Four regional water systems in South Dakota are advancing infrastructure projects that managers say will secure the state’s drinking water supply for the next four to five decades. Drawing heavily from the Missouri River, the four projects are currently underway or in early planning stages and span a footprint across eastern and western South Dakota, extending into parts of Iowa and Minnesota. The initiatives aim to relieve strain on existing networks, support rapid population growth, and provide long-term capacity for agricultural and industrial use.
Construction crews hired by the Tea, S.D.-based Lewis & Clark Regional Water System have begun installing a new water collection well near Vermillion to support a $150 million system expansion. Contractors positioned 16-foot concrete rings in March above a Ranney well structure, which will draw water from an aquifer 140 feet below the surface through a network of pipes extending outward at the bottom. The first expansion, which began in 2022, will also upgrade the system’s treatment plant and add a new storage facility. System officials expect the project to increase the network’s daily flow from its current 44 million gallons per day to 60 million gallons per day by 2030.
The Lewis & Clark system’s base network, authorized by Congress in 2000 and operational since 2012, cost $711 million to construct. It currently delivers treated Missouri River water to 350,000 people in 20 communities, including Sioux Falls, through a 54-inch underground main pipeline. Planners are already conducting feasibility studies for a second Lewis & Clark expansion that would raise daily output to 165 million gallons to accommodate future growth in the tri-state region.
In the northern part of the state, the WEB Water system is implementing an $82 million upgrade to expand its delivery capacity. Launched in 1975 to serve Walworth, Edmunds and Brown counties, the system currently provides up to 11 million gallons per day to 18 counties across South Dakota and North Dakota through 688 miles of pipe. The current project includes an expansion of the system’s treatment plant to a 17 million gallon daily capacity and the construction of 14 miles of 49.5-inch parallel pipeline.
To the west, the Western Dakota Regional Water System was formed in September 2021 to pursue a 72-inch pipeline running roughly 161 miles from the Missouri River to the Black Hills region. Kristen Conzet, executive director of the system, said the pipeline would supplement existing West River systems that rely on slowly depleting aquifers.
“It’s needed for economic development, for agriculture, for tourism, for tribal nations and for national security resiliency,” Conzet told News Watch. The system is currently seeking state and federal backing for a $13 million feasibility study required by the U.S. Bureau of Reclamation. Fifty-six municipalities and water systems from Winner to Fort Pierre to Rapid City have signed on as potential partners.
U.S. Rep. Dusty Johnson, R-S.D., joined Conzet in testifying before Congress on April 16 to advocate for formal feasibility study authorization. Johnson said current infrastructure cannot sustain planned regional growth, including upcoming expansions tied to the B-21 bomber program at Ellsworth Air Force Base.
“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.”
Further south, the Dakota Mainstem Regional Water System is mapping a massive pipeline project that officials say could eventually span up to 96 inches in diameter. Launched in 2023, the system would draw treated water from Missouri River aquifers near Yankton and distribute it to a broad swath of eastern South Dakota and portions of Minnesota and Iowa. Kurt Pfiefle, director of the system, said 57 potential members have signed on to the plan.
Pfiefle said the project could cost as much as $10 billion and take more than 20 years to complete.
“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.”
“It’s a massive footprint that we’re looking at,” Pfiefle 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.” Mainstem officials are scheduled to attend their own feasibility authorization hearing before Congress as they seek to secure the project.