CVC Wetland Restoration Strategy

Transcription

1 CVC Wetland Restoration Strategy

2 Overview Strategy Development Process Methodology & Analysis Modules Strategic Units & Results Strategy Integration in CVC Programs

3 Strategy Development Wetland Restoration Strategy Steering Committee Dougan & Associates, Snell & Cecile Environmental Research, AMEC/ Philips Engineering LTD CVC Staff MNR Ducks Unlimited

4 Analysis & Methods To use existing GIS data for broad scale screening of : A) Potential Wetland Restoration Tracts B) Potential Wetland Rehabilitation Tracts C) Priority Wetlands for Climate Change Adaptation Measures

5 Priority Tracts for Wetland Restoration Methodology

6 Module 1: Potential Wetland Restoration Tracts Potential Restoration Sites Across CVC include: - Tracts include Gartner-Lee(2005) with some exclusions - CVC s Wet Meadow (ELC) - Alluvial without natural cover or development - Headwater swales located by 30m buffer either side of a 0 and 1 order stream with <2% slope and not currently natural cover - A minimum threshold of 0.1ha was chosen to balance data resolution

7 Module 2: Feasibility - Proximity to a water source - Proximity to seed source - Avoidance of high capability or high feasibility agricultural land - Land that is not currently being used for an incompatible purpose - Ease of access - Location in zones where natural area restoration is encouraged ie CVC property.

8 Module 3: Sensitivity of Potential Wetland Tracts To Climate Change - The dependability of the water source in the context of a general drying trend (ie groundwater fed the least sensitive, rainwater fed the most) - Landscape position floodplains subject to more extreme flows; - Nearby land use: both lack of adaptation & assisting linkage to other wetlands

9 Module 4: Subwatershed Priority For Improved Wetland Services - Current wetland extent (CVC 2006 wetland) - Current forest extent (CVC ELC) - Land permeability (Ontario Geological Survey, 2003)

10 Module 5: Landscape History - From available digital data, landscape history can include estimates of: - % of original wetlands that have been converted from presettlement Summaries / sub-watershed representativeness of current wetlands relative to pre-settlement and current conditions - Distribution of drains and tile - Comparison of the general spatial distribution of wetlands across each subwatershed: presettlement and current

11 Module 6: Tracts Flagged For Potential Function - Potential functions if wetland is restored: - Flood attenuation - Groundwater recharge, if headwater, isolated or artificially drained - Water quality improvement, if near contaminating use, or organic soils (P source if drained) - Potential natural heritage connectivity - Potential social functions

12 Priority Sites For Wetland Rehabilitation Methodology

13 Module 7: Estimates Of Degraded Wetland - Degradation through water related effects can occur through stream modification - Wetlands that have been leveled of micro topography by historical agriculture - Degradation from land uses with contaminated runoff - Downstream floodplain wetlands subject to stresses of changed flows and contaminated water

14 Module 8: Climate Change Sensitivity of Existing Wetlands - Module assumes warmer drier conditions: - Sensitivity depends on: - Dependability of the water Landscape context - Proportion forested - Nearby land use

15 Priority For Climate Change Adaptation Measures Methodology

16 Module 9: Importance of Wetland Services - Wetland Evaluation: OWES indicates value of wetlands service - PSW = high, LSW or field verified = Med, unconfirmed = low

17 Strategic Units Data analyzed for each module and three strategic units Greenbelt Least need for additional wetland services Lowest short term priority Focus Orangeville & Caledon creek and agricultural till plains for this belt Urban Belt High priority need for wetland restoration Limited wetland restoration potential outside the floodplain and parts of the shoreline Source control wetlands and LID most appropriate White Belt Greatest need for wetland restoration Changing land use provides considerable opportunity

18 Strategy Integration In CVC Programs CVC Restoration & Stewardship utilizing strategy as a project screening tool Input into Sub-watershed studies Targeted outreach initiatives

19 Contact Information Paul Biscaia Restoration Technician Credit Valley Conservation Ext 427