Big Dry Creek is a tributary that joins the South Platte River near Fort Lupton, Colorado.

It rises in Jefferson County, Colorado at the mouth of Coal Creek Canyon at an elevation of 8,000 feet (2,400 m).

It receives treated wastewater from several municipalities, including the City and County of Broomfield, Westminster, Thornton and Northglenn.

The Big Dry Creek Watershed Association, a non-profit organization made up of individuals and representatives from local municipalities, monitors the creek's conditions.

The other Big Dry Creek rises in Douglas County and joins the South Platte River in Littleton.