Environmental Services
Cleaning and Lining of Existing Water Mains
The Process
The cleaning and lining process consists of either mechanically or hydraulically scraping the inside of the pipe to remove all corrosion products or scale. Once the pipe is sufficiently cleaned and de-watered, a thin lining of cement mortar is centrifugally applied to the pipe and smoothed with a trowel. After the mortar cures, the pipe is inspected, tested, disinfected, and placed back into service. When a pipe is out of service during the cleaning and lining process, temporary service lines will be installed on the surface to provide water to all residents in the affected area.
Reconditioning water mains by this method eliminates the necessity of digging up all of the pipes to replace them, saving time, money, and the aggravation of torn up streets to the residents of Arlington County.
 | Routing machine used to drive cutter heads that clean existing water mains. Digging up of the streets is limited to access pits for the cleaning and lining equipment. |
 | Water main prior to cleaning. Flow is restricted by mineral deposits. |
 | Access pit for water main cleaning. |
 | Feed from water system to temporary by-pass lines. |
 | Temporary by-pass line (by the curb) and jumper line to water meter box. |
 | Temporary fire hydrants are placed in the by-pass water line so that water is available in event of fire. |
