Document ‘B’
GMEC
Gosling & McClintock Environmental Consultants
To:
Mr. Dennis Will
Butler County Administrator
200 River Road
Butler Springs, MI 44444
Mr. C. Ben Moorhead
Butler Springs City Manager
200 River Road
Butler Springs, MI 44444
Re: Potential for Hydroelectric Power Generation at the Green River Dams
Dear Sirs:
This letter represents a summary of the hydroelectric potential of the Green River
dams, in particular the power generation potential for Jackson, Whitewater and Pine
Valley dams (Figure 1). With a height of only 10 feet, the Bridge Street dam was
never intended to produce hydroelectric power. The study was completed after
reviewing previous studies, conducting independent measurements, and preparing
independent cost estimates.
Table 1: Green River Dams
Miles from
Dam
Age
Fish
River Mouth
Height
(years)
Passage
Bridge St.
1.5 miles
10 feet
143
Yes
Jackson
5.3 miles
32 feet
80
No
Whitewater
6.1 miles
56 feet
80
Pine Valley
18.5 miles
46 feet
80
Dam
Purpose
Maintain level of
Pooled
Acres
Condition
350
Good
Hydroelectric
40
Good
No
Hydroelectric
104
No
Hydroelectric
191
Butler Lake
Insufficient
spillway
Insufficient
spillway
The process of restoring power generation at the dams starts with the licensing
process administered by the Federal Energy Regulatory Commission (FERC) and
would require several improvements to the dams and spillways. We estimated the
cost to repair and restore hydroelectricity generating capacity at all three dams could
range from $8,260,000 to $15,030,000. The revenue estimated from the sale of
electricity from the three dams is approximately $8,600,000 (Present value over 30
years). The tasks associated with restoring hydroelectricity and the costs are
summarized in Table 2.
Table 2. The tasks and probably costs necessary to restore hydroelectric power
generating capacity at Jackson, Whitewater and Pine Valley dams. Note that Bridge
Street dam is not included in this analysis.
Task
Licensing
Repair Dams
Provide Fish Passage
Mitigate Warm Water Impact
Upgrade Flood Control Spillway
Operation and Maintenance
Total Estimated Cost
Total Estimated Revenue (over 30 years)
 Jackson (1,910 MWh)
 Whitewater (3,915 MWh)
 Pine Valley (3,151 MWh)
Estimated Cost
$ 600,000 – $ 750,000
$ 500,000 – $ 1,800,000
$ 5,500,000 – $ 7,000,000
$ 200,000 – $ 400,000
$ 1,020,000 – $ 4,300,000
$ 390,000 – $ 780,000
$ 8,260,000 – $ 15,030,000
$ 8,600,000
There is uncertainty in both costs and revenue estimates. The FERC licensing costs
were estimated after reviewing similar relicensing costs of existing hydroelectric
facilities in the state. The cost to repair the dams was based on the most recent
studies published by the US Army Corps of Engineers.
The cost to provide fish passage at the dams was based on the cost to install fish
passage at other dams in Michigan of comparable size. One objection to this cost
item being included is the view that natural resource agencies may not require fish
passage at the dams. While an argument can be made to block fish passage, the
final decision regarding fish passage would be made during the permit process after
a complete hearing.
The cost to mitigate the warm water discharge from the dams is based on an
independent assessment of the warm water impact and various methods to mitigate
the impact. It has been documented in several studies that there is a warm water
discharge from the ponds upstream of the dams that has a significant adverse
impact on the coldwater fish populations in the Green River. In order to obtain a
license to generate electricity, we anticipate that FERC will require that the warm
water impact be mitigated by collecting colder water from the bottom of the ponds
and discharging it into the Green River.
There is also a need to improve the emergency flood capacity of the Whitewater and
Pine Valley dams. Both dams are currently out of compliance and would need to be
improved in order to meet federal requirements for flood control.
The revenue estimate was based on the product of projected generation and
electricity prices. Calculations of hydropower potential are based on expected future
flow rates taken from the USGS Surface-Water Daily statistics for the Green River.
The generators were assumed to operate continuously with no down time for
maintenance. Hourly generation was projected forward for thirty years. If we
assumed that the equipment would not be replaced, the revenue analysis could be
extended further.
SUMMARY
The potential to restore hydroelectric power generation at Jackson, Whitewater and
Pine Valley dams was reviewed using information collected by our consulting team,
other engineering firms, and the US. Army Corps of Engineers. The results of the
study show that, while the potential exists for generating power at the dams, the cost
to license, repair and upgrade the dams in order to comply with state and federal
regulations may outweigh the revenue generated by selling electricity generated at
the dams. If the dams can be licensed without a requirement for providing fish
passage, then the revenue gap is smaller.
If you have any questions, please feel free to contact us to clarify issues we have
raised in this summary.
Sincerely,
Barbara Gosling, Ph. D.
Lead Engineer
Gosling & McClintock Environmental Consultants, Inc.