by Neil Carleton
Development in or along the Mississippi River has the potential to adversely affect the ecosystem. This includes the flora and fauna of the river water, shoreline, and river bed.
It’s easy to understand why many residents might have environmental concerns about Enerdu’s proposed powerhouse. These range from possible damage to the natural beauty of our shared treasure, to the potential degradation of the health of our sensitive river ecosystem.
The company is proposing to expand and redevelop its existing hydroelectric waterpower facility in town. This expansion would increase the generating station’s capacity from 300 kW to approximately 0.95 MW. The project, if approved, would include the:
- addition of a second generator in housing that would extend into the Mississippi River;
- excavation of a large portion of the riverbed to form a holding pond;
- installation of an expanding bladder-type dam at the upper falls.
The project, as reported in recent media notices, is subject to the Class Environmental Assessment (EA) for Waterpower Projects, and is categorized as a project associated with existing infrastructure. An Environmental Report (ER) has been prepared by or for Enerdu as required under the Class EA.
In advance of reading the ER report this week at the library, I made a list of things that could be at stake as a result of the construction, operation, and maintenance of the proposed Enerdu project. I hope the summary that follows in this short posting will be of use to others who may wish to review and comment on the Enerdu ER.
Provincially Significant Wetlands (PSW) or Areas of Natural and Scientific Interest (ANSI)
Following a review of natural heritage values and data, The Ontario Ministry of Natural Resources (MNR) has determined there are no PSW or ANSI within the proposed site area.
Fish Nursery Habitat
The Mississippi River within 300 m of the proposed site is a fish nursery habitat, as documented by the MNR, for Smallmouth Bass, Rock Bass, Bluegill, and Yellow Perch.
A review by the MNR, of the Natural Heritage Information Centre and internal records, has identified there is an on-site potential for:
- River Redhorse Moxostoma carinatum
Our local fish is of special concern provincially and nationally. It’s particularly
susceptible to siltation and turbidity which can result from urban development, such as river disturbance of the magnitude proposed by Enerdu.
- American Eel Anguilla rostrata
Fish sampling by MNR has confirmed their presence in Mississippi Lake. This endangered species, therefore, uses the Mississippi River through Almonte as a migratory corridor.
MNR has also determined there is a potential in proximity to the development area for:
- Eastern Musk Turtle Sternotherus odoratus
Among the smallest turtles in Ontario, this species is threatened provincially and nationally. Populations have declined as development has changed shorelines. One was in fact caught during the MNR 2011 tailrace survey at the Enerdu site.
- Flooded Jellyskin Leptogium rivulare
Home for this leaf-like lichen is at the base of trees growing around vernal ponds that fill with meltwater in spring, then dry up in summer. It’s a provincially and nationally threatened species.
Appleton Wetland Forest
It’s been a stable ecosystem for a long time, remaining healthy as long as the base of the trees and the top roots could dry out for a period during the growing season in summer and early fall.
Only two years after the installation of modified flashboards on the Almonte weir, a significant tree die-off was documented at this sensitive site upstream. Insect or disease damage, or any higher than normal river water flow over the years, has been ruled out as the cause. Discussion has centered on the drowning of the trees from higher water levels, in the summer and fall, as a result of the modified flash boards and the subsequent rise in river level.
Any rise in river level which might result from the Enerdu project could jeopardize the forest and any natural recovery of this ecosystem that may still be possible.
Changes to the Flow Regime
Any changes to the flow regime of the river that result from the construction, operation, and maintenance of this project have the potential to adversely affect the flora and fauna of the river water, shoreline, and river bed. This could include:
- changes to water levels and water flows of the river;
- elimination of a river environment and the creation of a backwater or lake environment above a new dam;
- permanent flooding of soils with subsequent mercury introduction and increased sediment loads;
- impacts to surface water quality and flow;
- impacts to base flows and groundwater levels.
Rights to the River Bed
Of significance to the project is Enerdu’s claim that the rights to the riverbed at the project site are held by the company. Following a preliminary review of title information, MNR believed in March 2011 that the bed of the Mississippi River was never granted and consequently remained Crown land. Further review of the issue continued in 2012 by MNR.
At question, perhaps, is whether action in the earlier years of last century to repatriate beds of rivers in Ontario back to the Crown is part of the title records for Enerdu’s properties. If the owner of the land at that time (Wylie Milling Company Ltd.) kept the bed of the Mississippi River in these parcels, did the subsequent owners, and does the present owner, retain any riverbed rights? What has title search and land survey information determined?
If any part of the proposed Enerdu project is to take place on riverbed that is Crown land, has this also been addressed in the ER?