COMPREHENSIVE FLOODPLAIN MANAGEMENT : Promoting Wise Uses of Floodplains

1. CA Department of Water Resources/ CIFMCG Workshop COMPREHENSIVE FLOODPLAIN MANAGEMENT: Promoting Wise Uses of Floodplains July 2006

2. Comprehensive Floodplain Management Workshop No Adverse Impact Strategies

3. Workshop Modules • Comprehensive FPM • NFIP Overview • FPM No Adverse Impact Strategies • Natural Floodplain Functions and Societal Values • Flood Management Economic AnalysisEcosystem Evaluation Methods • Case Study • Technical and Financial Assistance

4. No Adverse Impact • Background • Strategies • Overcoming Legal Barriers

5. No Adverse Impact • Background • NAI Strategies • Overcoming Legal Barriers

6. NAI Background • 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 means that any adverse impact caused by a project must be mitigated, preferably based on a community or watershed-based plan

7. NAI Background • 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

8. NAI Background • 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

9. No Adverse Impact • Background • NAI Strategies • Overcoming Legal Barriers

10. NAI Strategies • Hazard identification • Education and outreach • Planning • Regulations and development standards • Mitigation • Infrastructure • Emergency services

11. Strategies grouped according to: Basic Better NAI Source: ASFPM, No Adverse Impact: A Toolkit for Common Sense Floodplain Management (2003) NAI Strategies www.floods.org/NoAdverseImpact/NAI_Toolkit_2003.pdf

12. NAI Strategies • Hazard identification • Education and outreach • Planning • Regulations and development standards • Mitigation • Infrastructure • Emergency services

13. Hazard Identification Basic Strategies • Join NFIP • FIS Study • Flood Insurance Rate Map • Adopt FPM ordinance • Maintain FIRM and enforce FPM ordinance

14. Hazard IdentificationBetter Strategies • 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 • Smaller contour intervals • Include more recent land use information • Include local coastal program boundaries on FIRM www.coastal.ca.gov/lcps.html

15. Hazard IdentificationBetter Strategies • 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

16. Hazard IdentificationNAI Strategies • 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

17. Hazard IdentificationNAI Strategies • Adopt higher floodway mapping standards • 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

18. Hazard IdentificationNAI Strategies • 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

19. NAI Strategies • Hazard identification • Education and outreach • Planning • Regulations and development standards • Mitigation • Infrastructure • Emergency services

20. Education & OutreachBasic Strategies • Make documents and maps available to the public • FISs/FIRMs • Permit records • 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?

21. Education & OutreachBetter Strategies • 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.)

22. Education & OutreachSacramento Hypothetical Flood Maps www.cityofsacramento.org/utilities/flood/Sacramento_Flood_Maps.html

23. Education & OutreachSacramento Evacuation Maps www.cityofsacramento.org/utilities/flood/Sacramento_Flood_Maps.html

24. Education & OutreachBetter Strategies • Show additional information • Aerial photos of buildings superimposed on FIRMs • Show additional hazards (alluvial fans, mudflows) • Show possible flooding outside of mapped areas

25. Education & OutreachBetter Strategies • 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 )

26. Education & OutreachNAI Strategies • 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

27. NAI Strategies • Hazard identification • Education and outreach • Planning • Regulations and development standards • Mitigation • Infrastructure • Emergency services

28. PlanningBasic Strategies • Prepare comprehensive land use plans • Identify hazard areas • Identify appropriate land uses • 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

29. PlanningBetter Strategies • Identify flood-risk areas on plans and restrict development • Adopt low-density zoning in floodplains • Use specialized tools (ex: GIS, HAZUS, HEC-FDA, etc.) • Prepare FPM, storm water management and special area plans to supplement comprehensive plans • Prepare multi-hazard mitigation plans

30. Planning Better Strategies • 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 • Identify all natural hazard areas • Evaluate various hazard mitigation measures • Recommend actions for the community

31. PlanningNAI Strategies • 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

32. PlanningNAI 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)

33. PlanningNAI Strategies • Governor’s Office of Planning and Research has incorporated floodplain management into its General Plan Guidelines as an “optional” element www.opr.ca.gov/planning/PlanningPubs.html

34. NAI Strategies • Hazard identification • Education and outreach • Planning • Regulations and development standards • Mitigation • Infrastructure • Emergency services

35. Regulation & Development StandardsBasic Strategies • Adopt separate FPM ordinance with minimum FPM regulations • NFIP estimates that buildings built to minimum standards suffer 70% less than unprotected buildings • Flood damage can still occur with minimum standards • BFEs subject to change, particularly as development occurs in watershed

36. Regulation & Development StandardsBasic Strategies • 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

37. Regulation & Development StandardsBetter Strategies • Adopt NFIP regulations with higher standards • Receive Community Rating System Credit for higher standards and lower insurance premiums for your community • CA Model Ordinance: www.fpm.water.ca.gov/ordinance/Ordinance01.doc

38. Regulation & Development StandardsBetter Strategies • 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

39. Regulation & Development StandardsBetter Strategies • 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

40. Regulation & Development StandardsBetter Strategies • 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 subdivision standards that require structures to be built outside of hazard areas

41. Regulation & Development StandardsBetter Strategies • 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/

42. Regulation & Development StandardsBetter Strategies • 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 • Keep septic systems and landfills out of floodplains • Restrict hazardous materials in floodplains (exs: gasoline, pesticides and chemicals)

43. Regulation & Development StandardsNAI Strategies • 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

44. NAI Strategies • Hazard identification • Education and outreach • Planning • Regulations and development standards • Mitigation • Infrastructure • Emergency services

45. Mitigation Basic Strategies • Implement structural flood management measures • Reservoirs • Levees • Channel modifications • Dredging • By-passes • Make flood insurance available

46. Mitigation Better Strategies • 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

47. Mitigation NAI Strategies • Implement master flood planning (ex: integrate watershed, storm water, habitat protection and FPM planning efforts) • Involve all stakeholders in planning process • Mitigate while not transferring flood problems elsewhere

48. NAI Strategies • Hazard identification • Education and outreach • Planning • Regulations and development standards • Mitigation • Infrastructure • Emergency services

49. InfrastructureBasic Strategies • Minimal flood planning • Respond to events as they happen • Repair or replace damaged facilities with similar facilities

50. InfrastructureBetter Strategies • Inventory flood-prone facilities • Take actions to protect flood-prone facilities • Set protection standards for new facilities • Obtain flood insurance • Develop emergency action plans