D.C. Mun. Regs. tit. 12, app 12-A-G r. 12-A-G103
Permit applications. The code official shall review all permit applications to determine whether the proposed development is located on a development site that is wholly or partially within flood hazard areas established in Section G102.2. Where a proposed development site is located wholly or partially within a flood hazard area, all development to which this appendix is applicable as specified in Section G102.1 shall be designed and constructed with methods, practices and materials that minimize flood damage and that are in accordance with the Construction Codes and ASCE 24.
Determinations of Substantial Improvement and Substantial Damage. For applications for reconstruction, rehabilitation, repair, alteration, addition or other improvement of existing buildings or structures located in flood hazard areas, the code official, in coordination with the Floodplain Administrator, shall determine if the proposed work constitutes substantial improvement or repair of substantial damage. Where the code official determines that the proposed work constitutes substantial improvement or repair of substantial damage, and where required by the Construction Codes, the code official shall require the building or structure to meet the flood resistant construction requirements of the Construction Codes as applicable. The code official's determinations of substantial damage and substantial improvement shall be subject to review by the Floodplain Administrator, and receipt of recommendations and comments from the Floodplain Administrator regarding disposition of the application by the code official.
Authority to Request Data. The code official shall have authority to request submission by a permit applicant of any information or documentation that the code official deems necessary to make a determination of substantial improvement and substantial damage, including but not limited to estimates of the improvement or repair costs pursuant to the methodology set forth in the Substantial Improvement/Substantial Damage Desk Reference.
Determination of design flood elevations.Design flood elevations shall be reviewed and approved by the Floodplain Administrator in accordance with 20 DCMR. If design flood elevations are not specified on the FIRM, the code official is authorized to require the applicant to:
Activities in riverine flood hazard areas. In riverine flood hazard areas where design flood elevations are specified but floodways have not been designated, the code official shall no t permit any new construction, substantial improvement or other development, including fill, on a development site, unless the applicant (a) submits an engineering analysis prepared by a registered design professional in accordance with Section 1612.3.2; and (b) such analysis is reviewed and approved by the Floodplain Administrator pursuant to 20 DCMR Chapter 31.
Floodway encroachment. Prior to issuing a permit for any floodway encroachment, including fill, new construction, substantial improvements and other development or land-disturbing activity, the applicant shall submit a "no-rise" certification, prepared by a registered design professional, along with supporting technical data, demonstrating that such development will not cause any increase of the base flood level. The code official shall refer the certification to the Floodplain Administrator for review and approval before issuing a permit for any floodway encroachment.
Watercourse alteration. Authorization to alter or relocate any watercourse shall be obtained from the Floodplain Administrator pursuant to 20 DCMR Chapter 31.
Review and Consultation by Floodplain Administrator. No permit application within the scope of this appendix and the flood-resistant construction provisions of the Construction Codes shall be granted without review by the Floodplain Administrator. The Floodplain Administrator shall review applications and make recommendations to the code official pursuant to his or her responsibilities as set forth in 20 DCMR Chapter 31.
Coordination of Duties. The code official and the Floodplain Administrator shall coordinate duties and responsibilities relating to development on a development site located wholly or partially within a flood hazard area as necessary to achieve compliance with the requirements of the National Flood Insurance Program for District of Columbia participation (Title 44 CFR, Section 59.22) , and to streamline the permitting and inspection process for such development, consistent with this appendix.
Records. The code official shall retain for a duration no less than that specified in accordance with NFIP requirements the following records related to development on a development site wholly or partially within a flood hazard area: all permits issued, subdivision applications/approvals, modifications of the Construction Codes or variances of the Flood Hazard Rule; final inspection approvals and certificates of occupancy upon project completion. The Floodplain Administrator shall retain for a duration no less than that specified in accordance with NFIP requirements: records of FIRMs, FIS, Letters of Map Amendment, Letters of Map Revision; elevation certificates and floodproofing certificates, and records of any other documentation required by the Flood Hazard Rules not delegated to the code official for recordkeeping.
D.C. Mun. Regs. tit. 12, app 12-A-G r. 12-A-G103