Ceresco Dam Removal Project. Michigan Watershed Summit March 25, 2015 Luke Trumble, P.E., MDEQ-WRD Jay Wesley, MDNR-Fisheries

Transcription

1 Ceresco Dam Removal Project Michigan Watershed Summit March 25, 2015 Luke Trumble, P.E., MDEQ-WRD Jay Wesley, MDNR-Fisheries

2 Outline Overview of Ceresco Dam History Public Process Funding Dam Removal Ecosystem Benefits Ceresco Dam Removal Process

3 Overview Located on the Kalamazoo River in Calhoun County Between Marshall and Battle Creek Michigan Dam ID No. 497 Regulated under Part 315 Low Hazard Potential Earth/concrete gravity structure Retired hydroelectric dam Structural Height of 23 feet Hydraulic Height of 17 feet 10 feet of head, 7.5 feet of freeboard 488 feet long, with 180 foot spillway 75 acre impoundment

4 Overview Powerhouse Residence Gated Spillway Needle Section Overflow Spillway Spillway Apron

5 75-acre impoundment Long and narrow Average depth = 3 feet Adjacent parcels mostly private Overview

6 Current hydropower dam constructed in 1906 by Commonwealth Power Company (now Consumers Energy) Operated until 1960 s Maintained 17 feet of head and 250-acre impoundment Historically a Significant Hazard Potential dam Drawn down 3 feet in 1978 due to structural concerns at powerhouse Sheetpile wall and 75 feet of fill placed upstream of powerhouse Drawn down an additional 4 feet in 1990 due to structural concerns at principal spillway Concrete and foundation repairs made at that time Hazard potential reduced to Low due to reduced head History

7 History (Complicated) Several ownership changes Several applications to FERC to restore hydropower generation All denied/revoked at various stages Jurisdiction bounced between FERC and DEQ Movement of overflow spillway Repaired in 1990 Coring to bedrock, concrete piles Major rehab of southern section Inspected in 1993 under Part 315 Fair condition assessment Significant deterioration of concrete piers, apron, needle section Seepage at spillway apron No other inspections performed No other major repairs/restoration completed No enforcement action taken Jurisdiction was uncertain Low hazard potential made it a low priority

8 Dam was purchased by Tri-State Holdings, LLC (subsidiary of Enbridge Energy) in 2013 Impoundment to be dredged as part of the 2010 Line 6B rupture clean up efforts Proposed to remove Ceresco Dam and restore a natural river channel through the former impoundment as mitigation for environmental impacts related to the spill Design, dredging, partial removal of the dam to be completed in 2013 Full removal and river restoration to occur in 2014 History (Recent)

9 Public Involvement DNR meeting with local residents DNR/Enbridge Public Meeting Two DNR/DEQ/Enbridge Public Hearings

10 Dam Removal Funding 100% Enbridge Other Dams Local funding/match Foundations DNR Aquatic Habitat Grant DNR Dam Management Grant USFWS Fish Passage Grant USFWS GL Fish Habitat Grant Great Lakes Fishery Trust GL Fish and Wildlife Restoration Act

11 Why is DNR interested in Removing Ceresco Dam? National Movement (American Rivers) DNR-Fisheries Policy Fish Biologist Recommended removal in Conversations with Dam Owner in 2002 Kalamazoo River Assessment 2005 Enbridge, DNR, DEQ Agreement 2013 Opportunity to remove oil and complete mitigation project.

12 Ecosystem Benefits Improve Movement of Biota Improve Riverine Habitat Natural Flow Regime and Sediment Transport Improve Water Quality Decrease Water Temperature Improve Nutrient Cycling and Movement Natural Channel Morphology

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14 River Changes Wetlands acres of wetland conversion Dam

15 River Changes Moderate Changes (short-term) Major Changes (long and short-term) Minor Changes

16 River Changes Fish and Wildlife Community Aquatic Species Lake River Terrestrial Species Wetland Edge Floodplain Corridor

17 Dam Removal And Restoration Process Phase 1 Pilot Channel Dredge Phase 2 Dam Notch Phase 3 River Restoration

18 Permitting Permitted in 3 phases Phase I P Dredging of submerged oil contaminated sediments and 70 foot wide pilot channel Installation of boom and curtain containment along pilot channel Install sheetpile cofferdams and weirs for containment and flow control during dredging operations Begin channel and floodplain restoration in areas to be exposed by drawdown in next permitting phase

19 Phase II P Construct a rock buttress immediately upstream of the dam Cut a notch in the overflow spillway using an excavator mounted hydraulic hammer Lower the spillway crest 5 feet Permanently drawdown the impoundment at a rate of 0.5 feet per day Install riprap scour protection at 12 th Street Bridge Revised to include additional notch to spillway apron elevation and removal of gated spillway superstructure Additional drawdown required to dewater impounded sediments Gate piers became unstable Permitting

20 Phase III P Complete removal of dam Powerhouse, needle section, and right abutment to remain Complete drawdown of the impoundment Excavation of full-width channel Construction of riffles and vanes Overbank grading to establish floodplain bench Floodplain vegetation Seeding and live plantings Permitting

21 Channel Restoration Approximately 2 miles 70 ft wide to 110 to 130 ft Creation of bankfull floodplain bench Riffle/Pool Creation Bank Protection Structures Native plantings

22 Pilot Channel/Containment

23 Pilot Channel/Containment

24 Pilot Channel/Containment

25 Pilot Channel Dredging

26 Pilot Channel/Containment

27 Pilot Channel

28 Channel Restoration

29 Channel Restoration

30 Channel Restoration

31 Channel Restoration

32 Sediment Movement

33 A River Restored

34 Thank You! Questions?