Bridgewater is a city in southeastern McCook County, South Dakota, United States.

[6] A post office called Nation was established in 1880, and the name was changed that same year to Bridgewater.

[7] According to the United States Census Bureau, the city has a total area of 1.13 square miles (2.93 km2), all land.

There were 254 housing units at an average density of 224.8 per square mile (86.8/km2).

33.3% of all households were made up of individuals, and 21.1% had someone living alone who was 65 years of age or older.

35.5% of all households were made up of individuals, and 25.3% had someone living alone who was 65 years of age or older.

Humid continental climate is a climatic region typified by large seasonal temperature differences, with warm to hot (and often humid) summers and cold (sometimes severely cold) winters.