Water System Facts & Figures

From Mountain Top to Your Tap

From Mountain Division reservoirs, NID water flows through the Bowman-Spaulding Canal, via Fuller Lake, to PG&E’s Lake Spaulding. It is then routed down either the South Yuba Canal to Upper Deer Creek, Scotts Flat and the Nevada City-Grass Valley area, or down the PG&E Drum System along the Bear River where the water is used to generate power for NID and PG&E before supplying NID customers in southern Nevada County and Placer County.

NID Top to Bottom

The highest elevation on NID mountain watershed is the peak of 8,373-foot English Mountain which rises east of Bowman Reservoir. The district’s highest reservoir is French Lake at 6,835 feet.

The district’s lowest elevation water service is located about 100 miles to the southwest, at 150 feet above sea level, south of Lincoln in Placer County.

Highest Dams

The district’s highest dam is the rock fill-earth core dam at Rollins Reservoir, built in 1965 and standing 242 feet tall. The Jackson Meadows dam (1965) is second highest at 195 feet, Scotts Flat dam (1965) is 175 feet and the Bowman South Arch dam (1925) is 171 feet high.

Oldest Dams

French Dam, constructed in 1858-59, is the district’s oldest dam still in use. Other dams that originated in the 1800s include the Bowman Rockfill dam (1872), and Faucherie, Sawmill and Jackson, all constructed prior to 1880. In the lower division, Van Giesen Dam at Combie Reservoir is the oldest, built in 1928.

Rain and Snowfall Data

With precipitation data that dates to the 1800s, NID is a foremost source for regional weather information.

NID has been keeping weather records for Bowman Reservoir (elev. 5,650 ft.) since 1929. The 69.2-inch annual average precipitation at Bowman compares to an annual average of 56 inches at 2,700 feet near Nevada City and 52 inches at 2,400 feet in Grass Valley.

Annual precipitation is measured for the 12-month period beginning July 1 and ending June 30.
NID is a participant in the California Cooperative Snow Survey Project. District snow surveyors conduct snow surveys regularly during the winter and spring months. Data compiled in the snow surveys is used to predict water availability locally and statewide.

All About H2O: A Dozen Facts About Water

1. Water is the most common substance found on earth.
2. Of all the earth's water, 97 percent is salt water in oceans and seas.
3. Only 1 percent of the earth's water is available for drinking water.
4. Sixty percent of Americans rely on lakes, rivers and streams as their source of drinking water. The other 39 percent rely on groundwater - water located in underground aquifers and wells.
5. There are more than 200,000 individual water systems supplying water to the public in the United States.
6. Approximately 1 million miles of pipelines and aqueducts carry water in the United States and Canada. That's enough to circle the earth 40 times.
7. Seventy-five percent of a tree is water.
8. One gallon of gasoline can contaminate approximately 750,000 gallons of water.
9. It takes 1500 gallons of water to make 1 barrel of beer.
10. Each person uses about 100 gallons of water per day at home.
11. About two-thirds of the human body is water. Some parts of the body contain more water than others. For example, 70 percent of your skin is water.
12. You can survive for about a month without food but only 5-7 days without water.

(Source: American Water Works Association)