Artificial Wetland Creation as a Cost Effective ...€¦ · • Natural water table fluctuations:...
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Artificial Wetland Creation as a Cost Effective Reclamation Strategy By Ben Poltorak, Elizabeth Murray, Adam Dunn, Kris Christiansen, Perry Gerwing Project Proponent: Brenda McGinn
Transcript of Artificial Wetland Creation as a Cost Effective ...€¦ · • Natural water table fluctuations:...
Artificial Wetland Creation as a Cost Effective Reclamation Strategy
By Ben Poltorak, Elizabeth Murray, Adam Dunn, Kris Christiansen, Perry Gerwing
Project Proponent: Brenda McGinn
Site Details
Site was located in:• Wooded poor fen• Limited access
Surrounding area was forested:• Labrador tea & black spruce• Wildfire burned the area in 2011
Required remediation due to:• Pipeline release
Oil emulsion – 2 breakpoints• Contaminants
Salt & PHC• Spill response was immediate• Volume of soil removed
2015: 9,500 m³ Reclamation was partially
completed
Site Location
BP #1
BP #2
Site Details
Site Details BP #1
Site Details BP #2
Remediation / Reclamation Goals
• Confirm complete remediation of site, soil and water,• Examine reclamation options for BP#1: Backfill, Constructed
Wetland, Others?• Construct a fully functional wetland compatible with the adjacent
ecosystem,• Establish a self-sustaining plant community where wildlife and
waterfowl can continue to succeed without human interaction,• Maintain equivalent land capability.
Wetland Design Details
• Natural water table fluctuations: account for the natural variation in a fluctuating water table
• Bathymetric contours: provide different littoral zones with areas of deep, shallow, and open water
• Organic soil: provide stable and suitable root, rhizome and seed substrate• Mineral soil: added to increase the littoral surface area • Shoreline: irregular shape and a variety of slopes • Depth: irregular to allow for a variety of habitat• Water recharge and discharge: allow precipitation and groundwater flow to
enter and exit the wetland • Vegetation: allow easy access to and exit from the wetland
Design Details
Based on:General Design Guidelines for a Constructed ‘Habitat’ Wetland –Boreal Forest Natural Region of Alberta.
Government of Alberta (2014).
Design Details
Typical profile for a constructed wetland habitat
Design Details
• Mineral soil used to fill grades • Organics removed from perimeter and
utilized as substrate• The shallow littoral zone represents 694
m² (53%) of wetland habitat• The deep littoral zone represents 345 m²
(26%) of wetland habitat
Design Details
Construction Details – February 2017
Construction Details
Construction Details
Construction Details
Construction Details
Construction Details
Construction Details
Mid-Season Site Visit (May 2017)
Mid-Season Site Visit (May 2017)
Mid-Season Site Visit (May 2017)
Cost of Construction
Wetland Construction Backfill
Consulting/Reporting $28,000 $20,000
Pipeline $8,000 $8,000
Heavy Equipment $25,000 $80,000
Light Equipment $3,500 $3,500
Total $64,500 $111,500
42% Reduction in reclamation costs
Monitoring Requirements
• Annual reporting to regulator,• Site visits with regulator,• Monitor until equivalent land
capability is reached,• Monitor and manage weeds,• Document wildlife sightings,• Document plant species and
diversity,• Allow for natural ingress.
Vegetation Assessment – October 2017 (7 Months)
Area was divided into 6 strata:
• Background Treed Fen Littoral Zone
• Reclaimed Backfilled Excavation Cleared Treed Fen
• Constructed Fen Littoral Zone
Established115 randomized plot locations:• Each plot was assessed for:
Bryophytes: Sphagnum, red stem, nights plume etc.
Herbaceous/Forbs: Marsh reed, smooth brome etc.
Shrubs: Labrador tea, highbush cranberry etc. Trees: Black spruce, larch etc. Undesirables: Sweet clover, thistle etc.
• % cover was measured by visual area• height measured using a tape measure • Each plot was 1x1m in size
Vegetation Assessment Plot Locations
Background Treed Fen
Background Littoral Zone
Backfilled Excavation
Cleared Treed Fen
Background: Treed Fen
Background: Treed Fen
Background: Littoral Zone
Background: Littoral Zone
Reclaimed: Backfilled Excavation
Reclaimed: Backfilled Excavation
Reclaimed: Cleared Fen
Add picture
Reclaimed: Cleared Fen
Vegetation Assessment Plot Locations
Constructed Fen
Constructed Littoral
Constructed: Fen
Constructed: Fen
Constructed: Fen
Constructed: Littoral Zone
Constructed: Littoral Zone
Strata Comparison – Desirable vs. Undesirable Species
Ecosystem Recovery
Simpson’s Diversity IndexCompare diversity of each strata as an indication
of ecosystem recovery.
Range: 0 - 1
Ecosystem Recovery
Recovery of Vegetation
Constructed Fen Constructed Littoral Zone Backfilled Excavation
BP #1 BP #1 BP #2
Monitoring Requirements - Future
• Continue to monitor establishment for another growing season,
• Continue weed control activities,
• Regulator is pleased to receive reports,
• Continue to compare backfill scenario to constructed wetland features.
• Winter 2018: AER deemed the site closed
Thank You
