River Restoration Practices: Comparison of British Columbia and Central European Practices by David Matsubara and Dave Murray Add Map of North America VANCOUVER, Wa.
Add Map of Vancouver OUTLINE Introduction Introduction European/Austrian Framework British Columbia Experience Example Techniques Summary
BASIS FOR DISCUSSION Austrian Situation: Long history of river regulation Highly populated areas Compounded land use issues British Columbia Relatively young history, less degraded systems Increasing population Land use in urban areas... Austrian River Restoration LEGISLATIVE - POLICY MECHANISMS Austrian Water Act (1990) EU Life Projects (Natura( 2000) EU Water Framework Directive a framework for the protection of inland surface waters, transitional waters and groundwater; protection of all good or high quality water resources an objective of at least good water status in a 15 year period;
Austrian River Restoration Assessment of Ecological Integrity Development of a undisturbed reference state (Leitbild) Identification of deficits or deviations Development of restoration actions Monitoring of Ecological Integrity maintaining or restoring the key processes that enable floodplain systems to maintain, repair, and regenerate themselves (Sparks, 1995) Ecological Integrity Austrian Water Act 1. Pristine 1-2. Slightly Disturbed 2. Moderately Disturbed 2-3. Significantly Disturbed 3. Heavily Disturbed 3-4. Very Heavily Disturbed 4 Completely Disrupted EU WFD High Good Moderate Poor Bad (Chovanec,, et al, 2000)
Austrian Assessment Method ABIOTIC Hydrology / Hydraulics / Connectivity Morphology / Habitat / Structures / Bedload BIOTIC Multi Level Assessment of Fish Assemblages Macroinvertebrate assemblages PHYSICAL-CHEMICAL CHEMICAL PARAMETERS Biological water quality assessment Ecotoxicology (Chovanec et al., 2000) Reference - Leitbild Visionary Leitbild - Defining a High or Pristine State from reference sites historical morphological data historical fish data reference models Operational Leitbild - Defines the best state within the constraints of the system
Restoration of Deficits / Deviations Scales of Restoration
Specific Restoration Techniques B.C. Experience Short restoration history Forest Renewal Program - mostly rural Urban stormwater and creek issues Applications of bioengineering...
Current Restoration Initiatives In the Vancouver Region and other population centres, restoration tends to be development driven Federal Fisheries policy is for No Net Loss for instream works No policy or driver for pure large-scale restoration
Typical Urban Restoration Projects
Bioengineered Bank Protection Foundation course of rock Brush layers of live cuttings Soil wraps (vegetated geogrids) encapsulating soil Planting of the bank face Insert soil wrap graphic series Mackay Creek Toe Erosion Before
Brush Layer 3 Soil Wrap 3 Live Willow Staking Brush Layer 2 Soil Wrap 2 Brush Layer 1 Soil Wrap 1 Rootwad Bank Regrading Riprap Foundation Course Toe Excavation Curlex
Foundation layer
Completed Soil Wrap 1 month after construction
High flow performance 1999-9 months after construction
1998 2001 3 years after construction May 2003 (5 yrs after construction)
Eroding banks and poor riparian vegetation 3 months post-construction
3 months post-construction May 2003 (2 years after construction?)
Thain Creek Daylighting Project Site Location
Access DISTRICT OF NORTH VANCOUVER Westview Drive CITY OF NORTH VANCOUVER To Highway 99 Pre-construction south side corridor Pre-construction north side of corridor
Bioengineering Installation Seeded channel with brush layers Vegetated geogrid or soil wrap Completed soil wrap prior to landscaping
Final landscaping and fencing
Spring 2001 August 2003
Vegetation and Planting Lessons Consult plant specialist Appropriate plant species Plugs, cuttings, container stock Favourable growing conditions Irrigation requirements Timing, harvesting, storage Integration with rock foundation Constructability Lessons Site access with minimum disturbance Design in equipment access routes Plan project sequence Consider material availability Involve the builder and maintenance staff in design process
Comparison between Regions Austria High species divesity Highly fragmented Hydrological impacts (hydro) Large scale planning Passive restoration implementation British Columbia Anadromous focus Some large barriers (dams) Regulation in urban/populated areas Restoration occurs at smaller scales, or as rehabilitation efforts Conclusions - Austria Perspective Greater awareness and focus on river restoration in Austria Legislative and Policy Instruments are driving the movement Greater emphasis on basin scale restoration Very methodical approach to assessment and monitoring
Conclusions - BC Perspective Good experiences in urban sites Use of bioengineering techniques adopted from Europe are effective Need to implement at larger scales with greater restoration of natural processes Need better assessment and monitoring of streams to assess requirements and performance Policy instruments within urban regions are emerging but are not as comprehensive Questions? River Restoration Practices: Comparison of British Columbia and Central European Practices by David Matsubara and Dave Murray