Water System Expansion

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Water system expansion project
adds customers and improves system

Kingbrook Rural Water, Inc. Implements Long-Range Plan by
Improving System Performance and Serving New Customers

Project Owner:
Kingbrook Rural Water, Inc.

Key Experience:

  • Completion of a long-range plan spanning several decades and multiple projects to interconnect water sources
  • Optimized treatment plant performance by moving chemical injection points and adding finished water storage
  • Large rural water pipeline project that extends service to new members and improves system capacity

Key Features:

  • USDA Rural Development funding, including grant and low-interest loan, saving client over $4 million in interest payments
  • 215 miles of pipe 1½” to 16” in diameter extending service to 260 new customers
  • New 630,000-gallon bolted steel storage tank

Kingbrook Rural Water, Inc. is a regional water provider in eastern South Dakota, serving approximately 4,950 residential, livestock, and commercial users in more than 11 counties. They serve customers from three different water treatment plants located approximately 50 miles from each other. The treatment plants are located in rural areas near the small towns of Bruce, De Smet and Chester, SD. The original system construction happened in the late 70’s and early 80’s. All three treatment plants were expanded in the 90’s and early 2000’s to meet their growing needs.

In the mid-2000’s, DGR Engineering (DGR) and Kingbrook began developing a long-range plan to interconnect their three treatment plants with large diameter transmission mains. The goal of the plan was to provide another level of backup at each treatment plant in case of an emergency. This emergency planning was in addition to the typical approach for systems to have standby generation, backup pumps, etc. Another goal of the plan was to provide operational flexibility by having two sources that could serve any of their subsystems. Each year, an annual planning event is held to review system operations, new growth trends, and changes in existing customer demands. The plan is updated and modified to meet the current and future needs of the system.

Approximately every four to five years, these plans are combined into a project that not only improves the system for existing customers, but also extends rural water service to new customers. Conducting systematic expansion projects results in regular improvement of the system. It also allows the utility to make the most efficient investments in their system by taking advantage of low-interest loans, grants, and economies of scale when bidding out multiple improvements and new connections as one large project. In the past 15 years, Kingbrook has installed about 50 miles of transmission mains between their treatment plants, but still needed about 25 miles between Bruce and De Smet to complete the long-range planning goal of connecting their water treatment plants.


Kingbrook began planning their current expansion project in 2015. Tremendous demand for new service connections made this expansion project the largest expansion project ever undertaken by Kingbrook. Much of the additional water demand was located within the De Smet plant service area that couldn’t be met with the existing system’s transmission capacity. Previous projects had increased elevated storage capability in the De Smet plant service area and connected with the Chester plant. But more capacity was needed to serve the new customers.

Our Approach
DGR began by helping Kingbrook optimize the De Smet treatment plant. Highly variable iron concentrations from their north well field made chemical dosing problematic. Kingbrook optimized the treatment efficiency of the plant by changing oxidants and moving the chemical dosing locations. These changes extended the filter runtime, reduced the overall chemical requirements of the plant, and increased production capacity.

Next, the existing storage capacity at the De Smet treatment plant only had about three and a half hours of peak demand storage, which made plant operation difficult. Kingbrook selected a two-phase process to build one 630,000-gallon tank now, which will increase on-site storage to about eight hours, and build a second tank as part of a future project, when demand increases.

Finally, DGR designed pipeline that would serve the new customers and complete the interconnection to Kingbrook’s third water source near Bruce. When complete, this project will add approximately 190 miles of pipe for system improvements and new services, as well as approximately 25 miles of 12, 14, and
16-inch diameter pipeline to interconnect the Bruce plant with
the De Smet plant.

The project is was finished in the summer of 2019. This project
not only meets the needs of new customers who signed up on
this expansion project, but it also achieved a major milestone
of Kingbrook’s long-range planning – the interconnection of
their water sources to improve system reliability and flexibility
of operations.