The Price River Water Improvement District has received $7 million in funding from the state's Permanent Community Impact Board for water and sewer improvement projects. PRWID General Manager Jeff Richens said half the money is coming as a grant and half as a 20-year, zero-interest loan.
The effects on customer sewer and water rates are under review by the district's consulting firm and should be known soon, Richens said.
About $2 million is slated for upgrades at the Castle Gate water treatment plant, mainly to satisfy environmental requirements on chlorine compounds. PRWID has to inject a lot of chlorine into the water leaving the plant so that there will be some chlorine remaining in the pipes at the far end of the system. While chlorine kills bacteria, it also combines with the organic material left over to form undesirable byproducts.
PRWID is now conducting a year-long program of lab work testing the effectiveness of three different methods of reducing those compounds. Researchers will have to decide which method best suits the chemical and biological characteristics of the district's raw water supply.
The water plant also needs various upgrades to bring it up to its intended capacity of 6 million gallons a day. It now runs at 4 million because there wasn't enough money 30 years ago to put in all that was necessary, Richens explained. While the flow is adequate most of the time, there is no extra capacity to keep the water flowing out if there are problems such as turbidity during runoff or heavy rains.
During a technical briefing during the hearing last fall, Cory Christiansen of Waterworks Engineers, a consultant for the district, explained that the $5 million to be spent at the sewer treatment plant would be mainly for replacement of equipment and structures that are showing signs of old age. As an example, for the past 20 years, the metal domes covering the digesters have been constantly exposed to clouds of methane and sulfur dioxide.
Under ideal circumstances, pipes carry these gases outside to be burned away. However, these pipes have become clogged over the years. This means that the gases are being vented to the atmosphere. There's also the risk that too much pressure could pop the roofs off the corroded structures, Christiansen said.