Silverwood seeks sewage treatment plant

Before Silverwood Theme Park can expand and perhaps build a hotel, it needs a sewage treatment facility.

The popular rollercoaster and water park near Athol along U.S. Highway 95 is asking the Kootenai County Commission for a conditional-use permit to build the treatment facility on 96 acres next door.

A county hearing examiner will hold a public hearing on the proposal June 21.

The park, 20 years old this summer, uses large septic tanks with drainfields located throughout the 380-acre facility.

The Idaho Department of Environmental Quality has said the current system is no longer acceptable even though there is “no direct evidence” of effluent contaminating local groundwater. Yet the agency said that the system will “eventually create a public health or water quality problem,” wrote DEQ’s Gary Gaffney in an April 26 letter to the county.

“It’s time,” said Rand Wichman, a private planning consultant hired by the theme park. “If Silverwood hopes to continue to operate and continue to expand, and they expand a little bit every year, then they need to do this.”

Yet some people, including Post Falls Mayor Clay Larkin, aren’t too comfortable with the idea, especially until a master sewer plan for the Rathdrum Prairie is complete.

The leeriness comes just weeks after the county commission approved a conditional-use permit for Real Life Ministries to build an expansive new campus on the Rathdrum Prairie east of state Highway 41.

In 2005, the county signed an agreement with Post Falls, Rathdrum and Hayden not to approve large projects until the $300,000 sewer study is complete.

The cities allege that the county is now in violation of that agreement with the recent Real Life Ministries decision.

The study will dictate the size of sewer pipes, their location on the prairie and the placement of lift stations and treatment plants. The idea is to eventually eliminate septic tanks above the Spokane Valley/Rathdrum Prairie Aquifer, the source of drinking water for more than 500,000 people.

“With Real Life and now Silverwood, what is the overall goal for Kootenai County and wastewater treatment?” Larkin said. “At this point (the county) doesn’t even have a wastewater plan. All we are saying is hold off the conditional-use permits until the study comes back.”

Wichman, the former county planning director who helped cobble together the master sewer plan agreement, disagrees. He said the sewer study has no bearing on the Silverwood proposal because it is about six miles north of the study boundary.

Although not within the study area, the theme park is on the edge of an aquifer recharge area.

Wichman said no municipal treatment plant will ever locate near Silverwood, and that’s why the theme park needs to build its own facility.

He said Larkin should be happy that Silverwood is trying to do away with septic tanks, which is the ultimate goal and the best way to protect the environment.

“This is doing exactly what they want – eliminating drainfields,” Wichman said.

Silverwood, open May to September, generates about 4.6 million gallons of effluent a year. The proposed treatment facility would use the treated wastewater to irrigate trees and shrubs that the park would grow to use in its landscaping. The treated wastewater also would irrigate landscaping around the Boulder Beach Water Park.

Because the park is only open in the spring and summer, there is no need to store the treated wastewater in lagoons during the winter.

Larkin, who recently met with Silverwood’s wastewater consultant, is worried that a sewage plan could open the door for large housing developments, such as the denied Rickel Ranch project across from Silverwood.

Wichman said Silverwood doesn’t intend to allow any other development to use the treatment plant.