Stony Island
Funded by: U.S. Environmental Protection Agency, administered through the National Oceanic and Atmospheric Administration (NOAA)
Project Budget: $8,000,000
Start Date: August 2013
End Date: December 2018
Stony Island is part of the "Conservation Crescent" surrounding the lower end of Grosse Ile and is well recognized for its biodiversity. However, decades of erosion greatly reduced the wetlands surrounding this island. Breakwater structures that once protected the island's north and south bays were nearly eliminated. This project involved reconstructing these breakwaters to protect the island’s valuable coastal wetlands from further degradation.
Stony Island includes 52 acres of uninhabited land in the lower Detroit River and is owned and managed by the Michigan Department of Natural Resources (DNR) through the Pointe Mouillee State Game Area. The Island's north and south bays have capacity to provide tremendous habitat for local fish stock, including important spawning and nursery waters for muskellunge, northern pike, pumpkinseed sunfish, largemouth bass, yellow perch, channel catfish, and bullhead. Historically, lake sturgeon, lake whitefish, white bass, smallmouth bass, walleye and rainbow smelt populations spawned in areas surrounding the island, and this project aids in this activity's recovery. Mink and various turtle species reside in the island's complex association of palustrine emergent and shrub wetland habitats. The area provides a productive location for rare and transient waterfowl along with nesting and feeding areas for many species of ducks and wading birds. The island’s wetlands and tree stand between the two bays contain the river's largest Great Blue Heron rookery with over 140 active nests. This restoration project protects the island from continued habitat degradation, allows areas that have seen loss to recover, and stimulates expansion of quality habitat.
Project Scope: An initial grant award from NOAA in the summer of 2013 combined early investigations at Stony and Celeron Islands into one project involving intense information gathering and analysis. Environmental Consulting and Technology, Inc. (ECT) was engaged by FDR to assist the Detroit River Public Advisory Council, DNR and project stakeholders in the planning, design and engineering process. Intense information gathering was conducted to inform the development of various design alternatives for both islands. Once preferred alternatives were identified and vetted through governmental agencies and the public, the designs were further developed into preliminary construction documents and submitted for permit to the Michigan Department of Environmental Quality (later renamed Michigan Department of Environment, Great Lakes, and Energy) and the U.S. Army Corps of Engineers. With additional funding by NOAA, both projects were independently advanced into construction.
E. C. Korneffel Company was selected through a competitive bidding process to construct the Stony Island project. Work began in the summer of 2016 and was completed in the spring of 2018. Habitat improvements were designed to protect the north, west and south sides of the island. These included creation of nearly 3,500 linear feet of rock shoals and 550 LF of shoal islands, supporting vegetation and selective habitat, while protecting and promoting development of over 50 acres of backwater – a calm, vegetated water zone suitable for fish spawning and nursery activity. Within the south bay, a series of depressions provide deeper water habitat. Granular material and native plantings are placed along the backside of one shoal, providing shoreline habitat.
A fish nursery area was created on the inside of the south habitat shoal by excavating a v-shaped area approximately 30’ wide by 200’ long to a water depth of about 10’. The excavated material was used to construct a submergent shoal near the depression to block current around the depression. In the depression, a 1-foot stone/gravel base was added to provide voids for small fish fry seeking protection from predation along with some larger stones to provide hiding and conjugation areas for larger fish. Upland habitats (snake hibernacula, turtle nesting areas and other structural habitats) were completed on the island shore. Public access to the restoration site greatly benefits birders, fishermen and hunters using the island and surrounding waters for recreation.
Post construction monitoring followed throughout 2018 to document any changes in fish and wildlife populations. Although no dramatic increases in these populations were observed in this first year following construction, they are anticipated to grow over time as the restoration work becomes established.
Granular material along the calm-water side of one of the shoals accompanied by native plantings provides a new shoreline habitat. Restoration of a sandbar on the island’s northeast side creates a nesting, barrier beach habitat. Other habitat structures and features are included to promote habitat development, diversity and protection.
E.C. Korneffel Company was selected through a competitive bidding process to construct the project. Work began in the spring of 2018 and was completed by the end of 2019. Post-construction monitoring will follow in 2020 to document changes in wildlife populations based on the restoration work.
Project Outputs/Outcomes: The project provides important ecological outcomes such as 1) re-establishment of spawning and nursery habitat for commercial, sport and forage fish species; 2) revitalization of coastal wetlands; and 3) protection of terrestrial resources within the watershed. This was primarily achieved by constructing protective shoals, which include:
550 linear feet of protective shoal “islands” (at island’s north end)
550 linear feet of tern habitat (included with above)
4,490 linear feet continuous protective shoal (at island’s north, west and south side)
A variety of habitat design elements are incorporated to provide multiple niche habitats in support of existing fish and wildlife species. These include:
37 habitat structures for mudpuppies
2 structures for mudpuppies and mussels
61 basking logs and log bundles for turtles and fish
5 turtle nesting areas constructed of sand
1 snake hibernacula
50 acres of calm backwater for fish spawning and nursery activity
11 acres of vegetation management including invasive species control
The Stony and Celeron Island habitat restoration projects are recognized as major steps in completing habitat re-construction among the islands in the lower Detroit River.
Project Data
These data and related items of information have not been formally disseminated by NOAA, and do not represent any agency determination, view, or policy.