HAYDEN - The Hayden City Council on Tuesday passed an ordinance authorizing the issuance of revenue bonds to raise up to $18.5 million to make improvements at the wastewater treatment facility used by city businesses and residents.

"We have looked at all the other options," Hayden City Administrator Stefan Chatwin said Wednesday. "We are looking for the very best and cheapest money we can find."

The treatment facility, operated by the Hayden Area Regional Sewer Board, needs improvements to meet significantly higher permit standards in the near future for discharged water set by the U.S. Environmental Protection Agency.

Water treated at the plant, located at 1079 N. Atlas Road in Hayden, is discharged into the Spokane River for a portion of the year and applied to land at a tree farm and alfalfa field during growing season.

Ken Windram, administrator of the treatment facility, said sewage with between 6,000 to 8,000 parts per billion of targeted phosphorus enters the plant.

Meeting all current permit requirements, treated water is discharged with about 4,000 parts per billion of phosphorus.

The future permit standard will be 50 parts per billion of phosphorus.

"What we are being asked to do is at the limits of technology," Windram said.

The cleaner treated water will be reusable in more ways. Windram said the treated water will be going from what he called "Class C" now to what is considered "Class A" after the facility improvements.

All the construction has to be completed in nine years, and the facility must show it can meet the new, higher permit standards the following year.

The $18.5 million is the city of Hayden's portion of the project cost. Kootenai County and the Hayden Lake Recreational Water and Sewer District also are owners of the facility.

The improvements will total about $30 million. The total cost will be more defined once improvement designs are completed.

Chatwin said the city is seeking a 1st District Court judge's approval of the bond issuance. The city believes the project is "ordinary and necessary," meaning it's required to avoid costly fines for noncompliance.

Fines can total up to a $1 million a month for noncompliance with the EPA permit standards, Windram said.

The revenue bonds would be paid back through user fees, not through property taxes, Chatwin said.