7b. Environmental Protection and Mitigation Measures – Examples from other MTO Projects

  • Highway 401 Widening from 6 to 12 lanes core/collector system from Highway 403/410 Interchange to East of the Credit River, City of Mississauga, Region of Peel.
  • Highway 400 Widening from 6 to 10 lanes from north of 19th Sideroad to north of South Canal Bridges, Township of King, York Region.
  • On-going MTO Environmental Mitigation/Compensation Efforts.

Highway 401 Widening from 6 to 12 lanes core/collector system from Highway 403/410 Interchange to East of the Credit River, City of Mississauga, Region of Peel.

Environmental Protection:

  • MTO worked with the City of Mississauga, Credit Valley Conservation, Ministry of Natural Resources and Forestry, and the Ministry of the Environment, Conservation and Parks to develop a restoration plan as part of the widening of Highway 401.
  • This included a total restoration/compensation area of approximately 3 ha within the Ministry’s Right of Way (ROW) as well as on City of Mississauga lands. Nearly 3,000 trees and 7,000 shrubs were included in the restoration plan.
  • Temporary perimeter fencing was also implemented to allow trees the opportunity to grow, while avoiding foraging by deer.

Species at Risk Avoidance/Protection

Before

Prior to construction, the existing six-lane highway crossed Fletcher’s Creek through a concrete bottom twin cell culvert, which did not include a wildlife passage.

After

A new clear span bridge structure was constructed over Fletcher’s Creek to provide wildlife passage as well as to allow for groundwater upwelling in the creek. Fletcher’s Creek is regulated habitat for Redside Dace, a minnow species protected under the Federal Species at Risk Act as well as the Provincial Endangered Species Act.

Retaining Wall

MTO constructed a retaining wall totaling 420 m in length, on the north side of Highway 401. The retaining wall was included in the design as a measure of avoiding the amount of vegetation removal within Jefferson Salamander regulated habitat, an amphibian species protected under the Endangered Species Act.

Highway 400 Widening from 6 to 10 lanes from north of 19th Sideroad to north of South Canal Bridges, Township of King, York Region.

Environmental Protection:

  • MTO obtained a Section 17(2)(c) Endangered Species Act Permit for Redside Dace.
  • Overall benefit activities included channel remediation, riparian habitat and in-stream habitat enhancement for tributaries of the West Holland River (over 22,000 square metres of enhancement).
  • Additional overall benefit activities included the design and construction of Stormwater Management Facilities with bottom draw outlet structure, cooling trench, and outlet channel to treat previously untreated road runoff. This also constituted as Overall Benefit to Redside Dace.

Enhancements and mitigation measures on several MTO projects to protect the travelling public and wildlife – including fencing, culverts and underpasses for small and large animals.

Nottawasaga Underpass (Highway 26)

Wildlife Fencing (Highway 404)

Barn Swallow Habitat Compensation

  • Since January 2012, Barn Swallow is uplisted to ‘threatened’ under the Endangered Species Act.
  • MTO adopts appropriate avoidance/mitigation measures as well as replace habitat under certain circumstances in accordance with the Act whenever construction of highways and related infrastructure displaces Barn Swallows from existing nesting sites.
  • Nest cups are installed in structures called Kiosks, or within existing MTO infrastructure where Barn Swallow colonies reside, including salt domes.
  • MTO also continues to explore/research features to enhance nesting at these Kiosks including cross beams, privacy walls, enhanced planting plans.

7. Environmental Protection and Mitigation Measures

Environmental Protection and Mitigation Measures

Environmental assessments and the development of mitigation measures is an iterative and collaborative process. The Ministry will undertake the environmental assessment in accordance with the Ministry Class Environmental Assessment for Transportation Facilities for a Group ‘A’ project. Protection and mitigation measures will be implemented where practical and in consideration of the evaluation criteria. The intent is to balance the technical and environmental constraints for the proposed design refinements and alternatives. The following outline the proposed protection and mitigation measures to be reviewed and evaluated through the consultation and engagement with regulatory agencies during the study for each environmental consideration. These are generally developed from and reflect the Ministry Class Environmental Assessment and the 2002 approved Environmental Assessment mitigations measures and commitments.

Terrestrial Ecosystem

(Species at Risk, Areas of Natural Significance and Importance, wetlands, woodlots, deer wintering areas)

Protection and Mitigation Strategies related to: Destruction of wildlife Habitat, Barrier effect on travel corridors and, Wildlife-Vehicle accidents.

Mitigation Measures
  • Protect through alignment modification
  • Minimize impact by following edges of habitat areas and or crossing habitat areas at narrowest location
  • Minimize impact on edge or any part of area using appropriate design measures
  • The Project Team’s Wildlife and Plant Specialists will determine the potential permanent and temporary impacts of the various highway design alternatives through the terrestrial ecosystem assessment.
  • By using available openings skirting the large woodland blocks in the Holland River flood plain and using disturbed
    • edge location, habitat fragmentation in that area is minimized.
  • Protect corridors to provide wildlife access across ROW using appropriate design measures (e.g. culverts, etc.)
  • Restrict clearing of trees immediately adjacent to or within significant breeding areas to non-critical periods; and
    • monitor wildlife movement patterns and potential of conflict.
    • Mitigate using appropriate signage to increase driver awareness

To minimize road kills, measures will include a wide, grassed, open, median, fencing of the right-of-way, provision of good visibility for drivers, and the consideration of cautionary wildlife crossing signage.

Terrestrial Ecosystem

(Species at Risk, Areas of Natural Significance and Importance, wetlands, woodlots, deer wintering areas)

Protection and Mitigation Strategies related to: Severance of/encroachment on identified upland ecosystems; and Severance of/encroachment on identified aquatic/wetland ecosystems.

Mitigation Measures
  • Minimize intrusion by use of design measures (i.e. horizontal/vertical alignments)
  • Mitigate with plantings and/or other design measures to maximize usage of properties within the proposed right-of-way
  • Ecosystem studies and impact assessments to be conducted in accordance with the Environmental Reference for Highway Design ERD (2013)
  • Minimize intrusion by use of design measures (i.e. alignments, design of structures)
  • Minimize impacts through the use of surface water monitoring and mitigation plans
  • Utilizing timing window restrictions for applicable construction
  • Utilizing sediment erosion control measures
  • Consultation with Indigenous communities

Terrestrial Ecosystem

(Species at Risk, Areas of Natural Significance and Importance, wetlands, woodlots, deer wintering areas)

Protection and Mitigation Strategies related to: Effects on ANSI’s, ESA’s, Provincially significant Wetlands, Provincially rare species; Effects on cultural/heritage, social/economic landscape features; Effects on woodlands resources; and, Effects on traffic safety.

Mitigation Measures
  • Protect through horizontal/vertical alignments, grading and structural design that would avoid incursion
  • Utilize landscape planting to provide environmental buffer, erosion control, filter strips for water quality, fish habitat compensation, etc.
  • Obtaining permits through the MECP under the Endangered Species Act (ESA) where applicable, which may include mitigation and or monitoring conditions, and consultation requirements.
  • Timing constraints to restrict construction activities immediately adjacent to or within watercourses to low flow months and that avoid sensitive spawning periods;
  • Minimize impact through design alterations to permit maximum retention of existing features
  • Utilize landscape planting plan to provide mitigation, screening and enhancement
  • Utilizing findings and information from the Cultural Heritage Resource Assessment report.
  • Minimize impacts through design alterations to account for the maximum preservation of existing resources
  • Utilize landscape planting plan to mitigate impact resulting from tree removal
  • Where appropriate: edge management plans for areas of new disturbance to protect remaining trees and re-establish edge;
  • Where appropriate: salvage of existing native vegetation, seed, and topsoil for re-establishment in identified areas of significant disturbance;
  • Minimize impacts design alterations to allow for minimal impact on existing vegetation and meet safety requirements
  • Utilize landscape planting plan to enhance traffic safety e.g. tangent screening, headlight screening, snowdrift control etc.
  • Utilize a traffic management plan to maintain safe operations on existing roadways and pedestrian facilities with the study area and minimize traffic impacts during construction and staging of the highway.
  • All at-grade intersections at the interchange ramp terminals will be signal controlled if justified according to the provisions of the Ontario Manual of Uniform Traffic Control Devices.

Terrestrial Ecosystem

(Species at Risk, Areas of Natural Significance and Importance, wetlands, woodlots, deer wintering areas), Land Use and Community Effects

Protection and Mitigation Strategies related to: Severance of Greenway or Linkage

Mitigation Measures
  • Design structure to span area
  • Establish alternative greenway or linkage
  • Mitigative efforts will be focused on the restoration of natural vegetation disturbed by construction-related activities, thereby ensuring the continuity of the natural vegetation within the central portion of the study area.

Terrestrial Ecosystem

(Species at Risk, Areas of Natural Significance and Importance, wetlands, woodlots, deer wintering areas) & Agricultural Lands

Protection and Mitigation Strategies related to: Loss of soils excess soils.

Mitigation Measures
  • Minimize impacts and minimize grades using appropriate design measures
  • Erosion and Sediment Control measures and those outlined for Agriculture
  • Management of access soils will be completed in accordance with the MECP Onsite and Excess Soils Management Guidelines.
  • Management of Excess Soils to be completed under the supervision of a Qualified Person as prescribed.

Terrestrial Ecosystem

Landscaping & Air Quality

Protection and Mitigation Strategies related to: Noise, dust, spray, air quality.

Mitigation Measures
  • Control through minimum distance separation (i.e. 500 m) buffer from Hwy
  • Design landscape buffer

Fisheries and Aquatic Habitat

(Species at Risk, Specialized Habitat) and fluvial geomorphology

Protection and Mitigation Strategies related to: Direct Loss of Aquatic Habitat; Changes to water quality and quantity; and, Inhibit fish passage.

Mitigation Measures
  • Avoid loss of critical fish habitat through alternative culvert/structure types and designs
  • Minimize all other in-stream and floodplain habitat loss, through alternative culvert/structure types and designs
  • Restore disturbed vegetation and aquatic habitat features (e.g. substrate)
  • Minimize stream relocations and channelization in such a manner that habitat features are maintained or enhanced
  • Minimize tree removals adjacent to streams
  • Stabilize existing unstable banks and reaches to compensate for lost or altered habitat
  • Enhance existing in-stream and floodplain habitat to compensate for lost or altered habitat
  • Enhance stream flow characteristics (e.g. flow deflectors) to compensate for lost or altered habitat
  • Remove existing barriers to fish passage to compensate for lost or altered habitat
  • Storm water control through Storm water BMPs (e.g. grassed swales, extended detention ponds)
  • Minimize water removal from low volume streams subject to water taking regulations
  • Design of culverts/stormwater facilities to account for groundwater upwelling areas
  • Where appropriate, design bridges and culverts that maintain the existing channel form or include a low flow
  • Ensure culvert/structure design and placement permits fish passage or does not further impair fish passage
  • The proposed long-span bridge across the Holland River branches will retain wildlife movement opportunities along the riverbanks

Groundwater

(Highly Vulnerable Aquifers, Significant Groundwater Recharge Areas, Wellhead Protection Areas, water wells)

Protection and Mitigation Strategies related to: Increased pollutants to groundwater recharge areas; Increased/Decreased runoff (water quantity) to groundwater recharge areas; Potential impacts to well water levels and quality due to the proposed design.

Mitigation Measures
  • Carry out Stormwater Management Plan (Study) to minimize water quality impacts to groundwater recharge areas
  • Incorporate recommended stormwater management practices into the design package
  • Avoid Infiltration measures
  • Tiling of soil in non-vegetated areas prior to restoration to re-establish infiltration along access roads, storage areas, or other well travelled areas where soil compaction has occurred
  • Backfilling of excavations that intercept existing groundwater flow with porous granular material to maintain existing groundwater linkage particularly at river crossings;
  • Carry out Stormwater Management Study and Incorporate recommendation in design package
  • Reduce depth of cuts in areas of shallow groundwater
  • Bridge runoff should be discharged to stormwater management facilities (preferably a pond or swale) prior to discharge to watercourses where this reasonably can be achieved and will not cause unacceptable environmental, highway design, safety, or operational problems.
  • The drainage plan will minimize the ponding of salt-laden runoff, and decrease impacts on sensitive aquatic habitat for breeding amphibians and other species.
  • Identify wells of high potential for impacts due to the proposed design
  • Consider pre-construction monitoring (sampling) of wells

Surface Water

(Drainage, fluvial geomorphology, watercourses/waterbodies)

Protection and Mitigation Strategies related to: Potential increase in upstream/downstream flood levels and erosion at watercourses; Potential increase of pollutants to receiving watercourses (increase imperviousness) – water quality; Potential increase in surface erosion to receiving watercourses.

Mitigation Measures
  • Carry out an analysis and design of watercourse crossings (culverts and bridges) in accordance with Ministry Standards, Policies and Directives to minimize flood risk and erosion
  • Develop stormwater management plan (Stormwater management study) to identify water quantity facilities to control peak flow (runoff). Incorporate recommendations (facilities) into design package
  • Incorporate erosion protection measures into the design package
  • Carry out a stormwater management study to identify stormwater management practices (SWMPs) to be incorporated into the design package
  • Develop erosion control plan - incorporate SPs, NSSPs and drawings into contract package
  • Conduct and Erosion and Sediment Control Risk Assessment (ESCORA) in accordance with the MTO Environmental Guide for Erosion and sediment Control.

Air Quality

(Greenhouse gases, traffic emissions) and Human Health

Protection and Mitigation Strategies related to: Potential effect of long-term exposure, if exceedances of current air quality standards related to: health impacts; plant and crop damage; property deterioration/cleanliness.

Mitigation Measures
  • Determine need to model impact on air quality of highway improvements, based on criteria for modelling developed by MTO for traffic, volume, number of lanes and atmospheric conditions to determine the need for mitigation measures
  • Minimize impact through appropriate design measures (depressed grade for air quality problem areas)
  • Improve traffic flow to reduce “stop and go” driving
  • Air quality assessment conducted for the preferred route.

Erosion and Sediment Control, Surface Water

(Drainage, fluvial geomorphology, watercourses/waterbodies), Fish and Fish Habitat and Landscaping

Protection and Mitigation Strategies related to: Erosion and sedimentation; and, Erosion and sedimentation in watercourses.

Mitigation Measures
  • Minimize erosion by slope modification (flattening, benching, serration)
  • Minimize erosion by use of retaining walls
  • Utilize lease erodible fill material in highly sensitive locations
  • Implement Landscape planting plan
  • Control of runoff
  • Mitigation will include contract specifications that require the preparation of sedimentation and erosion control plans, which provide the details of implementation, monitoring, and commitment to undertake modifications where necessary during construction to maintain effectiveness;

Aesthetics, Landscaping, Community Effects and Human Health

Protection and Mitigation Strategies related to: Effects on visual landscape and scenic resources available to motorists (views from the road); Effects on adjacent dwellers sensitive to views of the facility; Effects on passive recreation potential of scenic/natural adjacent sites e.g. river valley systems.

Mitigation Measures
  • Establish design refinements that would best capture scenic potential
  • Utilize grading design to minimize removal of aesthetic landscape features
  • Ensure structural/lighting design is consistent with aesthetic conditions of site
  • Incorporation discussion on aesthetics into the consultation process.
  • The two river crossing structures will be designed in an aesthetically pleasing manner using clean, simple, low-profile lines, visual appeal to motorists and to those who may see the bridge from below will be a significant factor in selecting and detailing the bridge design.
  • Design horizontal/vertical alignments that would least expose sensitive viewer groups to highway
  • Design grading to permit maximum retention of existing vegetative/visual buffer
  • Avoid visually intrusive structure/retaining walls designs
  • Provide visual screening and aesthetic enhancement through landscape design with earthwork and plantings
  • Design horizontal/vertical alignments that would require lease disruption to scenic/natural sites e.g. river crossings
  • Ensures structural design is visually consistent to the aesthetic conditions of site and would cause lease disruption to site
  • Include landscape treatments to mitigate visual impact e.g. structures over scenic/natural valley sites

Noise

(Construction noise, traffic noise) and Human Health

Protection and Mitigation Strategies related to: Increased Highway noise levels.

Mitigation Measures
  • Minimize impacts through adjustments to highway gradient and/or vertical alignment
  • Evaluate mitigation in accordance with the MTO environmental guide for noise

Community Effects

(Agricultural, industrial, residential, commercial)

Protection and Mitigation Strategies related to: Loss of homes; Impacts to property; Loss of recreation/community facilities; Permanently removing existing driveway/business access.

Mitigation Measures
  • Mitigate impacts by:
    • acquiring property at fair market value
    • considering advance purchase
    • providing appropriate notice period (per lease agreements) if land is in public ownership
  • Minimize direct impacts to property by following lot/concession/field lines or existing right-of-way
  • Compensate for ‘injurious affection’: where land is taken MTO may compensate landowners for damages resulting from both construction and use of the highway, where no land is taken, MTO is only responsible for damages resulting from construction of the highway
  • During preliminary design, the Ministry will undertake a review of the property-focused impacts of the preferred preliminary design.
  • Mitigate impacts by acquiring property at fair market value
  • Preliminary design completed to minimize loss of recreational and community facilities.
  • Provide new/alternate access
  • Providing communications with property owners in advance of impacts to property.

Community Effects

(Agricultural, industrial, residential, commercial)

Protection and Mitigation Strategies related to: Disrupting character of area; Permanently closing pedestrian/bicycle accesses; Permanently closing driveway/business accesses; Potential impacts on public transit routes; Potential impacts on emergency response routes; Disruption of community infrastructure/services.

Mitigation Measures
  • Preserve existing amenities as much as possible
  • Retain and/or plant vegetative buffer areas
  • Grade site to pleasing lines, utilize berms
  • Design and site structures to blend with adjacent areas
  • Provide new / alternative access and routes
  • Consult with transit authorities to minimize conflicts/enhance opportunities
  • Consult with response agencies during design to minimize disruption, coordinate activities
  • Consult with utilities (electricity/water/sewer/gas/telephone/cable) during design to minimize disruption, coordinate activities

Community Effects

(Agricultural, industrial, residential, commercial)

Protection and Mitigation Strategies related to: Loss of businesses; Impacts to property; Permanently removing existing entrance/exit.

Mitigation Measures

Mitigate impacts by:

    • acquiring property at fair market value
    • considering advance purchase
  • Minimize direct impacts to property by following lot/concession field lines or existing right-of-way
  • Compensate for ‘injurious affection’: where land is taken, MTO may compensate landowners for damages resulting from both construction and use of the highway, where no land is taken, MTO is only responsible for damages resulting from construction of the highway
  • Mitigate impacts by:
  • acquiring property at fair market value
  • considering advance purchase
  • Minimize direct impacts to property by following lot/concession field lines or existing right-of-way
  • Compensate for ‘injurious affection’: where land is taken, MTO may compensate landowners for damages resulting from both construction and use of the highway, where no land is taken, MTO is only responsible for damages resulting from construction of the highway

Agricultural Lands

Protection and Mitigation Strategies related to: Loss of specialty crop lands and class 1,2,3 agricultural soils, permanently removing existing access, Impacts to property.

Mitigation Measures
  • Minimize impacts through adjustments to highway gradient and/or vertical alignment
  • Evaluate mitigation in accordance with the MTO environmental guide for noise

Land Use

(Designated Areas, Policy Areas)

Protection and Mitigation Strategies related to: Reduced ability to proceed with approved private developments; and, Higher intensity of land use than previously existed.

Mitigation Measures
  • Consider alternative alignments, cross-sections to minimize impacts on approved developments
  • Corridor control to ensure that entrances and exits on the highway remain at a safe level

Contamination

(Areas of medium or high potential contamination)

Protection and Mitigation Strategies related to: Encroachment upon waste disposal sites and contaminated property; Contamination of ground water and surface waters; Contamination of R-O-W from waste disposal sites or contaminated properties; Release of asbestos or lead into the air/environment; and, Generation of excess concrete; asphalt or natural wood from the Right-of-Way.

Mitigation Measures
  • Conduct field investigations as necessary to determine absence or presence of contamination and quantify and characterize contamination, e.g. Phase I & II Environmental Site Assessment & remediate as necessary
  • Minimize encroachment through design measures (e.g. alignment shift)
  • Conduct field investigations as necessary to determine absence or presence of contamination and quantify and characterize contamination, e.g. Phase I & II Environmental Site Assessment
  • Design drainage measures to prevent landfill leachate from mixing with Highway drainage
  • Design measure to prevent waste material from impacting/entering the R-O-W
  • Design measures to prevent construction activities from impacting site, or contacting contaminated areas
  • For combustible gas – design measures to prevent explosive build up in confined spaces on R-O-W
  • Any waste material or contaminated soils encountered will be managed in accordance with the requirements of applicable legislation, such as the Environmental Protection Act, and with applicable guidelines such as the MECP Guidelines for Use at Contaminated Sites in Ontario.
  • Measures for surface water and groundwater impacts related to contamination
  • Incorporate/re-use excess materials into the design where possible and applicable
  • Proper handling & disposal of asbestos/lead waste
  • Controlled removal of asbestos/lead – containing materials
  • Testing of suspected asbestos/lead – containing substances as warranted
  •  

Archaeological Resources and Built Heritage

(Built Heritage Resources, Cultural Heritage Landscapes)

Protection and Mitigation Strategies related to: Loss of archaeological resources; Loss of heritage structures/resources; Deterioration of sites or structures having archaeological or heritage value as a result of environmental changes.

Mitigation Measures
  • Pre-construction archeological survey and salvage in consultation with heritage agencies
  • Consultation with Indigenous communities on historical archeological significance
  • Archaeological assessments
  • Once the specific nature and extent of archaeological resources impacted by the highway are identified, appropriate mitigation measures will be developed in accordance with the MTO/MHSTCI guidelines.
  • Documentation and restoration or removal of resources
  • Decrease harmful environmental condition changes such as vibration, altered water table, etc.
  • Involvement of Indigenous community monitors during archaeological investigations

Overview of Environmental Assessment Studies

The following environmental discipline studies will be carried out during the current Preliminary Design and Class EA Study:

  • Agricultural Impact Assessment
  • Air Quality Impact Assessment
  • Cultural Heritage Assessment
  • Erosion and Sediment Control Risk Assessment
  • Groundwater Impact Assessment
  • Land Use and Property Impact Assessment
  • Noise and Vibration Impact Assessment
  • Preliminary Landscape Composition Plan
  • Snowdrift Assessment
  • Waste and Excess Materials Management Plan

Studies initiated in 2020:

  • Archaeological Assessment (Stages 2, 3 and 4)
  • Drainage and Hydrology
  • Fish and Fish Habitat Existing Conditions and Impact Assessment
  • Fluvial Geomorphology
  • Terrestrial Ecosystems Existing Conditions and Impact Assessment

A Transportation Environmental Study Report (TESR)

  • A TESR will be prepared in accordance with the MTO Class EA to document the design and environmental process, as well as potential environmental impacts and mitigations.
  • The TESR will be made available for public and agency review for a period of 30 days at the end of this study.
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