Man-made alterations to Dutch Hollow Creek in Ellery over the years included straightening and widening the creek.
Those changes left it prone to erosion and a conduit for phosphorus into an already nutrient-rich Chautauqua Lake.
This week, the state Department of Environmental Conservation tentatively approved a pair of restoration projects on Dutch Hollow Creek and West Dutch Hollow Creek designed to control the grade of the creeks and stabilize their banks.
Plans call for adding rocks and native plants along nearly 2,000 feet of the creeks' banks and regrading their channels.
The work is part of a $1.1 million water quality grant from the DEC to Chautauqua County to help control erosion to streams flowing into Chautauqua Lake.