CARP CREEK EMBANKMENT RESTORATION Conservation Ontario Class Environmental Assessment Public Information Centre March 8, 2018 Welcome!

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1 CARP CREEK EMBANKMENT RESTORATION Conservation Ontario Class Environmental Assessment Public Information Centre March 8, 2018 Welcome!

2 Conservation Ontario Class Environmental Assessment Approach The Carp Creek Embankment Restoration project is following the process outlined in: Conservation Ontario's Class Environmental Assessment for Remedial Flood and Erosion Control Projects. The process provides a project planning and design framework for proponents (conservation We are here authorities like Mississippi Valley Conservation Authority) to ensure they meet the requirements of the Provincial Environmental Assessment Act. As part of the process, consultation is required with all stakeholders including the public and agency partners at all stages.

3 Study Area The Carp Creek Embankment Restoration study area is located along the Carp Creek within Glen Cairn community, between Terry Fox Drive and Eagleson Road. The portion of creek under investigation runs perpendicular between Castlefrank Road, and Old Colony Road, and is adjacent to the Hope Cloutier Park and A.Y. Jackson High School, within the City of Ottawa. This Class EA is solely to remediate the severe erosion occurring within the study area limits and will not address and/or deal with recent flooding issues along the Carp Creek/River.

4 Project Overview and Background Mississippi Valley Conservation Authority (MVCA) identified concerns to the City of Ottawa pertaining to embankment erosion upstream of the pedestrian bridge crossing just downstream of Old Colony Road. Investigations by City of Ottawa staff and reports from community and residents did confirm that there is one area of potential concern upstream of the pedestrian bridge crossing which flows through a 90 degree bend in the tributary and the outside bank is showing evidence of more rapid erosion then other locations within the study area.

5 Problem Statement/ Purpose of the Undertaking The Carp Creek embankment has become unstable due to various flooding events and severe erosion. The severe erosion is primarily along the southeast embankment. If erosion of the embankment is to continue, it will deposit high levels of sediment into the watercourse, as well as extend into the green space along the Carp Creek which is immediately adjacent to residential dwellings. The erosion of the embankment will not only impact the natural environment, but it will also create a public health and safety concern and risk to privately-owned properties.

6 Project Objective It is Mississippi Valley Conservation Authority s initiative in partnership with the City of Ottawa to identify a preferred alternative solution that will: Stabilize the Carp Creek embankment within the study area and prevent any further erosion, and To restore the embankment back to a natural and functional feature of the watercourse. Issues Related to Erosion The eroded area is located at a sharp creek meander which is exposed to excessive erosive forces at the time of high flood level and high velocity ( m/s). The existing bank is failing due to the creek being out of alignment which is causing toe erosion and mass washout of the existing slopes. The southeast embankment is relatively steep and remains susceptible to high discharge events that will eventually lead to further failure, and The sites geotechnical stratigraphy consists of clay material topping till with a low bearing capacity.

7 Baseline Environmental Inventory Study Area Description Carp Creek is part of the headwater area of the Carp River watershed. The creek is located within a forested valley and surrounded by the Glen Cairn community, A.Y. Jackson Secondary School, Hope Cloutier Park, and the Frank MacDonald Ball Park. The eroded area is located at a sharp creek meander along the south embankment which has produced approximately a 3.3 m vertical cut through the existing topsoil and clay. The average bankfull widths and depths through this reach are 5.25 m and 0.57 m, respectively. This reach of the Carp Creek is found in clay plains, leading to poor soil infiltration, and therefore is prone to flooding. The topography is generally flat. Natural Science Carp Creek is known to have a warm water thermal regime. Potential Species-at-Risk (SAR) within the general vicinity of the study area, as well as their status and habitat protection are stated in below table. Potential impacts to the surrounding natural environment will be considered during the evaluation of alternative solutions, and potential mitigation measures will be identified. Species at Risk Common Name Scientific Name Provincial Status Federal Status Blanding s Turtle Emydoidea blandingii Threatened Threatened Eastern Musk Turtle Sternotherus odoratus Special Concern Threatened Common Snapping Turtle Chelydra serpentina Special Concern Special Concern Canada Warbler Cardellina canadensis Threatened Threatened Eastern Wood-pewee Contopus virens No Status Special Concern Red-headed Woodpecker Melanerpes erythrocephalus Threatened Threatened

8 Preliminary Alternative Solutions The alternative solutions identified for the Carp Creek Embankment Restoration are as follows: Alternative 1: Do Nothing - The Conservation Ontario Class EA process requires the evaluation of a Do Nothing alternative solution. Alternative 2: Soldier Piles and Wood Lagging - Soldier piles are typically steel beams, which are driven into the bed of the streambank, with wood lagging between the beams. Soil is then backfilled between the soldier piles and wood lagging wall to the point of erosion. Alternative 3: Mechanically Stabilized Earth would consist of backfilling the eroded area with soil/earth and reinforcing the earth with a retaining wall structure made up of a tensile material, such as a geo-synthetic material, which increases the strength of the soil.

9 Preliminary Alternative Solutions (continued) Alternative 4: Partial Channel Realignment with Live Bank/Bio-Engineering Treatment - a partial realignment of the channel to the north within the existing valley and stabilize the eroded embankment using a live bank/bio-engineering treatment. Live bank/bio-engineered treatments could consist of live crib wall, coir fibre logs, planting/rip-rap combinations, live stakes, wattle fence, etc. Alternative 5: Partial Channel Realignment with hard bank treatment - a partial realignment of the channel to the north within the existing valley and stabilize the eroded embankment using a hard surface treatments such as stacked/terraced stone revetment, gabion basket, rip-rap revetment, etc.

10 Preliminary Alternative Solutions (continued) Alternative 6: Full Channel Realignment full adjustment of the creek location and cross-section to redirect the flow away from the point of erosion. This provides an opportunity to design a system appropriate for existing flow regimes while moving the watercourse away from erosion-prone areas and residential dwellings, and has the potential to improve aquatic habitat conditions.

11 Screening Criteria Alternatives have been evaluated considering four environmental categories and various evaluation criteria specifically relevant to the study area, objectives and stakeholders: Screening Criteria Potential Effects Function Environment Effectiveness of Erosion Mitigation Embankment Stabilization Construction Feasibility Maintenance Does it effectively reduce/eliminate erosion, provides future protection and doesn t transfer erosion problem downstream? Does the proposed alternative provide slope stabilization? Is the erosion mitigation measure easy to construct? Is the erosion mitigation measure easy to maintain? Natural Environment Fish/Aquatic Habitat Impacts Terrestrial Habitat Impacts Species-at-Risk Impacts Aesthetic and Landscaping Geomorphology Fish/Aquatic Habitat Impacts during Construction and Operation? Are there potential impacts to the existing fish/aquatic habitat and/or potential to provide for opportunities to protect or create fish/aquatic habitat are preferred? Terrestrial Impacts during Construction and Operation? Are there potential impacts to the existing terrestrial habitat and/or potential to provide for opportunities to protect or create habitat? Does alternative impact species of interest/concern? Is the proposal alternative aesthetic pleasing and tie into the existing landscape? Does the proposed alternative impact the flow regime of the creek? Socio-Economic and Cultural Environment Public Safety Surrounding Land use and Recreational Impacts Affordability Sustainability Does alternative impact public safety during construction and/or day-to-day use following construction? Does it rectify a safety concern? Does it impact local land use and recreational activities? Disturbances due to construction noise and dust? Are there significant capital costs associated with this alternative? Are there significant maintenance costs associated with this alternative?

12 Evaluation of Alternative Solutions Preliminary Screening A long list of Alternative Solutions were evaluated for suitability based on functionality, natural environment, and socio-economic environment advantages and disadvantages. Alternative Solutions that were unable to meet the Problem/Opportunity Statement and the screening criteria were not carried forward to the detail evaluation. Long List of Alternatives Alternative 1: Do Nothing Alternative 2: Solider Piles and Wood Lagging Alternative 3: Mechanically Stabilized Earth Alternative 4: Partial Realignment with Live Bank/Bio-Engineering Treatment Short List of Alternatives Alternative 4: Partial Realignment with Live Bank/Bio-Engineering Treatment Alternative 6: Full Realignment Alternative 5: Partial Realignment with Hard Bank Treatment Alternative 6: Full Realignment

13 Criterion Significance Effects/Consideration Function Environment High High Moderate Moderate Effectiveness of Erosion Mitigation Embankment Stabilization Construction Feasibility Maintenance Overall Evaluation of Function Environment Moderate Fish/Aquatic Habitat Preliminary Evaluation of Short List of Alternative Solutions Alternative 4: Partial Creek Realignment with Live Bank/Bio-Engineered Treatment 4A Live Crib Wall 4B Planting/Rip-Rap 4C Brush Mattress 4D Coir Fibre Logs Highly effective on outside bends of stream where higher velocities are present. Crib walls provide both embankment and toe protection. Vegetation can also provide fish habitat. Highly effective - this alternative would stabilize the existing embankment within study area and be able to withstand higher flood levels and velocities. Once the live cuttings root and become established, the subsequent vegetation gradually takes over the structural functions of the wood members. Moderate disturbance typically requires larger machinery during construction for re-grading purposes and placement of logs. Low wall should vegetate and eventually become part of the natural environment. Yearly inspections are recommended. Moderate within the portion of the realigned creek, there will be opportunities to improve fish/aquatic habitat in new channel. There will be short-term impact during construction Highly effective - protection for both the toe and upper embankment. Choose native plants which promote biodiversity and are suitable to the shoreline environment. Woody shrubs possess complex root structures that work to stabilize soils. Highly effective - this alternative would stabilize the existing embankment within study area and be able to withstand higher flood levels and velocities. Rip-rap can be designed for high velocity flow conditions. Moderate disturbance typically requires larger machinery during construction for re-grading purposes and placement of logs. Low vegetate should establish along the embankments and eventually become part of the natural environment. Has a long life and seldom needs replacement, low maintenance. Moderate within the portion of the realigned creek, there will be opportunities to improve fish/aquatic habitat in new channel. There will be short-term impact during construction Low effectiveness Brush mattresses provide immediate protection to the exposed bank. However, are more effective on upper slopes of an embankment but less effective on lower banks due to washout during high flood events and higher velocities. Moderately effective - this alternative would stabilize the existing embankment within study area. However, this alternative is not as effective at protecting the toe of slope and therefore stability issues may reoccur overtime. Moderate labour Intensive to install. Moderate - seeding and mulching of the slope should take place immediately after installation. Watering may be necessary in dry conditions. Moderate within the portion of the realigned creek, there will be opportunities to improve fish/aquatic habitat in new channel. There will be short-term impact during construction Low effectiveness - bundles are flexible and capable of molding to the shoreline, however, are not suitable for high flow or shear stress areas. Moderately effective - this alternative would stabilize the existing embankment within study area. However, this alternative is not as effective at protecting the toe of slope and therefore stability issues may reoccur overtime. Moderate labour Intensive to install. Moderate need frequent inspection and maintenance to ensure logs remain in place Moderate within the portion of the realigned creek, there will be opportunities to improve fish/aquatic habitat in new channel. There will be short-term impact during construction Alternative 2: Full Creek Realignment Highly effective - new channel would be designed to be stable within the existing flow regime. Highly effective - new channel would be designed to be stable within the existing flow regime. Higher level of difficulty to construct due to full realignment. Realignment would require additional land which would mean the loss of existing recreational facility. Largest construction area/duration required. Low - natural channel would be designed to require minimal maintenance. Moderate opportunity to improve fish/aquatic habitat in new channel. However an extensive realignment would be required through the study area and adjacent lands, including areas that are currently not exhibiting any problems. Biological/ Physical/ Natural Environment Moderate High Low Terrestrial Habitat (wildlife, habitat, and vegetation) Species-at-Risk Aesthetic and Landscaping Moderate short-term impacts associated with construction activities such as minor loss of mature trees and short-term impacts to riparian species. Post-construction site restoration would ensure no long-term adverse effects or changes to terrestrial habitat affected. If terrestrial habitat is to be removed during construction, mitigation measures are to be implemented to protect SAR. Choose native plants which promote biodiversity and are suitable to the shoreline environment. Wall will vegetate overtime and eventually become part of the natural environment. Moderate short-term impacts associated with construction activities such as minor loss of mature trees and short-term impacts to riparian species. Post-construction site restoration would ensure no long-term adverse effects or changes to terrestrial habitat affected. If terrestrial habitat is to be removed during construction, mitigation measures are to be implemented to protect SAR. Choose native plants which promote biodiversity and are suitable to the shoreline environment. Wall will vegetate overtime and eventually become part of the natural environment. Moderate short-term impacts associated with construction activities such as minor loss of mature trees and short-term impacts to riparian species. Post-construction site restoration would ensure no long-term adverse effects or changes to terrestrial habitat affected. If terrestrial habitat is to be removed during construction, mitigation measures are to be implemented to protect SAR. Choose native plants which promote biodiversity and are suitable to the shoreline environment which eventually become part of the natural environment. Moderate short-term impacts associated with construction activities such as minor loss of mature trees and short-term impacts to riparian species. Post-construction site restoration would ensure no long-term adverse effects or changes to terrestrial habitat affected. If terrestrial habitat is to be removed during construction, mitigation measures are to be implemented to protect SAR. Coir fiber logs are less aesthetically pleasing as they begin to breakdown over time. There is the potential for erosion to reoccur if log biodegrade or shift overtime. High greater short-term and long-term impacts due to the loss of greenspace and recreational facility required to adequately realign the creek to be stable within the existing flow regime. However, design will have opportunities to improve habitat. If terrestrial habitat is to be removed during construction, mitigation measures are to be implemented to protect SAR. In the short-term, this alternative will have the most impact to adjacent landscaping and will not be aesthetic pleasing. However, in the long-term, the new channel designed would include aesthetically pleasing enhancement features such as plantings, walking paths, etc. Negative Impact Positive Impact

14 Criterion Significance Effects/Consideration Biological/ Physical/ Natural Environment High Geomorphology Preliminary Evaluation of Short List of Alternative Solutions Alternative 4: Partial Creek Realignment with Live Bank/Bio-Engineered Treatment 4A Live Crib Wall 4B Planting/Rip-Rap 4C Brush Mattress 4D Coir Fibre Logs Natural channel design principles are to be used in the design of the partial realigned. The design should also consider bank protection at the upstream and downstream transitions. The partial realigned should incorporate aquatic habitat improvements such as, but not limited to, root wads, boulder clusters, pools/riffles and riparian plantings, as well as velocity mitigation measures (i.e. deflectors, groynes, etc.) Natural channel design principles are to be used in the design of the partial realigned. The design should also consider bank protection at the upstream and downstream transitions. The partial realigned should incorporate aquatic habitat improvements such as, but not limited to, root wads, boulder clusters, pools/riffles and riparian plantings, as well as velocity mitigation measures (i.e. deflectors, groynes, etc.) Natural channel design principles are to be used in the design of the partial realigned. The design should also consider bank protection at the upstream and downstream transitions. The partial realigned should incorporate aquatic habitat improvements such as, but not limited to, root wads, boulder clusters, pools/riffles and riparian plantings, as well as velocity mitigation measures (i.e. deflectors, groynes, etc.) Natural channel design principles are to be used in the design of the partial realigned. The design should also consider bank protection at the upstream and downstream transitions. The partial realigned should incorporate aquatic habitat improvements such as, but not limited to, root wads, boulder clusters, pools/riffles and riparian plantings, as well as velocity mitigation measures (i.e. deflectors, groynes, etc.) Alternative 2: Full Creek Realignment High Extensive realignment through the study area, including areas that are currently not exhibiting any problems. Straightening or realigning the creek could have negative impacts upstream and downstream. New channel would be designed to be stable within the existing flow regime. Socio-Economic & Cultural Environment Overall Evaluation of Biological/Physical/Natural Environment Moderate Low Moderate Low Public Safety Surrounding Land use and Recreational Impacts Capital Cost Maintenance Costs Overall Evaluation of Socio-Economic & Cultural Environment Low eroding embankment will be stabilized and regraded to a safer slope. Construction will take a short period of time and safety can be mitigated through staging of the construction. Low proposed partial realignment of the creek will remain in the existing creek valley. Eroded back will be infilled and tie into the live bank. No additional lands will be required and therefore will have minimal impact on surround lands and recreational facilities. Moderate development and labour cost over other bioengineering approaches. Low - Long term sustainability and therefore reduced maintenance costs. Low eroding embankment will be stabilized and regraded to a safer slope. Construction will take a short period of time and safety can be mitigated through staging of the construction. Low proposed partial realignment of the creek will remain in the existing creek valley. Eroded back will be infilled and tie into the live bank. No additional lands will be required and therefore will have minimal impact on surround lands and recreational facilities. Lower development and labour cost over other bioengineering approaches. Low - Long term sustainability and therefore reduced minimal maintenance costs. Low eroding embankment will be stabilized and regraded to a safer slope. Construction will take a short period of time and safety can be mitigated through staging of the construction. Low proposed partial realignment of the creek will remain in the existing creek valley. Eroded back will be infilled and tie into the live bank. No additional lands will be required and therefore will have minimal impact on surround lands and recreational facilities. Lower development and labour cost over other bioengineering approaches. Moderate - less effective on lower banks due to washout during high flood events and higher velocities and therefore on-going maintenance required to ensure vegetation continues to establish and hasn t washed out during high flood levels. Low eroding embankment will be stabilized and regraded to a safer slope. Construction will take a short period of time and safety can be mitigated through staging of the construction. Low proposed partial realignment of the creek will remain in the existing creek valley. Eroded back will be infilled and tie into the live bank. No additional lands will be required and therefore will have minimal impact on surround lands and recreational facilities. Moderate- complex and relatively expensive technique compared to other bioengineering approaches. High coir logs will biodegrade overtime and therefore don t have a long effective life. Coir logs will need to be maintained and replaced. High Long construction period which will have an impact on residence, recreational activities and school. However, in the long term it will resolve a public safety concern and provide an aesthetic pleasing environment. High the realignment will not stay within the existing creek valley. Additional land would be required for the full realignment, which would extend into the adjacent recreational faculties. Largest construction area High development and labour cost over other alternatives. Low - Natural channel design requires minimal maintenance Negative Impact Positive Impact

15 Preliminary Technically Preferred Alternative Alternative 4: Partial Realignment with Live Bank/Bio-Engineering Treatment has been identified as the Preliminary Technically Preferred Alternative Solution. In accordance with the discussion and preliminary evaluation, a combination of Bio-Engineering treatments with a partial creek realignment are being proposed to stabilize the Carp Creek embankment within the study area and prevent any further erosion, as well as restore the embankment back to a natural and function feature of the watercourse. Applications and Effectiveness: Live crib walls are effective means of erosion protection on outside bends of creeks that experience high flood levels and fast flowing creeks, as well as they are affective where space is limited and a more vertical structure is required; Rip-rap is an appropriate protection measure to stabilize the toe of slope and prevent undermining; Combination of Bio-Engineering treatments (live crib wall, live stakes, planting and rip-rap) will help maintain a natural embankment appearance, as well as provides terrestrial, fish, aquatic and SAR habitat, and Provides immediate protection from erosion, while established long-term stability.

16 Next Steps & Schedule Milestone Deadline Public Information Centre Comment Expiry March 26, 2018 Select Technically Preferred Alternative March 30, 2018 Detail Analysis of Environmental Impacts of Technically Preferred Alternative April 6, 2018 Prepare Project Plan Report and Preliminary Design May 4, 2018 Mandatory Consultation - Notice of Filing to Interested Persons/Parties (30 day review) May 25, 2018 Deadline for Comments and Part II Orders June 29, 2018 For further information on the Carp Creek Embankment Restoration Project, please contact: John Price, Project Manager, Director, Water Resources Engineering Mississippi Valley Conservation Authority Highway 7 Carleton Place, ON, K7C 3P1 Phone: Ext. 258 Fax: jprice@mvc.on.ca McIntosh Perry Consulting Engineers Ltd. Lisa Marshall, P. Eng. Project Manager/Environmental Engineer 115 Walgreen Road, R.R.3 Carp, ON, K0A 1L0 Phone: ext Fax: l.marshall@mcintoshperry.com The Preliminary Project Plan Report is currently available for viewing on MVCA website s (