Marinas in Essington PA, a two mile waterfront with at least 8 marinas, down river from Philadelphia, with about 17 ft depth at low tide.
The Lagoon (thelagoon.net) $50/foot for the season aslo has a nightclub, hotel and resturant.
Rosse Marina in Essington also does repair work.
Anchorage Marina about $40/foot for the season, less for winter has the only fuel dock on the PA DE side of the river between the C&D and Philadelphia.
About 3 hrs at 5 knots to Center City Philadelphia.
Above Philadelphia; Neshaminy State Park Marina on the PA side and Winters Marina at Riverside NJ (winterssailing.com).
Neshaminy has probably the best winter storage with security provided by Park Rangers, State Police and Township Police patrols, but 3 to 4 hrs depending in the tide from center city, and a full days sail before you get to the bay.
On the Delaware Bay more marinas on the NJ side than DE side, and more "natural" than near Philadelphia, with protected wetlands, but Lewis DE is probably the prettiest destination.