Donohue’s Allen Williams will be presenting “Rising Lake Michigan Water Level Leads to 70 mgd Emergency Pump Station” at the Collection Systems 2021 Virtual Conference (March 23-25) held by the Water Environment Federation (WEF) in cooperation with the Michigan Water Environment Association. Allen’s presentation discusses Kenosha Water Utility’s (KWU) urgent response to rising Lake Michigan water levels by protecting the property and citizens with a permanent, risk adverse 72-million-gallon-per-day (mgd)) system, operational 7 months after initial concept.
Lake Michigan’s water level at Kenosha has risen to near record water levels, from 576 feet in 2013 to 583 feet in 2020. This rising water level threatened the wet weather capacity of KWU’s Water Reclamation Facility (WRF) and collection system that serves over 100,000 customers. The collection system includes two wet weather control elements for use when the WRF is at peak flow capacity: an equalization basin and 3rd Avenue overflow. Long-term planning for WRF and collection system capacity improvements were underway when an unprecedented rising water level rendered the 3rd Avenue overflow unusable in 2019.
Emergency pumping options were explored. Two axial flow pumps able to achieve 70 mgd were selected because they provided more flow, could be placed in the existing storm water outfall, and were lower cost than other alternatives. Because of the configuration of the outfall, one axial flow pump was located in the 99-inch storm sewer and one was located in the outfall structure. Pump station construction began in September 2019 and was completed in December 2019.
In May 17, 2020, the emergency pumps received their first real test as Kenosha received 3-1/2 inches of rain just days after previous rainfall events. The collection system flow was estimated at 200 mgd. The two emergency pumps at 3rd Avenue were operating during the event and the entire system was able to handle the high flows and avoid widespread basement flooding. The submersible, hydraulically driven pumps in an existing structure provided a unique solution to an emergency situation caused by rising water levels.
KWU continues to pursue wet weather management work to maintain or increase the collection system and WRF capacity. Ongoing work includes chlorine contact tank hydraulic modifications, WRF outfall modifications, and disinfection system expansion.
Allen is a water/wastewater engineer with Donohue & Associates in Milwaukee, Wisconsin. He is a licensed professional engineer in Wisconsin and Michigan who provides project management, planning, design, and engineering services during construction for wastewater treatment facilities and lift stations. Allen received a bachelor’s degree in biological/environmental engineering from the University of Missouri and a master’s degree in civil/environmental engineering from Marquette University. He has been working with KWU since 2014.