City tests new water treatment plant

SANDPOINT — After months of work, city staff are preparing to put the new water treatment plant through its paces before it goes into service.

Since construction started in March of last year, the plant is scheduled to undergo full testing in about six weeks that will likely conclude sometime in July. After that, the plant should be ready for service sometime this summer.

Even so, there’s still plenty of work to be done before the project is completed. Within the next few weeks, workers will install the membrane filtration system.

The water treatment plant will replace the old systems and facilities, which will first be shut down and then retrofitted to assist the plant complex in other ways. Remnants of the old plant will serve the new facility for ancillary purposes that increase efficiency.  

“For example, one of the buildings that holds the existing filters will now hold chemicals,” Public Works Director Kody Van Dyk said.

 If work continues to go smoothly, the plant should be completed within another half-year or so. Van Dyk estimates the project will be wrapped up by September or October.

The plant will dramatically increase the city’s capacity to treat water for public use. With both a mountain watershed and Lake Pend Oreille available, Sandpoint has no lack of access to fresh water.

Delivering it safely to the community is another matter. The old plant could handle three million gallons a day, which city staff determined to be insufficient for projected growth.

By contrast, the new facility will be able to handle more than 10 million gallons of water per day. It will also employ membrane filtration, a system that works by running water through a thin layer of material that separates substances when a driving force is applied. This system is able to filter out incredibly small substances from the city’s water.

In addition, the city is working on replacing water mains to facilitate the increased capacity. The water main beneath Sand Creek will be replaced by a new 24-inch model, as will the 12,000 feet of main that carries water to Ponderay and Kootenai. This will substantially expand the water boundaries, allowing Ponderay, for example, to bring water service to the recently-purchased Field of Dreams.

According to Van Dyk, the project has progressed smoothly so far, and the work quality is proving itself to be solid. The water treatment plant is based on a model by the Pall Corporation, which sent an inspector out to make sure everything was constructed according to specifications. Usually, these inspections take six weeks, but Van Dyk said he would likely be finished in three or four due to the superior build quality.

“Everything has gone well,” Van Dyk said. “We’re coming in right on budget.”