The U.S. Army Corps of Engineers (USACE), Detroit District, under its operations and maintenance authority, proposes to construct a seepage filter along the east dam embankment (connecting dike) for De Pere Dam on the Fox River. The project site is about 7 miles upstream from Green Bay in Brown County, Wisconsin. Seepage paths have been detected in the embankment and some sinkholes have formed. The proposed filter would prevent movement of material out of the embankment, which could eventually result in undermining of the embankment. Other alternatives considered include no action and construction of a steel sheet pile wall along the embankment. The selected action is to construct a seepage filter/revetment along the river side of the embankment.
An Environmental Assessment (EA) and Clean Water Act Section 404(b)(1) Evaluation of the Effects of Placing Fill in the Waters of the United States are attached to this public notice. Any person who has an interest that may be affected by the proposed in-water placement of stone may request a public hearing. The request must be submitted in writing within the comment period of this notice (as described below) and must clearly set forth the interest that may be affected and the manner in which the interest may be affected by this activity.
Environmental review indicates the proposed seepage barrier/revetment would not result in significant adverse environmental effects, nor would it be expected to result in significant cumulative or long-term adverse environmental effects. Adverse effects would be minor, limited primarily to short-term noise and air emissions from equipment operation, minor disruption of local wildlife and loss of any benthic (bottom dwelling) organisms in the immediate work area. The proposed seepage filter requires a toe section on the bedrock of the riverbed, which results in a loss of approximately 0.12 – 0.16 acre of potential lake sturgeon spawning habitat; however, spawning would not be significantly impacted as the sturgeon would continue to spawn on the adjacent bedrock river bottom.
The project is beneficial in that it will reduce entry of fine-grained material into the waterway from seepage paths through the embankment and will help stabilize the embankment to prevent embankment failure. Embankment failure would result in loss of the pool and navigability and likely catastrophic loss of, or damage to, nearby infrastructure such as the walkway, lock-operators house, and dam abutment.
The proposed seepage blanket is expected to have minimal effect on the coastal zone of Wisconsin, and would be consistent to the maximum extent practicable with the State of Wisconsin Coastal Zone Management program. Water quality certification under Section 401 of the Clean Water Act is being processed under State Chapter 30/31 regulations.
This Public Notice is being issued pursuant to the National Environmental Policy Act to the
Environmental Protection Agency, U.S. Fish and Wildlife Service, the State of Michigan, other Federal, state, and local agencies, tribes and tribal interests, and other interested groups and individuals for the purpose of providing information and to solicit comments and views relative to the proposed construction activity. Comments you may have concerning the proposed activity should be made within thirty (30) days from the date of this notice. If no comments are received by the end of the thirty (30) day review period, it will be assumed that you have no comment. Please direct your comments to:
U.S. Army Engineer District, Detroit
ATTN: CELRE-PLE (Charles A. Uhlarik)
477 Michigan Ave.
Detroit, Michigan 48226-2550
Any person who has an historical or cultural interest that may be affected by the proposed action may submit written comments within the comment period of this notice (as described above), clearly describing what historical or cultural interest may be affected by this activity.
Following the comment period and a review of the comments received, the Detroit District, USACE, District Engineer will make a final decision regarding the necessity of preparing an Environmental Impact Statement (EIS) for the proposed seepage blanket/revetment for the east dam embankment at De Pere, Brown County, Wisconsin. Based on the conclusions of the EA, it appears that preparation of an EIS will not be required; therefore, a preliminary Statement of Findings/Finding of No Significant Impact has been included in the EA.