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9.C. - Page 2 of 30 to avoid pollution in stormwater will fall on private property owners and City taxpayers to greater or lesser degrees. Past iterations of the MRP set standards for large development projects to capture and treat stormwater from new and replaced roofs, parking lots, and other impervious surfaces, because runoff from these surfaces can carry contaminants such as motor oil, pesticides, pet wastes or household chemicals into creeks and the Bay. The standards were achieved primarily through Low Impact Development (LID) design that emphasizes conservation and use of on-site natural features to protect water quality and promote ground water infiltration, although the MRP does allow for mechanical treatment in high-density areas near transit facilities, such as Downtown Redwood City. Under the MRP, the City is obligated to ensure the long-term maintenance of on-site stormwater capture and treatment facilities. The City does this by entering into maintenance agreements at the time of development approval where the property owner is required to maintain the treatment facilities, and the City must conduct inspections to ensure effective operations of the treatment facilities. The MRP requires installation of capture and treatment facilities for developments of a certain size; however, the 2015 MRP sets new, higher goals for contaminant and treatment that the City is obliged to meet. In this latest version of the MRP, a new section was added for "Green Infrastructure" (GI). This new section requires that all permittees, including the City, develop a GI Plan to meet the following goal: "Over the long term, the Plan is intended to describe how the Permittees will shift their impervious surfaces and storm drain infrastructure from gray, or traditional storm drain infrastructure where runoff flows directly into the storm drain and then the receiving water, to green—that is, to a more -resilient, sustainable system that slows runoff by dispersing it to vegetated areas, harvests and uses runoff, promotes infiltration and evapotranspiration, and uses bioretention and other green infrastructure practices to clean stormwater runoff." This is a significantly different approach than traditional stormwater design that primarily focused on sizing infrastructure to capture the runoff and pipe or pump it directly to the ocean or Bay. This new GI requirement also places a large part of the burden on the City to meet the goals of the MRP, as the City is required to meet these goals whether or not there is any development. The timeline for achieving the long-term goal for reducing the levels of contaminants through GI is by 2040, with short- and mid-term targets at 2020 and 2030. Typically, the types of projects that would help achieve these long-term pollutant reductions include regional scale stormwater retention systems that manage runoff at a watershed scale, green streets that manage runoff at the city block scale, and on-site LID that manages runoff at a parcel scale. The City/County Association of Governments of San Mateo County (C/CAG) is currently developing models to determine the relative amounts of GI at these different scales needed to meet the MRP objectives. The MRP also speaks to "no missed opportunities," which sets more immediate requirements on municipalities to ensure that GI is incorporated into all appropriate projects. City staff has been evaluating currently -funded Capital Improvement Projects to determine whether City capital projects have potential for LID design elements. GI elements also need to be integrated into the City's existing long-term planning documents, including the General Plan, precise plans, and other environmental documents. Recognizing the significant cost, maintenance burden, and staff time implications of this new MRP requirement, C/CAG is supporting its member agencies with GI Plan development by creating model GI City of Redwood City 1017 Middlefield Road, Redwood City, CA. 94063 Tel: 650-780-7000 www.redwoodcity.org 280