More pressure, better flow

Before the sun even rose over the hills north of Ketchum one recent morning, 22 construction workers poured and smoothed concrete footings at the base of what will be two one-million-gallon water towers.

The Big Wood water tanks, located east of State Highway 75, just north of town, have been under construction since early June.

Anyone driving north has undoubtedly noticed the equipment on the hillside (no, it’s not a monstrous new home that violates the hillside ordinance), as well as the construction on the side of the roadway for the 5,800 feet of piping necessary to connect the tanks to the city of Ketchum.

According to water superintendent Steve Hansen, this is the largest water project the city has undertaken since it got into the water business in 1978. Hansen said the new tanks will increase the city’s water reserves and improve water pressure.

The tanks should be operating by Dec. 1. Designed by J.U.B. Engineers, they will be 30 feet high and 70 feet in diameter. But like the one-million-gallon tank on Warm Springs Road, they will be back filled and landscaped, ultimately almost undetectable to the passerby.

The effects of the new tanks, however, should be clearly noticeable to Ketchum residents.

Hansen said that in addition to the water stored in the existing one-million-gallon tank in Warm Springs, the city needs 1.3 million gallons of water for domestic and irrigation uses. The two million gallons of the Big Wood tanks will provide that, plus an additional 700,000 gallons. That should serve the city’s needs for the next 10 years, Hansen said.

In order to get enough pressure to service the whole city, the tanks needed to be built at an elevation of 6,055 feet. (Ketchum’s downtown elevation is about 5,800 feet.) This increase in overall pressure will benefit areas such as Warm Springs, which sometimes does not have adequate pressure during peak periods.

Engineers found the current site, on Bureau of Land Management property, to be the most feasible location at the required elevation. The city secured a 30-year lease from the BLM for $2,200 per year.

The cost of the project is $3.4 million, which was funded by the sale of bonds. The construction cost for the tanks is $1.66 million, and the price of the pipeline connecting it to the city is $406,000.

Also included is an $86,000 contract for a new supervised control and data acquisition system. Known as SCADA, this state-of-the-art, computerized control device will monitor the pumps and equipment for the whole Ketchum water system.

If water in the Big Wood tanks gets below a certain level, for example, SCADA will automatically alert the Big Wood well, which feeds the new reservoirs, to send more water up the pipeline and into the tanks.

One water operator will be on-call 24 hours a day with a cell phone and laptop that hooks up to the SCADA system to monitor potential problems.

Hansen said this new system, used in many big cities, will be an enormous asset to the water department.

"The SCADA system and reservoir will give the water operator a better handle on what is being pumped to the customer," he said.