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Home My WebLink About9A Flood Response Policy PresentationFlood Response Policy City Council June 26, 2017 Flood Response Policy Why do we need a Flood Policy? •Flooding is an important community issue •Flooding impacts residents, businesses, emergency services, and other essential community services •Flooding events are relatively rare Flood Response Policy Why do we need a Flood Policy? •To define public/private responsibilities •To improve flood response •Faster response time •Better coordination •Improved communications •Stormwater Management and Flood Mitigation Study (2016) Flood Response Policy Watershed Basics •Upper Watershed Spring Lake Upper Prior Lake Lower Prior Lake  Minnesota River •Large area (about 19,000 acres or 30 square miles) draining to Prior Lake, with no natural outlet •Prior Lake-Spring Lake Watershed District (PLSLWD) completed the Prior Lake Outlet in 1983 Flood Response Policy Watershed Basics •Prior Lake has exceeded 904.0 in 6 different years after the outlet was constructed: •1983 (905.68) •1993 (904.64) •1998 (904.40) •1999 (904.78) •2001 (904.33) •2014 (906.17) Flood Response Policy 2014 Flood •First major flood event (>905) for Prior Lake since 1983 •City prioritized infrastructure protection, made resources available for private property protection (sandbags and sand), and provided street access as resources allowed •No model for coordination with other agencies and communications with the public Flood Response Policy Flood Response Policy 2014 Flood –Key Lessons Learned •Communications •Internal procedures for staff (daily briefings) •Coordination with key outside agencies •Messages for the public (website, media, neighborhood meetings) •Prioritizing Resources •Early identification of needed resources •Timely installation of infrastructure protection •Ensure other community priorities and services can still be met •Transportation •Importance of CR21 corridor Flood Response Policy Stormwater Management and Flood Mitigation Study (2016) Study Goals Included: •Characterizing watershed and update the flood model •Identifying flood damage reduction strategies •Evaluating cost/benefit of strategies •Developing an implementation plan Flood Response Policy Stormwater Management and Flood Mitigation Study (2016) Policymaker Goals: 1.Protection of Public Safety –maintain emergency vehicle access 2.Protection of Health and Safety –protect public utility infrastructure (i.e., sanitary sewer and water distribution) 3.Maintain traffic flow through CR21 corridor 4.Maintain access to private properties Flood Response Policy Stormwater Management and Flood Mitigation Study (2016) Implementation: •Implementation plan recommends two short-term implementation options •City Flood Response Policy •PLSLWD Prior Lake Outlet, Active Management •Long-term implementation recommendation is to provide upper watershed storage Flood Response Policy Flood Response Policy Development •Reviewed lessons learned from the 2014 flood •Solicited comments from Public Works, Police, and Fire •2017 Trial Run! Flood Response Policy Flood Response Policy Elements •Defines areas of responsibility •Provides clear direction for coordinated response and communications during flooding events •Outlines a transition to our existing Emergency Operations Plan framework •Includes information on event tracking and cleanup efforts •Flood Watch Area maps Flood Response Policy Flood Response Policy Flood Response Policy 2017 Flood Response Trial Run •2016 was exceptionally wet (Twin Cities-area annual record) •Storage areas and soil had little capacity for additional precipitation heading into 2017 •Lakes began to respond to rains in mid-May •Spring Lake increased from ~911.0 to ~912.3 from May 15 to May 24 •Prior Lake increased from ~902.7 to ~903.5 from May 15 to May 31 Flood Response Policy 2017 Flood Response Trial Run Category Action Shoreline Erosion Prepare to deploy “Save Our Shores” signs at DNR public access points. Equipment Find a source of pumps and storm sewer plugs, various sizes & configurations; take inventory of sanitary manhole sealing devices; prepare to protect sanitary sewer lift stations; prepare to protect infrastructure at higher lake levels. Residential Sandbagging No action required at this level. City Emergency Operations Plan (EOP) No action required at this level. Mayor/City Council No action required at this level. Agency Coordination Contact PLSLWD staff and initiate communications regarding lake levels and Prior Lake Outlet Channel inspections and operation. Contact Spring Lake Township staff and initiate communications regarding lake levels. Infrastructure Protection No action required at this level. Water Quality Continue standard weekly surface water E. coli testing at public beaches (Sand Point and Watzl’s). Water Surface Use Management Prepare to deploy “Save Our Shores” signs at DNR public access points. Communications Initiate flood communications plan; monitor weather and lake levels; begin posting updates on website and social media. Prior Lake, 903.0 Elevation, Example Elevation-Based Flood Response Flood Response Policy 2017 Flood Response Trial Run Spring Lake, 911.9 Elevation, Example Elevation-Based Flood Response Category Action Shoreline Erosion Prepare to deploy “Save Our Shores” sign at public access point. Equipment N/A (no public infrastructure is threatened by high levels on Spring Lake) Residential Sandbagging No action required at this level. City Emergency Operations Plan (EOP) No action required at this level. Mayor/City Council No action required at this level. Agency Coordination Contact PLSLWD staff and initiate communications regarding lake levels and Prior Lake Outlet Channel operation. Contact Spring Lake Township staff and initiate communications regarding lake levels. Infrastructure Protection N/A (no public infrastructure is threatened by high levels on Spring Lake) Water Quality N/A (no public beaches or infrastructure is threatened by high levels on Spring Lake) Water Surface Use Management Prepare to deploy “Save Our Shores” sign at public access point. Communications Initiate flood communications plan; monitor weather and lake levels; begin posting updates on website and social media. Flood Response Policy 2017 Flood Response Trial Run •2017 Actions Taken •Based on 903.0 and 903.5 response levels for Prior Lake and 911.9 and 912.3 response levels for Spring Lake •Monitored lake levels and coordinated with internal staff •Updated City website with current information •Coordinated with PLSLWD, Spring Lake Township, MN DNR, Scott County Sheriff’s Office Flood Response Policy 2017 Flood Response Trial Run •2017 Actions Taken •Located sources of storm sewer plugs, manhole cover seals, pumps, and road barriers •Verified sandbag supply •Secured sand donation from local source •“Save our Shores” signs deployed at Spring Lake and Prior Lake public launch sites Flood Response Policy Flood Response Plan Summary •Policy defines responsibilities & guides coordinated flood response •Elevation-based flood response plan for Spring & Prior Lakes •Transition to Emergency Management structure with declaration of Local Emergency Flood Response Policy Thank you! Pete Young, PE, CPESC Water Resources Engineer pyoung@cityofpriorlake.com