Charleston Water System provides clean, safe drinking water that meets or exceeds all state and federal regulatory requirements.

It is continually tested, both during the treatment process at our Hanahan Water Treatment Plant and in our water distribution system, to ensure quality. We have received many awards in recognition of our commitment to providing the highest quality drinking water.

In all, our lab performs more than 4,000 water analyses per month. An annual summary of this water quality sampling is provided in our Annual Water Quality Report, which we send to all customers in the water bill each year during the month of May. Current and past reports are available to the right on this page.

Common water quality problems

Problems with water taste, odor, or color, can be caused by a variety of factors, some related to internal plumbing issues, others to Charleston Water System. Often, such issues are aesthetic concerns that don't affect the safety of the water, but they can certainly make the water unpleasant to use.

If something happens that makes the water unfit to drink, Charleston Water System will issue an immediate advisory and notify customers via the media and other means.

Here is an overview of the the most common water quality problems, and what to do:

Brown water

Some water pipes can accumulate deposits on the inside of the pipe wall. Most of the time, this is not a problem, but changes in water pressure caused by construction activity or the use of fire hydrants can cause these deposits to break loose and dissolve in the water, resulting in discoloration.

Charleston Water System routinely flushing our water mains to remove these deposits, and this can sometimes cause temporary discoloration. Fire departments also test hydrants, which can also cause problems.

Although unpleasant, it's temporary and not harmful. Our crews can eliminate most of the discolored water through fire hydrants, but if you have discolored water, you should let your faucet run until the water appears clear. If the problem persists, contact us by calling 727-6800 or send us an e-mail.

Rotten egg odor

Recently, we have received a number of complaints about water having a sulfur or rotten egg odor. After some investigation, we discovered this is usually caused by water heaters.

If you have a large water heater and you're not using the hot water often enough to circulate it through the tank, hydrogen sulfide producing bacteria can begin to grow in the tank, resulting in a rotten-egg odor when you use warm or hot water.

You can eliminate this by draining and flushing your hot water heater. Follow the manufacturers instructions. Most manufacturers recommend flushing your tank at least once a year.

If your water heater isn't to blame, there are two other potential causes:

Unused sinks
If a sink is not used for a long period of time, the standing water that's supposed to stay in the S-trap (the pipe under the sink) to keep sewer odors from drifting back through the sink drain can dry up. This can result in unpleasant odors.

Food disposal in kitchen sink
Sometimes decaying food particles in the kitchen sink disposal can cause odors that are mistakenly associated with water from the kitchen faucet. Running ice cubes or and lemon slices and baking soda in the disposal will clean the disposal and eliminate the odor.

Pink or black growth on faucets, around drains, etc.

Pink staining and black growth are both are caused by airborne microorganisms that thrive in warm, moist areas such as bathrooms and laundry rooms—not by anything in the water.

Some people observe a black gunk on their faucets and in toilets. This is a type of mold that grows rapidly in dark, humid places, producing a black string-like material that can break loose and hang from faucets.

Pink film that typically appears around drains is caused by airborne bacteria that also thrive in moist areas, such as sinks, toilets, and bathtubs.

The best way to combat both is frequent cleaning with a bleach solution. Make sure you have proper ventilation in bathrooms, and repair dripping faucets to keep the area around drains dry.

Earthy-musty taste in the Spring (and sometimes Fall)

It is a common misconception that clean water has no taste or smell. In fact, many things affect how water tastes, including where it comes from, mineral content, weather and temperature, the treatment process, etc.

Each Spring, Charleston Water System's water develops what's most often described as an earthy or musty taste and odor. This does not affect the healthfulness of the water—just the taste and smell.

It's caused by warm temperatures and increased sunlight, which promote algae growth and water turnover in our primary water supply, the Bushy Park Reservoir. These organics produce a harmless, but sometimes unpleasant, taste and odor that can be detected by the human nose at very small levels.

We can minimize the taste and odor by adjusting our treatment process, namely by adding activated carbon to our water, which adsorbs the compounds responsible. Each Spring, we monitor taste and odor complaints closely and begin adding carbon when the complaints reach a certain threshold. Our lab also conducts smell tests frequently to try and detect when the taste and odor event begins.

For more information, read a press release about Springtime taste and odor. To report a taste and odor concern, e-mail us or call our Customer Service Center at 843-727-6800.

Request a water quality test
If you have a water quality concern or would like to request a water quality test, please call our Customer Service Department at (843) 727-6800 or send us an e-mail.

Lead testing
Charleston Water System reduces the corrosiveness of our water during the treatment process, which prevents lead from old plumbing from leaching into your water. However, if your home has old plumbing and/or solder, and you would like to test your water for lead, we offer testing free of charge. Just pick up a testing kit at our downtown or North Area office locations.

Learn more about lead and drinking water