Treated Water

From the Mountain Snowpack to Your Home

N.Auburn Water Treatment Plant

Through the years, NID has changed with the communities it serves. The district continues to supply irrigation water, as it has since the 1920s, but today’s demand is for piped and treated drinking water.

Our location near the mountain snowpack, source of our water, helps to preserve a fresh, clean tasting water that many of our customers believe is among the very best in California.

NID’s treated water service areas are located in and around Grass Valley and Nevada City, Banner Mountain, the Glenbrook Basin, Loma Rica, Alta Sierra, Lake of the Pines, Penn Valley, Lake Wildwood, Smartville and North Auburn.

Generally, treated water is available in the more populated areas. It can be very expensive to extend treated water main lines into rural areas where there are few customers to share the costs. In recent years, the district has been successful in working with local property owners to form local water quality improvement districts.

The transition to treated drinking water began in the late 1960s and early 1970s when NID constructed its first water treatment plants. Today, the district operates a network of six modern water treatment plants in Nevada and Placer counties and a small seventh plant that serves the Smartsville community in the Yuba County foothills.

Nevada County Water Distribution Operators

NID presently produces about 3 billion gallons — approximately 9,000 acre-feet — of treated drinking water per year. The district’s treatment plants are operated by state-licensed and certified technicians. Water treatment processes include chlorination, coagulation, flocculation, sedimentation and filtration.

The district operates a state-certified water laboratory where water samples from throughout the district are tested regularly.

NID treated water meets and exceeds standards set by the California Department of Public Health. As required by State law, NID produces an annual water quality report, the Consumer Confidence Report, that is posted on the District’s website.  Please see the right hand column of this page for a link to the report.

NID’s flushing program is conducted annually in the winter months and is designed to keep treated water pipelines clean and ensure a fresh, high quality water supply
Today, most new customers apply for treated water service. Among existing customers, three of every four use treated water. Average household use is about 400 gallons per day.


NID Water Treatment Plants

Plant Capacity (million gallons per day)
Capacity Charge Study 

Loma Rica 8.3 Elizabeth George 18.0 Lake Wildwood 4.0
North Auburn 6.0 Lake of the Pines 5.0 Cascade Shores 0.34
Smartsville 0.085



View Current Treated Water Rates