Rebuilding Stream Crossing In Infrastructure after Tropical Storm Ir Irene Rob ob Evans Riv ivers Program Manager VT De Department of of Envi vironmental Con Conservati tion
1.VT Context/Background 2.FEMA Public Assistance grants primer 3.Codes and Standards Debate
Mountainous Landscape
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Mountainous la landscape, & old ld stream crossing infrastructure… … and in increased fr frequency and magnitude of flo loods
Mountainous la landscape & old ld stream crossing infrastructure… … and more fl flooding
Federal Flo lood Declarations
Flood Recovery reimbursement program that covers permanent repair work to FEMA Public damaged or destroyed public infrastructure. Assis istance “….not an infrastructure improvement program .”
FEMA Public Assis istance
FEMA Public Structure is eligible for replacement if Repair cost > 50% of Replacement cost Assis istance Standard practice is in-kind repair/replacement Upsizing the structure eligible if it needs to meet codes and standards ; OR FEMA uses its discretionary “mitigation” authority to allow upsizing of the structure (case by case)
FEMA Publi lic Structure is eligible for replacement if Repair cost > 50% of Replacement cost Assis istance Standard practice is in-kind repair/replacement, Unless: Upsizing the structure eligible if it needs to meet codes and standards ; OR FEMA uses its discretionary “mitigation” authority to allow upsizing of the structure (case by case).
1. Applies to the type of restoration required; Public Assistance 2. Is appropriate to the pre-disaster use of the Codes & Standards facility; Criteria 3. Be Reasonable, in writing, formally adopted, and implemented prior to the disaster declaration; 4. Apply Uniformly to all Facilities of the type being repaired, i.e., they are Non- discretionary; and 5. Was enforced during the time it was in effect.
1. Applies to the type of restoration required; Public Assistance 2. Is appropriate to the pre-disaster use of the Codes & Standards facility; Criteria 3. Be Reasonable, in writing, formally adopted, and implemented prior to the disaster declaration; 4. Apply Uniformly to all Facilities of the type being repaired, i.e., they are Non- discretionary; and 5. Was enforced during the time it was in effect.
Be Reasonable, in writing, formally adopted, and implemented prior to the disaster 1. Formally Adopted in 2013 declaration 2. VT stream alteration standards are reasonable: • Scientifically based • Economically justified • Consistent with the intent of State law
Apply Rule contains hydro-geomorphic Uniformly and performance standards. be Non- Design requirements in dis iscretionary ry; consideration of sediment and debris transport, and fish passage: ▪ span length ▪ opening height ▪ depth of structure (embeddedness )
Traditional methods focus on Apply hydraulic sizing based on design flows (e.g. 25 or 50 year flood). Uniformly and be Non- dis iscretionary ry; 17
Key Principles Structure Width and Opening Height 18
Key Principles Structure Width and Opening Height Key Principles S Old – 7’ Pipe New – 16’ x 8’ Precast Arch
Key Principles Vertical alignment on Longitudinal Profile
Key Principles Vertical alignment on Longitudinal Profile Interruption of stream sediment/debris transport aggradation above and degradation below
Key Principles Vertical alignment on Longitudinal Profile Embeddedness requirements
Apply Uniformly FEMA questioned whether VT’s performance-based standards and be Non- allowed for too much discretion in dis iscretio ionary ry; their technical application. Vermont argued that bridges and culverts have been traditionally designed from codes using performance-based engineering standards;
The Stream Alteration Rule employs Apply Uniformly “equilibrium” and “connectivity” performance standards. and be Non- dis iscretio ionary ry; 15 USC § 205c (2) [Title 15. Commerce and Trade; Chapter 6: “engineering standard” means “a standard which prescribes (A) a concise set of conditions and requirements that must be satisfied by a material, product, process, procedure, convention, or test method; and (B) the physical, functional, performance and/or conformance characteristics thereof .”
Stream Alteration performance standards are Apply Uniformly not discretionary, and the engineering design process is contained in 3 complimentary and be Non- technical documents: dis iscretio ionary ry;
Amendments Key modifications: to VT Rule minimum span height, length, embeddedness standards; and General Needed explicit reference to the above Permit for Individual Permit requirements; Needed to add specific reference to the VTrans Hydraulics Manual; Needed us to include specific language from Dept of Fish and Wildlife Guidelines;
Formal FEMA Acceptance The revised mandatory nature of design requirements for replacement culverts and 2017 2017 bridges under the Rule and Permit appear to adequately address the previous concerns identified by FEMA that put in doubt the Rule and Permit would meet the requirements of 44 CFR…
Rob ob Evans Riv ivers Prog ogram Manager Ver ermont t DE DEC rob.evans@vermont.gov 802.4 .490.6152 Thank You!
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