Howardwick is a city in Donley County, Texas, United States. Its population was 370 at the 2020 census. Howardwick is located north…Howardwick is a city in Donley County, Texas, United States. Its population was 370 at the 2020 census. Howardwick is located northwest of the center of Donley County. It is on the north side of Greenbelt Reservoir, an impoundment on the Salt Fork Red River. Texas State Highway 70 runs past the eastern side of the city, leading south 8 miles to Clarendon, the county seat, and north 11 miles to Interstate 40.