All projects in floodways must be evaluated for their potential impacts to flood heights. Projects in Federal Emergency Management Agency (FEMA) Floodways must demonstrate that they will not increase flood heights (No-rise) or must proceed through the appropriate FEMA process to document the increase in flood heights (surcharge) and revise the floodplain mapping. Projects taking place in FEMA Floodways are required to obtain either a No-rise Certification or apply for and obtain a Conditional Letter of Map Revision (CLOMR) before construction and a Letter of Map Revision (LOMR) post-construction. No-rise requirements are linked to local community participation in the National Flood Insurance Program (NFIP). To participate in the NFIP, local communities must adopt floodplain regulations based on federal code that that meet minimum standards set forth by FEMA. No-rise requirements come from 44 CFR 60.3 (d) (3).
44 CFR 60.3 (d) (3) Prohibit encroachments, including fill, new construction, substantial improvements, and other development within the adopted regulatory floodway unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practice that the proposed encroachment would not result in any increase in flood levels within the community during the occurrence of the base flood discharge.
FAQs
- What has changed regarding projects in FEMA Floodways?
- I have heard that FEMA will no longer allow DNR to have up to a 0.14’ surcharge without a LOMR.
- When does my project need No-rise Certification?
- Why does my project need a CLOMR?
- Does this mean that I cannot use DNR’s Non-modeling worksheets?
- What happens if I do not get my No-rise Certification or CLOMR?