Water Utilities

​Water Quality Information

Click here for current and past Drinking Water Quality Reports

Dallas' water supply

Dallas currently obtains water from area reservoirs: Lake Ray Hubbard, Lake Lewisville, Lake Grapevine, Lake Ray Roberts, Lake Tawakoni and Lake Fork. We also have plans to use Lake Palestine in the future when water demands increase. All of Dallas' water supply comes from surface water (water from reservoirs or rivers). We do not use any ground water (water from wells), although Dallas does sit atop an aquifer.

How drinking water is treated

DWU uses chemical treatment, settling, filtering and disinfection to purify drinking water. The chemicals we use include: chlorine and ammonia (which combines to make chloramine) or ozone to disinfect the water; lime and iron sulfate to remove suspended solids in the water and for corrosion control; activated carbon to control offensive tastes and odors; and fluoride to help prevent tooth decay. We use chloramine instead of chlorine to protect the health and safety of our citizens. Studies have shown that using chlorine by itself can cause a reaction in the water that leaves byproducts called trihalomethanes. Some studies indicate that trihalomethanes could be harmful if consumed in large quantities over long periods of time. Dallas water is considered non-corrosive, which means that it is less likely to leach lead from pipes than water that is corrosive. The combination of our treatment processes and the non-corrosive nature of Dallas water results in exceptionally high quality, safe drinking water. In fact, in 1991, DWU won the Environmental Protection Agency's Region 6 Environmental Excellence Award for Public Water Supply. Recently, Dallas was notified that it will again receive this prestigious award. That means that Dallasites are drinking some of the best water in five states: Texas, Arkansas, Oklahoma, Louisiana and New Mexico.

Is Dallas' drinking water safe?

You bet it is. Dallas water meets or is better than all standards set by the state and federal governments. The State of Texas has designated Dallas a "Superior Public Water System," the highest rating given by the state. Dallas has received recognition from the Environmental Protection Agency for its quality water supply. To make sure the water is safe, DWU tests the water 40,000 to 50,000 times every month, including tests for many more chemicals than government standards require. If you are concerned about your water quality, you may request more information or a free water quality test. Call 3-1-1.

Where does it go after it is used?

Used water (also known as wastewater or sewage) is pumped through the wastewater system to one of our two wastewater treatment plants. The water is then cleaned and returned to the Trinity River, where it flows downstream and is used by other cities. You may be surprised to learn that the treated wastewater we return to the river is much cleaner than the water we take out of the river upstream to purify for drinking water. We consistently meet stringent state and EPA wastewater standards and have won awards for our wastewater treatment facilities and operations.

Why is it important to protect and conserve water?

You may remember learning about the water cycle when you were in school. If you understand the water cycle, then you understand we are using the same water that dinosaurs used when they roamed the earth millions of years ago. We can never destroy water, we can only change its form. However, we should use it wisely. Water purification is expensive and pumping water through the pipes consumes a large amount of electrical energy. The dirtier the water is, the more expensive it is to clean. This explains why the wastewater portion of your water bill is more expensive than the water portion. Another good reason to conserve is that water isn't always available when or where we need it. While North Central Texas was experiencing the worst flooding in its history in the late 1980s and early 1990s, California was experiencing the worst drought in its history. It just makes sense to protect our water supply. And you can help us do that by learning how to conserve water and helping prevent water pollution.