Heath Delzell

1
IDNR Engineering

• Heath Delzell Engineering Bureau

Progress to Date and Timeline for Project
Completion Design and Construction Obstacles
2
Construction Activities

• Phase 1 Dam and Spillway Renovation
• Phase 2 - In-Lake Construction
• Sediment Retention Basins
• Sediment Removal
• Shoreline Armoring
• Universally Accessible Fishing Pier
• Phase 3 Boat Ramp and Parking Lot

3
Progress Phase 1

• History
• 1991 Voids filled under spillway
• 2007 Contracted French-Reneker Associates to
  determine cause
• 2008 F-R concluded leak in weathered bedrock
• Solution Remove weathered bedrock
• Status
• F-R Design complete and permitted for
  construction
• Funding has been secured
• Currently out for bids Letting date October 21,
  2010

4
Timeline Phase 1

• Winter 2010
• Early Start Date December 1, 2010
• Portion of dam to be removed
• Tree Clearing
• Concrete Removal

5
Timeline Phase 1

• Spring-Summer 2011
• Excavate Core Trench
• Construct Principal Spillway Outlet/Drawdown Pipe
• Place Embankment Fill

6
Timeline Phase 1

• Summer-Fall 2011
• Place Embankment Fill
• Construct Principal Spillway Inlet
• Auxiliary Spillway Grading
• Close Drawdown Pipe
• Winter 2011 No Construction
• Spring 2012
• Final Grading
• Project Complete May 31, 2012

7
Progress Phase 2

• Sediment Retention Basins
• Upper Arm Basin
• Preliminary Design
• Designed as a Sediment Pond
• Filled with Dredge Material
• 1-2 feet deep
• State Contract for completion
• Finish Design
• Apply For Permit
• Wetland Mitigation Plan

8
Progress Phase 2

• Sediment Retention Basins
• Campground Arm
• Design Complete
• Increasing Dam Height
• Same function as Upper Arm Basin

9
Progress Phase 2

• Sediment Removal
• Design Complete
• Removing sediment via mechanical means
• Scrapers, Bulldozers, Excavators, Etc.
• Shoreline Armoring
• Design Complete
• Placing Riprap in normally inaccessible locations
• Universally Accessible Fishing Pier
• Design 95 Complete

10
Timeline Phase 2

• Winter 2010
• Design and permit application complete January 1
• Wetland mitigation
• Spring 2011
• Bid Letting March 17, 2011
• Early Start Date May 1, 2011
• Summer-Fall-Winter 2011
• Construction
• Spring 2012
• Final Grading and Seeding
• Project Completion March 15, 2012

11
Progress Phase 3

• Boat Ramp and Parking Lot
• Design is 25 complete
• Schedule dependant on Phase 2
• 1-2 Months for construction

12
Construction Obstacles

• RAIN!!!
• Dam construction would slow
• Large storms can severely erode a partially
  constructed dam
• Sediment removal would stop
• Green Valley lt10 complete

13
Construction Obstacles

• Perspective

55.3
54.3
48.4
44.0
40.5
Annual Precipitation for Brighton (inches)
30.2
1991 / 2008 1992 / 2009
1993 / 2010
14
Conclusion

• Dam construction begins in December
• Phase 2 starts Spring 2011
• Boat Ramp starts Fall 2011 or Spring 2012
• All phases should be complete and the lake nearly
  full by the end of May 2012