Plainwell Dam Emergency Response

In September 2008, continuous heavy rainfall caused significant flooding along Michigan’s Kalamazoo River. Between September 11 and 15, the rising water levels surpassed flood stage, particularly impacting Plainwell, Michigan.
 
This surge raised serious concerns about the structural integrity of the Plainwell Dam. As the floodwaters rose, visible erosion along sections of the dam heightened fears of potential breaches. Logs and debris trapped in front of the dam’s water control structure added pressure and hindered water flow, exacerbating the flooding conditions and necessitating urgent intervention. The severe weather and rising waters also triggered major erosion and flooding in nearby areas, including the construction staging area, demanding immediate and coordinated emergency response measures to protect the dam and mitigate damage.

Our team served as a subcontractor to Arcadis on this heavy civil construction project. The scope encompassed mobilization, clearing and grubbing, construction of access roads and staging areas, installation and maintenance of the Stormwater Pollution Prevention Plan (SWPPP) and erosion control measures, excavation dewatering, removal of 30,000 cubic yards of PCB soil/sediment, waste transportation, installation and operation of a temporary water treatment system, and final grading of removal areas.

Continuous rainfall from September 11 to 15 raised the river to flood stage, prompting crews to implement emergency measures to safeguard the Plainwell Dam and mitigate damage along adjacent river segments. For 11 consecutive days, crews worked around the clock under extreme conditions to preserve the Plainwell Dam. Team members utilized hydro-blasters to clear logs and debris from the structure, easing pressure and facilitating water level reduction.

The flooding had severely eroded an island between two dam sections, flooding the staging area. Crews erected five-foot berms and a gabion buttress to minimize erosion on the island. Initially, riprap was laid down as a base, followed by the placement of gabion baskets filled with over 150 yards of concrete.

By the seventh day from the onset of the event, all gabion baskets were securely in place and capped with concrete. Jersey barriers were installed with a crane on the seventh and eighth days. These efforts persisted until September 22, 11 days after the rains began on September 11.

Throughout this intense operation, the crew operated without incident or injury, later earning community acknowledgment for saving the Plainwell Dam. Their prompt removal of debris and reduction of water control structure pressure restored the dam’s stability. Installation of the gabion buttress and riprap further reinforced the dam, preventing additional erosion.

By clearing logs and debris, the team lowered water levels and minimized flooding in nearby areas, safeguarding both the dam and surrounding properties.

Erosion control measures preserved the local environment, stabilizing riverbanks and reducing soil erosion. The team’s proactive efforts helped protect the Plainwell community by averting a potential dam breach and received gratitude and recognition from residents.

Throughout the 11-day operation, the crew upheld efficiency and safety, showcasing dedication to excellence in disaster response. The project’s success emphasized our team’s readiness for future flood management and critical infrastructure repair. Community recognition underscored the substantial impact of this project.