MDOT Innovative Technology Demonstration


In June 2019, JET Filter System partnered with the Michigan DOT and LS Engineering in a field demonstration program of maintainable weep hole filters. The units were installed in a box culvert under US-31 at the north branch of the Macatawa River.


This 176' long twin barrel box culvert, built in 1964, was originally designed with 3″ weep holes for drainage. Over time, the weep holes failed and backfill material escaped through the hole.

Many of the failed weep holes were plugged to stop soil loss. This resulted in constant high water levels and high pressure behind the walls. With no formal place to drain, the water and soil found other paths through seams and cracks.


The demonstration project installed 54, 4" weep hole filters, preserving the existing structures and extending the asset life.  Because of the project's success, Michigan DOT approve a state-wide special provision for JET Filter's Maintainable Weep Hole Filters.

This innovative technology demonstration project was performed as part of AASHTO's - TSP2 Bridge Preservation Program

Plugged-weep-holeView the final project report.

Preserve your investment! Contact us today for more information:



Back to Blog