Saginaw River Dredge Disposal Project at Saginaw Bay, Michigan
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' SAGINAW RIVER DREDGE DISPOSAL PROJECT AT SAGINAW BAY, MICHIGAN FINAL ENVIRONMENTAL IMPACT STATEMENT FEBRUARY 1 ^4/ PREPARED BY U.S. ARMY ENGINEER DISTRICT DETROIT, MICHIGAN STATEMENT OF FINDINGS PROPOSED DREDGE DISPOSAL FACILITY SAGINAW BAY, MICHIGAN I have reviewed and evaluated, in light of the overall public interest, the documents concerning the proposed action as well as the stated views of other interested agencies and the concerned public relative to the proposed dredge disposal fa cility at Saginaw Bay, Michigan. BACKGROUND Construction of the proposed facility is authorized by the River and Har bor Act of 1970 (Public Law 91-611, Section 123) which provides for the confined disposal of polluted materials resulting from maintenance dredg ing of Federal navigation projects. Additionally, in 1970, the Governor of Michigan requested that the Corps of Engineers cease returning polluted dredged materials to the waters of the Great Lakes in Michigan. As part of the planning process for the proposed fa cility, two workshops were con ducted at Bay City in March 1974. These meetings were attended by govern ment representatives, city representatives, environmental groups and the general public. The purpose of the meetings was to provide and exchange information relative to the alternatives being considered for siting the facility. As a result of information generated at the workshops and con tinued coordination with the State of Michiv,—., the Channel-Shelter Island location was selected. THE SELECTED PLAN -The proposed disposal site is located on the southeast side of the Federal navigation channel in Saginaw Bay, approximately two miles northeasterly from the mouth of the Saginaw River. At the present time Channel and Shelter Islands exist at the disposal location, having been previously formed from dredged materials resulting from prior maintenance operations. These islands have not stabilized but have steadily eroded contributing to excessive shoaling in the navigation channel. The proposed confined • disposal facility is generally circular and w ill encompass the two exist ing islands and waters adjacent to them. Dikes to contain the dredged material have been designed to be impermeable and w ill be protected by rubblestone. The 285-acre facility w ill have a capacity for 10 m illion cubic yards of dredged m aterial, the estimated amount for 10 years of maintenance dredging and accumulated backlog. Monitoring of overflow ef fluent by the Corps of Engineers w ill be conducted in accordance with approved procedures and Environmental Protection Agency guidelines. ALTERNATIVES Five alternative sites, in addition to the alternative of no action, were considered during the planning process for the proposed fa cility. Three locations offered were privately owned upland or marsh areas. However, when the pertinent terms for disposal on private lands were explained to the property owners by the Corps, these locations became unacceptable. Further evaluation of additional areas was initiated. Two open water sites, were considered. The Gull Island site, approximately one mile northeasterly from the mouth of the Saginaw River, was considered and rejected due to adverse environ mental and aesthetic effects to adjacent shore property owners. A barrier dike at Nayanquing Point was also' considered and rejected due to limited access which would result in unnecessarily high costs. The alternative of no action would mandate that no periodic maintenance dredging operations be performed. Continuous shoaling of the navigation channel would eventually impede the movement of commercial and recreational vessels dependent on this waterway. Existing public and private water re lated facilities would suffer economically as the channel decreased in its ability to provide safe and adequate navigation. EVALUATION OF THE SELECTED PLAN In evaluation of the selected plan, the following points were considered p e r tin e n t : Environmental Considerations Construction of the proposed facility w ill create 285 acres of upland area in Saginaw Bay, replacing Channel and Shelter Islands and approximately ~200 acres of bay bottomland. The rubblestone dike structure may encourage perch spawning in the area, enhancing sport fishing activities. The dis posal area w ill create a protected area in the bay to the lee of the faci lity. Presently occurring erosion from the existing dredge material islands w ill be eliminated. Confinement of the polluted dredgings w ill eliminate their re-introduction into adjacent waters and over time may assist in up grading both water and sediment quality of Saginaw Bay and nearby tributaries. Social Considerations The selection of this disposal location was made in such a manner to mini mize adverse environmental effects and to confer benefits on the people and community of Bay City as a whole. The creation of a recreational faci lity at the end of ten years time w ill provide to the public additional shoreline in an area of little recreational development. In addition, the Channel-Shelter Island location minimizes objections by shoreline property owners. Engineering Considerations Construction of the facility around the existing dredge material islands w ill serve to eliminate their continuing erosion. Configuration of the dike .structure, as well as materials used in its construction, have been designed and selected to provide an aesthetically pleasing appearance as well as minimize affected areas of bottomlands. Design criteria were also implemented to minimize adverse effects on the flow regime of inner Saginaw Bay. Economic Considerations Construction costs for the proposed facility have been estimated at $20.5 million. The total project cost is approximately $22 million. Annual cost per cubic yard of dredged material is approximately $4.15. Other Considerations The Michigan Department of Natural Resources has expressed its support for the project as proposed. Concurrence for the placement of the facility was also received from the Federal Fish and W ildlife Service and the Envi ronmental Protection Agency. CONCLUSION After giving full consideration to all pertinent data, the expressed opinions of various individuals and agencies and the studies and investi gations referred to above, it is my decision to recommend construction of the facility as described in the Final Environmental Statement. JAMES E . HAYS Colonel, Corps of Engineers District Engineer ' DATE: I concur in the preceding Statement of Findings. WALTER'0 . BACKUS Brigadier General, U.S.A. Division Engineer DATE: _ I concur in che preceding Statement of Findings. FOR THE CHIFF OF ENGINEERS: (D a te ) y. W. MORRIS Major General, USA Director of Civil Works SUMMARY CONFINED DISPOSAL FACILITY FOR SAGINAW BAY, MICHIGAN ( ) DRAFT (X) FINAL ENVIRONMENTAL STATEMENT RESPONSIBLE OFFICE: U. S. Army Engineer D istrict 150 Michigan Avenue Detroit, Michigan 48225 1 . NAME OF A C T IO N : (X ) A D M IN IS TR A TIV E ( ) LEGISLATIVE 2 . DESCRIPTION OF ACTION: Construct a contained disposal facility for polluted dredged materials from Saginaw Bay navigation channel, Bay County, M ic h ig a n . 3 . (A ) ENVIRONMENTAL IMPACTS: Construction of the fa cility w ill create 285 acres of upland in Saginaw Bay, replacing two small islands created by former dredging, and the surrounding bay bottomland and water. Ihis is a commitment of a water resource to another use, loss of associated aquatic communities, and a change in the hydraulic regime. It is expected the prospective island landform w ill create minor changes in the latter and short-term losses in the former, with long-term reinstatement of compar able if not improved values: potential re-establishment of fish habitat in rock dike; upgrading of water quality in bay and Lake Huron through removal of considerable quantities of polluted bottom sediments; creation of a protected area in the bay to the lee of the island for present losers of the area; elimination of continuing erosion from present spoil islands, a source of turbidity and channel shoaling; creation of a potential recrea tion area with resultant increased use of water resources of the bay for people and area w ildlife. Resumption of dredging w ill restore channel project depths and insure safe navigation without loss of shipping capacity which is of significant economic importance to the region and area. (B ) ADVERSE ENVIRONMENTAL EFFECTS: An irretrievable loss of approx imately 200 acres of Saginaw Bay bottomland and open water, with associated aquatic communities, w ill occur. The stone facing of the dike provides a stable substrate for such nuisance growths as Cladophera, a filimentous a lg a e . 4 . ALTERNATIVES: 1 . Gull Island Plan 4 . Inland sites 2 . Nayanquing Barrier Dike 5 . Upland industrial site 3 . Hampton Township Plan 6 . No a c t io n 5 . COMMENTS REQUESTED: The draft environmental statement was circulated to other government agencies and the public for comment. Government Agen cies who furnished comments on the Draft EIS are as follows: Federal Power Commission U. S. Department of Transportation Federal Highway Administration United States Coast Guard Department of Health, Education and Welfare U. S. Department of Interior Environmental Protection Agency State of Michigan Department of Natural Resources Department of State Highways and Transportation Department of State - Michigan Historical Division Bay County Planning Commission Southeast Michigan Council Of Governments Copies of the comment letters are inclosed as Attachment