Domestic water is currently supplied by four groundwater wells owned and operated by the District and located throughout the Kirkwood Valley with a combined peak production of 225 gallons per minute. The existing storage system includes tow storage tanks with a capacity of 950,000 gallons. The District’s water distribution system consists of approximately five miles of pipelines ranging from six to ten inches in diameter.
The applicable drinking water standards for the District’s potable water system are provided in the California Domestic Water Quality and Monitoring Regulations, Title 22 of the California Administrative Code. These regulations incorporate the requirements of the U.S. Environmental Protection Agency in conformance with the Safe Drinking Water Act (PL 93-523). The standards specify water quality sampling frequencies and location as well as maximum concentrations of chemical constituents and are continually revised and amended. The District operates under a Water Supply Permit issued by the State, Department of Health Services.
Total water demand for the District varies from 12 – 15 million gallons per year at the current 50% build-out of the community. The District is in the process of exploring its existing potable water sources and capacity versus its projected future potable water needs. The District anticipates that existing water source production will not meet anticipated potable water needs at full community build-out. The District has plans to explore the ability to develop additional water sources to augment the District’s supply to provide the capacity and reliability necessary to maintain Water Enterprise service through anticipated long-term growth.
The District provides sanitary wastewater collection, treatment and disposal for the community. The District’s wastewater treatment and disposal facility is regulated by permit under the jurisdiction of the Central Valley Regional Water Control Board under Waste Discharge Requirements (WDRs) Order No. R5-2007-0125. The WDRs contain monitoring and reporting requirements, which include quarterly and annual monitoring of groundwater at eight locations around the Kirkwood Valley.
The wastewater collection system consists of approximately 8.3 miles of six-inch gravity-flow wastewater collection lines and approximately 3,600 feet of eight-inch force main sewer lines. Two lift stations transfer the wastewater to the Treatment Facility. In 2001 – 2002, the Treatment Facility was upgraded from a conventional activated sludge treatment process to a membrane bioreactor, which provides tertiary treatment of collected wastewaters. The Treatment Facility process includes solids screening, flow equalization, nitrification, dentrification, phosphorous removal via chemical additions, aeration, membrane filtration, disinfection, effluent disposal via pressure-dosed leach lines, extended aeration of waste sludge, and sludge dewatering (via centrifuge).
In the fall of 2013, the District replaced the existing membranes, which had reached the end of their service life, in advance of the 2013-14 winter (peak flow) season in order to maintain reliable wastewater service for customers. The new membranes include improved technologies which will enhance overall treatment performance and service life.