Mill Branch is a long 1st order tributary to Tussocky Branch in Sussex County, Delaware.
Mill Branch rises in Ralphs, Delaware and then flows northerly into Tussocky Branch about 0.5 miles north of Ralphs, Delaware.
Mill Branch drains of area, receives about 44.6 in/year of precipitation, has a topographic wetness index of 816.27 and is about 20% forested.