Lime Softening System Upgrade for Iowa National Guard Base

Camp Dodge Strives for Water Independence to Meet Future Demand

Located west of Northwest Beaver Drive in Johnston, Camp Dodge has been cemented as a community staple for over a century. This military installation where thousands of World War I soldiers once trained now serves as the headquarters for the Iowa National Guard, Iowa’s Fire Service Training Bureau, the State Police Academy, and numerous other organizations. As the facility has grown over the years, it’s been plagued by well-documented water treatment issues and inefficiencies. Based on their desire to own and operate an independent, modern water source with treatment, water storage, and an onsite distribution system, Iowa National Guard leaders reached out to the duo of Shuck-Britson and Snyder & Associates to design safe and efficient structural and water system upgrades.

Comprehensive Water System Plan Presents Viable Solutions

The Snyder & Associates team completed a comprehensive water system master plan to help determine the best course of action moving forward. Our planning efforts included the presentation of options for improved water quality with increased capacity and flexibility to meet future demands and regulations. Ultimately, the proposed improvements would allow the Iowa National Guard to serve adequate, reliable, and high-quality water to all camp residents and organizations on the base. After an extensive review of existing facilities, it was found that raw source water from two shallow groundwater wells contained high levels of iron and total organic carbon (TOC), along with small amounts of radium. The team analyzed two treatment alternatives — a lime softening system and an ion exchange process that was similar to the existing plant. Detailed equipment sizing plans, functional plan view layouts and elevations, and construction cost estimates for both alternatives were completed. Likewise, operational cost estimates for each alternative were provided to aid in determining which alternative would be more economical long-term.

Selected Lime Softening Water Treatment System & Additional Upgrades

After careful consideration and discussion, the Iowa National Guard committee authorized the Snyder & Associates team to proceed with the development of the lime softening water treatment system. This system was viewed as the most versatile treatment option, as well as the best alternative to meet the master plan directives. The lime softening process is able to reduce and/or remove hardness, iron and manganese, arsenic, total organic carbon (TOC), and radium from the source water. To provide system redundancy and allow additional capacity for the future, the final designs included two lime softeners for the facility. Additionally, a bulk steel silo for lime storage was included next to the facility. This 20-ton silo provides one-month storage for peak day demand and four-month storage at average day demand. To further support the new treatment system, an inspection of both source water wells was also recommended. Since these systems were built to handle capacities from nearly 60 years ago, it was determined neither well would be able to meet current-day peak demands. Our team recommended increasing the overall capacity by upgrading the existing submersible pump, motor, column, discharge piping, valves, and various electrical upgrades. This served as a near-term solution but was the most cost-effective since the expenses associated with a new supply and raw water transmission main were fiscally unachievable at the time. At Snyder & Associates, providing solutions that not only overcome immediate obstacles but also consider future expansion needs is at the core of our design process. To that end, much care was taken with the design of the facility's piping system. Our team made sure to create an easily accessible network to accommodate another lime softener in the future if conditions warrant. Our piping design can be quickly and easily extended for expansion.

Facility Upgrades Make Room for New Water Treatment Systems

Completed by our structural engineering team, the building addition for the lime softening equipment was added just to the south of the existing water plant facility. This building also houses the aeration process system, recarbonation, filtration, disinfection, chemical addition, and high service pumping equipment. Outside the building, lime sludge lagoons and a 150,000-gallon ground storage reservoir were constructed. In addition, the existing water plant facility was renovated by removing outdated process equipment. This provided space to convert the area into an office, conference room, laboratory, storage area, restroom with shower and lockers, and control room facilities. This ambitious project was completed in multiple phases implemented over several construction seasons to make them financially feasible for the Iowa National Guard. The updated lime softening water treatment facility has now been operational for a number of years and has continued to meet the needs of all camp residents and organizations on the base.