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COMPREHENSIVE FLOODPLAIN MANAGEMENT : Promoting Wise Uses of Floodplains CA Department of Water Resources/ CIFMCG Workshop July 2006
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Comprehensive Floodplain Management Workshop No Adverse Impact Strategies
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Workshop Modules Comprehensive FPM Comprehensive FPM NFIP Overview NFIP Overview FPM No Adverse Impact Strategies FPM No Adverse Impact Strategies Natural Floodplain Functions and Societal Values Natural Floodplain Functions and Societal Values Flood Management Economic Analysis Ecosystem Evaluation Methods Flood Management Economic Analysis Ecosystem Evaluation Methods Case Study Case Study Technical and Financial Assistance Technical and Financial Assistance
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No Adverse Impact Background Background Strategies Strategies Overcoming Legal Barriers Overcoming Legal Barriers
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No Adverse Impact Background Background NAI Strategies NAI Strategies Overcoming Legal Barriers Overcoming Legal Barriers
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NAI Background NAI is being proposed by the ASFPM to: NAI is being proposed by the ASFPM to: Ensure the actions of any community or property owner do not adversely impact others Incorporate multi-objective and watershed planning principles NAI doesn’t mean “no development” NAI doesn’t mean “no development” NAI means that any adverse impact caused by a project must be mitigated, preferably based on a community or watershed-based plan NAI means that any adverse impact caused by a project must be mitigated, preferably based on a community or watershed-based plan
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NAI Background Types of adverse impacts: Types of adverse impacts: Increased flood stages, velocities, flows Increased potential for erosion and sedimentation Increased cost of public services Degradation of water quality Impacts may occur anywhere in the watershed Impacts may occur anywhere in the watershed
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NAI Background Benefits of NAI: Benefits of NAI: Reduce flood losses over time in your community Reduce likelihood of your actions increasing flood damage to others Reduce challenges and lawsuits Receive recognition through the Community Rating System Incorporate multiple objectives Protect natural resources and values of floodplains
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No Adverse Impact Background Background NAI Strategies NAI Strategies Overcoming Legal Barriers Overcoming Legal Barriers
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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NAI Strategies Strategies grouped according to: Strategies grouped according to: Basic Better NAI Source: ASFPM, No Adverse Impact: A Toolkit for Common Sense Floodplain Management (2003) www.floods.org/NoAdverseImpact/NAI_Toolkit_2003.pdf
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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Hazard Identification Basic Strategies Join NFIP Join NFIP FIS Study Flood Insurance Rate Map Adopt FPM ordinance Maintain FIRM and enforce FPM ordinance Maintain FIRM and enforce FPM ordinance
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Hazard Identification Better Strategies Strengthen Approximate A Zone requirements Strengthen Approximate A Zone requirements NFIP only requires detailed data if development is larger than 5 acres or 50 lots Require developers provide detailed flood data for all developments Develop better base map for FIRM Develop better base map for FIRM Smaller contour intervals Include more recent land use information Include local coastal program boundaries on FIRM Include local coastal program boundaries on FIRMwww.coastal.ca.gov/lcps.html
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Hazard Identification Better Strategies Map other flood related hazards Map other flood related hazards Uncertain flow paths Closed/restricted outflow basin lakes Debris and sediment blockage Land subsidence Mudflows Dam failure inundation Tsunamis Coastal and riverine erosion
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Hazard Identification NAI Strategies Use future conditions hydrology to develop maps Use future conditions hydrology to develop maps Flood discharges based upon projected land use changes Future condition floodplains can be shown on FIRMs for “informational” purposes
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Hazard Identification NAI Strategies Adopt higher floodway mapping standards Adopt higher floodway mapping standards Assume entire floodplain is a floodway Assume entire floodplain is a floodway Floodway standards are in effect across entire floodplain Development cannot cause any increase in BFE which might affect others
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Hazard Identification NAI Strategies Require no loss of storage or velocity increases Require no loss of storage or velocity increases Communities can require that floodway delineation be based on preventing a loss of storage and/or increase in velocity Example: Illinois requires floodways to be mapped using a 0.1 ft allowable rise, and a maximum 10% increase in velocity with a maximum 10% loss of floodplain storage
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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Education & Outreach Basic Strategies Make documents and maps available to the public Make documents and maps available to the public FISs/FIRMs Permit records Have staff available to answer questions Have staff available to answer questions Is my property in the floodplain? What is the base flood elevation? What development regulations apply to me? Where do I go for flood insurance?
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Education & Outreach Better Strategies Implement risk communication program Implement risk communication program Advise residents and businesses of flood hazards Provide information as to what is being done Provide information on how residents can protect themselves Use different tactics (ex: websites, utility bill leaflets, etc.)
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Education & Outreach Sacramento Hypothetical Flood Maps www.cityofsacramento.org/utilities/flood/Sacramento_Flood_Maps.html
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Education & Outreach Sacramento Evacuation Maps www.cityofsacramento.org/utilities/flood/Sacramento_Flood_Maps.html
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Education & Outreach Better Strategies Show additional information Show additional information Aerial photos of buildings superimposed on FIRMs Show additional hazards (alluvial fans, mudflows) Show possible flooding outside of mapped areas
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Education & Outreach Better Strategies Implement outreach programs Implement outreach programs Brochures/displays in public places Newspaper articles Utility bill inserts Flood protection videos Neighborhood presentations Floodplain signs Websites (ex: www.city.palo-alto.ca.us/cgi-bin/floods.cgi )
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Education & Outreach NAI Strategies Educate staff, decision makers and the public Educate staff, decision makers and the public FEMA/State/ASFPM NFIP workshops and courses Certified Floodplain Manager Program Distribute NAI brochures, posters and videos Develop models or presentations Develop school environmental and safety education programs
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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Planning Basic Strategies Prepare comprehensive land use plans Prepare comprehensive land use plans Identify hazard areas Identify appropriate land uses Develop special subject plans to supplement comprehensive plans Develop special subject plans to supplement comprehensive plans Economic development plan Habitat protection plan Watershed management plan Adopt zoning or other ordinances to enforce plans Adopt zoning or other ordinances to enforce plans
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Planning Better Strategies Identify flood-risk areas on plans and restrict development Identify flood-risk areas on plans and restrict development Adopt low-density zoning in floodplains Adopt low-density zoning in floodplains Use specialized tools (ex: GIS, HAZUS, HEC-FDA, etc.) Use specialized tools (ex: GIS, HAZUS, HEC-FDA, etc.) Prepare FPM, storm water management and special area plans to supplement comprehensive plans Prepare FPM, storm water management and special area plans to supplement comprehensive plans Prepare multi-hazard mitigation plans Prepare multi-hazard mitigation plans
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Planning Better Strategies Floodplain Management Plans Floodplain Management Plans Identify flood prone/repetitive loss areas Evaluate various flood damage reduction measures Recommend actions for the community Identify mapping needs Multi-Hazard Management Plans Multi-Hazard Management Plans Identify all natural hazard areas Evaluate various hazard mitigation measures Recommend actions for the community
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Planning NAI Strategies Include watershed, MOM and sustainable development principles in land use planning Include watershed, MOM and sustainable development principles in land use planning Consider current and future development Coordinate floodplain planning with other planning activities (economic development, housing, recreation, ecosystem restoration, water quality, etc.) Identify long-term implications of alternative land uses Promote “sustainable” development
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Planning NAI Strategies Sustainable development is “…meeting the needs of the present without compromising the ability of future generations to meet their own needs.” (ASFPM, NAI Toolkit)
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Planning NAI Strategies Governor’s Office of Planning and Research has incorporated floodplain management into its General Plan Guidelines as an “optional” element Governor’s Office of Planning and Research has incorporated floodplain management into its General Plan Guidelines as an “optional” elementwww.opr.ca.gov/planning/PlanningPubs.html
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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Regulation & Development Standards Basic Strategies Adopt separate FPM ordinance with minimum FPM regulations Adopt separate FPM ordinance with minimum FPM regulations NFIP estimates that buildings built to minimum standards suffer 70% less than unprotected buildings NFIP estimates that buildings built to minimum standards suffer 70% less than unprotected buildings Flood damage can still occur with minimum standards Flood damage can still occur with minimum standards BFEs subject to change, particularly as development occurs in watershed BFEs subject to change, particularly as development occurs in watershed
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Regulation & Development Standards Basic Strategies Example minimum FPM regulations Example minimum FPM regulations All development in 100-yr floodplain must have a permit Development in floodway must not cause increase in base flood levels New residential buildings in riverine floodplains must have top of lowest floor elevated above BFE New non-residential buildings in riverine floodplains must have top of lowest floor elevated to the BFE or flood proofed 1 foot above BFE Substantially improved buildings (costs exceeding 50% of market value) are considered “new” buildings
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Regulation & Development Standards Better Strategies Adopt NFIP regulations with higher standards Adopt NFIP regulations with higher standards Receive Community Rating System Credit for higher standards and lower insurance premiums for your community Receive Community Rating System Credit for higher standards and lower insurance premiums for your community CA Model Ordinance: CA Model Ordinance:www.fpm.water.ca.gov/ordinance/Ordinance01.doc
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Regulation & Development Standards Better Strategies Require additional height requirement above BFE (“freeboard”) Require additional height requirement above BFE (“freeboard”) Accounts for rise in BFE due to development in floodplain and the watershed Accounts for uncertainties inherent in flood modeling Results in significantly lower flood insurance rates (almost a 50% reduction in building and contents rates by adding one foot of freeboard) Most common higher regulatory standard adopted by states and communities
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Regulation & Development Standards Better Strategies Strengthen “substantially improved” building requirements Strengthen “substantially improved” building requirements For each structure, count substantial improvements cumulatively rather than individually to reach 50% threshold Lower 50% threshold value All additions outside original building footprint must meet building protection standards
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Regulation & Development Standards Better Strategies Flood fringe development Flood fringe development Require buildings to be built on columns, not fill If buildings built on fill, require compensatory storage (ex: storage equal to1.5 or 2 times amount of fill) Adopt International Building Codes which include flood reduction standards Adopt International Building Codes which include flood reduction standards Adopt subdivision standards that require structures to be built outside of hazard areas Adopt subdivision standards that require structures to be built outside of hazard areas
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Regulation & Development Standards Better Strategies Utilize “green infrastructure” Utilize “green infrastructure” Green space includes large metro and neighborhood parks, riparian buffers, linear parks and greenbelts Green space is used as infrastructure just like roads, water lines and sewers Green space provides services that are useful to humans, such as storm water storage and conveyance Include green space to avoid more costly structural solutions www.greeninfrastructure.net/
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Regulation & Development Standards Better Strategies Adopt storm water regulations Adopt storm water regulations Require developers to include detention basins Require less impervious materials Slow surface runoff using terraces, contour strip farming, sediment fences, hay or straw bales, etc. Develop erosion and sediment control models Adopt higher health and safety standards Adopt higher health and safety standards Keep septic systems and landfills out of floodplains Restrict hazardous materials in floodplains (exs: gasoline, pesticides and chemicals)
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Regulation & Development Standards NAI Strategies Preserve beneficial natural floodplain functions Preserve beneficial natural floodplain functions Adopt setback standards to establish minimum distances from river channels or shorelines Adopt buffer zone requirements between sensitive and developed areas Adopt proactive developer requirements Implement stream restoration programs
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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Mitigation Basic Strategies Implement structural flood management measures Implement structural flood management measures Reservoirs Levees Channel modifications Dredging By-passes Make flood insurance available Make flood insurance available
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Mitigation Better Strategies Implement non-structural flood management measures Implement non-structural flood management measures Enforcement of community rules, regulations and procedures Dry and wet flood proofing Building elevation Building relocation Building acquisition/demolition
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Mitigation NAI Strategies Implement master flood planning (ex: integrate watershed, storm water, habitat protection and FPM planning efforts) Implement master flood planning (ex: integrate watershed, storm water, habitat protection and FPM planning efforts) Involve all stakeholders in planning process Involve all stakeholders in planning process Mitigate while not transferring flood problems elsewhere Mitigate while not transferring flood problems elsewhere
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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Infrastructure Basic Strategies Minimal flood planning Minimal flood planning Respond to events as they happen Respond to events as they happen Repair or replace damaged facilities with similar facilities Repair or replace damaged facilities with similar facilities
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Infrastructure Better Strategies Inventory flood-prone facilities Inventory flood-prone facilities Take actions to protect flood-prone facilities Take actions to protect flood-prone facilities Set protection standards for new facilities Set protection standards for new facilities Obtain flood insurance Obtain flood insurance Develop emergency action plans Develop emergency action plans
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Infrastructure NAI Strategies Coordinate capital improvement plans with FPM plans Coordinate capital improvement plans with FPM plans Set higher regulatory standards for critical facilities (ex: protect facilities from 500-yr event) Set higher regulatory standards for critical facilities (ex: protect facilities from 500-yr event) Use “green infrastructure” to reduce maintenance costs and achieve other benefits Use “green infrastructure” to reduce maintenance costs and achieve other benefits
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NAI Strategies Hazard identification Hazard identification Education and outreach Education and outreach Planning Planning Regulations and development standards Regulations and development standards Mitigation Mitigation Infrastructure Infrastructure Emergency services Emergency services
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Emergency Services Basic Strategies Prepare generic emergency response plan based upon off-the-shelf “model” plans Prepare generic emergency response plan based upon off-the-shelf “model” plans Plans may not meet needs of specific communities Plans may not meet needs of specific communities
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Emergency Services Better Strategies Prepare flood preparedness plans Prepare flood preparedness plans Prepare flood stage forecast maps Prepare flood stage forecast maps Prepare dam/levee failure emergency action plans Prepare dam/levee failure emergency action plans Implement flood warning systems Implement flood warning systems Identify flood response actions and responsible parties Identify flood response actions and responsible parties
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Emergency Services NAI Strategies Improve pre- and post disaster preparedness and procedures (ex: improve methods to evaluate damaged buildings) Improve pre- and post disaster preparedness and procedures (ex: improve methods to evaluate damaged buildings) Apply for pre- and post disaster mitigation funds Apply for pre- and post disaster mitigation funds Incorporate MOM/sustainability principles into post-disaster plans and actions Incorporate MOM/sustainability principles into post-disaster plans and actions
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No Adverse Impact Background Background NAI Strategies NAI Strategies Overcoming Legal Barriers Overcoming Legal Barriers
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Overcoming Legal Barriers ASFPM is researching common FPM case law questions: ASFPM is researching common FPM case law questions:
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Overcoming Legal Barriers When are public agencies most likely to be held liable for increasing flood or erosion damage on private lands? By… When are public agencies most likely to be held liable for increasing flood or erosion damage on private lands? By… Blocking natural drainage because of grading, fill, or structures (bridges, culverts, etc.) Increasing the location and amount of runoff because of channelization or other drainage projects Constructing flood control works such as levees and dams Inadequately maintaining flood control and related structures Performing inadequate inspections Approving development that increases flood damage on other lands
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Overcoming Legal Barriers Have courts upheld the overall constitutionality of state and local floodplain regulations? Have courts upheld the overall constitutionality of state and local floodplain regulations? Yes; courts at all levels have broadly and repeatedly upheld the validity of FPM regulations in the last 15 years What have been the most common challenges to FPM regulations in the last 15 years? What have been the most common challenges to FPM regulations in the last 15 years? Regulators permitted construction that later caused damage Unconstitutional over-regulation, or “taking”, of property without payment of just compensation
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Overcoming Legal Barriers May a local government adopt floodplain regulations that exceed State or Federal (NFIP) minimum standards? May a local government adopt floodplain regulations that exceed State or Federal (NFIP) minimum standards? Yes; local government regulations may exceed state or federal regulations NFIP regulations specifically encourage state and local regulations that exceed minimum federal standards
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Overcoming Legal Barriers How can a local government avoid successful legal challenges? How can a local government avoid successful legal challenges? Regulations must be based on principles of hazard prevention and “no adverse impact” to others Regulations must be applied fairly and uniformly Include exemption and variance provisions Allow some economic uses of the regulated land For floodplain areas, adopt large-lot zoning which permits some economic use on the upland portion of each lot Allow for the transfer of development rights from floodplain to non-floodplain parcels Fairly tax and levy assessments on economic uses which will be allowed
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To Summarize… ASFPM No Adverse Impact strategies: ASFPM No Adverse Impact strategies: Hazard identification Education and outreach Regulations and development standards Planning Mitigation Infrastructure Emergency services Strategies grouped by: Strategies grouped by: Basic Better No Adverse Impact Communities are encouraged to go beyond basic strategies Communities are encouraged to go beyond basic strategieswww.floods.org/NoAdverseImpact/NAI_Toolkit_2003.pdfwww.floods.org/NoAdverseImpact/whitepaper.asp
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What’s Next? Natural floodplain functions and societal values Natural floodplain functions and societal values
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