The owners of a small island off Duck Key have asked Monroe County to amend its land-use plan to create a new category county planners are calling "redredging."

The owners of Walker's Key will meet tonight in Marathon to tell the public about their plan to dredge a 30-foot-wide-by-700-foot-long privately owned channel and the new dredging category.

The county's comprehensive plan prohibits new dredging, only allowing maintenance dredging in areas without seagrass and hard-bottom habitats. for seagrass or hard-bottom habitats, maintenance dredging is only allowed in "public navigation channels," constructed or kept by a federal, state and local government agency.

Little Conch Key Development wants to dredge the channel to Walker's Island on the ocean side off Duck Key. The channel has seagrass beds, so the company proposed the new dredging category.

Altering the comp plan requires approval from the County Commission and the state Department of Economic Opportunity, which oversees development in the Keys.

The Planning Commission recommended approval of the new dredging category when it met in November. County planning staff also recommends approval.

The development company's biologist, Sandra Walters, says the project wouldn't open the Keys to widespread dredging on private lands because each property owner wanting to do so would have to submit their own plan that would also need county and state approval.

"This will further the principles of guiding development," Walters said. "[The comp plan] says to protect and restore, and this does both."

Such projects also must be approved by the Army Corps of Engineers and the state Department of Environmental Protection or the South Florida Water Management District.

"This is a long, arduous and expensive process," she said.

The Walker's Key channel was first dredged in the mid-1950s to about 5 to 6 feet, Walters said. The channel since accumulated extensive sediment, and currently the depth ranges from 0.47 feet to 2.86 feet, with an estimated average depth of about 1.5 feet, according to the county.

If approved, the county would allow the Little Conch Key Development Co. to dredge the channel no deeper than 4.5 feet, County Planner Mayte Santamaria said.

The Little Conch Key Development Co. also tentatively agreed to give to the state 26 acres of sensitive bay bottom and mangroves around the channel for a "conservation easement," Walters said.

The meeting is at 6 p.m. today at the Marathon Government Center.

tohara@keysnews.com