Denver Water Board

The U.S. Environmental Protection Agency requires community water systems to provide annual water quality reports to their customers. These reports summarize information about water sources, detected contaminants, compliance status, and educational information.

Water Source Information: Denver's water originates from high-quality mountain snow runoff that feeds rivers, lakes, streams, and reservoirs. Denver Water's supply is 100% surface water from a watershed covering 4,000 square miles on both sides of the Continental Divide.

Mountain Water Sources: Denver Water collects from the South Platte River and its tributaries, Dillon Reservoir feeder streams, and Fraser River watershed. Water is stored in five mountain reservoirs (Antero, Eleven Mile Canyon, Cheesman, Dillon, and Gross) before traveling to one of three treatment facilities through an intricate network of waterways and pipelines.

Source Water Assessment: The Colorado Department of Public Health has completed an assessment of potential contamination risks to Denver Water's terminal reservoirs at Strontia Springs, Marston, and Ralston. Possible contamination sources include EPA Areas of Concern, wastewater discharge sites, storage tank locations, waste facilities, mining operations, industrial/commercial areas, urban developments, agriculture, forests, septic systems, oil/gas wells, and transportation corridors.

Denver Water's Commitment: Denver Water provides high-quality drinking water to 1.4 million people throughout Denver and surrounding suburbs. Established in 1918, this public agency is funded through water rates and tap fees, not taxes. Denver Water serves 25% of Colorado's population using less than 2% of the state's total water.

Water Quality Testing: Last year, Denver Water collected over 35,000 samples and conducted more than 68,500 tests to ensure water safety. The utility vigilantly protects mountain water supplies and carefully treats water before delivery.

Health Information: All drinking water, including bottled water, may reasonably contain small amounts of some contaminants. This doesn't necessarily indicate a health risk. Immunocompromised individuals, including those undergoing chemotherapy, organ transplant recipients, people with HIV/AIDS or immune disorders, some elderly individuals, and infants may be particularly vulnerable to waterborne infections.

Lead in Water: Since 1992, Denver Water has tested homes at risk for lead and copper contamination per EPA standards. The source water, treated water leaving plants, and water in the distribution system contain no detectable lead and only trace copper amounts. Lead can enter water through household plumbing. Homes built before 1951 may have lead service lines, while homes built before 1987 might contain lead solder. Flushing taps for two minutes after water has been sitting can help reduce potential lead exposure.

Cryptosporidium and Giardia: Denver Water has tested for these microorganisms since the 1980s and has never detected viable indicators in treated drinking water. These organisms can cause gastrointestinal symptoms and are typically found in Colorado's waterways due to animal waste in watersheds. Denver Water removes these organisms through effective filtration, with Giardia also eliminated through disinfection.

1. How often is my water tested?
2. What causes water hardness in Denver?
3. Should I use a water filter with Denver municipal water?
4. How can I check for lead in my home's plumbing?
5. What treatment processes does Denver Water use?