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