Wahpeton Water Tower

Wahpeton, IA | Water

ISG designed a new water tower to increase the City of Wahpeton's (the City’s) water supply capacity during peak summer months, while simultaneously meeting chlorine contact time (CT). Mixing and recirculation was also evaluated and designed to control the formation of disinfection by-products (DBPs) within the increased volume of the new water tower.

Located on the popular West Lake Okoboji, the City struggled to provide consistent water service to its community during the summer months, due in large part to their water tower’s limited holding capacity of 50,000 gallons. Rather than continuing to supplement water use from a nearby community, the City decided to increase its water storage capacity, capitalizing on its proximity to Iowa’s second largest fresh water source and its own treatment plant.

To meet the City’s year-round water supply demands, ISG was charged with designing and overseeing the construction of a new 200,000-gallon water tower to replace the existing 50,000-gallon tower. Planning and design for a water tower with inconsistent water demand posed some challenges, as water with older water age has the potential for DBPs to form and compromise water quality. Applying innovative solutions, ISG’s water solutions experts integrated a Tideflex mixing system into the final design that utilized a recirculation pump to create active mixing and accounted for swings in water storage needs and usage throughout the year. To ensure the City satisfied the strict CT requirements that were needed due to utilizing a surface water treatment system from West Lake Okoboji, the plant was reclassified from a direct to a conventional filtration facility.