Dam faces uncertain regulatory future

Aug. 7—Two regulatory agencies reviewing a plan to raise Meadow Park Dam about 18 feet returned with vastly different estimates for the required environmental mitigation.

Those early estimates left engineers eyeing a project that could cost between $50 million and $100 million to provide a larger water reservoir for the community.

"We were somewhat surprised to find that the two agencies had different requirements for mitigation," said Kevin Young, with J.R. Wauford and Co. "It is a significant difference."

Extensive inventories found 71.58 acres of wetlands and 18,520 feet of streams in the project area.

The U.S. Army Corps of Engineers has said it would require the city to mitigate 8,852 feet of streams and 29.73 acres of wetlands.

The Tennessee Department of Environment and Conservation has said it would require the city to mitigate the full amount of wetlands and streams impacted.

"We have been told by the Corps of Engineers that, if we just do the Corps part, this will be the largest mitigation project they have ever permitted in the Nashville district," Young said. "It is a big project."

Wetlands are to be mitigated with 2 acres of restored or repaired wetlands for every 1 acre of impact.

Mitigation can be done on property owned by the city or through mitigation banks or similar mitigation projects. Mitigation has become a specialty work area, Young said, and he recommended the city contract with a specialist that can guarantee delivery of mitigation credits in a form that the regulators will approve.

The city must have a mitigation plan approved by regulators before the permit would be issued.

Young said the Corps of Engineers was looking at mitigation for the area impacted from the elevation of the existing dam to the elevation of the new dam. TDEC is taking into account the area — 8-9 feet — to the spillway below the top of the dam.

"That's why there is a difference," Young said.

A meeting was requested with the TDEC commissioner to review the difference in federal and state mitigation requirements.

"Our attempt was very straightforward — to get TDEC to agree to only require the same mitigation that the federal agency was requiring," Young said. "We were disappointed in that meeting."

The commissioner did offer to have his staff consider ideas to reduce their mitigation requirements.

Wauford and the consultants hired for the inventory have been developing six ideas to be presented to TDEC for consideration.

The project to raise the dam is being considered to meet water storage needs for Cumberland County for the next 40-50 years.

Raising the dam by about 18 feet will inundate 360 acres.

Young said the project will allow the city to store more water from rain events, but also to take advantage of a water harvesting permit for Lake Tansi.

A project to pump water from Lake Tansi to Meadow Park Dam was completed in 2012 to help provide a water source while the city completed repairs to the dam.

The water harvesting permit allows the city to draw water from Lake Tansi, but Young noted the permit limits the time period water can be harvested during the year.

"That doesn't really benefit the city right now because the time of the year you're allowed to harvest that water, Meadow Park Lake is typically overflowing its spillway. If you pump that water over, there's no where to store it," Young said.

Young said the next steps for the city include expanding the contract with the consultant for those six ideas.

Wauford also needs to complete the environmental permit application, which includes an analysis of other alternatives and hiring a mitigation contractor.

The dam construction will be a big project. Young said it was not yet certain if the plan would be to raise the dam or to build an entirely new dam just in front of the existing one.

"It depends on what's under the dam," he said.

The city already owns about two-thirds of the property that would be inundated by the higher dam, but they need to survey property that will need to be purchased for the project.

And, because the lake will serve as a water supply source, trees must be cleared before it is inundated.

There are still a lot of questions to answer, Young said. He offered two estimates for the project, a "best case scenario" of $50 million if the state agrees to the lower mitigation requirements and good rock in the area of the dam for construction, and a "worst case" of $100 million that includes the full mitigation required by TDEC.

About half the cost of the project will be wetland and stream mitigation, he added.

The city has been exploring raising Meadow Park Dam and water supply options for many years. The city serves its water customers and the Catoosa Water Department customers from water from Meadow Park Lake and Holiday Lake.

The city also sells water to South Cumberland Utility District.

There could be some funding available for a water supply project, particularly one that would impact the entire community.

Greg Hanson, president of the newly formed Cumberland Plateau Water Authority, invited members of the council and the city's water department to attend a "water summit" to discuss the state of drinking water in the area. The regional water authority board is made up of individuals living in each of the county's water utility districts, with three representing the city of Crossville.

The authority began work in January and has been working on organizational matters like banking and mail delivery. Now, they're ready to start planning for the future and fulfill their mandate under the special act that created the board — to consider regional approaches to water supply for the future growth of the community.

"TDEC is one of the pushing forces behind the concept of a water authority and the concept of regionalization of water resources," Hanson said.

TDEC has funding available for water supply projects through its American Rescue Plan Act — up to $20 million for water project.

"I don't think we're in a position to apply for it this year. I certainly think we could apply next year. It would require that the water authority partner with one of the utility operations. In this case that would probably be the city of Crossville," Hanson said, referring to the dam project.

"This would be an opportunity to get $20 million of federal funds with only a 5% match required," he added.

The summit is set Aug. 24 at Cumberland Mountain State Park in the lower level of the park restaurant.

It will begin at 8 a.m. and is scheduled to go through the day. The public is invited to attend.

Heather Mullinix is editor of the Crossville Chronicle. She covers schools and education in Cumberland County. She may be reached at hmullinix@crossville-chronicle.com.