Every day in the city of Sacramento, an average of 80 million gallons of drinking water are produced – the equivalent of about 120 Olympic-sized swimming pools.
However, most people don’t know where their drinking water comes from or how goes from a raw untreated source to water that is clean and safe to drink.
That’s the job of the City’s Department of Utilities, which produces nearly all drinking water that city residents and businesses use.
Where does drinking water come from?
About 80 percent of Sacramento’s water supply comes from the Sacramento and American rivers.
The Sacramento River collects water as it travels from far northern California.
The American River collects water mostly from the Sierra Nevada mountain range in the form of snowmelt, which is stored in reservoirs, such as Folsom Lake.
The remaining 20 percent comes from groundwater wells across Sacramento.
“We are fortunate to be at the confluence of many sources of drinking water, like the Sacramento and American rivers, as well as a basin of groundwater wells,” said Pravani Vandeyar, director of the Department of Utilities.
That water is pumped into treatment facilities that make it safe for people to drink.
How is drinking water made safe?
Sacramento has two major water treatment plants: the Sacramento River Treatment Plant, which is near I-5 and Richards Boulevard, as well as the E.A. Fairbairn Treatment Plant, which is near Sacramento State on the American River.
“People often notice our water intake structures on the river, but don’t know what they’re used for,” said Vandeyar. “They are large, wing-shaped structures that reach into the river and pump out water.”
The intake structures pump raw water from the rivers, which goes through a treatment process to help ensure it is free from harmful material, including sand, silt, bacteria and viruses.
Raw water goes through several steps at the treatment plants to ensure that it is safe to drink:
- Water flows through a “grit” basin where heavier particles sink to the bottom so they can be more easily removed.
- A process called “flocculation” helps smaller particles clump together so they can be removed.
- Water then moves into “sedimentation” tanks, which remove 85 percent of particles left in the water.
- The water then goes through filters made of a hard coal, called anthracite, and sand to remove even smaller particles.
- Chlorine is added to disinfect the water from viruses and bacteria.
- Lastly, water is stored in reservoirs until it is ready to travel through the water distribution system and into homes and businesses.
How does drinking water travel to homes and businesses?
More than 1,600 miles of pipes carry treated water to homes and businesses in the city of Sacramento.
These pipes are operated by staff who routinely perform tests, repairs and maintenance on the system.
How does the City ensure water quality remains high?
A team of experts perform water quality tests around the clock, every day of the year.
Most testing focuses on microbial pathogens, which can cause illness and pose a serious public health risk.
There are 75 active testing locations where staff monitor for 121 different contaminants, including lead, arsenic and mercury.
The City maintains a water quality data website that provides updated information on contaminants that are tested for.
The entire drinking water process is supported by many teams and different types of staff, such as chemists, machinists, electricians, industrial control technicians, and engineers.
“As is always the case, we work around the clock to ensure drinking water meets or exceeds all state and federal regulations,” said Vandeyar.