Loading...
HomeMy WebLinkAbout200304 CC Wksn PresentationFlood Risk Reduction –Draft Strategy Review City Council and task force work session March 4, 2020 Task Force Framework Strategy Examples at 4 scales of action PAST to FUTURE Next steps EdinaMN.gov 2 Outline Members / Introductions •12 Meetings, 9 months Value to Staff •Gaps; Service expectations vs. reality •Value and values •Shared language •Common problem, leading the conversation EdinaMN.gov 3 Task Force Technical analysis What is valuable, when? What matters, where, to whom? What is flooding? How we view risk Drivers of increasing flood risk Areas of work EdinaMN.gov 4 Framework Surface water Groundwater Sanitary backflow Pathways to structural flood risk EdinaMN.gov 5 EdinaMN.gov 6 Climate / Natural Environment Varies in time •Short term weather •mid-term season •long term climate Varies in place •Uphill / slopes / low area •Near creek, wetland, lake How we view risk 7 Flood Exposure •Degree to which property, homes, buildings, infrastructure and other asset come into contact with flood water •Depends on runoff, flow, storage, drainage, groundwater, and soils. Varies spatially, some area near low areas and flow paths are exposed How we view risk EdinaMN.gov 8 Flood Vulnerability •The degree to which exposed assets are unable to resist flooding and are damaged by floods •Depends on the extent of assets on the land, both public and private, and how well it can resist flooding, or limit damage when flooded How we view risk EdinaMN.gov 9 How we view risk Key equation Flood risk = climate x exposure x vulnerability Applied at varying scales; system, class, component City Example: Sanitary system, sanitary sewer lift station, electrical components Personal Example: Dwelling, foundation/basement, individual window well EdinaMN.gov 10 Areas of Work Technical analysis / quick wins •Infrastructure •Regulation •Emergency Services •Outreach and Engagement Task Force Discussions •What we expect vs. what we get and future vision •Shared view of risk, what we value and personal values •Potential actions / prioritization EdinaMN.gov 11 Drivers of increasing risk Leading drivers TOP –Climate change has already, and will expose more assets to flooding in the future. This driver is predicted to overwhelm the other drivers in terms of scale. SECOND –Private and public asset and infrastructure are both exposed and vulnerable. Public infrastructure can define flood exposure for different points in the landscape, and serve as a pathway for private risk EdinaMN.gov 12 Drivers of increasing risk Other drivers THIRD –Most of the land use decisions have already been made, and cannot be unmade, we choose to drain the landscape, connect it to the waters, and develop over waters. There is additional demand for drainage that can reduce vulnerability, but marginally affects flood exposure downstream. FOURTH –There is increasing demand for use of land, imperviousness drives runoff in small storms and marginally affects flood exposure in large storms How we view risk Areas of work Drivers of increasing flood risk EdinaMN.gov 13 Framework Comprehensively reduce the risk of flooding throughout the community In our work with the community we will; •make flood information available to all and promote flood awareness •work to help people stay safe in floods •help people protect their properties from flooding and the affects of floods •plan public streets and parks to accept and transmit flood waters to reduce the risk and disruption of related city services EdinaMN.gov 14 Strategy Comprehensively reduce the risk of flooding throughout the community In our areas of work; •Infrastructure: We will renew our infrastructure and operate it to reduce risk •Regulation: We acknowledge competing demands of land use and addressing drainage, groundwater and surface water issues. We help people solve issues without harming another •Outreach and engagement: We make flood information available and give people tools for flood resilience •Emergency Services: We help people prepare for floods, remove people from harm during floods, and recover after floods. EdinaMN.gov 15 Strategy 16 FUTURE How we view risk •Systems, awareness, dynamic •Climate x exposure x vulnerability Areas of work •Infrastructure, regulation, outreach & engagement, emergency services •Risk management Key Trends •Climate change, aging infrastructure PAST How we view risk •Reactive, static •probability x consequence Areas of work •Infrastructure and emergency response •Bigger pipes, risk transfers, rescue Key Trends •Drainage, land development EdinaMN.gov 17 Framework FUTURE •Freeways shut down, sewers back up, flooded basements, less? •Staff reallocated to call center, provide safety advice only •Emergency response plan brings resources to problems faster •Predictive pumping make a little extra room based on forecasts •Capital plan is proactive and prioritized, no need for reactive change PAST •Freeways shut down, sewer backups, flooded basements •Call center overwhelmed •After action, look to blame, solve ‘problem areas’ that flooded by transferring risk downstream EdinaMN.gov 18 ’87 style flood response FUTURE •Add storage in streets and right of way (lower streets, tree trenches, etc) •Add new curb and gutter, plan emergency flow paths •Rebuild catch basins, add needed inlets •Review pipe sizes, repair and upsize only where we make room with storage downstream PAST •Add new sump drainage pipe •Add new curb and gutter •Rebuild catch basins Neighborhood and parks reconstruction EdinaMN.gov 19 FUTURE •Erosion and stormwater standards •Regional and local flood elevation standards, grading and drainage review •Impervious limit •Technical assistance available •People are flood aware, help others •People with exposure have taken actions to reduce vulnerability •Most critical at-risk structures removed or redeveloped PAST •Erosion control standards •Regional flood elevation standards •No impervious limit •No technical assistance Residential redevelopment, individual home drainage issue EdinaMN.gov 20 FUTURE •once per five year proactive inspection and preventative maintenance •Preventative debris removal •Adopt-a-drain, community cleanups •Enhanced street sweeping •Trouble spot retrofits •Smart infrastructure, remote level awareness, predictive pumping control PAST •Reactive maintenance, run-to-failure •Clear clogs •2 per year street sweeping Stormwater infrastructure, operations and maintenance EdinaMN.gov 21 FUTURE •Risk Management •Comprehensive areas, service based •Policy and program •Adaptation, design for future based on increasing risk of climate change •Community focus, build capacity for resilience •$xx.xx? PAST •Problem solving •Focus area, complaint based •Reactive •Design for past, assume future looks the same •Expert focused, technical •Storm Utility fee $37.59/quarter EdinaMN.gov 22 Water resources paradigm Indirect •Impervious Surface Planning Commission Proposal •Climate Action Plan •2020-21 Budget workplan •2021-26 Capital Improvement Plan (CIP) •2022-23 Budget Direct •Finalize framework and strategy for Council consideration •Order major amendment to Comprehensive Water Resources Management Plan, align policy with strategy and do tactical planning for water resource program expansion •Create first comprehensive flood risk reduction plan with public engagement ahead of Morningside 2022-23 reconstruction projects and Weber park development EdinaMN.gov 23 Next Steps