Bush River is a tidal estuary in Harford County, Maryland, located about 15 mi (24 km) northeast of Baltimore. The estuary extends from the community of Riverside, south for about 9 mi (14 km), to the Chesapeake Bay. The watershed area of tidal Bush River is 125 mi2 (320 km2), and includes Aberdeen Proving Ground, a military facility.
Bush River has three principal tributaries: Bush Creek, Church Creek and Otter Point Creek. The smaller tributaries are:
Coordinates: 39°22′30″N 76°15′56″W / 39.37500°N 76.26556°W