The State Plumbing Commission
Plumbers and plumbing contractors in South Dakota are licensed by the State Plumbing Commission, which also sets the plumbing code that local inspectors enforce. Larger cities such as Sioux Falls and Rapid City run their own permit and inspection offices, while smaller towns may rely on the state for inspections.
East river and west river water
East of the Missouri, Sioux Falls, Brookings and Aberdeen draw from glacial aquifers, rivers and regional pipelines such as Lewis and Clark, and most of that water is hard enough that softeners are a household staple. West of the river, Rapid City blends Rapid Creek surface water with wells in the Madison and Minnelusa formations beneath the Black Hills. Across the state, snow-clogged sidewall vents and frozen garage lines are routine winter service calls. South Dakotans facing a cold tap can start with no hot water, and owners of on-demand units with tankless service.