History of Grassy Island

Grassy Island Lighthouse

The photos below visually represent the changes that Grassy Island has undergone in the past 45 years.  

  • Pre-1955

    The U.S. Coast Guard had jurisdiction over Grassy Island, and used it for the installation of navigation guides.

  • 1955

    The Army Corps of Engineers (COE) began studies for the disposal of dredged materials from the Rouge River, including diking an area in the Detroit River surrounding Grassy Island.

  • 1958


    The U.S. Coast Guard issued a permit to the COE, allowing the COE to deposit spoil materials from dredging operations.  Photo - Grassy Island, pre-expansion dike construction, 1985  

  • 1959

    The COE began diking 300 acres around Grassy Island for the disposal of polluted dredged sediments primarily from the Rouge River.  On October 7th, at a meeting with the COE, U.S. Bureau of Sport Fisheries and Wildlife, and Michigan Department of Conservation, Congressman John Dingell, Jr. negotiated an agreement in which the COE could continue construction of the Grassy Island disposal facility, but only 72 of the original 300 acres would be diked.

  • 1960

    Mr. Dingell introduced Federal legislation to designate Grassy Island as a National Wildlife Refuge. The Department of the Interior agreed that when it received jurisdiction over the Grassy Island area, it would not object to the COE continuing to use the 72 acre disposal facility.

  • 1961

    Wyandotte National Wildlife Refuge was established by the U.S. Congress with Public Law 87-119.  It includes Grassy Island and surrounding shoals out to a water depth of 6 feet and extending approximately 3 miles downstream of Grassy Island and included the Mamajuda Shoal. 

  • 1967


    The COE completed the dikes of the Grassy Island disposal facilty to create a rounded kidney shaped island.  The original dike was 6 ft above water level and was built from excavated river bottom material composed of uncompacted clay, sand, and gravel.  Construction of the Grassy Island disposal facility preceeded Public Law 91-611 (1970) which initiated the Great Lakes confined disposal facility (CDF) program and sets forth the use of confinement technologies.  The facility was originally built without engineered dikes or many features of later CDF structures that included liners, caps, and riprap protection.  Photo - Grassy Island, late 1960s  

  • 1971


    Capacity was expanded by the construction of a 20 foot dike inside the original 6 ft dike, and the interior of the island was bisected into north and south cells by an interior dike. Photo - Grassy Island, post expansion dike construction, 1972  

  • 1982

    Last year that dredged spoils were deposited on Grassy Island disposal facility. The COE deposited over 3 million cubic yards of dredged spoils during the 1961-1982 years of operation of the Grassy Island disposal facility. In November, a 25’ section of the south dike wall ruptured during disposal operations. 

  • 1985-1986


    The dikes adjacent to the navigation channel were repaired and reinforced with filter cloth and riprap revetment to prevent failure of the structure due to riverine and navigational forces. Grassy Island remains uncapped. Photo - Grassy Island, 1985 

  • 1988-1999

    Personnel from the U.S. Wildlife Service and U.S. Geological Survey perform studies to identify and quantify contaminants in the soils, sediments, and plants on and surrounding Grassy Island. Additionally, birds utilizing the island were collected for contaminants analysis.  Click here for a description of available reports.

  • 2001

    The Detroit River International Wildlife Refuge Act (Public Law 107-91) was passed.  Grassy Island was incorporated into the Detroit River International Wildlife Refuge, and is part of the first international refuge in North America.