Posted on June 12, 2023
The U.S. Army Corps of Engineers, Detroit District (USACE) is currently utilizing 24-hour dredging in Grand Haven, Michigan during favorable weather to remove shoaling blocking Grand Haven Harbor from commercial traffic. The project is expected to be completed in mid-July.
Severe weather and minimal ice cover during the winter led to increased shoaling in several harbors on Lake Michigan this year, blocking large commercial vessel traffic. Grand River commercial docks are struggling to receive shipments due to the unexpected shoaling.
The King Co., Inc. of Holland, Michigan is on-site and contracted to clear 141,000 cubic yards of sand from the federal channel at Grand Haven, just beyond the pierheads. The material will be placed 7,000 to 10,000 feet north of the north pier onto the beach and into the nearshore area between the Ordinary High-Water Mark (OHWM) and the most-landward 12 feet depth contour in the lake. The placement area borders the Ottawa County North Beach Park and several properties along North Shore Drive.
The contract, awarded Feb. 28, required the work to begin in Holland and Grand Haven harbors when the weather allowed in the spring using hydraulic dredging for speed and cost. Unusually windy and wavy conditions during March and April delayed dredging work in Holland.
Due to specialized equipment used in hydraulic dredging, waves as small as 1.5 feet can create dangerous conditions for the crew and cause work to be suspended.
Unprecedented shoaling – the movement of sand into the channel – led to additional dredging in Holland, where King Co. dredged 90,000 cubic yards of material in May before mobilizing their equipment to Grand Haven Harbor.
“The team really pulled together to address the rapidly changing conditions at both Grand Haven and Holland harbors,” said Elizabeth Newell Wilkinson, Grand Haven Resident Engineer. “We’re dredging later than planned but looking forward to the safe opening of the harbor to commercial shipping very soon.”
In Grand Haven, dredging will now continue 24 hours a day to maximize efficiency during favorable weather. The King Co. will maintain all necessary lighting and safety procedures to be able to continue working through the night. As much as possible, bulldozing operations will be paused during the nighttime hours to avoid disrupting nearby residents. Every few hours, the bulldozer will be required to add pipe extensions to prevent over-piling of material.
Dredged material is pumped from the dredging vessel through a 16-inch pipeline and discharged into the nearshore area. This material has been sampled and tested to ensure it is clean and more than 90% sand. Sand and water are pumped through the pipeline and create an almost quicksand-like condition directly around the pipe outfall.
All residents and beachgoers should avoid getting close to the pipeline at the discharge point. After discharging, a bulldozer will grade the sand.
Safety cones will be posted near the areas of active bulldozing and pipeline discharge. Residents will still be able to use the beaches except for those areas designated as off-limits.
The U.S. Army Corps of Engineers, Detroit District, maintains a navigation system of 81 harbors and channels joining lakes Superior, Michigan, Huron, St. Clair and Erie.
The Detroit District provides vital public engineering services in peace and war to secure our Nation, protect the environment, energize our economy and reduce risks from natural disasters.
For more details, contact Detroit District Public Affairs Specialist Brandon Hubbard, (313) 500-3251.
