Environmental Flow Negotiations for Proposed Waterpower Sites in Northeastern Ontario, 2005 – 2015
By: Rich Pyrce (MNRF Northeast Region, Engineering Unit) Environmental Flows:
The flows that the people of the Province of Ontario want to see downstream of a dam, or in a bypass reach, that will sustain the ecological, biological, and geomorphic integrity of a river, as well as any aesthetic or spiritual values.
Main Message:
Considering all aspects of waterpower development, a balance is needed between economic expectations and environmental flows. Environmental flows (in m3/s) are achieved through negotiation between Provincial & Federal Governments, Waterpower Proponent’s & Consultants, and various stakeholders.
Bypass Reach length can vary from 50 metres to 15 kilometres.
Occasionally, there is no bypass. Environmental flows are required directly below the dam. Legislative Authority
Ministry of Natural Resources & Forestry (MNRF): • PLA (Public Lands Act) • LRIA (Lakes & Rivers Improvement Act) • SAR (Species at Risk)
Ministry of Environment & Climate Change (MOECC): • EA (Environmental Assessment) • PTTW (Permission To Take Water) • Water Quality (mercury etc.)
Department of Fisheries & Oceans (DFO): • HADD (Harmful Alteration, Disruption or Destruction of Fish Habitat)
Little Abitibi River below New Post Diversion Dam The Waterpower Process: 1. Site Release (Site Release Package) 2. Applicant of Record status 3. Environmental Assessment (EA Statement of Completion) 4. Location Approval (under LRIA) 5. Plans & Specifications (under LRIA) 6. Construction Mattagami River at Island Falls 7. Water Management Plan / OMS Plan 8. Monitoring / DSR / Compliance
Below a dam or in a bypass reach Environmental Flows aim to protect: 1. Valued Ecosystem Components (VEC’s) (fish, habitat, invertebrates, …) 2. Social Economic Concerns (SEC’s) (aesthetic flows, downstream users, …) MNRF’s Northeast Region has:
• 1 Regional Office in South Porcupine (Timmins)
• 9 District Offices Natural flows in Northeastern Ontario: Water Survey of Canada gauges, with daily average flows (m3/s)
DA = 401 km2 DA = 1190 km2
DA = 6680 km2 DA = 8940 km2 Regulated Flows in Northeastern Ontario: Water Survey of Canada gauges, with daily average flows (m3/s)
DA = 1930 km2 DA = 3130 km2
Moose River above Moose River (04LG004)
DA = 5540 km2 DA = 60100 km2
Daily flow data does not have the resolution to capture the complexity of regulated discharges. Hourly flow data (rather than daily) is required. Magpie River: Natural Flow (m3 s-1) [1985]
Average daily flows
Magpie River: Regulated Flow (m3 s-1) [2006]
Hourly flows Environmental Flows (MNRF has considered and / or used):
• 7Q’s Low flow characterization (e.g. 7Q10, 7Q20).
• The Monthly Q80 The Q80 is seen as a conservative baseflow equivalent.
• The Q95 Q95 is cited in the scientific literature as a low flow or extreme low flow.
• Wetted Perimeter Preserve a specific percentage of the natural wetted perimeter.
• Demonstration Flow Assessment Bring all stakeholders together on site and release specific flows to see if a consensus can be reached.
• The BF75 Perform a baseflow separation and use the 75% percentile for the lowest median monthly baseflow value (BF50), for a specific period of record. Bypass Reach: Mississagi River at Aubrey Falls Magpie River below Steephill Falls G.S. Bypass Reach: Ivanhoe River at The Chutes Bypass Reach: Lizard Creek Bypass Reach: Bridal Veil Falls below Lake Kagawong Environmental Flows - Peter Sutherland Sr. G.S. on New Post Creek New Post Creek Site Map & Bypass Reach • Drainage basin = 3052 km2 (from 318 km2 due to an upstream diversion). • 28 MW of power produced. • Bypass reach is 5.5 km long. • WSC gauge 04ME005 has provided flow data since 2010.
• VEC’s include fish and spawning values below New Post Falls. • SEC’s include an old Hudson Bay Co. post, and aesthetic flows over New Post Falls. The Drainage Basins of New Post Creek (pre- and post-diversion). Leading Up To Environmental Flow Decisions:
• MNRF, OPG, and Consultant held a 2-3 day field tour to identify all environmental and social concerns.
• Consultant (C.Portt & Associates) did extensive sampling and modelling work below New Post Falls.
• Ontario Parks involvement (Sudbury office).
• Face to Face meetings with all stakeholders, numerous conference calls.
• Hydrology analysis based on current Water Survey of Canada gauge data, and historical data of flows provided by OPG.
• Extensive discussions between OPG & Coral Rapids Power & MNRF Cochrane District.
New Post Creek above New Post Falls The minimum continuous discharge rates through the concrete spillway in New Post Creek are as follows:
• October 1st to April 30th (7 months) = 2.00 m3/s • May 1st to June 15th (1.5 months) = 15.00 m3/s • June 16th to August 31st (2.5 months) = 7.50 m3/s • September 1st to September 30th(1 month) = 5.00 m3/s
• These flows would accommodate First Nations concerns (Taykwa Tagamou Nation), biology concerns, and aesthetic flow needs.
• The Water Survey of Canada gauge below the Dam Site provides MNRF with reliable flow information for compliance purposes.
• A Demonstration Flow exercise occurred in 2017 to examine the summer flow over New Post Falls for aesthetic purposes. Environmental Flows - Mattagami River below Mattagami Lake Dam
Bypass reach at Mattagami Lake Dam (no VEC’s or SEC’s identified) Mattagami Lake Dam – below tailrace (high fisheries value: walleye & whitefish) Mattagami River at Mattagami Lake Dam: Flow Demonstration (BOGSAR, Railsback and Kadvany, 2008)
• In September 2008, OPG released different low flows from the Mattagami Lake Dam, and the MNRF Timmins District Biologist and OPG Biology Consultant were both on hand to assess flow depth and flow velocities.
• The demonstration flows were 1.2 m3/s, 2.6 m3/s, 3.2 m3/s, and 4.6 m3/s.
• Both OPG and MNRF felt a flow of 1.2 m3/s was not sufficient.
• A flow approximating a Q95 was economically infeasible.
• The Proponent was happy with a flow of 2.5 m3/s; MNRF wanted 2.7 to 2.8 m3/s.
• At a Face to Face meeting an agreement was found – the minimum flow provided to the downstream reach would be 2.8 m3/s. Environmental Flows - Bypass Reach: Kapuskasing River at Big Beaver G.S. Bypass Reach, and Kapuskasing River at White Otter G.S. Bypass Reach. Kapuskasing River – Hydroméga Sites Kapuskasing River environmental flows were worked on from 2006 to 2008. • Initial environmental flow values proposed were 1 m3/s.
3 • MNR sought monthly Q80 values in bypass reaches of generally 10 – 20 m /s during the months of July, August, and September.
• (The Q80 flow is seen to be equivalent to a natural baseflow in a river, essentially that flow which can sustain the aquatic ecosystem integrity in a river channel.)
• Various discussions ensued, over many months. (Lots of meetings and conference calls, and flow data analysis).
MNR ADM Briefing Note (April 3rd, 2008): • “MNR ensures provisions for ecological flows and levels that will support the sustainability of the aquatic ecosystem for the perpetuation of fish, wildlife, and other natural resources.” • “MNR will forward all decisions to DFO where fish habitat is likely to be altered.” • “Principal environmental concerns are about instream flows for diversions (bypass reaches) at Big Beaver and White Otter: • i) effects on native fish communities, and • ii) provincially and globally significant dragonfly species, provincially rare vascular plant species. Bypass Reach
Environmental Flows through Big Beaver G.S. Bypass Reach (225 metres in length):
• Winter Season (Nov 1st to Apr 30th) = 2.5 m3/s • Summer Season (May 1st to Oct 31st) = 4.75 m3/s Kapuskasing River at Big Beaver Generating Station Environmental Flows in White Otter Falls G.S. Bypass Reach (1000 metres in length):
• Continuous Flow = 2.0 m3/s • Walleye Spawning Season = 30.0 m3/s (+ gradual ramp down) Kapuskasing River at White Otter Falls – Bypass Reach (looking downstream) Kapuskasing River at White Otter Falls – Bypass Reach Flow Control Dam Environmental Flows: Bypass Reach White River at Gitchi Animki Bezhig, and White River at Gitchi Animki Niizh. Gitchi Animki Bezhig
From MOECC’s Permission To Take Water (May 2016):
• “A continuous minimum flow of three (3) cubic metres per second (m3/s) shall be maintained for residual benthic habitat maintenance throughout the length of the bypassed natural channel reach.”
• The bypass channel wetted width at 3 m3/s will be monitored and compared to the wetted width at 12.7 3 m /s (corresponding to a Q95 flow). “Should the wetted perimeter at the continuous flow of 3 m3/s be measured at less than 50% of the wetted perimeter at 12.7 m3/s, then mitigation measures must be taken … methods will include the provision of necessary flows, bioengineering, and compensation measures as may be necessary.”
• “A continuous minimum of thirty (30) m3/s shall be passed through the bypass channel reach during the walleye spawning and incubation period, which is typically May 1 to June 14 … to prevent egg dewatering and desiccation.” Gitchi Animki Niizh
From MOECC’s Permission To Take Water (May 2016):
• “A continuous minimum flow of four (4) cubic metres per second (m3/s) shall be maintained for residual benthic habitat maintenance throughout the length of the bypassed natural channel reach.”
• “A continuous minimum of thirty (30) m3/s shall be passed through the bypass channel reach during walleye spawning and incubation period, which is typically May 1 to June 14 … to prevent egg dewatering and desiccation.” Questions ?
Kapuskasing River at Cedar Rapids
Acknowledgements: • Dave Barbour (MNRF Hearst District, Kapuskasing Field Office) • Brooke Campbell-Paterson (MOECC Thunder Bay Regional Office) • Chris Chenier (MNRF Cochrane District Office) • Shawn Fortin (MNRF Wawa District Office) • Ryan Stainton (MNRF Peterborough Regional Office)