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Water Treatment Plants

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An NID  supervisor monitors water quality.

Water treatment is any process that improves the quality of water to make it appropriate for a specific end-use. At NID, it’s for drinking and household use. 

The District treats and distributes more than 3.1 billion gallons of surface water each year.

This wasn’t always the case. In fact, in the early days of the District -- when raw water was just for irrigation -- a popular expression was that NID was short for “Not Intended to Drink.”

Today, six plants treat water to standards that exceed state and federal public health standards. Read NID's Water Quality Report 

All of the District's treated water originates as the Sierra Nevada snowpack, originating at the Middle and South Yuba Rivers, the Bear River, the north fork of the North Fork American River, and Deer Creek.

Read about NID's water treatment plants:

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In 1952, District officials were discussing treated water with the state after homeowners connected their properties to irrigation ditches and were using untreated ditch water for household use, including as drinking water. State regulators were concerned about public health and needs for filtration and chlorination.

Initially, in 1957 and 1958, NID placed chlorinators on domestic supply stations along the ditch systems. At one point, the District operated 19 chlorination stations, which provided disinfection to water supplied to about 2,000 people in a 75-square-mile area.

Yet, the need for high-quality drinking water became clear with time as the District population continued to increase. By the early 1960s, NID had 3,490 domestic customers and 1,238 raw water customers. When, in 1966, the state issued a mandate requiring a Treated Water Master Plan as well as plans for financing the work, the District was prepared to respond.

Throughout the 1970s the District invested $8 million to expand treated water service. NID’s first modern water treatment plant was built on Banner Mountain near Nevada City. Funding for the $1.3 million plant was spearheaded by local business leader Elizabeth L. “Betty” George, who was serving as president of the Sierra Economic Development District (SEDD). The original water treatment plant, named in her honor, was dedicated on May 27, 1970. When it began operation, the plant supplied 2,200 customers.

At the same time as the Elizabeth George Water Treatment Plant was coming online, NID was building a second plant off Locksley Lane in North Auburn. George was integral in securing a $1.3 million grant from the SEDD to construct the North Auburn Water Treatment Plant.

By 1980 NID was operating 15 water treatment plants of various sizes to serve its growing and scattered domestic service areas. Later, operations were consolidated to five modern treatment plants (and a small satellite plant at Smartsville), with several interties that provide backup supplies in case of emergency or operational needs.

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