Ketchum has discovered that its water reuse disinfection system isn't certified, as originally thought, and will need to undergo a $99,000 study to show it meets Idaho Department of Environmental Quality's standards.
Steve Hansen, Ketchum Utilities Department manager, told the City Council Monday that the system was installed in 2005 and thought to be a certified model. However, he said, it was discovered in March that the ultra-violet-light system, although similar to the state-certified model, has wider lamp spacing.
"We had no idea they made more than one model," Hansen said.
To pass the test, the system must be able to disinfect 3 million gallons of reuse water per day, much more than Ketchum and Sun Valley need. Hansen said current demand calls for between 1.25 million and 1.75 million gallons a day.
Hansen expects the system to pass the test. However, Councilman Baird Gourlay questioned, what would need to be done if it fails the test?
Hansen said, in that case, two much more expensive options would then be up for discussion to meet Idaho's 3-million-gallons-a-day standard.
The first option would be installing a second UV system in addition to the existing system, costing about $440,000. Ketchum's other choice would be installing chlorination equipment and storage as a second form of disinfection, which would run a bill between $1.5 million and $3 million.
Since the $99,000 test wasn't included in this year's budget, Hansen said construction of the planned reuse pumping station would have to be postponed until the 2010-11 fiscal year, a $120,000 cost.
"It is important to move forward with the validation study first," Hansen said, "as its outcome will affect the next steps related to construction of the pump station."
Trevon Milliard: tmilliard@mtexpress.com
