Unidirectional Water Main Flushing (UDF) is gaining popularity across North America to improve operations, enhance the water system and improve service standards. Water main flushing has long been considered an effective method to remove unwanted tastes, odors or discolorations of the water, and to improve chlorine residual. UDF, a specific type of water main flushing, provides greater cleaning and uses less water than conventional flushing. This article focuses on the implementation of a UDF program, and implementation considerations are discussed for program planning and field activities.UDF isolates each pipeline to create flow in a single direction to quickly and efficiently clean the pipe. By concentrating flow, UDF creates higher velocities that are better able to clean the pipe. The cleaned mains may have improved water clarity or color, reduced turbidity and improved chlorine residual.
By using less water, UDF can be an important component of a water use efficiency or conservation program. UDF is typically performed in a set sequence to make sure a clean source of water is always used. In general, flushing should begin from a clean water source and flush from larger to smaller pipes. Flushing pipe lengths are limited to maintain efficient and safe execution, typically to approximately 1,500 ft. Minimum pressures should be maintained within the system always.
The major disadvantage of UDF is the planning needed to develop the flushing program, as well as additional crew time that is necessary to inspect the required valves and hydrants prior to the flushing. It may also require more hydrants to be flushed than in a conventional program.
This is where Wachs Water Services can assist by utilizing UDF activities as part of valve exercising and hydrant testing programs.
For more information on how to get started with a UDF plan to suits your community’s needs, contact us today at 800-525-5821; firstname.lastname@example.org