Perhaps the state could get their attention by apprehending a flagrant violator and imposing a fine for each sign posted, as the law allows. The ultimate solution is to take down the signs. It is legal to pick up litter, as community groups and individuals do. Signs in the state right of way are illegal, and it is legal to take them down. DelDOT has started doing that.
Residents can help too.
Donald B. Lake, of Wilmington, is on the New Castle County Council Road Sign Task Force.