Is Denver water safe to drink?

June 18, 2025 5 min read

Denver, Colorado, the “Mile High City,” boasts many reasons to visit: From the craft breweries to three major colleges to a booming arts scene, Denver is home to not only its residents, but to college students, tourists, and commuters working within the city. With over 1.5 million people getting their water from Denver’s water supply, it is crucial to know what is inside their water.

Origins of Denvers’s water supply

Since Denver is surrounded by mountains, its water supply is made up of 100% surface water. Denver gets its water from rivers, lakes, streams, springs, and reservoirs, all which are fed into by snowmelt off of the nearby mountains (1). The South Platte River, Blue River, Bear Creek, and Fraser River are just a few of the many sources that provide water to Denver and the surrounding area.

Safety of Denver tap water

Denver drinking water meets or exceeds all of the EPA requirements. Additionally, the city is up to date on all of its water quality reports, even having published one for 2025. They conducted over 145,000 tests on 63,000 water samples to ensure up-to-date results for their residents (1).

Additionally, the city of Denver offers extra resources to residents whose water may be compromised, as well as bi-monthly public board meetings for concerned citizens to speak with the Board of Water Commissioners.

While Denver water meets all state and federal requirements, all water still contains small amounts of contaminants that fall under the levels set by the EPA. While small levels of these contaminants are considered safe, some people still choose to filter them out to avoid any long-lasting health effects.

Lead in Denver drinking water

Lead, for example, is a contaminant that is only detected in small amounts in Denver water, hence, meeting the federal requirements. However, lead is highly toxic, even in small amounts. According to the Environmental Protection Agency, “Even low levels of lead in the blood of children can result in: behavior and learning problems, lower IQ and hyperactivity, slowed growth, hearing problems, and anemia.” For adults, the risk of lead poisoning from low exposure to lead is less, but it is still prevalent. Adults can experience high blood pressure and decreased kidney function as a result of lead exposure.

In most of the United States, homes built before 1951 may still be using lead service lines. However, homes built as recently as 2014 in Denver may still be using faucets and fixtures that contain lead (1). Typically, it is up to the homeowner to replace any lead service lines that are on their property, which results in the choice of continuing to use lead pipes or embarking in a costly pipe-replacement project. Denver, however, chooses to take this burden off of the consumer by offering to “replace the entire inventory of lead service lines within our service area with copper lines at no direct charge to the customer” (1). In this way, the city of Denver is combatting lead exposure, regardless of the financial commitment.

Disinfection byproducts in Denver drinking water

Other contaminants that can cause harm despite them being under the legal limits are disinfection byproducts: total trihalomethanes (TTHMs) and haloacetic acids (HAA5s). Both of these compounds “form when water disinfectants such as chlorine or ozone react with other naturally occurring chemicals in the water” (2). It is necessary to disinfect water supplies to kill off dangerous bacteria, but it is not without its risks. For example, total trihalomethanes are linked to kidney, liver, and colon cancer. More research is still being done on the effects of both HAA5s and TTHMs, but both are thought to be carcinogens, with children and pregnant women being the most at-risk groups (2).

Currently, the maximum contaminant level for TTHMs in a drinking water supply is 80 parts per billion. In 2024, levels of TTHMs were detected ranging from 16.4 to 64.7 parts per billion (1). HAA5s ranged from 7.7 to 37.2 parts per billion, with the maximum contaminant level set at 60 parts per billion.

Aluminum in Denver drinking water

Aluminum is a contaminant not currently regulated by the EPA. That being said, the EPA still sets a secondary maximum contaminant level, which is a non-enforceable recommendation of the amount of a contaminant that can be found in the water before it starts to pose aesthetic issues. Most people are exposed to aluminum daily, as small amounts of aluminum are always present in the air and in food and drinking water (3). It is typically expelled in urine without any issues.

The demographic most susceptible to health effects of aluminum are adults and children with kidney disease, since kidney disease prevents most aluminum from being removed through urine. Excess aluminum in the body can lead to bone and brain disease.

The average amount of aluminum detected in Denver water is 39.5 parts per billion. The secondary maximum contaminant level ranges from 50-200 parts per billion (1). While most demographics do not need to worry about excess aluminum in their body, people with kidney disease should take extra precautions to filter their water while in Denver.

How to remove harmful contaminants from your water

For people who want to take the extra precaution of removing these contaminants from their water, the most effective method would be filtering the water. In order to do so effectively, make sure you use a water filter that is independently lab-tested to remove the specific contaminants you are concerned about. For example, Seychelle’s Gen 2 Dual Regular Water Pitcher is tested both nationally and internationally to remove chemical contaminants, like TTHMs, and inorganic contaminants, like aluminum and lead, to ensure your water is safe to drink, every time.

The Wrap-Up

Denver Water does a thorough and effective job in removing harmful contaminants from its water supply. They also provide resources to ensure no resident is at risk of lead contamination, despite the cost. Like any water supply, however, there are always traces of contaminants that are not fully eliminated. In these cases, some people prefer to filter their water to remove these contaminants completely. For a tried and true method to do so, shop Seychelle.

Frequently Asked Questions

Does Denver water have PFAS?

Denver Water tests regularly for PFAS, but all detected levels of PFAS are well below the standards set by the Environmental Protection Agency.

Is there lead in Denver water?

Lead is detected in Denver’s water supply at a level well below the national action limit, and in most cases it will not lead to human health effects.