Crews will start spring flushing today.
The crew will be starting in the Grove Street, Depot Street and Hartford Ave area working towards North Main and South Main Street. The flushing will be done during the daytime hours, 7:00 am to 3:00 pm Monday thru Friday.
High flushing flow rates are needed to loosen and remove these materials. The flushing process causes the water to become very discolored for a short period of time.
We try to flush out all discoloration; however, if a customer is using water at the same time we are flushing the section of main near their home, they may get some discolored water. If this occurs, it should clear up in an hour or less.
We recommend that customers check their water before doing any laundry. If rust stains appear on washed clothing, special iron removing detergent can be obtained free of charge from the DPW Office. (WARNING: DO NOT TRY TO BLEACH OUT STAINS. BLEACH WILL SET THE STAIN AND THEREBY RUIN THE FABRIC.)
The flushing is being done using our uni-directional flushing program. The uni-directional flushing process requires that we shut down gate valves to isolate short sections of pipe to be flushed. This process decreases the likelihood of customer’s experiencing dirty water, but can affect water pressure while hydrants are flowing. Pressure drops should only occur during the actual time that hydrants are open, which is typically less than twenty minutes.
Customers should not lose all water pressure. If they do, we have a valve closed that we think is open. If residents experience a complete loss of water pressure, they should contact the DPW at 508-966-5813 immediately.
The uni-directional flushing program utilizes computer generated models and system maps. The program is set up to flush dirty pipes with water from pipes that have already been flushed out. The sections of main being flushed are fairly small and flow in the pipes is in one direction. When a flushing hydrant is opened, water comes from recently flushed (clean) mains through un-flushed (dirty) mains and out the hydrant.
There are three big advantages of uni-directional flushing: it minimizes the water needed to flush the system, it minimizes dirty water occurrences during flushing, and it gives us insight into the condition of the pipes in our underground water distribution system.
Although hydrant flushing looks like wasting water, it is not. It is critical water system maintenance. It is necessary to flush out deposits of iron & manganese. Before we installed the town wide filtration system, the water we pumped into the distribution system had elevated levels of iron & manganese. These minerals settle out over time and cling to the water main pipe walls. Flushing the water mains and hydrants removes the accumulated mineral deposits and sediment. This helps to minimize unexpected dirty water incidents and improves water system performance.
Dirty water incidents should be on the decline due to our new filtration plants, but it will take us a few flushing cycles to get all of the mineral deposits cleaned out.
Customers can call the DPW at 508-966-5813 for a daily update on the area of town where flushing will be performed. A posting of streets to be flushed is also updated regularly in this Town News section of our website.
Initial List of Streets
Hartford Ave (at Mendon Town Line)
North Main Street
Box Pond Road
Robbins Rd & Rita Lane
Rose Ave (off of Depot St)
South Main St
Mechanic St (Near the Town Center)
Rose Ave (off of Mendon St)