Slow Sand System May Be Watershed For St. Maries Council Will Consider Ways To Meet Federal Standards

While St. Maries residents like the sparkling water that comes from Rochat Creek, they loathe the idea of doubling their water bills to make sure it meets federal health standards.

Last Tuesday, they voted 327 to 94 against paying for a $5.5 million mechanical filtration system that would remove any threat of disease.

But there may be a cheaper, lower-tech way to accomplish the same goal.

A slow sand filtration system is one of three other options that the City Council will consider for meeting the regulations, said council member George Currier.

It’s the only option that would allow continued use of surface water, rather than ground water.

“The technology has been around for centuries. It’s very appropriate for small systems,” said Steve Tanner of the Idaho Division of Environmental Quality.

His agency enforces the drinking water rules, which the city has agreed to meet.

The council held Tuesday’s advisory election after nearly 1,000 residents said in a survey that they wanted to keep getting water from Rochat Creek.

The sand filter approach intrigues Currier. But until now, he said, that wasn’t fully explored because the city wasn’t sure such a system would remove the tiniest disease-causing organisms.

But in August, an article in an Environmental Protection Agency publication declared that slow sand systems are effective against the parasites giardia and cryptosporidium.

That sets the stage for the new EPA rules that are being written, Tanner said.

Many Idaho communities use slow sand systems, including Colburn and Troy.

Rapid sand filtration systems such as one used by Sandpoint are even more common, Tanner said, but they are more costly because they require full-time operators and the use of chemicals.

“Slow sand is a biological treatment, where you run the water through a bed of sand 50 to 100 times slower than with a rapid sand filter,” he said.

A slow sand system can’t be put on a flood plain. It would take up 2 or 3 acres, Tanner said.

Currier estimates the cost of such a system at $3 million to $4 million, including a replacement of the 60-year-old pipeline that brings water from the creek.

The city’s two other options involve ground water.

St. Maries could put a well at the upper end of its aquifer, some five to seven miles up the St. Joe River near Rochat Creek. That system would cost around $3 million, Currier said.

Or the city could upgrade existing wells in the Riverdale area. At $1.7 million, that might be the cheapest option, Currier said. It also would require removal of manganese, a metal that exists there in high enough amounts to discolor and flavor the water.

The council is sure to discuss the water situation when it meets Monday, Currier said.

“We don’t want to bankrupt the community, but by the same token, it needs to be taken care of,” Currier said.

, DataTimes MEMO: This sidebar appeared with the story: THREE OPTIONS In order to make sure the St. Maries water system meets federal health standards, the City Council will consider: Installing a slow sand filtration system. Would allow continued use of surface water, and would cost $3 to $4 million. Putting a well at the upper end of the aquifer. Requires use of ground water, and would cost $3 million. Upgrading existing wells in the Riverdale area. Requires use of ground water, and would cost $1.7 million.