The Point Reyes National Seashore announced it will start removing oyster racks and aquaculture debris from Drakes Estero, a year and a half after Drakes Bay Oyster Company ceased operations. The National Park Service and the National Park Foundation are devoting $4 million for the work on the marine wilderness, which is slated for completion by early 2017. The cleanup entails removing five miles of wooden oyster racks that weigh 477 tons with a mechanical excavator. About 1.5 acres of the estero floor will also be dredged in order to remove things like oyster bags, clam bags, loose Pacific oysters and plastic aquaculture gear; the dredging will free up room for eelgrass to grow, the park said. Debris will also be removed from sandbars where harbor seals haul out. Last year, when the park secured approval for the project from the California Coastal Commission, it said it considered using divers to handpick debris, but that much of it was too heavy and to do so would take a very long time. As part of the cleanup, the park will collaborate with the California Department of Fish and Wildlife and state universities in the long-term monitoring of eelgrass, water quality and non-native species like didemnum vexillium, an invasive tunicate in the estero that the park hopes will decline without the oyster racks’ hard substrate. Road and water access to the estero will be closed on weekdays during the project but open on weekends and holidays. Trail access around the estero will not be affected.