1. Project Title: Windsor Salt Riverfront Rehabilitation Project
2. Contact
Don Hector, Project Coordinator
Lisa Tulen, Project Facilitator
Ontario Ministry of Natural Resources (MNR)
1023 Richmond St. West, Chatham, Ontario N7M 5J5
P.O. Box 1168 N7M 5L8
Tel. (519) 354-7340; Fax (519) 354-0313
3. Agencies Involved
Great Lakes Cleanup Fund
Windsor Salt Company
Ministry of Natural Resources
Ducks Unlimited
Other possible funding/partnership groups:
Ontario Ministry of Environment and Energy
United States Army Corps of Engineers
Laidlaw Foundations' Great Lakes Protection Fund
Environmental Partners Fund
Wildlife Habitat Council
Great Lakes Institute of Environmental Research
Environment Canada
Department of Fisheries and Oceans
Canadian Coast Guard
Ministry of Northern Development and Mines
Essex Region Conservation Authority
4. Restoration Goal
Phase 1
Wetland and fish habitat creation.
Phase 2
Rehabilitation of shoreline including construction of spawning
channel and ponds for wildlife
and fisheries.
5. Project Type
Phase 1
Offshore island construction.
Phase 2
Shoreline alteration.
6. Background and Rationale
1. To protect the mainland shoreline by reducing wave and wind effects and preventing hardening of the mainland shoreline.
2. To provide increased edge and shallow water areas for fish.
3. To create a calm water area to provide benefits for aquatic macrophyte establishment, nursery, spawning and feeding areas for fish, staging and nesting areas for waterfowl, feeding and loafing areas for herons, etc.
4. To create nesting islands for waterfowl and colonial nesting birds such as terns. Islands may provide predator-proof nesting areas for waterfowl.
Phase 1 - An embayment area within the Detroit River to the south of the Windsor Salt docking terminal (approximately 4.4 ha) is experiencing considerable sedimentation problems due to hardened shorelines and groynes downstream of the cove. This area is shallow (less than 1.5 m) and contains a substantial amount of submergent aquatic vegetation. The shoreline area is presently mowed grass and no salt is retained in this area. One outfall is no longer in use following the installation of a cyclone, a purifier which removes NaC1 from water; the remaining outfall is releasing levels of brine water (NaC1) that are acceptable to Municipal/Industrial Stormwater Abatement (MISA) program standards.
Expected implementation: 1995
Phase 2 - Currently, salt covers most of the shoreline area. The depth of coverage is not known at this time. Some phragmites and low-lying grasses exist along the shoreline. A small mud-flat and narrow creek provide some diversity to the present habitat. A canal intersects the property and provides an inland hydrologic connection. The property north of the canal is separated by a fence from an undeveloped piece of land and is owned by Windsor Salts parent company in Chicago.
Expected implementation: 1996
7. Regulatory Considerations
No approvals at this time:
1. Environmental Assessment- approvals will be necessary for both Provincial Class EA Planning Procedure and Federal Environmental Assessment Review Process, because we were using federal funds (Environment Canada's Great Lakes Cleanup Fund);
2. Fisheries Act- request for review from Department of Fisheries and Oceans July 21, 1994;
3. Navigable Waters Protection Act- request for review from Canadian
Coast Guard July
27, 1994;
4. Flood and Fill Regulations-received review comments November 10, 1994 from Essex Region Conservation Authority, support project, will need work permit for construction;
5. Fill Disposal Guidelines- in the event dredge material is used to cap islands, approval from Ministry of the Environment and Energy.
8. Criteria
A series of small islands of less than 0.05 ha in area constructed adjacent and parallel to a drop off within 100 to 200 m from mainland or larger island. The area must be semi-protected from heavy current and heavy ice flows. The windward side of the islands must be protected with sufficient armour and filter material. The lee side of the islands may be left natural with a very gradual slope (4:1) to encourage vegetation to establish. Islands should be constructed approximately 100 m apart or as the fetch dictates.
9. Project Design
Phase 1 - The project involves the creation of a series of offshore islands to protect an embayment area from fetch, ice and wave action. Approximately 4 ha of wetland will be created within the calm water area on the lee side of the island chain. Offshore islands are being designed to increase sedimentation and ensure that flow is acceptable for establishing wetland vegetation and provide resting and possible nesting areas for waterfowl. The calm water areas created by the islands would also increase the area's potential for fish habitat. Spawning shoals made of gabion sized rock would provide enhanced spawning sites for fish species including walleye on the lee side of the island. The islands will be capped and covered with substrate acceptable as nesting areas for Common Terns or planted with wildlife shrubs or prairie grass to provide nesting areas for waterfowl.
Phase 2 - A physical barrier, such as a clay berm, should be constructed between the salt piles and the river. This berm would separate the area targeted for enhancement from the salt piles and provide topographical diversity to the area. Containment of salt piles is a requirement for stormwater abatement under MISA; the company has hired a consultant to write their MISA proposal for early submission. Containment could be achieved through creation of a physical barrier such as a clay berm around the salt piles. This berm would separate the area targeted for enhancement from the salt piles and provide topographical diversity to the area. A barrier channel could be excavated around the island and adjacent to the barrier berm to provide spawning and nursery areas and provide a hydrologic connection to the more inland portions of the site.
The salt contaminated soil should be excavated and disposed of
in an appropriate location. The location of the fill would be
landscaped so that the elevation of the fill would allow the area
to be inundated by river water and therefore create a wetland
and island complex where the salt
previously existed. The present soil conditions would provide
limited growing conditions for vegetation thus limiting any possible
rehabilitation efforts. During this process a pond that once existed
but has been filled in by salt can be recreated to provide habitat
for waterfowl and fish. A creek could also be created to join
the canal to the recreated pond. The creek will enhance the diversity
of the site.
A series of natural islands could be created adjacent to the shoreline of the site. The islands would provide further shoreline protection from boating traffic and waves as well as providing resting and possible nesting areas for waterfowl.
The U.S. Army Corps of Engineers is presently investigating whether they will be able to provide engineering designs for offshore islands at phase 1. This will involve collecting flow rate and sedimentation data and modelling.
10. Implementation
Phase 1 - Offshore islands will be created by one of two methods. Generic engineering designs are available from the project facilitator. However, at this time, it is unknown whether a borrow pool method will be appropriate due to the possibility of contaminated sediments. The armourstone used in construction will be from the quarry in Amherstburg and is clean material. The islands will be capped and covered with substrate acceptable as nesting areas for common terns or planted with wildlife shrubs or prairie grass to provide nesting areas for waterfowl.
Phase 2 - The salt contaminated soil should be excavated and disposed of in an appropriate location. The location of the fill would be landscaped so that the elevation of the fill would allow the area to be inundated by river water and therefore create a wetland and island complex where the salt previously existed. The present soil conditions would provide limited growing conditions for vegetation thus limiting any possible rehabilitation efforts. During this process a pond that once existed but has been filled in by salt can be recreated to provide waterfowl and fish habitat. A creek could also be created to join the canal to the recreated pond. The creek will enhance the diversity of the site.
A series of natural islands could be created adjacent to the shoreline of the site. The islands would provide further shoreline protection from boating traffic and waves as well as providing resting and possible nesting areas for waterfowl.
A park and recreation area can be created by placing picnic tables in the area, swings and other playground equipment and installing a boardwalk along the creek. Footbridges over the creek as well as the canal would provide access to the property north of the canal. A boardwalk will allow use of the area for nature appreciation and picnics with minimal disturbance of any natural areas created. This aspect of the project will be the responsibility of the company as no direct benefits to the resource exist.
North of the fence separating the Canadian Salt Company from the vacant land to the north of the site, a pond and spawning channel could be created. This area could also be connected to the Canadian Salt Company site via a meandering creek thereby creating a larger site with more diverse habitat potential.
11. Degree of Environmental Intervention
Offshore islands will be constructed by a marine contractor and will likely involve barging and placing material with a back-hoe. Any material used on the offshore islands will be native material including shrubs from native seed or prairie grass from a local source. Appropriate measures will be taken to ensure construction is carried out with the least negative effect including using sediment traps and working during acceptable seasons.
12. Cost
Currently, consultants are being hired to do core sediment analysis with cost unknown at this time. If the Army Corps does engineering for the offshore island design this will be on a 50:50 cost-share basis with actual costs unknown at this time as well. Construction of four offshore islands has been estimated at costing approximately $140 000. The Ontario MNR RAP staff is providing in-kind support through project facilitating including preparation of reports and partnership arrangements.
13. Biological Assessment
The Ontario MNR conducted electrofishing surveys of the embayment area in July. Following island construction a local scuba club will be asked to do some monitoring to observe fish use of habitat. A local naturalist club will be asked to monitor nesting habitat or use by birds. Marsh bird monitoring and amphibian and reptile counts are being coordinated by Brian McHattie for the Detroit River Area of Concern. There is no commercial fish harvest within the Detroit River. Creel surveys were conducted on the Detroit River in 1992.
14. Measures of Success
Future monitoring of the site will aid determining success of the project. Electrofishing will be conducted in the area following island construction and use by wildlife will also be monitored. Establishment of wetland vegetation will also indicate effectiveness of offshore islands.
Success Rating: 1
15. Key References
Ministry of Natural Resources, 1994, draft version, "Survey of Candidate Sites on the St. Clair and Detroit Rivers for Potential Habitat Rehabilitation/ Enhancement".
Correct citation for this contribution:
Hector, D., and Tulen, L. 1995. Windsor salt riverfront rehabilitation project, p. 158-163. In J.R.M. Kelso and J.H. Hartig [editors]. Methods of modifying habitat to benefit the Great Lakes ecosystem. CISTI (Can. Inst. Sci. Tech. Inf.) Occas. Pap. No. 1.