The Broadkill flows for its entire length in eastern Sussex County.

[4] From Milton, the Broadkill River flows generally eastwardly, passing through wetlands and salt marshes in the Prime Hook National Wildlife Refuge.

[5] After approaching to within one and a quarter miles (2.0 km) of Delaware Bay, the river parallels the shoreline a short distance inland for approximately two miles (3.2 km) before flowing into the bay in northwest of Lewes.

The United States Coast Guard maintains a station near the mouth of the Broadkill at Green Hill.

[8] As of 2005[update], an annual canoe and kayak race was being held on the river in Milton.