Buffalo Lake Dam Project

Update date Meeting

June 30, 2012

Purpose of this Meeting

• Provide update on status of the project

• Describe the timeline for the project

• Questions and Answers

SITE OVERVIEW

NorthBuffalo Lake

Existing PrimarySpillway

Existing Lockand Gates

Existing Boat Launchand Parking

Existing Embankment

How Did We Get here

• Primary cause - Flood of June 2008 and re-routing of traffic over the “Dredge Bank”.

• DNR orders the road closed and to fix, replace or remove dam by 2012.

• The “Dredge Bank “ was constructed in 1855

How Did We Get Here

• 2010-2011 alternatives evaluation - AECOM study

• January 22, 2011 public presentation• State Bldg. Commission Approval - April 2011• Included in state FY2011-2013 Budget• Mead and Hunt contracted June 2012

• Condition of Existing Structures and Embankment

• Present Conceptual Alternatives and Range of Costs

• Conceptual Public Use and Recreation Improvements

• Discuss Buffalo Lake Drawdown and Potential Construction Impacts

• Questions

January 22, 2011 Meeting Summary

Condition of Lock and Sluice Gates

The lock’s stone walls are generally in good condition.

Voids in the lock floor were observed by the diver.

Upstream face of sluice gates.

Gates are in fair condition.

Corrosion and some pitting is present.

Condition of Primary SpillwayDownstream surface of concrete capped spillway.

Generally in good condition.

Note additional flash boards placed for dive inspection.

Left Abutment Wall - Downstream

Constructed of stone masonry.

Stonework is failing.

Wall is in poor condition.

Condition of Primary SpillwayRight Abutment Wall

Better condition than left wall.

Note steel tieback whalers.

Tuck pointing of masonry joints.

Right Abutment Wall

Erosion of lower joints.

Condition of EmbankmentSouth Portion of Embankment Looking West

Upstream slope very steep

Rip rap cover is sparse with no bedding to prevent erosion.

North Portion of Embankment Looking South

Rip rap cover is sparse with no bedding to prevent erosion.

Condition of EmbankmentDownstream Slope of Embankment in South Portion.

Steel probe pushed in 4 feet by hand.

Upper zone of embankment is very loose.

South Portion of Embankment

Large sinkhole repaired in 2008.

WDNR Conclusions and Preferred Options

Montello Dam Feature Preferred Option Range of Costs

Sluice Gates and Lock Chamber

Replace Existing Gates at Current Location (B) $400,000 - $450,000

Primary Spillway Replace Entire Spillway and Include a Fish Passage Structure (B)

$2.5 - $3.0 Million

Embankment Option D: Two-way Road and Walking Path from North End to Existing Boat Launch LocationPedestrian / Bike Path on South Half (D)

$5.0 - $6.0 Million

Public Use and Recreation Enhancements

Launch, Piers, Wharfs, Benches, Lights, Portage $350,000 - $400,000

Project Total $8.25 - 9.85 Million

The preferred options identified below may change based on funding, public input, and final design.

WDNR Conclusions and Preferred Options (Continued)

What to Expect:

•Most Likely Need Full Drawdown and a Partial Breech of the Primary Spillway

•Best Case – Begin Drawdown After Labor Day – Finish Construction the Following Summer or Fall

•Best Case – Begin in 2012 – Could be 2013

•Selected Options Should Allow Concurrent Construction of Gates, Spillway, and Embankment

Project Components

• Install Slurry Cutoff Wall• Embankment Stabilization• Spillway Replacement• Replace Sluice Gates• Fish Passage• Boat Landing• Public Use Facilities

Projected Schedule – per Mead & Hunt and DNR

• Contract Signed - June 2012• Begin Drawdown – September 4, 2012• Provide Review Documents – September 2012• Provide Final Design Documents – January 2013• Advertise for Bid – February 2013• Bid Date – March 2013• Contract Award & Construction Start - May 2013• Drawdown Dependent Construction Complete, Refill

Buffalo Lake – May 2014• Substantial Completion – November 2014• Project Close Out – December 2014

Next Steps

• June 30, 2012 - public update meeting

• August 18 - meet with Lake District and EA comment period on drawdown

• Late September - public meeting on proposed final design

Thank You!

Questions?