HYDROLOGY & WATER QUALITY INTRODUCTION This section evaluates the potential impacts of the project on drainage, flood hazards and water quality. The section was prepared in association with Schaaf & Wheeler, Inc. Schaaf & Wheeler conducted a hydraulic analysis and reviewed the proposed project drainage system as part of the preparation of this EIR. Their technical review memos are included in Appendix E. ENVIRONMENTAL SETTING IN THIS SECTION: Regulatory Setting Regional Hydrological Setting Site Stormwater Drainage Flood Hazards Water Quality Groundwater Management Regional and Local Plans REGULATORY SETTING A number of federal, state, and local laws and plans regulate activities to protect water quality and reduce flood hazard risks. The following sections summarize the principal regulations that pertain to the project site. Federal Regulations CLEAN WATER ACT The Clean Water Act (CWA) regulates the discharge of pollutants to waters of the United States from any point source, enacted in 1972. Section 401 of the CWA requires water quality certification for any activity, including the construction or operation of a facility, which may result in any discharge into navigable waters (Title 33 CFR §1341). Section 404 of the CWA requires a permit for the discharge of dredged or fill material into navigable waters at specified disposal sites (Title 33 CFR §1344). In 1987, amendments to the CWA added Section 402(p), which establishes a framework for regulating non‐point source storm water discharges TOWN OF LOS GATOS DRAFT EIR L INDA C OURT R ESIDENCES 4.3-1 JANUARY 2010 HYDROLOGY & WATER QUALITY under the National Pollutant Discharge Elimination System (NPDES). The NPDES storm water program is further described below under the “State Regulations” subsection. FEMA FLOOD MANAGEMENT The Federal Emergency Management Agency (FEMA) – a former independent agency that became part of the new Department of Homeland Security in March 2003 – is tasked with responding to, planning for, recovering from, and mitigating against disasters. FEMA is responsible for coordinating the federal response to floods, earthquakes, hurricanes, and other natural or man‐made disasters and providing disaster assistance to states, communities and individuals. FEMA administers the National Flood Insurance Program (NFIP) to provide subsidized flood insurance to communities that comply with FEMA regulations limiting development on floodplains. FEMA issues Flood Insurance Rate Maps (FIRMs) for communities participating in the NFIP, which delineate flood hazard zones. State Regulations The California State Water Resources Control Board (State Board) and the nine Regional Water Quality Control Boards (RWQCB) have the authority in California to protect and enhance water quality, both through their designation as the lead agencies in implementing the Section 319 non‐point source program of the federal Clean Water Act, and through the state’s primary water pollution control legislation, the Porter‐Cologne Act. The San Francisco (Region 2) office of the RWQCB guides and regulates water quality in streams and aquifers throughout the San Francisco Bay area, including Santa Clara County. The RWQCB implements the Basin Plan, which designates beneficial uses and establishes water quality objectives. The RWQCB also administers the NPDES permit program for storm water and construction site runoff, and is also responsible for providing permits under Section 401 of the CWA. NATIONAL POLLULTION DISCHARGE ELIMINATION SYSTEM (NPDES) Point source discharges to surface waters are generally controlled through waste discharge requirements issued under the federal National Pollutant Discharge Elimination System (NPDES) permits. Although the NPDES program was established by the federal Clean Water Act, the EPA has delegated management of California’s NPDES permit program to the State Water Resources Control Board and the nine regional (RWQCB) offices. Issued in five‐year terms, an NPDES permit usually contains components such as discharge prohibitions, effluent limitations, and necessary specifications and provisions to ensure proper treatment, storage, and disposal of the waste. The permit often contains a monitoring program that establishes monitoring stations at effluent outfall and receiving waters (California Regional Water Quality Control Board, San Francisco Bay Region, 2007). TOWN OF LOS GATOS DRAFT EIR L INDA C OURT R ESIDENCES 4.3-2 JANUARY 2010 HYDROLOGY & WATER QUALITY The 1987 amendments to the Clean Water Act (Section 402[p]) provided for the U.S. EPA regulation of several new categories of non‐point pollution sources within the existing NPDES). In Phase 1, NPDES permits were issued for urban runoff discharges from municipalities of over 100,000 people, from plants in industries recognized by the EPA as being likely sources of stormwater pollutants, and from construction activities that disturbed more than five acres. Phase 2 implementation, effective March 10, 2003, extended NPDES urban runoff discharge permitting to cities of 50,000 to 100,000, and to construction sites that disturb between 1 and 5 acres. The Town of Los Gatos is part of the Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP) that has been issued a National Pollutant Discharge Permit (NPDES) under the Clean Water Act for discharge of storm water runoff. The SCVURPPP is an association of thirteen cities and towns in the Santa Clara Valley, together with Santa Clara County and the Santa Clara Valley Water District that, share a common permit to discharge stormwater to South San Francisco Bay. Further discussion is provided below. Construction activity on projects that disturb one or more acres of soil, or less than 1 acre but are part of a larger common plan of development that in total disturbs one or more acres, must obtain coverage under the General Permit for Discharges of Storm Water Associated with Construction Activity (Construction General Permit, 99‐08‐DWQ). Construction activity subject to this permit includes clearing, grading, and disturbances to the ground such as stockpiling or excavation, but does not include regular maintenance activities performed to restore the original line, grade, or capacity of a facility. The Construction General Permit requires the development and implementation of a Storm Water Pollution Prevention Program (SWPPP). The SWPPP should contain a site map(s) that shows the construction site perimeter, existing and proposed buildings, lots, roadways, storm water collection and discharge points, general topography (both before and after construction), and drainage patterns across the project. The SWPPP must list best management practices (BMPs) that the discharger will use to protect storm water runoff and the placement of those BMPs. Additionally, the SWPPP must contain a visual monitoring program and a chemical monitoring program for ʺnon‐visibleʺ pollutants to be implemented if there is a failure of BMPs. PORTER-COLOGNE WATER QUALITY CONTROL ACT Under the stateʹs Porter‐Cologne Water Quality Control Act, any person discharging or proposing to discharge waste within the region (except discharges into a community sewer system) that could affect the quality of the waters of the state is required to file a Report of Waste Discharge (ROWD). The Water Board reviews the nature of the proposed discharge and adopts Waste Discharge Requirements (WDRs) to protect the beneficial uses of waters of the state. Waste discharge requirements could be adopted for an individual discharge, or a specific type of discharges in the form of a general permit. The Water Board may waive the requirements for filing a ROWD or issuing WDRs for a specific discharge where such a waiver TOWN OF LOS GATOS DRAFT EIR L INDA C OURT R ESIDENCES 4.3-3 JANUARY 2010 HYDROLOGY & WATER QUALITY is not against the public interest. NPDES requirements may not be waived. Acceptable control measures for point source discharges must ensure compliance (California Regional Water Quality Control Board, San Francisco Bay Region, 2007). CLEAN WATER ACT WATER QUALITY CERTIFICATIONS Under section 401 of the federal Clean Water Act, the RWQCB has regulatory authority over actions in waters of the United States through issuance of water quality certifications, which are issued in combination with permits issued by the U.S. Army Corps of Engineers under section 404 of the Clean Water Act. When the Board issues section 401 certifications, it simultaneously issues general Waste Discharge Requirements for the project under the Porter‐ Cologne Water Quality Control Act. Local Regulations and Programs The Town of Los Gatos coordinates regulating the NPDES permit with the West Valley Clean Water Program (that includes Campbell, Los Gatos, Monte Sereno, and Saratoga), West Valley Sanitation District, and Santa Clara Valley Urban Runoff Pollution Prevention Program (SCVURPPP). To reduce pollution in urban runoff to the ʺmaximumʺ extent practicable, the Program incorporates regulatory, monitoring and outreach measures aimed at improving the water quality of South San Francisco Bay and the streams of the Santa Clara Valley. As part of the NPDES permit requirements, the Program produced (and updates) an “Urban Runoff Management Plan” and submits annual work plans and reports to the Regional Board. SANTA CLARA VALLEY URBAN RUNOFF PREVENTION PROGRAM In 1990, the SCVURPPP received the first municipal stormwater permit in the nation from the San Francisco Bay Regional Water Quality Control board, which was reissued