May 2013 Floodplain Management Training Course for the Ohio Department of Transportation Presented by Shawn Arden, PE, CFM ms consultants, inc.
May 2013 About the Instructor Shawn Arden, PE, CFM Water Resources Manager - ms consultants Professional Engineer Certified Floodplain Manager - Association of State Floodplain Managers Past-President - Ohio Floodplain Management Association
May 2013 Agenda Floodplain Management (FM) Background FM Considerations for Transportation Projects Floodplain Coordination Navigating a Project through FM Regulations Case Study Lessons Learned
May 2013 Goals Participants will learn: Floodplain management principles commonly associated with transportation projects How to identify floodplain management issues that will affect project programming
May 2013 Goals This course will not include: How to perform a hydraulic analysis
May 2013 Definitions 100-Year Flood – A flood that has a 1% annual chance of occurrence (i.e. in a single year) Floodplain – An area inundated by flood waters Floodway – A portion of the floodplain designated by FEMA as critical for flood flow conveyance. Fill in this area triggers no-rise performance standards
May 2013 Definitions
May 2013 Why is Floodplain Management Important? Reduce flood risk: Property damage Loss of life Economic damage
May 2013 Why is Floodplain Management Important? Maintain natural beneficial functions of the floodplain: Flood storage / attenuation Aquatic habitat Water quality
May 2013 Floodplain Management Background
May 2013 Floodplain Management Background Origination in United States Implementation of National Flood Insurance Program (NFIP) Floodplain Management Roles of Various Agencies Regulated vs. Unregulated Floodplains
May 2013 Origination in United States Gilbert White Published Human Adjustment to Floods “Floods are 'acts of God,' but flood losses are largely acts of man.”
May 2013 Implementation of NFIP Authorized by Congress under National Flood Insurance Act of 1968 NFIP is managed by the Federal Emergency Management Agency (FEMA)
May 2013 Implementation of NFIP Communities must enroll in NFIP for property owners to be eligible to purchase flood insurance from the government Communities must adopt floodplain development regulations as a condition of enrollment in the NFIP (created NFIP Development Permit)
May 2013 Implementation of NFIP Flood Disaster Protection Act of 1973 requires mandatory purchase of flood insurance for properties within the floodplain NFIP was intended to be self-sustaining
May 2013 Floodplain Management Roles of Agencies Local Communities
May 2013 Floodplain Management Roles of Agencies Administers NFIP Develops and issues flood insurance rate maps and flood insurance studies Audits community NFIP enrollment obligations
May 2013 Floodplain Management Roles of Agencies
May 2013 Floodplain Management Roles of Agencies
May 2013 Floodplain Management Roles of Agencies
May 2013 Floodplain Management Roles of Agencies Division of Soil & Water Resources Floodplain Management Program Serves as state NFIP coordinator Performs community audits on behalf of FEMA Acts as state resource for FM data and policy
May 2013 Floodplain Management Roles of Agencies Division of Soil & Water Resources Floodplain Management Program Does not issue permits
May 2013 Floodplain Management Roles of Agencies Enroll in NFIP Adopt and enforce floodplain (NFIP) development regulations Review NFIP permit applications and issue permits Maintain FIRM panels Local Communities
May 2013 Floodplain Management Roles of Agencies Designs flood protection works Require evidence of NFIP Permit as condition of 401/404 Permit Limits floodplain impacts under NPDES permits
May 2013 Floodplain Management Roles of Agencies NFIP Permit Applicant
May 2013 Regulated vs. Unregulated Floodplains FEMA has identified minimum floodplain development standards for community participation in the NFIP. Standards are tied to the 100-year (1% annual chance) flood event as identified by FEMA Regardless if FEMA has identified a 100-year inundation area, all drainage courses overtop their banks from time to time
May 2013 Regulated vs. Unregulated Floodplains Is the floodplain for this river regulated by FEMA? Will this river overtop its banks?
May 2013 Floodplain Management Background
May 2013 Floodplain Management Considerations for Transportation Projects
May 2013 FM Considerations for Transportation Projects NFIP Minimum Design Standards ODOT L&D Manual, Volume 2 Additional Local Design Standards Engineering Best Practices
May 2013 NFIP Minimum Design Standards Title 44 CFR 60.3 – See Appendix No Rise Definition: 0.00 ft
May 2013 ODOT L&D Manual Section 1005 discusses highway encroach- ments on floodplains (see appendix) Designs shall permit conveyance of 100-year discharge without causing significant damage to the highway, the watercourse, or other property
May 2013 Additional Local Design Standards Be aware that communities can adopt more stringent floodplain development standards Freeboard No rise in all areas No fill Etc.
May 2013 Engineering Best Practices No adverse impact Minimize fill placement within the river channel
May 2013 FM Considerations for Transportation Projects
May 2013 Floodplain Coordination
May 2013 Floodplain Coordination Pre-Application Meeting Permit Submittal Post-Permit Issuance Requirements
May 2013 Pre-Application Meeting Per L&D Manual Section , confirm allowable headwater and permitting requirements with local community early in the design process (Floodplain Coordination) For complex projects, request key decision makers from the local community attend the pre-application meeting
May 2013 Permit Submittal Submittal will consist of: Community specific permit application Design plans* Hydraulic analysis (if required)* CLOMR application (if required)* No rise certification (if required; see appendix)* *Requires Professional Engineer Seal
May 2013 Permit Submittal Important Note: If a CLOMR is required, the community cannot issue the NFIP permit until FEMA reviews and approves the CLOMR application. Depending on project complexity, obtaining FEMA approval of a CLOMR can take up to 12 months!
May 2013 Permit Submittal Community may also require: Permit and hydraulic analysis review fees Storm Water Pollution Prevention Plan (SWP3) Conservation easements Review can require 1-4 weeks depending on the community and project scope
May 2013 Post-Permit Issuance Requirements NFIP Development Permits may be issued with conditions that must be followed upon issuance: Expiration date (typically 6 or 12 months) Letter of Map Revision As-built survey documentation
May 2013 Floodplain Coordination
May 2013 Navigating a Project through Floodplain Management Regulations
May 2013 Navigating a Project through Floodplain Management Regulations Identifying Existing Conditions Hydrologic and Hydraulic Analyses Interpreting Post-Project Results Advanced Topics
May 2013 Identifying Existing Conditions Interpreting a FEMA Flood Insurance Rate Map Interpreting a FEMA Flood Insurance Study Using FEMA Digital FIRM (D-FIRM) Information Local Community Engagement
May 2013 Identifying Existing Conditions Interpreting a FEMA Flood Insurance Rate Map Appendix 4
May 2013 Identifying Existing Conditions Interpreting a FEMA Flood Insurance Study Appendix 5
May 2013 Identifying Existing Conditions Using FEMA Digital FIRM (D-FIRM) Information
May 2013 Identifying Existing Conditions Local Community Engagement County Engineer and Local Floodplain Administrator can assist in identifying unmapped flood-prone areas
May 2013 Hydrologic and Hydraulic Analyses When are they required? Who can prepare? Who reviews? What software / methods are acceptable? Notes on requesting data from FEMA
May 2013 Hydrologic and Hydraulic Analyses When are H&H analyses required for floodplain permitting? When placing fill within a floodway When requested by the local community
May 2013 Hydrologic and Hydraulic Analyses Who can prepare? The hydraulic analysis must be sealed by a Professional Engineer
May 2013 Hydrologic and Hydraulic Analyses Who reviews? Local community (or their consultant)
May 2013 Hydrologic and Hydraulic Analyses What software / methods are acceptable? Hydrology: Rational Method, Unit Hydrograph Method, Regression Equations, Stream Gage Analysis Hydraulics: Standard step backwater analysis
May 2013 Hydrologic and Hydraulic Analyses What software / methods are acceptable? FEMA Approved Software “Numerical Models Meeting the Minimum Requirement of the NFIP”
May 2013 Hydrologic and Hydraulic Analyses Notes on requesting data from FEMA Budget 6 weeks and $500 for data request Many older models have been archived on microfiche FEMA will typically provide a paper print of the microfiche for the WSP-2 or HEC-2 hydraulic model input file
May 2013 Hydrologic and Hydraulic Analyses Notes on requesting data from FEMA Data request form is on FEMA’s website
May 2013 Interpreting Post-Project Results Compare Pre-Project and Post-Project peak water surface elevations at common points along the watercourse (river stations) Identify peak water surface elevation increase Compare peak increase to maximum allowable increase from local community development regulations
May 2013 Interpreting Post-Project Results
May 2013 Advanced Topics Conditional Letters of Map Revision (CLOMR) and Letters of Map Revision (LOMR) Parallel Bridges (Divided Highway Scenario) Temporary Fill (Causeways) Common Additional Local Standards
May 2013 CLOMR’s and LOMR’s CLOMR – Conditional Letter of Map Revision LOMR – Letter of Map Revision
May 2013 CLOMR’s and LOMR’s CLOMR – Conditional Letter of Map Revision Letter from FEMA stating proposed project, if built per plan, is in compliance with NFIP requirements Does not revise flood maps
May 2013 CLOMR’s and LOMR’s LOMR – Letter of Map Revision Revises flood maps and effective flood elevations Based on as-built information
May 2013 CLOMR’s and LOMR’s Submittal Requirements: Application forms Application fee (currently up to $5,300) Hydraulic analysis Proof of public notice Proof of no impacts to insurable structures* *No impact = 0.0 ft, or mitigate impact
May 2013 CLOMR’s and LOMR’s Submittal Requirements: Proof of compliance with threatened and endangered species requirements Community signature Construction plans
May 2013 CLOMR’s and LOMR’s Tips and Tricks: Processing can require months CLOMR application can be based on “conceptual data” at applicant’s risk Have FEMA approve hydraulic analysis prior to performing public notice activities
May 2013 Parallel Bridges
May 2013 Parallel Bridges Parallel bridges can typically be analyzed as a single hydraulic structure Widening to the inside of the bridges will typically not affect the hydraulic performance (i.e. no rise condition) Refer to HDS-1 for more information
May 2013 Temporary Fill Temporary fill is often required to construct causeways for bridge projects Temporary fill is not specifically addressed in the NFIP… …and is typically not required to be a part of the NFIP permit
May 2013 Common Additional Local Standards Freeboard Compensatory Storage Future Conditions Analysis Mandatory LOMR
May 2013 Freeboard Freeboard is a minimum amount of clearance between the high water elevation and bridge low chord
May 2013 Compensatory Storage Compensatory storage requires the volume of fill placed in the floodplain to be offset by an equal or greater volume of excavation Goal is to maintain available flood plain storage volume available to attenuate streamflow Franklin County, Medina County, Columbus
May 2013 Compensatory Storage Compensatory storage requirements can be difficult to satisfy on linear transportation projects due to limited right-of-way. Linear transportation projects are sometimes exempt from this requirement; verify with each local community
May 2013 Future Conditions Analysis Future conditions analysis requires a project to be analyzed against existing and future flood discharge rates Currently used in Licking County
May 2013 Mandatory LOMR Some communities require a LOMR for all development in the floodplain as a means to keep their flood maps up to date Requirement should be discovered during Floodplain Coordination effort Be aware of any budget or schedule implications this may have on your project
May 2013 Navigating a Project Through Floodplain Management Regulations
May 2013 Case Study
May 2013 Lessons Learned
May 2013 Lessons Learned Pre-application meetings are invaluable Make sure local community’s decision makers are present for complex projects
May 2013 Lessons Learned Avoid the CLOMR/LOMR process if possible Adds to the project cost Adds to the project schedule Strict notification process
May 2013 Lessons Learned Make sure the proposed plan makes sense May appear to be obvious Hydraulic analyses are not an exact science Sometimes a minimal flood profile rise can be justified…
May 2013 Upcoming Conferences 2013 Ohio Floodplain Management Conference August 28-29, 2013 – Columbus for more information
May 2013 QUESTIONS Shawn Arden, PE, CFM ms consultants, inc Schrock Road Columbus, Ohio,