Bridgewater Township is a civil township of Washtenaw County in the U.S. state of Michigan. As of the 2000 census, the township had a total population of 1,646.
According to the United States Census Bureau, the township has a total area of 95.5 km2 (36.9 mi2). 94.7 km2 (36.6 mi2) of it is land and 0.7 km2 (0.3 mi2) of it is water. The total area is 0.76% water.
The River Raisin runs through the western part of the township, while the Saline River has its headwaters in Jaslin Lake in the northeast of the township.