Forcemain Replacement Project-St. Joseph, Michigan

Wightman is all about water, numbers, and engineering.

According to United States Geological Survey, Michigan encompasses a total area of 96,714 square miles, including 56,539 land area square miles and 40,175 water area square miles. This means 41.5% of Michigan is covered by water including all inland water, coastal water, and the Great Lakes. That's a lot of water!

Despite Michigan being surrounded by water, it falls to municipalities to protect the freshwater sources, provide clean water to residents, and protect the environment by creating and installing safe solutions for wastewater management.

Wightman was proud to partner with the Southwest Michigan Regional Sanitary Sewer and Water Authority (The Authority) to replace approximately 8,700 feet of 20-inch ductile iron forcemain with fusion welded high density polyethylene (HDPE) pipe. The underground piping system conveys approximately 2.3 million gallons per day at up to 5,500 gallons per minute from The Authority’s collection system to the St. Joseph/Benton Harbor Joint Wastewater Treatment Plant (WWTP) on Marina Island. The forcemain was originally installed in 1975 and had deteriorated over the decades it was in use. This deterioration could have had cataclysmic results - from forcemain breaks to wastewater leaking into nearby freshwater sites to those adverse effects impacting the nearby sensitive environment.

Wightman's Engineering team faced many challenges during this project. An above ground forcemain bypass was installed for a portion of the project with limited utility real estate to ensure customers would have uninterrupted service throughout the duration of the upgrade. Additionally, the replacement forcemain connections were completed at night, during off-peak flow periods, to alleviate service disruptions. Extra care was taken with the installation of the forcemain due to its close proximity to the St. Joseph River and adjacent wetlands, requiring temporary dewatering of ground water for portions of the pipeline construction and directional drilling a new forcemain crossing under the Morrison Channel of the St. Joseph River to Marina Island.

This critical infrastructure project was completed on time and under budget within a sensitive environment along the banks of the St. Joseph River. The new HDPE forcemain will ensure uninterrupted, reliable wastewater service for the member communities of The Authority now and for generations to come.