design Manual website.
History of LID in Sonoma and Mendocino Counties
National Pollution Discharge Elimination System (NPDES) permits outline allowable and restricted activities required to prevent pollution and maintain high-quality stormwater discharges to waterways. The local NPDES Municipal Separate Storm Sewer System (MS4) Permit, among many things, requires agencies to regulate land development and retrofit projects within their municipal boundaries.
In August 2011, the City of Santa Rosa, County of Sonoma, and Sonoma County Water Agency published the Stormwater Low Impact Development Technical Design Manual (2011 LID Manual). The 2011 LID Manual provides technical guidance for design strategies (Best Management Practices, or BMPs) to mitigate negative water quality impacts of land development and retrofit projects.
Since that time, the Cities of Cloverdale, Cotati, Healdsburg, Rohnert Park, Sebastopol, and Ukiah, and the Town of Windsor, have adopted the 2011 LID Manual.
Locations of some example LID demonstration landscape sites are shown on the RRWA interactive map.
On March 28, 2012, RRWA sponsored a one-day workshop LID design requirements. Heaven Moore, City of Santa Rosa, led an audience of developers, engineers, architects, contractors, landscape architects, builders, storm water program managers and interested community members through the process of determining when a project is subject to LID requirements, designing LID features, navigating the new Storm Water Low Impact Development Technical Design Manual and Storm Water Calculator, submitting an application, and maintaining an LID site into the future. Heaven Moore’s presentation is available below: