Appendix A Water Quality Memo - Laserfiche WebLink

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9 demonstrated that the groundwater being discharged to surface waters does not contain pollutants of concern (selenium and nitrates). Under this permit, permittees are required to monitor their discharges from groundwater extraction waste from construction to ensure that effluent limitations for constituents are not exceeded. 3.0 AFFECTED ENVIRONMENT 3.1 Surface Waters The Project area is within the Santa Ana River Watershed, which is within the jurisdiction of the Santa Ana RWQCB. The Santa Ana RWQCB jurisdiction is approximately 2,800 square miles in portions of Orange, Riverside, and San Bernardino counties and mostly consists of the 2,650-square-mile Santa Ana River Watershed. Specifically, the Project area is within the Lower Santa Ana River Watershed, which extends from Prado Dam to the Pacific Ocean. For regulatory purposes, the Santa Ana RWQCB designates watershed areas in Hydrologic Units (HUs), which are further divided into Hydrologic Areas (HAs) and Hydrologic Subareas (HSAs). As designated by the Santa Ana RWQCB, the Project area is located within the Santa Ana River HU, the Lower Santa Ana River HA, and East Coast Plain HSA (Santa Ana RWQCB 1995). The Santa Ana River extends approximately 96 miles from its headwaters to where it drains into the Pacific Ocean. The headwaters for the Santa Ana River and its tributaries originate in the San Gabriel, San Bernardino, and Santa Ana Mountains. From the San Bernardino and San Gabriel Mountains, the Santa Ana River flows through San Bernardino and Riverside Counties, then through the Prado Basin and a narrow pass in the Santa Ana Mountains. From the Santa Ana Mountains, the Santa Ana River flows southwesterly through Orange County to the Pacific Ocean. The Santa Ana River is divided into six reaches. The Fairview Street bridge crosses Reach 1 of the Santa Ana River, which defined as the portion of the river between the tidal prism and 17th Street in Santa Ana. The Santa Ana River within the Project area is a concrete-lined, trapezoidal channel and is devoid of vegetation (LSA 2018b). Intermittent flows within the Santa Ana River can be attributed to stormwater runoff, urban runoff, and treated wastewater (LSA 2018a). Beneficial Uses of Surface Waters Beneficial uses of water are defined in the Basin Plan as those necessary for the survival or well-being of humans, plants, and wildlife. Examples of those beneficial uses include drinking water supplies, swimming, industrial and agricultural water supply, and the support of freshwater and marine habitats and their organisms. The existing or potential beneficial uses for the Santa Ana River Reach 1, as identified in the Basin Plan, are: • REC-1: Water Contact Recreation (access prohibited in all or part of the river per agency jurisdiction) • REC-2: Non-Contact Water Recreation The intermittent beneficial uses for the Santa Ana River Reach 1, as identified in the Basin Plan: • WARM: Warm Freshwater Habitat • WILD: Wildlife Habitat