Cataraqui Region Conservation Authority March 29, 2019 Brent - - PowerPoint PPT Presentation

Cataraqui Region Conservation Authority March 29, 2019

Brent Parsons, M.Sc., Senior Aquatic Scientist Hutchinson Environmental Sciences Ltd.

 Assessment of Municipal Site Evaluation

Guidelines for Waterfront Development in Eastern Ontario’s Lake Country

 Review and Analysis of Existing Approaches for

Managing Shoreline Development on Inland Lakes

 District of Muskoka Lake System Health Program  Lac La Biche Sensitive Habitat Index Mapping and

Shoreline Management Guidelines

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 Evaluation of lake characteristics

• Focused on phosphorus
• Help to determine effectiveness of old site evaluation

guidelines (Michalski and Usher, 1992)

• Trends in Total Phosphorus of heavily developed lakes

between 2002 and 2012

• Lakes:

 MVCA – Kashawakamak, Mazinaw, Sharbot  RVCA – Otty, Upper Rideau  CRCA – Buck, Charleston, Indian, Loughborough

• Trends either sporadic (MVCA) or declining (RVCA, CRCA)

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5 10 20 30 40 1996 1997 1988 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 TP (ug/L) L) Year Upper Rideau - Site 1 Upper Rideau - Site 2 0.0 5.0 10.0 15.0 20.0 25.0 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 TP (ug/L) L) Year Charleston - Site 1 Charleston - Site 2 Charleston - Site 3 Charleston - Site 4 Charleston - Site 5 Charleston - Site 6 Charleston - Site 7 0.0 5.0 10.0 15.0 20.0 25.0 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 TP (ug/L) L) Year Sharbot - Site 4

 Assessment criteria

• Soils
• Slope
• Vegetation

6 Soil Character Soil Depth Chemical Analyses Deep Soils Shallow Soils Loam Sandy Loam Silty Clay Coarse sand and gravel Site Sensitivity 0 - 5% 5 - 13% 13 - 20% >25% Site Sensitivity Dense Understory Dense Canopy Sparse Canopy Sparse Understory Site Sensitivity

 Mitigation Measures

• Erosion and Sediment Control
• Shoreline buffer
• Sewage systems

7 Minimal Buffer (30m) Larger Buffer Site Sensitivity Moderately Coarse Soils Coarse or Fine Soils Deep Soils Shallow Soils Flat Terrain Steep Terrain Dense Vegetation Sparse Vegetation or Transformation to Ornamental Lawn Site Sensitivity

Conventional Septic System and Leaching Bed Tertiary Treatment Site Sensitivity Moderately coarse soils Coarse or fine soils Deep Soils Shallow Soils/Bedrock Flat Terrain Steep Terrain Dense Vegetation Sparse Vegetation Site Sensitivity

 Other Considerations:

• Natural heritage features
• Lakeshore Capacity Assessment
• Recreational Carrying Capacity
• Lake Trout habitat

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 Evaluation Criteria Checklist

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a. Site Description

• Topographic features

✓

• Natural hazards such as areas prone to flood or erosion

✓

• Watercourses, ponds, wetlands

✓

• Lot size, frontage, depth, area, shape

✓

• Permanent and intermittent streams

✓

• expected path of surface runoff

✓

• Aquatic vegetation & ecological description

✓

• Terrestrial vegetation community

See Table 5 for scoring b. Soil Characteristics

• Document and map soil conditions

✓

• Characterize soils used for leaching beds

✓

• Characterize native soils in mantle

✓

• Location of leaching bed

✓

• Pathway of subsurface flow relative to lake

✓

• Manual auguring to determine soil depth

See Table 5 for scoring

• Sources of suitable soil for raised fields

✓

• Soil Character - type, texture, colour

See Table 5 for scoring c. Slopes

• Site contours

✓

• Slope areas (0-10, 10-15, 15-20, 20-25, >25%)

See Table 5 for scoring

• Depressions and gullies that channel water

✓

d. Vegetation cover

• Map location and character of shoreline &

See Table 5 for scoring upland vegetation

• Photographic documentation

✓

• property shoreline (from lake)

✓

• tile field along direction of flow

✓

• building envelope shortest dist to lake

✓ e. Description of how development will occur

• Building location

✓

• Septic system location

✓

• Parking and other hard surfaces

✓

• Proximity to significant features

✓

• geological

✓

• man-made

✓

• wetlands, streams, other water

✓ f. Standard mitigation measures to eliminate impacts of nutrient and sediment loading

• Detailed construction mitigation plan

✓

• Stormwater management plan including control of

runoff and other BMPs ✓

• Incorporation of “b” horizon soils

✓

• Minimum 30 m shoreline setbacks and buffer areas

✓

• Delineate building envelopes

✓

• showing setbacks from shore

✓

• showing yard setbacks

✓

• showing septics location

✓

• Show protection for natural vegetation

✓

• slopes and soil mantle for areas

✓

• utside of building envelope

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 Biophysical Site Scoring

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Site Characteristic Criteria Score Soil Depth Depth (cm) >150 100-150 2 75-100 4 50-75 6 25-50 8 <25 10 Soil Texture Type Percolation Rate Phosphorus Retention Capability Coarse sand and gravel Excessively rapid Low 10 Silty clay and clay Low to impermeable High 7 Well-graded sands Permeable to moderate Low to medium 5 Silty sand, clayey sand, silt and fine sand Moderate to low Medium to high 3 Sandy loam Moderate to low Medium to high 3 Loam Permeable to moderate Medium to high Soil Analysis If native soil between tile field and lake is > 1m deep, <1% CaCO3 and >1% Iron/Aluminum

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Slope Slope Class 0%-13% 13%-20% 8 20%-25% 10 >25% 12 Vegetation Vegetation Cover Type Undisturbed woodlands, old fields, and meadows Disturbed woodlands, old fields, and meadows 3 Close-seeded legumes (clover, alfalfa) and rotation meadows 5 Row crops 7 Fallow fields and base bedrock outcrops 10

Total Score Recommended Depth of Shoreline Buffer (m) 36-40 90 31-35 80 26-30 70 21-25 60 16-20 50 11-15 40 ≤10 30

 Conclusions

• Phosphorus concentrations in lakes in the area do

not appear to be increasing

• Literature reviews can be blurry but it’s clear that

site specific features should be taken into account

• Old approach has stood the test of time
• Evaluation criteria and biophysical site scoring are

effective tools for planners, lake managers, proponents, etc.

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 Review of 14 jurisdictions across North America  Shoreline management by:

• 1. Capacity

 development limits based on thresholds and densities

• 2. Best Management Practices

 BMPs and minimum development standards to mitigate impacts

• Classification – used to inform capacity and determine

BMPs/development standards

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 Capacity Tools

• Lakeshore Capacity Assessment
• Lake Trout Policy
• Recreational Carrying Capacity

 Mitigation Tools

• Stormwater Management
• Shoreline Buffer
• Septic System Design and Maintenance
• Minimum Development Standards
• Soils Assessment

 Classification Tools

• Water Quality
• Lake Features (e.g. depth, surface area)
• Responsiveness to Phosphorus
• Current Development

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Jurisdiction Building Setback (m) Septic Setback (m) Lot Size (ha) Lot Frontage (m) Elliot Lake 20

• 0.4

45 Kenora - Black Sturgeon Lake 20

• 0.8

61 (122 for restricted development area) Muskoka 20 30

• 60 (increased

frontages to a maximum of 120 m may be required adjacent to narrow waterways) Muskoka Lakes 20 30

• 60 (may be

increased due to natural constraints) Seguin 201

• 1 (1.2 for island

lots) 90 (120 for island lots) Lake Simcoe Protection Plan 15 (Town of Innisfil)

• CRCA, MVCA, RVCA

30 – 902

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(Rideau Lakes) Cariboo 7.6 35

• 46

Maine 23 - 763 30 0.19 61 New Hampshire

• 23 – 384
• 46

Minnesota 23 – 465

• 0.19 – 0.745

30 – 615 Wisconsin 23

• 0.19

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1may be increased to address water quality, wetland, fish habitat or other similar issues 2 with greater setback dependant on biophysical site criteria 3 depending on shoreland zone classification 4 depending on percolation rate of soil 5 depending on lake classification

• indicates that standard was not provided in the documentation reviewed, but for Ontario jurisdictions the OBC requirement is 15 m.

 Conclusions

• Lots of tools
• Challenging to monitor success of tools
• BMPs and high minimum development standards

can be protective of a variety of features and functions but enforcement is key

• Lake classification/screening recommended to

tailor capacity and mitigation tools to address specific features of lakes and watersheds

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 Program initiated in 1980s with regular review

and revisions. Has included 3 main components:

1.

Lakeshore Capacity Modelling of over 500 lakes

2.

Water quality monitoring of 190 lakes to track water quality, inform modelling and residents

3.

Official Plan policies that use the model and monitoring results to guide the amount and nature of development on individual lakes

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 Notable revisions of most recent approach:

• Eliminating classification of lakes based on

modelled estimates of phosphorus

• Increased focused on water quality monitoring

results

• Recognition of BMPs and development standards

that can mitigate impacts

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 Recommended approach

• 1. Higher minimum standard of protection for new

development and redevelopment

• 2. Classify lakes according to measured changes and
• bserved quality
• 3. Implement enhanced planning requirements,

BMPs and a causation study for individual lakes based on triggers

 Triggers:

 10-yr average phosphorus concentrations >20 ug/L  Increasing trend in phosphorus  Occurrence of blue-green algal blooms

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 Public concern

with algal blooms and Walleye populations

 Purpose was to

identify and protect sensitive areas during shoreline development

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29 Activity Shore Zone Colour and Activity Risk Modifier Red Orange Yellow Grey Zone of Sensitivity Aquatic vegetation removal H H H M H Beach creation above HWM H H M M H Beach creation below HWM H H H H H Boat house (below HWM) H H H M H Boat launch upgrade H H H H H Boat lift - temporary M M L L H Docks Refer to DFO Guidance, dock type, etc. Dredging H H H H H Dredging - maintenance/previously approved H H H H H Elevated boardwalk below HWM H M M M H Erosion protection (hard engineered) H H H M H Erosion protection (soft bioengineered) H M L L H Foreshore sediment disturbance and removal of lakebed substrates H H M M H Infill H H H H H New boat launch H H H H H Over water-piled structure (i.e. building, house, etc.) H H M M H Public beach maintenance M L L L M Septic application Refer to residential permitting requirements Installation of treated effluent discharge pipe H H M M H Upland vegetation removal H M M M H Waterline drilled H M L L H Waterline trenching H H H M H

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Table 1. Decision-Making Flowchart Identify Activity Risk Determine review process, permits, approvals and authorizations required through consultation with Lac La Biche County, Alberta Environment and Parks, Fisheries and Oceans Canada and

• ther relevant regulatory agencies (see Section 4.1.2)

Identify Aquatic Habitat Index Shore Zone Colour and Zones of Sensitivity in project area High Risk Low Risk Medium Risk Complete Environmental Impact Study Project declined because of potential impacts Project approved because of sufficient mitigation Implement appropriate Best Management Practices and mitigation measures so that works adhere to relevant policy Proceed with project subject to conditions included in approvals documentation (if applicable) Implement appropriate Best Management Practices and mitigation measures so that works adhere to relevant policy Abandon project, alter scope of project or move to a different location Project review by regulatory agencies

 A wide variety of different tools available to

manage shoreline development

 Lake and watershed characteristics should be

accounted for where possible (i.e. classification approach)

 Approaches need to stay up to date based on

monitoring and research

 Enforcement is integral for BMP-based

approaches

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 brent.parsons@environmentalsciences.ca  (705) 645-0021  http://environmentalsciences.ca/newsite/  Thanks!

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