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The Future of Wixom Lake. “We’re all in this together”. Why the Lakes exist. The dams at Sanford, Edenville, Smallwood and Secord were built by Frank Wixom in 1925 Wixom owned all the upstream lands that were flooded The flooding created four reservoirs and lots of waterfront real estate
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The Future of Wixom Lake “We’re all in this together”
Why the Lakes exist • The dams at Sanford, Edenville, Smallwood and Secord were built by Frank Wixom in 1925 • Wixom owned all the upstream lands that were flooded • The flooding created four reservoirs and lots of waterfront real estate • Hydroelectric power was a relatively new industry and in its heyday in the 1920s • Dams provide recreational opportunities and flood control that would not exist without them
Federal Government Oversight • The Federal Power Act of 1920: • Established government oversight over power producing dams on “navigable waterways” of the United States • Established the Federal Power Commission to regulate them • Today that agency is the Federal Energy Regulatory Commission (FERC)
Federal Government Oversight • FERC licenses power producing dams • FERC’s regulations require the dams’ owner to perform frequent engineering studies, monitoring, environmental and emergency management and to comply with its dam safety standards
What is the “PMF”? • The Probable Maximum Flood (PMF) is an event calculated by FERC to occur once every 10,000 years • By comparison, the flood of September, 1986 was a between a 50- and 100-year flood event • The FERC requires all “high hazard” dams to be able to safely pass the 10,000-year flood without failing (overtopping) • The Edenville Dam is considered a “high hazard” dam because its failure would likely result in loss of life and property downstream at Sanford Lake
What needs to be done? • Six spillways will be reconstructed to double their capacity to pass flood water • There are 3 spillways at the Tobacco River side of the dam and 3 spillways adjacent to the Edenville powerhouse on the Tittabawassee River side • The total capacity of the six spillways is currently 32,000 cubic feet per second (cfs) (or 14,400,000 gallons per minute) • To comply with FERC’s mandate, the capacity of the six spillways will have to be increased to 64,000 cfs (or 28,800,000 gpm)
Spillway Comparison Current configuration of spillways Tittabawassee side adjacent to powerhouse shown; Tobacco spillway is similar
Spillway comparison FERC-Mandated alteration of spillways Tittabawassee side adjacent to powerhouse shown; Tobacco spillway is similar
Spillway construction Example of cofferdam construction
Spillway construction Example of cofferdam construction
Spillway construction Example of cofferdam construction
Spillway construction Example of Cofferdam construction
3-Dimensional Views Existing spillway construction
3-Dimensional Views First concrete pour inside spillway (summer 2013)
3-Dimensional Views New concrete pier extensions (summer 2014) This work takes place “in the dry” behind a sheet pile cofferdam
3-Dimensional Views Stoplogs are placed between piers & rest on new concrete sills Once stoplogs are in place water levels can be returned to normal
3-Dimensional Views Construction work taking place between 2015 and 2016 Existing gate and bridge are removed More concrete is poured in the base of the spillway
3-Dimensional Views Construction work taking place between 2015 and 2016 Concrete rollaway slabs and most of upstream barrel arches are removed
3-Dimensional Views Construction work taking place between 2015 and 2016 New concrete crest is poured
3-Dimensional Views Construction work taking place between 2015 and 2016 Concrete overlay is placed over entire pier structure
3-Dimensional Views Construction work taking place between 2015 and 2016 New bridge is constructed
3-Dimensional Views Tobacco Spillway to be completed in 2016 New gate is installed and stoplogs are removed
3-Dimensional Comparison Existing spillway Modified spillway
Why will the lake be lowered? • Half of the dam’s spillway capacity will be out of service while the sheet pile cofferdam is in place • The drawdown provides a “buffer” as a precaution so that the spillway structure that is still open can be used to pass enough flood water to avoid dam failure • 30 years of data show that rainfall is least in July, August and September • While rare, floods have been known to happen in summer • FERC requires it for dam safety
When will the lake be lowered? • Starting in June, 2014 Wixom Lake will be drawn down 8 feet for five months (until October) then returned to normal levels • The reservoir will be maintained at normal levels during 2015 and 2016 while construction continues behind the stoplogs • The second draw down will start in June, 2017 when construction begins on the pier extensions for the Tittabawasse spillway for five months, then Wixom Lake will be returned to normal levels in the fall and maintained thereafter
Will this construction increase the production and income of the dam? • No. The PMF spillway modification will only increase the dam’s ability to pass flood waters • During the drawdown for the Tobacco spillway construction in the summer of 2014, production and income at the Edenville powerhouse will actually be significantly reduced • The turbines are not able to run at full capacity with so little head water
Will this construction increase the production and income of the dam? • No. When the Edenville (Tittabawassee) spillway is under construction in 2017, electrical production will be shut down completely; there will be no income during this time from the Edenville dam • The entire spillway and powerhouse structure will be blocked off with a cofferdam for five months • A powerhouse is designed at the Tobacco spillway, but its cost is not included in the spillway alteration construction estimates • this could be privately financed due to its income-production capacity
Is the dam safe? • Yes. Boyce complies with all FERC-mandated dam safety requirements • The Edenville dam is well maintained and is structurally sound • Dam stability improvements and reinforcing are ongoing for the safety and longevity of the dam • Boyce has spent over $1.3 million over the past six years on these improvements at Edenville Dam alone
The PMF is an “unfunded federal mandate” • Boyce Hydro Power has negotiated with FERC for more than seven years to reduce the PMF requirement • Engineers succeeded in reducing the requirement, but FERC will not eliminate it • There is no Federal funding or grant money available to Boyce to pay for the PMF alterations • The PMF Spillway alteration does not qualify for federal or state grants
Why can’t Boyce pay for the PMF? • Net income after expenses from the operation of the Edenville dam is less than $200,000 per year • The cost of operations continues to rise, i.e. materials, gasoline and diesel fuel, and employee benefits such as health insurance • Private financing is unavailable • The dam is already encumbered with debt • The PMF spillway alteration does not increase income
Why can’t Boyce pay for the PMF? • Boyce is paid 30% less by Consumers than the average of all the other 14 independent hydroelectric power producers in the state • The rates being paid to Boyce by Consumers Energy for energy production have not increased in the last seven years • There is continued downward pressure from Consumers on rates, despite increases in energy prices to end users
We’re all in this together • The cost of this federally-mandated spillway modification project is currently estimated to exceed $8 million • Boyce does not have the capital to support such a massive expense • Grants are also unavailable at this time • The State provides some grant money to remove or repair smaller dams, but not to comply with Federal mandates
We’re all in this together • We all want the same thing: the guaranteed future of Edenville dam and Wixom Lake • Boyce, waterfront residents, and other businesses depend on the reservoir • Public financing is one alternative to pursue • Let’s work together to find a solution to this looming problem
Call to Action • Strive to obtain and distribute accurate information • Get involved with local task forces that have been established to work with our elected representatives • We will overcome these issues and ensure the future of Wixom Lake for generations to come by working together