The draws of the Lord Delaware (S33) bridge, mile 0.8 at West Point, and the S629 bridge, mile 28.5 at Walkerton, shall open on signal if at least 24 hours notice is given. The drawtender service for either bridge shall be increased to the degree determined to be adequate within 30 days after written notice is received from the District Commander to do so.
33 C.F.R. §117.1015