The Science of Water



One of the most amazing things about the EBMUD water you drink is what’s not in it. Bacteria, viruses, metals, dirt—these can all be present in the water that melts off the Sierra Nevada Mountains and meanders into rivers and lakes before EBMUD collects it, treats it and sends it to your tap.

Using ever-improving science, technology and engineering, EBMUD filters out particles from raw water, disinfects it to remove contaminants and distributes it from our treatment plants through thousands of miles of pipes to your faucet. Think about that: EBMUD produces about 160 million gallons of delicious, clean, safe water—enough to fill about 2.5 billion drinking glasses—every day.

To do that, our staff of water treatment plant operators work 24 hours a day, seven days a week running highly specialized equipment. Testing instruments detect impurities, and a sequence of steps that include aeration, sedimentation, filtration, chemical disinfection and ozonation remove the impurities or adjust the composition of the water so that when it reaches your tap, our water meets all regulatory and water quality guidelines.

Like making a cake, the recipe for water treatment is precise. And like a seasoned baker, EBMUD continually tweaks the formula to adjust for many variables. If unaccounted for, elevation and oven temperature can affect the consistency and taste of a cake. Similarly, things like algae, which naturally bloom in hot summer months, and bacteria, which are found everywhere in nature, affect how EBMUD treats your water.

Next time you take a sip from the sink, remember—it’s what’s not in the water that makes it so wonderful.

Did You Know?

Teams of chemists, analysts and microbiologists perform more than 20,000 laboratory tests each year to ensure your drinking water is safe.

When you pay your water bill, you invest in necessary work to monitor water quality and maintain and improve critical infrastructure. Learn more about EBMUD’s budget and rates that take effect July 1, 2020 at