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Upper Little Bow River Restoration Plan
Presentation Overview1. Upper Little Bow Restoration
Plan Purpose & Objectives2. Study Area and Reach
Descriptions3. Restoration Plan Scope of
Work4. Work Completed to Date5. Reach Descriptions,
Concerns and Restoration OptionsReach 1Reach 2Reach 3Reach 4
6. Future Work
1.0 Purpose and Objectiveso Improve the ecological function of the river segment o Improve the river water quality towards meeting federal
and provincial guideline valueso Provide preliminary treatment for collected stormwater
discharging to the river o Address citizen’s concerns regarding nuisance issues (i.e.
odour, garbage)
2.0 Study Area: Upper Little Bow River
Facts about the Upper Little Bow (ULB) Study Area: o 1660 m headwater segment of Little
Bow River
o Located entirely within the Town
o Divided into 4 reaches for planning:
Reach 1o Originates at 5th Ave SE, ends at 8th Ave
SEo Flows south to Reach 2
Reach 2o Originates at 8th Ave SE, ends at 10th
Ave SEo Flows south, as a tributary of Reach 3
Reach 1
Reach 2
Reach 3
Reach 4
2.0 Study Area: Upper Little Bow River
o Divided into 4 reaches for planning:
Reach 3o Originates at 9th Ave SE,
ends at 12th Ave SEo Flows southeast into Reach
4
Reach 4o Originates at 12th Ave SE,
ends at 5th St. SEo Flows southeast
Reach 3
Reach 4
Reach 1
Reach 2
3.0 Scope of Work
o Phase 1. Hydrologic Assessment
o Phase 2. Remedial Option Analysis
o Phase 3. Conceptual Restoration Action Plan and Public Consultation
o Phase 4. Detailed Design (phased approach)
o Phase 5. Construction and Clean-up (phased approach)
4.0 Work Completed to Date
o Phase 1. Hydrologic Assessment – Initial Reports Complete
• Assessed hydrologic (groundwater and surface) influences, potential impacts and water quality
• Work is ongoing to answer questions related to hydrology and related impacts
• REPORT: June 2010 – Upper Little Bow River Hydrologic Assessment• REPORT: December 2010 – Little Bow River Water Quality Monitoring
4.0 Work Completed to Dateo Phase 2 – Remedial Option Analysis – Complete
• Developed high-level restoration options and assessed potential impacts for regulatory review
• Met with Alberta Environment and Water (AEW) to review options & determine next actions
• Reviewed options with Fisheries and Oceans Canada (DFO)
• REPORT: September, 2010 – Upper Little Bow River Restoration Options and Impact Assessment (Draft for Discussion)
• REPORT: February, 2011 – Conceptual Remedial Action Plan for Upper Little Bow River (Draft)
4.0 Work Completed to Dateo Phase 3 – Conceptual Restoration Action Plan &
Stakeholder Consultation – Current
• Prepared preliminary conceptual designs and best management practices proposed for restoration
• Undertook work to refine restoration designs
• Performed high-level risk review (in review)
• Presenting design options to public for review and feedback at open house
• Finalizing plan and conceptual designs based on stakeholder feedback
• REPORT: September, 2011 – Upper Little Bow Sediment Survey (Draft Report). This report present results from the sediment survey carried out in Reach 1 and Reach 3
• REPORT: March, 2012 – Risk Review for the Upper Little Bow River, High River Alberta
5.1 Concerns & Restoration Options Reach 1
o Reach 1 is located between 5th Ave SE and 8th Ave SEo Concerns Include:
• Odour and aesthetics• Sedimentation & channel morphology impacts due to dredging• Poor sediment and water quality• Garbage and debris
Looking downstream from start of Reach 1
Reach 1 outlet culvert
Reach 1 Restorationo Clean-up debris
o Remove sediment
o Install forebay at main upstream inleto Trap sediments
o Applied for all options (see below)
o Treat other stormwater inflows• Grassed swales, bioswales
o Channel restoration options • Options 1a: Maintains existing channel
features including open water areas and morphology
• Option 1b: Maintains existing channel morphology but use imported fill to limit depth of pools
• Option 2: Channelizes “pool” areas using imported fill, establishes riparian areas and re-grades/fills channel to improve flow and reduces stagnation
Reach 1 (OPTIONS) Aquatic Benefits/ Disadvantages
o Option 1a Maintains existing structure, removes sediment• Treats incoming stormwater and reduces sediment in channel• Maintains open water areas for waterfowl• Does not addresses stagnation or odour issues
o Option 1b Maintains pools but minimizes pool depth by replacing channel bottom with clean sand/gravel fill
• Treats incoming stormwater and reduces sediment in channel• Decreases pool depths and storage resulting in a slight increase in flow velocity• Provides “clean” channel bottom habitat for aquatic species
Reach 1 (OPTIONS) Aquatic Benefits/ Disadvantages
o Option 2 Channelizes pool areas and re-grades• Treats incoming stormwater and reduced sediment in channel• Increases flow and decrease stagnation, minimizing odour• Loss of open water habitat• Gain of riparian and flowing water habitat
5.2 Concerns & Restoration Options Reach 2
o Reach 2 is located between 8th Ave SE and 10th Ave SEo Concerns Include:
• Sedimentation • Garbage and debris
o Restoration:• Remove garbage and debris
Looking downstream into Reach 2 Reach 2 inlet culvert
5.3 Concerns & Restoration Options Reach 3
o Reach 3 is located between 9th Ave SE and 12th Ave SEo Concerns Include:
• Sedimentation • Garbage and debris• Decrease of Fall and Winter baseflow
Looking upstream from 12th Ave SE Looking east Reach 3
Reach 3 Restoration
o Clean-up debris and garbage o Undertake trials to remove sediments using low
impact methodso Treats all stormwater inflows
• Grassed swales, bioswales, oil-grit separators
Reach 3 Restoration
o Treatment of stormwater inflows will:
• Improve stormwater quality• Minimize suspended sediment entering the system
o Removal of debris and sediment improves channel water quality and channel bottom habitat
5.4 Concerns & Restoration Options Reach 4
o Reach 4 is located south of 12th Ave SE & northwest of 5th St SE
o Concerns Include:
• Odour • Sedimentation and debris• Limited riparian vegetation
Looking downstream to end of Reach 4
Looking west from 5th St SE
Reach 4 Aquatic Benefits/Disadvantages
o Debris and sediment removal will help reduce odourso Riparian vegetation will:
• Provide habitat for wildlife• Reduce water temperature, increasing oxygen levels and encouraging use
by fish • Reduce odour• Reduce occurrence of algal mats
Looking west from Visitor Information Centre
6.0 Future Work
o Finalize conceptual design based on stakeholder feedbacko Prepare detailed designs and construction plans
• Phased approach with high-priority items addressed firsto Submit plans for regulatory review and obtain approvalo Perform works and execute plan using a phased approach