Water Clarity

Clear water being poured into a glass.

Cheyenne normally has very clear water. On rare occasions, the water may appear discolored. Below are some frequently asked questions about discolored water. 

What to do if your water is discolored?

Check outside to see if crews are using water from nearby hydrants. If they are, wait until crews have finished then run cold water from a hose or faucet for 20-25 minutes. The water should run clear.  

If the water doesn’t flow clear, call the Board of Public Utilities at (307) 637-6471. Crews can help by removing the discolored water from the water mains using a hydrant.  

Avoid using hot water or doing laundry while the water is discolored. This will prevent sediment or minerals from being drawn into water heaters or onto clothes. When water flows clear again, normal water use may resume.  



What causes discolored water? 

We listed the common causes of discolored water from activities in the community below:

Water Main Break

Water is delivered to homes and businesses through a system of underground pipes. These pipes can break due to age, corrosion, high pressure surges, defective materials or construction work. When this happens, water can flow rapidly out of the pipes. These higher flows can scour water mains, dislodging sediment or corrosion and causing discolored water.  


Dead Ends

All water systems have water mains that end due to obstructions such as road or buildings. Where these water mains end are called “dead ends.” These dead ends can collect sediment that can cause discolored or stale water.  

To prevent stale water, BOPU crews have identified where dead ends occur in our system and regularly release water from nearby hydrants to keep water fresh and remove sediment.  

Fires and Fire Hydrant Use

Fire hydrants are designed to flow a lot of water. When used by fire fighters or construction crews, they can release enough water to scour and scrub the inside of water mains. This dislodges sediment or corrosion that can cause discolored water. 

Each spring, BOPU crews will flow water from hydrants and, by using the high-water flows, intentionally scour and scrub the inside of water mains. This prepares the water mains for summer use, removes sediment and corrosion and helps protect water quality. 

At the same time, crews will test flow rates and water pressures from the hydrants. Crews provide this information to the Insurance Service Office who rate Cheyenne’s ability to suppress fires. The better Cheyenne can flow water from the hydrants, the better fire fighters can suppress fires and the lower commercial and residential insurance premiums will be.  



Construction activities that add or replace water mains can also temporarily cause discolored water. These activities disturb sediment or corrosion in the pipes.  

BOPU crews work with construction crews to minimize discolored water from construction activities. Crews require new mains be disinfected, tested and flushed prior to being put into service. 


Your Hot Water Heater

Tank water heaters can collect sediment at the bottom of the tank that can cause discolored water. Prevent discolored water by flushing tanks per manufacturer recommendations. 


Your piping

Some types of pipes, such as galvanized iron or copper can corrode over time. This corrosion can cause discolored water.  

The rubber or plastic washers in fixtures can also crumble with age and be released into the water. 

Fixtures and appliances that rapidly shut off water can cause water surges that dislodge material from pipe walls, causing discolored water.


Cross Connections in your home

Improper attachments for insecticide/herbicide sprayers or hoses attached to faucets can allow unwanted chemicals or material to be sucked into plumbing systems. See the BOPU’s webpage on Backflow for more information.