Precast Culverts Flood Mitigation & Pedestrian Safety Solution – Allen Creek Railroad Berm Project

April 22, 2021 1:00 pm

Jeremy Hedden, P.E., Project Manager, Bergmann Associates; Jim Washabaugh, Bridge Product Manager, Northern Concrete Pipe, Inc.; and Q&A panel member Josh Beakley, P.E., Vice President of Engineering, American Concrete Pipe Association

Webinar Documents:
Precast Culverts Flood Mitigation & Pedestrian Safety Solution – Allen Creek Railroad Berm Project - pdf of presentation
Q&A Session - pdf
News - April 22, 2021 - pdf of presentation

Description: “The biggest flood mitigation project in city history” is the description given to this project by the City of Ann Arbor, Michigan. Enclosed in 1926, Allen Creek near Argo Dam in Ann Arbor was seeing frequent stormwater events exceeding its capacity. In addition, overland flows were impeded by the railroad berm which parallels the Huron River, exacerbating the local flooding problem. The same railroad berm also served as a barrier for citizens looking to use the trail system that parallels the river. In 2020 this ABC project addressed both of these issues, using precast concrete culverts to open the berm. Precast culverts were installed under the railroad tracks during the 37-hour outage to address the flooding problem and to enhance pedestrian safety. Combinations of parallel and single runs of varying size and length of precast box sections totaled 680 linear feet for the entire project. This presentation includes design and construction details as well as lessons learned.

Presentation Photos/Graphics:

1) Multiple crews for excavation during track outage

2) Boxes installed during track outage with temporarily exposed fiber optics

3) Working through the night

4) Buried bridge combination of dual storm sewer boxes and pedestrian tunnel

5) Installation of boxes completed; time to backfill

6) Aerial view looking south near the end of the track outage, backfilling prior to reconnecting the tracks

7) Drone view of completed project