Bridge Drilling Moves Forward with Filtration System

Bridge foundation drilling project chooses Rain for Rent engineered slurry and sediment filtration system


Construction worth more than half a billion dollars needed to meet stringent water discharge regulations for a new bridge connecting Minnesota and Wisconsin. Water contamination from drilling bridge pier foundations needed to be treated and filtered to meet 25 NTU discharge requirements or the project risked losing $198,000 per day in labor costs. The water treatment system had to filter sediment, drill slurry and concrete from drilling into bedrock.

Due to the project’s high media profile and the river being a national scenic waterway, meeting and exceeding environmental regulations when discharging the water was vital.

Rain for Rent’s filtration system combined with HaloSource’s chitosan flocculant helped the project stay on track and allowed work to be completed before the winter freeze.

“Performance expectations and standards were extremely high. Rain for Rent was able to meet and exceed the expectations specified on the project.”


The contractor chose Rain for Rent because of the flexibility that their filtration system offered to treat 9.5 million gallons of water. Rain for Rent assisted in the design of the system to treat an array of incoming construction water that included suspended solids and high pH. As part of the environmentally friendly solution, HaloSource recommended their chitosan polymer to effectively knock out the solids before filtration and discharge into the river.


“The system’s performance to treat water will be a proven solution for future stormwater treatment in this area. It was effective at meeting strict water quality requirements and able to treat multiple incoming water conditions with excellent results,” according to Jennifer Hildebrand, Environmental Compliance Consultant with WSB and Associates.

You can read more about this project in the Water and Wastes Digest article: Protecting a Precious River.

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