Distribution System

Drinking water is delivered to homes and businesses through the water distribution system, a network of infrastructure that includes pipes, valves, fire hydrants, pump stations, and storage tanks. Charleston Water System has more than 1,800 miles of water mains, all of which must be maintained to ensure the water keeps flowing 24 hours a day, 365 days a year.

High-powered pumps at our Hanahan Water Treatment Plant pump water into the distribution system. Pressures leaving the plant range from 85 to 95 pounds per square inch (psi), depending on the number and type of pumps in operation. We also have several pumping stations and storage tanks throughout the distribution system to maintain pressure and meet peak water demands.

Fire Hydrants
Fire hydrants are owned and maintained by Charleston Water System, although area fire departments periodically test hydrants. Charleston Water System has more than 9,300 fire hydrants.

We do allow fire hydrants to be used for temporary water service, but this requires a special permit. For more information, please contact our Cross Connections Department at 843-727-6862.

Water Main Flushing
Over time, minerals and other deposits can accumulate inside water mains. To clean the mains and remove these deposits, Charleston Water System uses a technique called Unidirectional Flushing, or UDF.

Flushing water mains involves opening a nearby fire hydrant and discharging water from the hydrant; the high velocity of the water cleans the inside of the mains.