1,500-foot seawall sought on North Shore

Several property owners along the North Shore of Flathead Lake are requesting permits to construct a seawall and walkway along the shore, stating in county permit applications that it is needed to prevent further erosion of their properties.

The Flathead County Planning Board will issue a recommendation on the permits during its May 11 meeting, after which the county commissioners will decide whether to approve or deny the lakeshore construction permits.

Four applications dated March 28 outline plans to build the 1,505-foot structure along the lakeshore north of Dockstader Island. It would be composed of vinyl sheeting, which the permit application states would have the appearance of textured concrete.

The 10-foot panels would be driven more than 6 feet into the lake bottom, with just over three feet extending above the gravel currently in place to mitigate erosion on the shoreline.

Included among the applicants is Jolene Dugan, one of the developers behind the unfinished bridge connecting Dockstader Island to the mainland. The other applicants include Avah Walker, Flathead Properties LLC and a pair of trust funds.

County planning director Mark Mussman said the project was originally proposed last December, but his department rejected the first round of applications in January after determining they did not provide enough information.

“There’s some marinas that may have seawalls, and throughout Flathead County certain lakes have riprap retaining walls, but I am not aware ... of a continuous seawall of this magnitude,” Mussman said.

He added that in 2013, the county approved a similar seawall project along the North Shore, totaling about 1,000 feet in length, but the project was shelved after the applicants were denied a third permit extension.

To win county approval under the Montana Lakeshore Protection Act, Mussman said the applicants must prove the structure will not diminish water quality or habitat for fish and wildlife, interfere with navigation or other recreation activities, create a public nuisance, create a “visual impact discordant with the natural scenic values” or alter the characteristics of the shoreline.

The applications state the seawall would cause no adverse environmental impacts, asserting it would not degrade water quality and could have a net positive effect by preventing nutrients and soils from eroding into the lake.

The Community Association for North Shore Conservation, a local nonprofit group that has vocally opposed the nearby bridge project, objected to that claim.

In comments submitted to the county April 19, organization co-chairman Dave Hadden wrote that the installation of the vinyl panels will disturb old logs underlying the beach, along with gravel and lake bed sediments. The letter also states the project fails to meet criteria related to visual impacts, legal road access and impacts on adjacent properties.

In addition to a lakeshore construction permit from the county, the project would also require approval from the U.S. Army Corps of Engineers and potentially require a flood development permit from the Montana Department of Natural Resources to proceed. Both agencies have submitted comments to the county planning department criticizing the proposal.

The applicants state the proposed seawall is necessary to combat erosion of the lakeshore resulting from the raising and lowering of lake levels since the construction of Kerr Dam in 1937. The application claims that since that time, the shoreline has eroded by 1,500 feet.

Marc Pitman, an engineer with the state Department of Natural Resources and Conservation, submitted a letter including photo surveys of the shoreline and argues that they conflict with the applicants’ claims of historical shoreline erosion.

“Contrary to the applicants’ assertion that the existing gravel measures have failed and the shoreline is continuing to erode, the photographic evidence appears to support that the measures in place since 2006 are indeed working,” the letter states, referring to gravel installed to mitigate erosion.

Pitman also wrote that the application is insufficient for obtaining a flood-plain development permit, since the structure’s design has not been certified by a professional engineer licensed in Montana, a requirement under state law.

Citing an analysis of groundwater flows along the lakeshore, the applications also conclude that water does not flow between the uplands and the lake, and that water moves vertically, not horizontally, in the soils impacted by the sheet piling.

In an April 13 letter to the county, the Army Corps of Engineers’ state program manager Todd Tillinger questioned the potential impacts to groundwater flows, saying that the structure would “interrupt and impair the flow and circulation of water in Flathead Lake and adjacent wetlands.”

Tillinger contended that the project would lead to changes in water quality and wetland hydrology, alter biological processes and potentially impact bull trout habitat, alter the shoreline of the U.S. Fish and Wildlife Service’s adjacent Flathead Waterfowl Production Area and alter the visual aesthetics of the shoreline.

The county planning board will review the proposed project at its May 11 meeting at 6 p.m. in the Earl Bennett Building’s second-floor conference room.

Reporter Sam Wilson can be reached at 758-4407 or by email at swilson@dailyinterlake.com.