Halton Region - Permit for activities to achieve an overall benefit to a species

Proponent

Halton Region
1151 Bronte Road
Oakville , ON
L6M 3L1
Canada

Location details

Site location

Sixteen Mile Creek between Dundas Street and Highway 407

To see the site location on a map, refer to the instrument proposal under ERO# 019-1811

Instrument decision

On June 11, 2021, the Minister issued an overall benefit permit to  Regional Municipality of Halton under s. 17(1) of the Endangered Species Act, 2007 (ESA), with respect to Mottled Duskywing and Silver Shiner, for the construction of a section of the William Halton Parkway project that crosses Sixteen Mile Creek in Oakville Ontario.

The permit will authorize Regional Municipality of Halton during the construction to impact Mottled Duskywing and Silver Shiner, which are species at risk, and their habitat.

Impacts to Mottled Duskywing and its habitat include removing 75 m² of New Jersey Tea plants (approximately 42 plants). New Jersey Tea is an important larval food plant for this species.

Adverse impacts to Silver Shiner and its habitat include:

• destroying 86m² of floodplain habitat for placement of piers
• damaging 180m² of the bank of Sixteen Mile Creek
• damaging 9056m² of vegetation for access road and work areas

The permit requires Regional Municipality of Halton to undertake measures that will:

• minimize adverse effects to Mottled Duskywing and Silver Shiner 
• achieve overall benefit to Mottled Duskywing and Silver Shiner within a reasonable time

Actions to minimize adverse effects to species

For Mottled Duskywing, the permit requires the Regional Municipality of Halton to:

• retain plants, specifically New Jersey Tea plants, outside the limit of grading during construction with vegetation protection fencing
• New Jersey Tea plants within construction area are to be transferred to safe locations prior to construction beginning
• carry out three years of effectiveness monitoring to monitor the effectiveness of the construction-related and specific design-related mitigation measures (e.g. survival of the transplanted New Jersey Tea, survival and growth of the vegetation re-planted in temporarily disturbed areas, and effectiveness of vegetation protection measure)
• align the temporary access road to minimize impacts to floodplain vegetation and in particular trees and rare plant species
• site the bridge and temporary crossing locations over stable, straight sections of Sixteen Mile Creek

For Silver Shiner, the permit requires Regional Municipality of Halton to:

• align the temporary access road to minimize impacts to floodplain vegetation and in particular trees and rare plant species
• site the bridge and temporary crossing locations over stable, straight sections of Sixteen Mile Creek
• remove temporary access road following construction and restore the road and work areas around the piers
• replant temporarily disturbed natural areas of the floodplain habitat with the same/similar native species that are present now, or species otherwise compatible with the existing site conditions and vegetation community
• restore temporary work area in the channel to re-instate the existing bed profile and associated edge habitat
• incorporate naturalized techniques into the bank and pier footing protection design
• install rigorous erosion and sediment controls including containment and dewatering measures, and ensuring rigorous inspection throughout construction
• minimize the extent of, and isolating, the in-water construction zone using a robust cofferdam system designed to minimize creek flow into the work area
• conducting the work within appropriate timing windows and employing fish rescue measures
• monitor planted vegetation for a minimum of three years, and addressing survival below the 80% target

Actions to achieve an overall benefit to species

The permit requires the Regional Municipality of Halton to achieve an overall benefit for the Mottled Duskywing within a reasonable time by:

• creating a minimum of 190m² of habitat with local New Jersey Tea from the impacted site, nursery stock grown from locally sourced seed and a compatible native seed mix
• locating the habitat in a more open canopy area contiguous with habitat to the north of the existing habitat
• restoring an area (minimum of 250 m² in size) of existing habitat along the valley rim on Town of Oakville Natural Heritage System lands that are currently experiencing successional impacts

The permit requires Regional Municipality of Halton to achieve an overall benefit for the Silver Shiner within a reasonable time by:

• planting and naturalizing approximately 5170 m²of the floodplain on the west side of the channel that is presently part of the actively used park
• erecting signs to identify the overall benefit areas as naturalization areas not to be mowed / disturbed
• placing signs at three controlled access points, the existing pedestrian bridge area, and the trail that will be left at the end of the existing park trail as viewing areas, to encourage use of these access points and protection of the adjacent natural areas
• repairing and stabilizing a 30-metre-long section of severely eroding channel bank located at the end of the park trail using a vegetated rock buttress.

Other information

The Regional Municipality of Halton considered other reasonable alternatives, including:

• not constructing a valley crossing or extension for the road from west across valley and east tableland
• several bridge designs ranging between a clear span bridge, and 3, 4, and 5 span bridge
• relocating road alignment to an alternate site and the associated valley crossing of Sixteen Mile Creek
• alternative access options for construction to avoid crossing the creek, including:
  • accessing site from both sides of valley
  • accessing from east valley slope only
  • accessing from west slope only
  • accessing through existing impacted area (Lyons’ Valley Park), which requires temporary water crossings

The best alternative was adopted, which includes building a three-span bridge, with construction access using temporary roads through the park and two temporary water crossings. Overall footprint of the bridge is minimized and bulk of the impacts regarding accessing are focused on already cleared or disturbed areas in the park, thereby reducing the need to disturb new areas within the species habitat.

Government response statement for Mottled Duskywing

The ministry has published a government response statement under section 12.1 of the ESA with respect to Mottled Duskywing. You can access this statement through the ministry’s website: https://www.ontario.ca/page/mottled-duskywing-government-response-statement.

The minister considered the following in reaching a decision regarding the permit:

• supporting partners to undertake activities to protect and recover Mottled Duskywings and their habitat including support provided through permits (including conditions)
• rehabilitating degraded Mottled Duskywing habitat
• transfer and establishment of closely associated larval food plants such as New Jersey Tea

A government response statement has not been published under subsection 12.1 of the ESA for Silver Shiner.