Esox dam input deadline Friday

FORT FRANCES—The public first got a chance to see what options the Ministry of Natural Resources is proposing to deal with a deteriorating dam on the Manitou River (Esox Lake) during a pair of open houses in early September.
Now for the past three months, the MNR has been asking for people’s responses as to what they think will be the best choice to make, with the deadline for input being this Friday (Dec. 10).
“This is the second time around [the MNR has asked for input on the Esox Lake dam] and a lot of the same people are responding,” MNR district planner Rachel Hill noted Tuesday, though adding that many are giving additional input beyond checking a box on the standard reply form.
“Every day I get a few in,” she added. “I’m anticipating a lot more this week.”
Hill said she sent out about 130 packages to those who requested them at the pair of open houses—one in Fort Frances and the second at Barker Bay Lodge on the Lower Manitou—in early September.
So far, about 30 percent of those have been returned.
While the deadline is Friday, Hill acknowledged she’ll be accepting them for a short time after that date to ensure the MNR has as many responses as possible to consider when making any decisions.
Hill noted while decisions such as this can be difficult, with many factors to weigh, she was certain a choice would be made by next spring as to the fate of the Esox dam.
Once any such decision is made, those who provided input will be notified of it, and given 30 days to again provide input to the MNR, before the decision is finalized.
The MNR has outlined five alternatives as to what can be done with the dam, which is located north of Devils Cascade and affects water levels along the entire Manitou watershed stretching 60 miles to the northeast (including Esox, the Manitou Stretch, Lower Manitou, and Upper Manitou).
These options include:
•Do nothing (i.e., no work would be done to repair the dam and it would be left to break down naturally).
While this would mean no further maintenance costs, it still would cost the MNR an estimated $5,000 a year to monitor.
More importantly, it ultimately would be a liability issue as water levels eventually would revert to those as if the dam were decommissioned (just not in a controlled fashion) and have “unpredictable social and safety costs.”
•Rehabilitation
The dam would be repaired to address current safety and liability concerns, and would extend the life of the existing structure by an estimated 20 years.
This would involve major concrete repair, which requires de-watering of the working dam site through the installation of a temporary coffer dam that would divert the water flow during the time the work is being done.
This would cost $1,682,000—slightly less than reconstruction—but maintenance costs would increase in the long-term. Manual operation of the dam still would be required.
There would be no significant impacts to current lakefront property, recreational, navigational, and commercial users on the lake as the lake level would remain as it is now.
•Reconstruction (control structure and weir)
The existing dam would be replaced with a new structure that would have three stop log bays and a weir. This would involve a new dam location downstream from the existing one, and require de-watering of the working dam site during constriction.
The dam would have a higher discharge capability than the existing one.
This option would require less operational and maintenance requirements for roughly 40 years, but the proposed work would have a high initial cost ($1,683,000)—a cost the MNR estimated would have to paid again after those 40 years.
This alternative still would require manual operation of the dam, but the requirement would be less than that of the rehabilitation option.
There would be no significant impacts to current lakefront property, recreational, navigational, and commercial users on the lake, but a fish habitat inspection has determined there would be short-term habitat loss and that compensation would be required.
•Reconstruction (overflow weir)
This alternative would see construction of a new dam downstream from the existing one, with a 17m long overflow weir.
The height of the weir would be lower than typical summer water levels under existing dam operations, causing lake levels to lower across the entire system by 0.4 m.
This option would cost $1,380,000, but eliminate future dam operation and minimize maintenance requirements.
The lower levels would have some impact on navigation, lakefront access, and fish and wildlife habitat, but not to the extent of the decommissioning alternative.
Navigation would be reduced relative to existing conditions. Under normal conditions, channels would provide roughly 0.5 m or greater depth.
The weir would result in greater variation of depth relative to the normal level in comparison to the operated dam.
Currently, water levels, on average, fluctuate less than a foot throughout the open water season; this would increase with a weir.
There would be lakefront recession of roughly six metres in certain areas, which would require tourism operators and property owners to relocate and/or lengthen docks, and possibly relocate existing infrastructure.
But a weir would result in more natural flow patterns throughout the system and benefit fish and wildlife. The drop of 0.4 m would not result in any acute short- or long-term concerns for the natural environment.
•Decommissioning
After a complete assessment of environmental and social impacts, a strategy would be developed for complete removal of the existing dam.
This alternative would allow for restoration of natural water levels throughout the chain of lakes. Decommissioning could occur in stages over a period of 10-15 years, resulting in gradual reduction in water levels.
Water levels would drop by an estimated 1.2 m on the Manitou Stretch, as well as the Upper and Lower Manitou, and 2.9 m on Gussie Lake and Esox Lake.
There also would be, on average, a lakefront recession of 18 m, requiring tourism operators and other property owners to relocate and/or lengthen docks and, where applicable, relocate or retrofit existing infrastructure. Channels, namely Esox Narrows (east and west), Four Miles Narrows, and Birch Narrows, would become non-navigable after the dam’s removal (at least for the dry time of the year), and navigational hazards in other relatively shallow areas within the lakes would be expected.
And the lake system would be isolated into three sections for part of the year—Esox Lake and Gussie Lake; the Manitou Stretch and Lower Manitou Lake; and Upper Manitou Lake.
A review of alternative lake access points would have to be done.
Removal of the dam would not have any impact on fish migration, and no specially-protected species of fish or wildlife would be affected, said the MNR.
In the long-term, this option would benefit fish and wildlife by restoring natural flows. The animals’ communities that exist here have evolved over 10,000 years in that system, and only have in the last 50 years accommodated higher levels.
Therefore, it is assumed, said the MNR, that species would accommodate to the change in lake levels and benefit from the natural flow pattern that would result.
This option would cost significantly less money than the others ($190,000), and also would eliminate future dam operation and maintenance costs and requirements.
Hill had stressed back in September that from the MNR’s viewpoint on this project, “cost is not a deciding factor.”