Why not Nockamixon State Park? ... about 20 minutes from Lansdale? 10X the size of Lake Galena. .... and besides If I correctly remember, Lake Galena has a 'size limit' of 16-18ft. max.
Delaware River is a PITA because of the current flow and it 'narrowness' plus lack of 'services', Ditto lack of 'services' on Delaware Bay until you get near Cape May.
Other alternative is the Northern Chesapeake Bay .... about 1-3/4 hrs. from Lansdale. Ches. is THE PRIME sailing venue for the MidAtlantic area.