4 big water projects underway in South Dakota

In a wooded site along the west shore of the Missouri River, an engineering marvel was taking shape one afternoon in March that will eventually help provide fresh water to hundreds of thousands of people.

Contractors hired by the Lewis & Clark Regional Water System had positioned 16-foot concrete rings above a structure known as a Ranney well that will draw water from an aquifer 140 feet below the surface. To form the sides of the giant well, workers jam several of the sleeves into the caisson structure that collects water through a series of pipes that extend outward at the bottom.

The new well is part of a $150 million expansion of the Lewis & Clark system that provides 44 million gallons of treated Missouri River water each day to 350,000 people in 20 communities in eastern South Dakota and parts of Iowa and Minnesota.

The construction is part of a wide-scale increase in water service capacity now underway in South Dakota, where water managers of several systems are implementing plans to serve the state for the next 40 to 50 years.

To ensure that steady supply of high-quality drinking water, four major projects are in progress to take more water from the Missouri River.

Two projects will expand existing systems, and two new systems are also in the very early stages of planning. In total, the projects could cost tens of billions of dollars and ultimately serve more than 750,000 people in South Dakota and two neighboring states.

Here is a snapshot look at the four water systems that hope to keep water flowing for the next generations of South Dakota residents.

Lewis & Clark Regional Water System

Headquartered in Tea, this system was authorized by Congress in 2000 and began delivering water in 2012.

The so-called base system is nearly completed at a cost of $711 million to provide 44 million gallons of treated Missouri River water per day to 20 communities in southeastern South Dakota, including Sioux Falls, and in Iowa and Minnesota.

The system uses wells positioned on the banks of the Missouri River to capture aquifer water that is treated and then shipped through a 54-inch main underground pipeline that diverts into smaller lines serving individual communities.

Two more expansions of the system are planned, with the first one now underway.

The first expansion began in 2022 and will cost an estimated $150 million to increase the water flow to 60 million gallons per day (GPD) by 2030. The project includes an expansion of the water treatment plant, addition of a new storage facility and construction of a new water collection well along the Missouri River near Vermillion.

The second expansion, now in the feasibility study stage, could increase water flow to 165 million GPD to accommodate population and industrial growth in southeastern South Dakota, eastern Minnesota and northwestern Iowa.

WEB Water system

The Water Investment in Northern South Dakota (WINS) project is a regional collaborative that includes the WEB Water system, the BDM Rural Water System and the city of Aberdeen.

WEB, the main portion of the project, was launched in 1975 to tap the Missouri River to initially serve the counties of Walworth, Edmunds and Brown in north-central South Dakota.

Since 1986, the system has taken Missouri River surface water at a point on Lake Oahe south of Mobridge, treated it to drinkable status and then shipped it through 688 miles of underground pipe heading east and north.

The system now provides up to 11 millions of gallons of water per day to 18 counties, 15 of them in South Dakota and three in North Dakota.

WEB has spent $20 million on improvements since 2016 to strengthen delivery systems, even though those projects have not expanded capacity to allow for more users.

To accommodate expected growth and increase area water needs, WEB is in the midst of an $82 million upgrade that will include 14 miles of 49.5-inch parallel pipeline and an expansion of its treatment plant from a capacity of 11 million GPD to 17 million GPD.

Western Dakota Regional Water System

This system was formed in September 2021 largely to pursue the data, political support and funding to build a 72-inch pipeline about 161 miles from the Missouri River to the Black Hills region.

The system is steadily gaining support from the state and federal governments, and is pursuing a $13 million feasibility study that is a requirement of a large project under the U.S. Bureau of Reclamation.

So far, 56 municipalities or water systems from Winner to Fort Pierre to Rapid City have signed on as partners in the project and could receive water from the project once operational, said Kristen Conzet, executive director of the system.

The pipeline would supplement the many existing West River water systems that draw from aquifers, which are slowly depleting, Conzet said.

“It’s needed for economic development, for agriculture, for tourism, for tribal nations and for national security resiliency,” Conzet told News Watch.

She testified before Congress on April 16 in support of a bill to authorize a formal feasibility study, noting that current water systems are not capable of providing the water needed to sustain growth in the region.

Both Conzet and U.S. Rep. Dusty Johnson of South Dakota told House members that water system expansion is needed to support regional growth, including at Ellsworth Air Force Base in Box Elder, which will soon be home to the new B-21 bomber program.

“Western South Dakota faces a clear and growing water challenge,” Johnson said. “This is not just a local priority; it’s a national security imperative.”

Dakota Mainstem Regional Water System

This massive proposed system is also in the planning stages and would provide water to a huge swath of eastern South Dakota and parts of Minnesota and Iowa.

The impetus for the system came when water managers examined the current and future needs for water in South Dakota and neighboring states and balanced that against the current and estimated future capacity of existing systems, said Kurt Pfiefle, director of the system that launched in 2023.

“We looked at what we have and said, ‘That’s all great, but are we done?’” he said. “Looking at the data, it became evident to us pretty quickly that we’re not done.”

So far, 57 potential members have signed on to the plan to build a pipeline up to 96 inches in diameter to carry treated water taken from Missouri River aquifers near Yankton. The project could take more than 20 years to build and cost as much as $10 billion, Pfeifle said.

Dakota Mainstem officials will attend their own feasibility authorization hearing before Congress, he said.

“It’s a massive footprint that we’re looking at,” Pfeifle said. “If South Dakota is going to continue to grow and we’re going to see more economic development opportunities, we need to have more water.”

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This story was originally published by South Dakota News Watch and distributed through a partnership with The Associated Press.