The Marshalltown Water Works owns and operates the water distribution system serving Marshalltown and a large portion of the Central Iowa Water Association (CIWA). In Marshalltown, the system is divided into two elevation zones: high-elevation and low-elevation. The high-elevation zone was the focus of this project and is served by a booster pumping station.

Storage for the area was provided by a single 300,000-gallon elevated tower. The average daily demand (ADD) in the high-elevation zone is approximately 800,000 gallons per day (GPD). The Iowa Department of Natural Resources (IDNR) recommends that water utilities provide the ADD in “firm storage capacity.”

Demand in the high-elevation zone is developing steadily and CIWA has expressed interest in withdrawing additional water from the Water Works at the high-elevation zone connection. These demands increased the need for more firm storage capacity in the high-elevation zone.

We performed extensive modeling of the Water Works’ distribution system to evaluate the effects a new tower would have on the existing tower. To optimize storage in both towers, we recommended installation of a new 500,000-gallon water tower along with several other improvements to the distribution system.

A facility plan was completed outlining water modeling results and recommended improvements. The Water Works decided to proceed with the water tower project, and we designed and administered the construction for the 500,000-gallon tower.

Construction of the new water tower in a high-elevation zone created a storage quantity in line with IDNR Standards. The additional tower improves fire-fighting capabilities during emergency fire situations and serves as a welcome landmark to travelers on Highway 30.