If you happen to notice water gushing from fire hydrants along Southwest Parkway on Tuesday, don’t worry – the water lines between Wellborn Road and Texas Avenue are being flushed as part of our water line cleaning project.
We’ll start flushing about 8 a.m. by opening and closing carefully selected hydrants and valves, flushing the water at high enough velocities to scour the water line. If you’re driving east on Southwest Parkway, you may notice significant flowing water in the roadway, so please be careful.
During the flushing process, you may experience discolored water or a short-term decrease in water pressure. Discoloration is caused by naturally-occurring sand, sediment, or iron that is scoured from the pipes. These solids are not harmful, but they may cause your water to taste different.
If you have discolored water, run the cold water in your kitchen, bathroom or an outside faucet to flush your water lines. If that doesn’t work or you lose your service entirely, call our 24-hour Utility Dispatch hotline at 855-528-4278. For the fastest response, please have your CSU account number ready.
About Unidirectional Flushing
Tuesday’s flushing continues the Unidirectional Flushing (UDF) process we started in October 2012 with large-diameter water lines. Routine water line flushing is done on a small scale in response to water quality complaints, but UDF is a proactive and large-scale approach to improving quality. This technique improves water quality by removing sediments and stale water, and improves the disinfectant residual and water clarity, resulting in long-lasting water quality improvements throughout the system.
“How does Unidirectional Flushing work?”
Unidirectional flushing involves opening specifically-selected fire hydrants and closing specifically selected valves under controlled conditions to scour the inner surface of water distribution pipes. The scouring process helps to remove corrosion scale and sediment that accumulate naturally over time. If left in place, these deposits could degrade water quality and restrict water flow.
“Aren’t College Station’s water lines clean already?”
Water mains are designed to handle fire flow, which may be several times larger than domestic or commercial water flow. Consequently, the rate that water flows through pipes is normally fairly low, which can cause sediment to settle on the bottom. The problem may be more significant where there are dead-end pipes or areas of low water use. Sediment buildup reduces the amount of water that can flow and can be a source of color, odor and taste problems. Flushing the pipes at high velocities removes most of the settled substances and discolored or stale water.
“Isn’t all this flushing a waste of water?”
Large quantities of flushed water on the ground may seem wasteful, but unidirectional flushing is an effective way to improve drinking water quality. Unfortunately, the velocities needed to scour water lines make it impractical to capture the flushed water for reuse. Unidirectional flushing is a deliberate, planned process specifically designed to reduce overall water usage by limiting reactionary flushing in the future.
“When will flushing be done in my neighborhood?”
Water Services will wrap up the UDF program in specific areas of the water distribution system in the coming months. Flushing normally occurs between 9 a.m.-3 p.m.
For more information, email me at jnations@cstx.gov or call 979-764-6223.
Happy Thanksgushing!

Water Resource Coordinator