Water from the Missouri River flows into 20 cities and rural water systems in the eastern part of the state. There are now more projects in the works to supply Missouri River water to the rest of the state. It’s part of a long-term plan to begin tapping an irrigation source promised decades ago.
The state’s plan to develop water systems from the Missouri River began in the 1940s when the dam and reservoir system went up to prevent flooding.
A congressional plan called the Flood Control Act of 1944, also known as the Pick-Sloan Plan, engineered dams and reservoirs along the river. Those plans also included the promise of water to the state.
The state still has around 95% of its allocated water available, according to Troy Larson, executive director of theLewis and Clark Regional Water System.
“South Dakota was promised a lot of irrigation capacity. Irrigation has happened a little bit but not much, but the new reincarnation of irrigation became rural water. Right now we estimate that of all the water promised to South Dakota between irrigation and rural water we are only accessing about 5.5% of that water,” said Larson.
The Lewis and Clark Regional Water System is the leader in the state for pulling water from the Missouri River. The river feeds nearly two dozen cities and water systems.
When it’s completed, the system will produce 44 million gallons of water a day with future plans to increase capacity to 60 million gallons a day.
Larson said these projects should have been considered sooner but recent drought years have made them a priority.
There are three additional water projects in the works. One is called WINS – which stands for Water Investment in Northern South Dakota. Another called the Western Dakota Regional Water System serves west river cities, and Dakota Mainstem will bring more water to eastern communities.
All three projects are looking to pull water from the Missouri River and share it throughout the state. They’re all using the Lewis and Clark system as their model.
Dale Tech, public works director for Rapid City, said the project with the Western Dakota Regional Water project is in its beginning phase..
They're working with the School of Mines to investigate just how much water western counties will need. They hope to build a system designed to solve any future water shortages for a dryer climate.
“With that knowledge, once again, West Dakota Water Development District commissioned a study about what would the next steps be to investigate this further, or move towards a project," said Tech. "One of the recommendations of that study was to create an entity to be the lead on the efforts to investigate and potentially bring Missouri River Water to western South Dakota."
The northern part of the state intends to expand on a project already developed by WEB Water.
Aberdeen's Mayor Travis Schaunaman said the city’s population growth and a desire to offer higher quality water spurred the decision to expand their water source.
“The quality of water that comes from the Missouri River is far superior, so that is first and foremost issue. But secondarily we are kind of capped in our value-added ag industrial production here because most of that consumes a considerable about of water," said Schaunaman. "We’ve got two industrial consumers that each on a peak basis utilize about a million gallons per day, and that’s not something we can sustainably add to with our existing water source.”
The eastern part of the state is also planning for future increases in water demand and that has spurred development of the Dakota Mainstem project.
All water projects in the state work closely with the U.S. Geological Survey. Galen Hoogestraat, a hydrologist with the agency, said they provide analytical data to the water management companies.
Hoogestraat said water projects are getting attention because a lot of South Dakota cities don’t have a water source that can withstand drought cycles.
“Those that rely on shallow ground water wells or rivers that maybe have relatively small drainage areas, those water systems are more susceptible to drought impacts during dry climate cycles. So if you have a larger river system like the Missouri River, it is viewed as a more stable or resilient or more likely to mitigate those impacts that you would have during the drought cycle,” said Hoogestraat.
All of these water systems will come at a cost and receive financing from multiple sources.
The largest amount will come from federal government grant dollars, while the state and local city governments will have to come up with the rest.