SHERIDAN — Conventional upgrades to the Sheridan and Big Goose water treatment plants have continued throughout the winter, Water Treatment Superintendent Tom Manolis told the Sheridan Area Water Supply Joint Powers Board at its regular meeting Wednesday.
The winter months are an ideal time to do most the major underground work of replacing pipes because water demand is low and there is no spring run-off to deal with at the plants, Manolis said. The Sheridan Water Treatment Plant was shutdown Dec. 16 and Jan. 7 in order to replace aged pipes and install a 500-pound stainless steel static mixer inside one pipe.
When one plant is shutdown, the other one carries the entire load of city and SAWS water systems. Since neither plant is running at capacity, it is possible to “amp up” one plant during the shutdown of the other plant.
“Having two plants provides redundancy,” Manolis said during his presentation to the board, adding that it is important to avoid a single point of failure when dealing with something as important as the water supply.
At the Sheridan Water Treatment Plant, crews with Fletcher Construction have dealt with a few unknowns that have made the process trickier.
“The drawings from 1966 are not as accurate as they are these days,” Manolis said.
The Jan. 7 shutdown was supposed to last eight hours but ended up lasting 30 hours after it was decided a crew member would have to descend 80 feet into a pipe located 15 feet underground to weld the static mixer into place. The crew member was tethered to a location outside the pipe and a hose was inserted into the pipe to pump air into him as he worked. Crews worked around the clock to keep the plant shutdown as short as possible.
Major work at the Big Goose Water Treatment Plant will begin next week, Manolis said, when crews will begin assembling bypass piping in order to accommodate construction of a rapid mix chamber. The Big Goose plant will shutdown three times before March 15. Manolis said all plant shutdowns will be completed before March 15, which is when run-off begins and demand for each plant increases.
Upgrades at both of Sheridan’s water treatment plants were needed to meet Wyoming Department of Environmental Quality standards and to replace aged systems.
One of the biggest benefits of the upgrades will be more accurate chemical dosing, which is being able to apply a known amount of chemical to a known amount of water, Manolis said.
Upgrades are estimated to be complete within a year.
In other business:
• The SAWS board elected new officers. City Councilman John Heath was named chairman, and County Commissioner Bob Rolston was named vice chairman. Commissioner Steve Maier was named treasurer, and Councilman Alex Lee was named secretary.
• SAWS Project Manager Dan Coughlin updated the board on the progress of the Maverick Bridge water line relocation. He said the water pipe is in place and is being used by customers. The road is open, and the project is substantially complete. Final completion will happen in the spring when the weather is more cooperative.
• The board approved a request for a time extension on a water service permit on tract 8 of the McNally Subdivision. The validity period was scheduled to end May 12, 2014, but it will now end May 12, 2016.