Delta Flood Protection Strategy Update May 16, 2016
Presentation Overview 1. Background 2. Understanding the Dike Reaches/Issues 3. Future Dike Improvements 4. Next Steps
Boundary Bay Village March 10, 2016
East Delta Dike March 10, 2016
1. Background 1.1 Delta River & Sea Dikes Dikes are essential to protect: > $6.5 billion of land and infrastructure, Agricultural land Ladner (major dike breach could cause $1-$3 billion in damage, annual B/C ratio 2.5:1 over 50 yrs B/C >100:1 ) Since 2000 Delta with Provincial and Federal funding has spent more than $10 million on dike works, drainage pump stations, and floodbox repairs.
1.2 Provincial Guidelines Coastal Sea Level Rise Sea Dike Guidelines o Local governments should develop a locally appropriate long term flood protection strategy Seismic Design Guidelines o Dike upgrades requiring Dike Maintenance Act approval need a seismic assessment. (Important to do upfront, could change dike alignments.) Flood Hazard Area Land Use Management Guidelines Draft Amendments for Sections 3.5 & 3.6 o Proposed land use guideline amendments will require that land use planning in coastal areas considers sea level rise (2100 and 2200).
2. Understanding the Dike Reaches/Issues Coastal vs. River Dikes Foreshore Protection Provincial Regulatory Considerations o Sea Level Rise (Land Use Mgmt Guidelines, Sea Dike Guidelines) o Dike Seismic Stability Assessment
2.1 Delta River & Sea Dikes G F H I J A Dike Reaches A. East Delta Dike B. Beach Grove Seawall C. Boundary Bay Village D. Tsawwassen Beach E. Tsawwassen First Nation F. Brunswick Point G. Westham Island H. River Road West/Ladner I. Tilbury River Road East J. Annacis Island E B Dike Location Dike Elev. 3.5 m D C
2.2 Sea Level Rise Median sealevel rise of o 0.3m-0.5m by 2050 o 1.0m+0.2m by 2100 o Flood frequency will increase (i.e. increasing risk of dike overtopping)
3. Flood Protection Improvements 3.1 Update Development Policy 3.2 Dike Improvements / Upgrades
3.1 Update Development Policy Dike Elevation for New Developments Update Flood Protection Policy Meet future dike hieght requirements, Review Flood Construction Levels Review Official Community Plan Development Permit Areas for flood protection and report back
3.2 Dike Improvements / Upgrades Dike Seismic and Elevation Studies Phased Dike Upgrading / (Excavation fill program) Long Term & Sustainable Funding Program Ongoing Monitoring of Sea Level Rise
Dike Seismic and Elevation Studies Undertake a comprehensive seismic study for Delta dikes Dike Maintenance Approval requires that dike upgrades address seismic stability New developments adjacent to dikes to meet seismic requirements Foreshore/water level analysis
Phased Dike Upgrading (35 year Program) Flood Protection Levels to 2050 and 2100 Dike Height (m) Dike Reach Adapted From - Cost of Adaptation-Sea Dikes and Alternate Strategies -Oct 2012 Ministry of Forest Lands and Natural Resource Operations
Phased Dike Upgrading (35 yr Program) cont d Planning / dike upgrade fund for 67 km of dikes October 2012 Cost of Adaptation study by Province estimated 2100 dike upgrade cost for Delta $1.9 billion Phased program with Phase 1 upgrade to 2050 (i.e. over 35 years) preliminary costs estimated at more than $350 million (preliminary planning/studies, land/srws, managed construction in phases) excluding extensive seismic upgrading
Phased Dike Upgrading cont d Assess foreshore protection improvements Evaluate options for protecting the access to Ladner harbour, and improving flood protection for downtown Ladner. Commence a 2050-2100 phase of flood protection works (based on the 2050 observed and predicted sea level rise)
Long Term and Sustainable Funding Program Conduct a more detailed assessment of upgrades and costs, after seismic studies. Work with the Finance Department to develop dedicated funding for a long term dike upgrading program. o. (eg. 1/3 share of a Municipal/Provincial/Federal cost shared program, dike levy for Municipal share) Participation in the Regional Flood Protection Studies and funding model development. Solicit senior government cost sharing support. (e.g. Federal, Provincial, Port Metro Vancouver)
Ongoing Monitoring of Sea Level Rise Sea Level Rise Monitoring Coastal Land Monitoring Participate in Regional Flood Protection Studies
4. Next Steps Review internal and external stakeholders (Interest Groups, Advisory Committees). 2017 Business Plan Workshop funding discussion Future Dike planning studies: Dike Elevation and Seismic Studies Water Level/Foreshore/ Flood Construction Level Studies. Commence planning for a filling/dike raising program. Ongoing work to address existing deficiencies.
Questions