TAR RIVER RESERVOIR WTP FILTER REHABILITATION
GR&S’ scope of work involved conducting a backwash analysis of the existing system for the sizing and replacement of air release valves. Once the backwash pumping rate was calculated, a new 4” deep-well air release valve was installed along with the replacement of three – 2” air release valves. An 18” check valve on the backwash pump was also removed and replaced.
GR&S removed six existing 20” influent valves with actuators and replaced with new valves and actuators.
In order to accommodate the City’s requirement for the WTP to remain in an operating capacity, GR&S performed filter rehabilitation one at a time. Work progressed to removing filter media (gravel, sand, anthracite) and solid porcelain spheres in the Wheeler bottom and plenum from each of the six filter cells. Filters and plenums were cleaned and inspected. Any considerable filter damage was repaired, prior to the installation of new retroliners and PWI’s. After PWI installation, new media was installed and disinfected. Bac-T’s passed and new filters are in operation.