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Microfiltration on the Missouri
Lower Brule Tribe Builds New Water Plant

Story by Mark Kemp-Rye, On Tap Editor
Photos by Rod Coker, Retired Tribal Utility Consultant, Indian Health Service

Did you know that each popcorn kernel contains a drop of water and that the corn won’t “pop” without it? Did you know that although popcorn probably originated in Mexico, it was also grown in China, Sumatra, and India years before Columbus visited America? Did you know that 1,000-year-old popcorn found in Peruvian tombs was so well preserved that it would still pop?

About the Photo: Lower Brule is one one of the first Indian reservations in the U.S. to use microfiltration (right) as a community water system treatment technology.

While popcorn might not be something you ponder very often, it was a consideration for South Dakota’s Lower Brule Sioux Tribe—one of the nation’s leading producers—when it came time to design a new water system. When it’s completed, Lower Brule’s new system will have plenty of water for irrigating the popcorn fields, and it will have good, clean drinking water for 5,000 people from a state-of-the-art microfiltration plant.

The Old Days
Water hasn’t always been readily available on the Lower Brule Reservation. Shirley Flute, long-time resident and advisor to the community leadership, recalls what it was like 40 to 50 years ago. “People got water from the river then,” she says.

“There was no treated water in those days, just river water that they had skimmed off what was floating on top and used that. If you wanted water delivered to your house it would cost $1 a barrel and $6 for a load of wood. Somebody within the community who had the means to deliver, would. Everyone knew how to conserve water because you had to make your supply last as long as you could.”

To illustrate how important conservation was, Flute tells a story of a visit her uncle made to her family back then. During the uncle’s visit, one of Flute’s children was hurt, and she and her husband had to take the child to the doctor. While they were away, the water barrel was delivered.

About the Photo: With a new microfiltration plant and an important role in one of the largest regional water projects ever devised, the Lower Brule Indian Tribe (right) has become a showcase for small communities.

“When we got home, we found him mopping the floor because the barrel had a leak in it and he didn’t want to waste the water,” she says. “I don’t know why he didn’t just pour the water into the other barrel, which was empty.”

For most of its history, Lower Brule was located right by the Missouri River where Flute and others got their water. Beginning in the 1950s, the U.S. Army Corps of Engineers began construction on the Big Bend and Fort Randall Dams. These projects meant that Lower Brule had to move to higher ground during the early 1960s. In 1963, the Corps starting flooding the area that created Lake Sharpe behind the Big Bend Dam.

With the move, Lower Brule got its first treated water—a small, package treatment plant with a conventional treatment process. By the 1970s, increased demand resulted in the original plant being replaced with two, six-foot-diameter pressure filters, each with a design capacity of 75 gallons per minute. Two additional filters were added in the 1980s during a renovation project.

Growth Means Change
By the mid-1990s, though, the pressure filtration system was struggling to meet U.S. Environmental Protection Agency (EPA) regulation limits during high turbidity events on the Missouri River. “Continued population growth of Lower Brule resulted in a need for additional capacity from the water treatment plant,” says Rod Coker, retired tribal utility consultant, Indian Health Service. “It was at this point that the Tribal Council (the governing body for the reservation) made the decision that the existing water treatment plant would not meet the needs of the community. They felt that their best long-term option was to abandon the existing facility and to construct a new water treatment plant. The council also decided to obtain the services of their own engineering firm so as to no longer be solely dependent on the technical resources of the federal government (Indian Health Service).”

The tribe’s engineering firm completed a microfiltration pilot study in October 1995. This was the first evaluation ever performed on the upper Missouri River for treatment by microfiltration. The study concluded that this treatment method would meet or exceed all current and foreseeable Safe Drinking Water Act regulations.

Funds for the project, however, proved difficult to find. Fortunately, the Tribal Council was able to become part of a large regional water project planned in South Dakota: the Mni Wiconi Rural Water Project.

That’s One Big Water Project
According to Jim McCauley, director of the Lower Brule Rural Water System, the Mni Wiconi Rural Water Project is the largest rural water project ever undertaken by the Bureau of Reclamation. “When it’s completed, this project will encompass four independent rural water systems, serve 55,000 people over 12,500 square miles, and deliver good, healthy drinking water to several counties in western and central South Dakota,” he says.

One Big Water Project

The Mni Wiconi regional water project was once billed “the largest engineering effort in the United States.” Consider these statistics:
• The project, when completed, will cover approximately 12,500 square miles.
• It will serve more than 55,000 people.
• It will encompass four independent rural water districts.
• The project cost will top $300 million.

“The Mni Wiconi project is a critically important drinking water project for the western half of South Dakota,” says Senator Tim Johnson, “[and will] bring a clean and dependable source of life’s basic necessity—water—to much of western South Dakota.”

“The Lower Brule Rural Water System will serve most of Lyman County off of its coreline system and will supply water to four communities and their distribution systems, which are located off the Lower Brule Sioux Reservation,” he says. “The total population served by the Lower Brule Rural Water System will be about 5,000 people.”

With the backing of the Mni Wiconi project and the support of several federal agencies, the Lower Brule Tribe was able to develop a coalition of funding support that would enable the construction of the microfiltration water treatment plant and link this system into the overall Mni Wiconi rural water system. The multi agency funding for this project was as follows:
• Indian Health Service - $257,000
• Housing and Urban Development - $311,000
• Environmental Protection Agency - $562,000
• Bureau of Reclamation - $235,000
• USDA Rural Development (Grant) - $150,950
• USDA Rural Development (Loan) - $145,238
• Lower Brule Tribe - $145,000

“Working with all these federal agencies was a major coordination effort on the part of the Lower Brule Tribal Council,” says Coker. “As a result, the tribe was able to construct (in 1999) one of the first microfiltration water treatment systems along the Missouri River. They are also one of the first Indian reservations in the U.S. to use microfiltration as a community water system treatment technology.

“Their operators have become extremely proficient in this treatment process,” he continues. “Their water treatment plant is considered a model facility, and they routinely entertain visitors.”

The people working in the plant are justifiably proud of their expertise. “Our treated water quality is consistently below 0.1 NTU [nephlometric turbidity units] no matter what kind of turbidity spikes we experience coming from the Missouri River,” reports Steve Langdeau, Lower Brule’s water treatment plant supervisor. “This is a welcome improvement to the water quality for local communities.”

Water Key to Economic Development
The economy of Lower Brule Tribe is based mainly on agriculture and tourism.
The tribe operates two farms totaling 6,000 acres, much of which is used for raising cattle and the aforementioned popcorn. Other activities include guided hunting, fishing on Lake Sharpe, and the Golden Buffalo Casino and Resort. Water will play an important role in current and future economic endeavors, say local leaders

Tribes Are Sovereign

Although the Lower Brule Sioux Tribe is found in South Dakota, it would be inaccurate to call it part of that state. Indian tribes are sovereign nations and are treated by the U.S. government as separate nations, responsible for self-government and with jurisdiction over their people and land. Treaties signed by the Tribes of the Great Sioux Nation and the U.S. between the 1820s and 1880s recognize this sovereignty and established boundaries still in effect today.

“In addition to improving the health of residents in the region, I strongly believe that the Mni Wiconi water delivery project will stabilize the rural economy,” says South Dakota Senator Tim Johnson. “Water is a basic commodity and is essential if we are to ever foster new rural development. Water development and economic development are especially important in helping the residents of the Indian Reserv-ations break the cycle of poverty. Several of the counties in this part of South Dakota are among the poorest in the nation. This project has and will continue to provide much needed jobs for this region.”

McCauley agrees that safe drinking water is the key to Lower Brule’s future. “The population increase at Lower Brule is a result of good, healthy drinking water dating back to the mid-1960s,” he says. “With the distribution system now being built as part of the Mni Wiconi Rural Water Project, the people of Lower Brule
will be able to receive good, healthy drinking water throughout the whole reservation. And with good drinking water, Lower Brule will continue to see the population increase due to healthy babies being born and people moving back to the Lower Brule Sioux Reservation to live on their own land.”

For more information about the Lower Brule Sioux Tribe, read a community profile on the Internet at To learn more about the Great Sioux Nation, go to You may also write to the Lower Brule Sioux Tribe at P.O. Box 187, Lower Brule, SD 57584-0187 or call (605) 473-5561.

The author wishes to thank Rod Coker, retired tribal utility consultant, Indian Health Service, for his invaluable help on this article.