Clearwell and Backwash Pump Station Replacement Project

The clearwell and backwash pump station replacement project at West Parish Filters Water Treatment Plant will replace aging infrastructure that is beyond its useful life. Funding for the $25.08 million dollar project will be aided by a subsidized low-interest loan through the state’s competitive Drinking Water State Revolving Fund (DWSRF) program. Through the DWSRF program the Commission will be able to finance the project cost at the lower-than-market-rate of 2%. In addition, in early 2022 the Commission received a $4.96 million grant in the form of loan forgiveness for this project from the Clean Water Trust.

Clearwell Replacement

The clearwell at West Parish Filters serves to store filtered water for backwashing (cleaning) the rapid sand filters and for other plant processes. The existing clearwell, which was constructed by converting slow sand filter chambers in 1925, is prone to issues related to structural integrity and infiltration. The new clearwell will be an underground concrete structure of two cells with a total storage capacity of one million gallons. The two cells will provide for redundancy so that maintenance can take place.

Backwash Pump Replacement

Additionally, backwash pumps located at the water treatment plant will be replaced. The two existing backwash pumps are used to backwash (clean) the rapid sand filters. The pumps are obsolete, with no availability of replacement parts or service manufacturers.  The two backwash pumps and related systems will provide critical improvements, including increased horsepower, energy efficient motors and controls, and much needed redundancy. 

The project marks the beginning phase of construction of significant upgrades to West Parish Filters, which will modernize the drinking water treatment plant to ensure service reliability and regulatory compliance into the 21st century.

These backwash pumps dating from the 1970s will be replaced with modern, redundant backwash pumps.

Winter 2022 Project Update

Demolition of the 1925 slow sand filters commenced in December 2021. This will be the location of the new clearwell.

Watch a time-lapse video of the action:

The slow sand filters are being demolished to make room for the new clearwell.

Demolition of the slow sand filters