ADOPTS WITH AMENDMENTS:

International Building Code 2015 (IBC 2015)

Heads up: There are no amended sections in this chapter.

Appendix G Flood-Resistant Construction

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This section has been amended at the state or city level.
Appendix G of the International Building Code is adopted in the District of Columbia and incorporated by reference as part of the Building Code with the following amendments.

G101.1 Purpose

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The purpose of this appendix is to promote the public health, safety and general welfare and to minimize public and private losses due to flood conditions in specific flood hazard areas through the establishment of comprehensive regulations in the Construction Codes for management of construction activities in flood hazard areas that meet the requirements of the National Flood Insurance Program for District of Columbia participation as set forth in the Code of Federal Regulations, Title 44, Section 59.22.

G101.2 Floodplain Management Regulations of the District of Columbia

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This section has been amended at the state or city level.
The flood-resistant construction provisions of the Construction Codes, including this appendix, in combination with the Department of Energy and Environment (DOEE)'s flood resilience rules, set forth in Title 20, Chapter 31 of the District of Columbia Municipal Regulations (DCMR), and Section 6-502 of the D.C. Official Code (2018 Repl.), comprise the Floodplain Management Regulations of the District of Columbia. The Floodplain Administrator retains all floodplain management responsibilities that are not assigned to the code official.

G101.2 G101.3 Objectives

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This section has been amended at the state or city level.
The objectives of this appendix, in combination with the flood-resistant construction provisions of the Construction Codes, are to protect human life, minimize the expenditure of public money for flood control projects, minimize the need for rescue and relief efforts associated with flooding, minimize prolonged business interruption, minimize damage to public facilities and utilities, help maintain a stable tax base by providing for the sound use and development of flood-prone areas, contribute to improved construction techniques in the floodplain and ensure that potential owners and occupants are notified that property is within flood hazard areas.

G101.3 G101.4 Scope

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This section has been amended at the state or city level.
The provisions of this appendix, in combination with the flood-resistant construction provisions of the Construction Codes, shall apply to all proposed development on a development site that is wholly or partially within a flood hazard area established in 20 DCMR Chapter 31, including certain work exempt from permit under Section 105.2 of the Building Code, 12-A DCMR.

G101.5 Administration and Enforcement

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This section has been amended at the state or city level.
The administrative and enforcement provisions of Chapter 1 of the Building Code, 12-A DCMR, shall apply to any development within the scope of this appendix, and to any permits and inspections relating thereto.

G101.4 G101.6 Violations

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This section has been amended at the state or city level.
Any violation of a provision of this appendix, or failure to comply with a permit or code modification associated with a permit issued pursuant to this appendix or any requirement of this appendix, shall be handled in accordance with the administration and enforcement provisions set forth in Chapter 1 of the Building Code, 12-A DCMR.

G101.7 Warning

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The degree of flood protection required by the Floodplain Management Regulations of the District of Columbia is considered the minimum reasonable degree of protection for regulatory purposes and is based on scientific and engineering considerations. Larger floods can and will occur. Flood heights may be increased by man-made or natural causes. This appendix does not imply that land outside of mapped flood hazard areas, or that uses permitted within such flood hazard areas, will be free from flooding or flood damage. No guarantee of vested use, existing use, or future use is implied or expressed by compliance with the Floodplain Management Regulations of the District of Columbia.

G101.8 Disclaimer of Liability

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This section has been amended at the state or city level.
The Floodplain Management Regulations of the District of Columbia shall not create liability on the part of the District of Columbia or by any official or employee thereof for any flood damage that results from reliance on the Floodplain Management Regulations of the District of Columbia or any administrative decision lawfully made thereunder.

G102.1 General

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This appendix, in conjunction with the Construction Codes, provides minimum requirements for development on a development site located wholly or partially within a flood hazard area.

G102.2 Establishment of Flood Hazard Areas

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Flood hazard areas are established in 20 DCMR Chapter 31.

G103.1 Permit Applications

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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.

G103.1.1 Determinations of Substantial Improvement and Substantial Damage

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This section has been amended at the state or city level.
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.

G103.1.1.1 Authority to Request Data

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This section has been amended at the state or city level.
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.

G103.2 Other Permits

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G103.3 G103.2 Determination of Design Flood Elevations

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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 do either of the following:
  1. Obtain, review and reasonably utilize data available from a federal, state or other source.
  2. Determine the design flood elevation in accordance with accepted hydrologic and hydraulic engineering techniques. Such analyses shall be performed and sealed by a registered design professional. Studies, analyses and computations shall be submitted in sufficient detail to allow review and approval by the code official. The accuracy of data submitted for such determination shall be the responsibility of the applicant.

G103.4 G103.3 Activities in Riverine Flood Hazard Areas

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This section has been amended at the state or city level.
In riverine flood hazard areas where design flood elevations are specified but floodways have not been designated, the code official shall not permit any new construction, substantial improvement or other development, including fill, on a development site, unless the applicant submits an engineering analysis prepared by a registered design professional in accordance with Section 1612.3.2; and such analysis is reviewed and approved by the Floodplain Administrator pursuant to 20 DCMR, Chapter 31.

G103.5 G103.4 Floodway Encroachment

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This section has been amended at the state or city level.
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.

G103.5.1 Floodway Revisions

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G103.6 G103.5 Watercourse Alteration

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Authorization to alter or relocate any watercourse shall be obtained from the Floodplain Administrator pursuant to 20 DCMR, Chapter 31.

G103.6.1 Engineering Analysis

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G103.7 Alterations in Coastal Areas

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G103.6 Review and Consultation by Floodplain Administrator

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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.

G103.8 Records

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G103.7 Coordination of Duties

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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.

G103.9 Inspections

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G103.8 Records

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The code official shall comply with the record retention requirements applicable to permits and associated documentation related to development on a development site wholly or partially within a flood hazard area, as set forth in 12-A DCMR, Section 104.7.

G104.1 Required

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This section has been amended at the state or city level.
Any person, owner or owner's authorized agent who intends to conduct any development of a development site located wholly or partially within a flood hazard area shall first make application to the code official and shall obtain the required permit in accordance with the administrative procedures set forth in Chapter 1 of the Building Code and this appendix..

G104.2 Application for Permit

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This section has been amended at the state or city level.
All applications proposing development of a development site located wholly or partially within a flood hazard area that is within the scope of this appendix shall comply with the requirements of the Building Code, 12-A DCMR Sections 105 and 106, and this appendix.

G104.2.1 Additional Information and Data Required

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This section has been amended at the state or city level.
Permit applications within the scope of this appendix shall, in addition to the information and data required by Sections 105 and 106 of the Building Code, include the following additional information and data as applicable:
  1. A site plan showing the delineation of flood hazard areas, floodway boundaries, base flood elevation(s), flood zones, design flood elevations, ground elevations, proposed fill and excavation and drainage patterns and facilities. Where not included on the FIRM or in the Flood Insurance Study, base flood elevations or floodway data shall be established in accordance with Section G103.2 of this appendix.
  2. For proposed developments with more than 50 tax lots or record lots or larger than 5 acres (20 234 m2), base flood elevation data in accordance with Section G103.2 of this appendix if such data are not identified for the flood hazard areas established in 20 DCMR Chapter 31. Where the base flood elevations are not included on the FIRM or in the Flood Insurance Study, such elevations shall be established in accordance with Section G103.3 of this appendix
  3. Location of the proposed work and proposed structures, and locations of existing buildings and structures.
  4. Location, extent, amount, and proposed final grades of any filling, grading, or excavation.
  5. Where the placement of fill is proposed, the amount, type, and source of fill material; compaction specifications; a description of the intended purpose of the fill areas; and evidence that the proposed fill areas are the minimum necessary to achieve the intended purpose.
  6. Existing watercourse[s] and approval by the Floodplain Administrator for any proposed alignment or proposed alteration thereof in accordance with Section G103.5.
  7. Information or data deemed necessary by the code official to make determinations of substantial improvement or substantial damage.
  8. "No-rise" certification for floodway encroachments in accordance with Section G103.4, as applicable.
  9. A floodway analysis for riverine flood hazard areas in accordance with G103.3 as applicable.
  10. Elevation Certificate(s) as required by Sections 105.3.2 and 1612.5.
  11. Floodproofing Certificate(s) as required by Sections 105.3.2 and 1612.5.
  12. Letter of Map Change, if applicable.
  13. An approved code modification in accordance with Section G10 for mixed-use projects with Residential Group R occupancies proposing underground garages located in basements (for flood loads).
  14. Such other data and information as required by the code official.

G104.3 Validity of Permit

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This section has been amended at the state or city level.
The issuance of a permit under this appendix shall not be construed to be a permit for, or approval of, any violation of this appendix or any other District of Columbia law or regulation. The issuance of a permit based on submitted documents and information shall not prevent the code official from requiring the correction of errors. The code official is authorized to prevent occupancy or use of a structure or site that is in violation of this appendix or other ordinances of this jurisdiction.

G104.4 Expiration

AMENDMENT
This section has been amended at the state or city level.
Expiration and extensions of permits issued under this appendix shall be governed by Sections 105.5 and 105.5.1 of the Building Code, 12-A DCMR.

G104.5 Suspension or Revocation

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This section has been amended at the state or city level.
Suspension or revocation of a permit issued under this appendix shall be governed by Section 111 of the Building Code, 12-A DCMR.

Section G105 Variances

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G105.1 General

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G105.2 Records

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G105.3 Historic Structures

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G105.4 Functionally Dependent Facilities

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G105.5 Restrictions

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G105.6 Considerations

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G105.7 Conditions for Issuance

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Section G105 Code Modifications

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G105.1 General

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The code official shall not grant modifications to any provision in the Construction Codes required in flood hazard areas, including but not limited to provisions of this appendix, unless the code modification complies with the procedures set forth in Section 104.10 of this code; the code modification request has been referred to the Floodplain Administrator for review and recommendation pursuant to 20 DCMR; and after the Floodplain Administrator's review and recommendation, a determination has been made by the code official that all of the following criteria are met:
  1. A technical showing of good and sufficient cause that the unique characteristics of the size, configuration or topography of the site render the elevation standards inappropriate.
  2. Failure to grant the code modification would result in exceptional hardship by rendering the lot undevelopable.
  3. Granting of a code modification will not result in increased flood heights, additional threats to public safety, extraordinary public expense, cause fraud on or victimization of the public, or conflict with existing laws or ordinances.
  4. The code modification is the minimum necessary to afford relief, considering the flood hazard.
  5. The applicant has been provided with written notice by the code official specifying the difference between the design flood elevation and the elevation to which the building is to be built, stating that the cost of flood insurance will be commensurate with the increased risk resulting from the reduced floor elevation, and stating that construction below the design flood elevation increases risks to life and property.
Exceptions:
  1. No code modifications shall be issued for any proposed development in a floodway if any increase in flood levels would result during the base flood discharge.
  2. The code official shall not issue a code modification that affects the base flood elevation without approval of the Floodplain Administrator pursuant to 20 DCMR, Chapter 31.

G105.2 Historic Structures

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This section has been amended at the state or city level.
Subject to review and approval by the Floodplain Administrator, the code official shall have authority to issue a code modification for proposed development of a historic structure on a development site located wholly or partially in a flood hazard area, upon the certification of the state historic preservation officer that: the proposed development will not preclude the structure's continued designation as a historic structure, and the code modification is the minimum necessary to preserve the historic character and design of the structure.

G105.3 Functionally Dependent Facilities

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This section has been amended at the state or city level.
A code modification is authorized to be issued for the construction or substantial improvement of a functionally dependent facility provided that the criteria in Section 1612.1 are met and the code modification is the minimum necessary to allow the construction or substantial improvement, and that all due consideration has been given to methods and materials that minimize flood damages during the design flood and create no additional threats to public safety.

Section G106 Inspections

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G106.1 General

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Work under a permit within the scope of this appendix shall be subject to inspection by the code official in accordance with Section 109 of the Building Code.

G106.2 Elevation Certificate

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This section has been amended at the state or city level.
An elevation certificate in accordance with Section 1612.5 shall be submitted to the code official and reviewed and approved by the Floodplain Administrator in accordance with the following:
  1. Upon placement of the lowest floor and prior to further vertical construction, as specified in Section 109.3.1.5.; and
  2. Prior to the final inspection or prior to the issuance of a conditional certificate of occupancy for core and shell, whichever is earlier as specified in Section 109.3.1.11.1.

G106.3 Floodproofing Certificate

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This section has been amended at the state or city level.
A floodproofing certificate in accordance with Section 1612.5 shall be submitted to the code official and reviewed and approved by the Floodplain Administrator prior to: (a) the final inspection, or (b) the issuance of a certificate of completion or the issuance of the first certificate of occupancy for a occupied space at grade or above, whichever of (a) or (b) is earlier, to certify a floodproofing design for a non-residential building that is permitted as an alternative to elevating to or above the base flood elevation as specified in Section 109.3.1.11.1.

Section G107 Violations

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This section has been amended at the state or city level.

G107.1 General

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The administrative and enforcement provisions of Chapter 1, 12-A DCMR are applicable to any violations of this appendix.

G107.1.1 Presumptive Violation

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This section has been amended at the state or city level.
A building or structure located on a development site wholly or partially within a flood hazard area, that is constructed or substantially improved pursuant to a permit issued by the code official after the effective date of the Construction Codes, but without the documentation of elevation of the lowest floor, other required design certifications, or other evidence of compliance required by the Construction Codes, shall be deemed to be in violation of the Construction Codes until such time as the requisite documentation is provided.

G201.1 General

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This section has been amended at the state or city level.
The following words and terms are defined in Chapter 2 of the Building Code.

ACCESSORY (for Appendix G)
ALTERATION OF A WATERCOURSE.
BASE FLOOD.
BASE FLOOD ELEVATION.
BASEMENT (for flood loads).
DESIGN FLOOD.
DESIGN FLOOD ELEVATION.
DEVELOPMENT.
DEVELOPMENT SITE.
ELEVATION CERTIFICATE.
ENCROACHMENT (for Appendix G).
FLOOD HAZARD AREA.
FLOOD INSURANCE RATE MAP (FIRM).
FLOOD INSURANCE STUDY (FIS).
FLOODPROOFING CERTIFICATE.
FLOODWAY.
FUNCTIONALLY DEPENDENT FACILITY.
HISTORIC STRUCTURE (for Appendix G).
LETTER OF MAP CHANGE.
LOWEST FLOOR.
MANUFACTURED HOME (for Appendix G).
MANUFACTURED HOME PARK OR SUBDIVISION (for Appendix G).
MARKET VALUE.
RECREATIONAL VEHICLE (for Appendix G).
SUBSTANTIAL DAMAGE.
SUBSTANTIAL IMPROVEMENT.

G201.2 Definitions

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G301.1 General

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Each application for subdivision of land in the District of Columbia sought pursuant to the provisions of the Subdivision Regulations of the District of Columbia (10-B DCMR §§ 2700 et seq.) shall be referred to the Floodplain Administrator for a determination as to whether the proposed development site that is the subject of the application is located wholly or partially within a flood hazard area.
The following requirements shall apply in the case of any proposed subdivision, including proposals for manufactured home parks and subdivisions, any portion of which lies within a flood hazard area:
  1. The flood hazard area, including floodways, coastal high-hazard areas and coastal A zones, as appropriate, shall be delineated on tentative and final subdivision plats.
  2. Design flood elevations shall be shown on tentative and final subdivision plats.
  3. Residential building lots shall be provided with adequate buildable area outside the floodway.
  4. The design criteria for utilities and facilities set forth in this appendix and appropriate International Codes shall be met.

G401.1 Development in Floodways

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G401.1 Compliance With DOEE's Resilience Rules

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Any site improvements in a flood hazard area shall comply with requirements in 20 DCMR Chapter 31.

G401.2 Coastal High-Hazard Areas and Coastal A Zones

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G401.2 Approval of Site Improvements

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The owner shall obtain code official approval of civil drawings for site work/groundwork pursuant to an application for a civil site work (BCIV) permit, as part of a building permit application, or as otherwise directed by the code official for any proposed development on a development site that is located wholly or partially within a flood hazard area.

G401.3 Sewer Facilities

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All new or replaced sanitary sewer facilities, private sewage treatment plants (including all pumping stations and collector systems) and on-site waste disposal systems for any proposed development on a development site that is located wholly or partially within a flood hazard area shall be designed in accordance with Chapter 7, ASCE 24, to minimize or eliminate infiltration of flood waters into the facilities and discharge from the facilities into floodwaters, or impairment of the facilities and systems.

G401.4 Water Facilities

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All new or replacement water facilities for any proposed development on a development site that is located wholly or partially within a flood hazard area shall be designed in accordance with the provisions of Chapter 7, ASCE 24, to minimize or eliminate infiltration of floodwaters into the systems.
Storm drainage shall be designed to convey the flow of surface waters to minimize or eliminate damage to persons or property.
Streets and sidewalks shall be designed to minimize potential for increasing or aggravating flood levels.

G501.1 Elevation

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All new and replacement manufactured homes to be placed or substantially improved on a development site that is located wholly or partially within a flood hazard area shall be elevated such that the lowest floor of the manufactured home is elevated to or above the design flood elevation.

G501.2 Foundations

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This section has been amended at the state or city level.
All new and replacement manufactured homes, including substantial improvement of existing manufactured homes, shall be placed on a permanent, reinforced foundation on a development site that is located wholly or partially within a flood hazard area that is designed in accordance with Section R322 of the Residential Code.

G501.3 Anchoring

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This section has been amended at the state or city level.
All new and replacement manufactured homes to be placed or substantially improved on a development site that is located wholly or partially within a flood hazard area shall be installed using methods and practices that minimize flood damage. Manufactured homes shall be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement. Methods of anchoring are authorized to include, but are not limited to, use of over-the-top or frame ties to ground anchors. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces.

G501.4 Protection of Mechanical Equipment and Outside Appliances

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This section has been amended at the state or city level.
Mechanical equipment and outside appliances for any proposed development on a development site that is located wholly or partially within a flood hazard area shall be elevated to or above the design flood elevation.
Exception: Where such equipment and appliances are designed and installed to prevent water from entering or accumulating within their components and the systems are constructed to resist hydrostatic and hydrodynamic loads and stresses, including the effects of buoyancy, during the occurrence of flooding up to the elevation required by Section R322 of the Residential Code, the systems and equipment shall be permitted to be located below the elevation required by Section R322 of the Residential Code. Electrical wiring systems shall be permitted below the design flood elevation provided they conform to the provisions of NFPA 70.

G501.5 Enclosures

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Fully enclosed areas below elevated manufactured homes that are located wholly or partially within a flood hazard area shall comply with the requirements of Section R322 of the Residential Code.

G601.1 Placement Prohibited

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The placement of recreational vehicles wholly or partially within a flood hazard area shall not be authorized in coastal high-hazard areas and in floodways.

G601.2 Temporary Placement

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Recreational vehicles located wholly or partially within a flood hazard areashall be fully licensed and ready for highway use, and shall be placed on a site for not more than 180 consecutive days.

G601.3 Permanent Placement

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This section has been amended at the state or city level.
Recreational vehicles located wholly or partially within a flood hazard area that are not fully licensed and ready for highway use, or that are to be placed on a site for more than 180 consecutive days, shall meet the requirements of Section G501 for manufactured homes.

G701.1 Tanks

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This section has been amended at the state or city level.
Underground and above-ground tanks located wholly or partially within flood hazard areas shall be designed, constructed, installed and anchored in accordance with ASCE 24.

G801.1 Garages and Accessory Structures

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This section has been amended at the state or city level.
Garages and accessory structures located wholly or partially within flood hazard areas shall be designed and constructed in accordance with ASCE 24 and comply with the following conditions as applicable.

G801.1.1 DOEE Covenant Required

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This section has been amended at the state or city level.
No permit to construct or to make substantial improvement in an accessory structure located wholly or partially within a flood hazard area will be issued by the Department without evidence of DOEE's approval of a non-conversion agreement not to convert the accessory structure to a residential use.

G801.1.2 Size Limitation

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This section has been amended at the state or city level.
No code modifications or variances will be granted to allow an accessory structure located wholly or partially within a flood hazard area to exceed 600 square feet (55.74 m2).

G801.1.3 Exception to Chapter 16 Requirements for Certain Accessory Structures

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This section has been amended at the state or city level.
Accessory structures that are less than 600 square feet (55.74 m2) in area and are not elevated or dry floodproofed in accordance with Chapter 16 of the Building Code are allowed where the accessory structure meets the following conditions:
  1. Constructed with flood damage-resistant materials below the design flood elevation;
  2. Constructed and placed to offer the minimum resistance to the flow of floodwaters;
  3. Anchored to prevent flotation;
  4. Electrical service and mechanical equipment elevated to or above the design flood elevation; and
  5. Provided with flood openings that meet the following criteria:
    1. There shall be a minimum of two flood openings on different sides of each enclosed area; if an accessory structure has more than one enclosure below the lowest floor, each such enclosure shall have flood openings on exterior walls;
    2. The total net area of all flood openings shall be at least one square inch for each one square foot of enclosed area (non-engineered flood openings), or the flood openings shall be engineered flood openings that are designed and certified by a licensed professional engineer to automatically allow entry and exit of floodwaters; the certification requirement is allowed to be met by the professional engineer's certification or by submission of an Evaluation Report issued by the ICC Evaluation Service or another approved entity;
    3. The bottom of each flood opening shall be one foot or less above the higher of either the interior floor or grade or the exterior grade immediately below the opening; and
    4. Any louvers, screens, or other covers for the flood openings shall allow the automatic flow of floodwaters into and out of the enclosed area.

G801.1.4 Underground Garages in Basements

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This section has been amended at the state or city level.
Underground garages located in basements (for flood loads) of an existing or proposed building or structure that: (a) is located on a development site wholly or partially within a flood hazard area, and (b) is used or will be used partially for Residential Group R occupancies, including a mixed use building with Residential Group R occupancies, will not be approved in permit applications for new construction or substantial improvement, without a code modification granted pursuant to Section G105.

G801.2 Fences

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This section has been amended at the state or city level.
Fences in floodways that may block the passage of floodwaters, such as stockade fences and wire mesh fences, shall meet the requirement of Section G103.4.

G801.3 Oil Derricks

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This section has been amended at the state or city level.
Oil derricks located wholly or partially in flood hazard areas shall be designed in conformance with the flood loads in Sections 1603.1.7 and 1612.

G801.4 Retaining Walls, Sidewalks and Driveways

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This section has been amended at the state or city level.
Retaining walls, sidewalks and driveways located wholly or partially within flood hazard areas shall meet the requirements of Section 1804.5.

G801.5 Swimming Pools

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This section has been amended at the state or city level.
Swimming pools located wholly or partially within flood hazard areas shall be designed and constructed in accordance with ASCE 24. Above-ground swimming pools, on-ground swimming pools and in-ground swimming pools that involve placement of fill in floodways shall also meet the requirements of Section G103.4.

G801.6 Decks, Porches, and Patios

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This section has been amended at the state or city level.
Decks, porches and patios located wholly or partially within flood hazard areas shall be designed and constructed in accordance with ASCE 24.

G801.7 Nonstructural Concrete Slabs in Coastal High-Hazard Areas and Coastal A Zones

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This section has been amended at the state or city level.

G801.8 G801.7 Roads and Watercourse Crossings in Regulated Floodways

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This section has been amended at the state or city level.
Roads and watercourse crossings that encroach into regulated floodways, including roads, bridges, culverts, low-water crossings and similar means for vehicles or pedestrians to travel from one side of a watercourse to the other, shall meet the requirement of Section G103.4.

Section G802 Mixed-Use Buildings

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G802.1 Lowest Floor

AMENDMENT
This section has been amended at the state or city level.
The lowest floor (including basement or underground parking garage) of any new construction of, or substantial improvement to, a mixed-used building located on a development site wholly or partially within a flood hazard area shall either be at or above the design flood elevation, or be designed and constructed to be dry floodproofed during any flood up to the design flood elevation.

G802.2 Residential Portion

AMENDMENT
This section has been amended at the state or city level.
The lowest floor of the residential portion of any new construction of, or substantial improvement to, a mixed-use building located on a development site wholly or partially within a flood hazard area shall be at or above the design flood elevation.

G802.3 Non-Residential Portion

AMENDMENT
This section has been amended at the state or city level.
The non-residential portion of any new construction of, or substantial improvement to, a mixed-use building located on a development site wholly or partially within a flood hazard area shall either be at or above the design flood elevation, or be designed and constructed to be dry floodproofed during any flood up to the design flood elevation.

G802.4 Ancillary Residential Use Portion

AMENDMENT
This section has been amended at the state or city level.
The lowest floor of the ancillary residential use portion of any new construction of, or substantial improvement to, a mixed-use building located on a development site wholly or partially within a flood hazard area shall either be at or above the design flood elevation, or be designed and constructed to be wet floodproofed during any flood up to the design flood elevation.

G901.1 Temporary Structures

AMENDMENT
This section has been amended at the state or city level.
Temporary structures located wholly or partially within flood hazard areas shall comply with Section 119 of the Building Code, 12-A DCMR, and with the following conditions:
  1. Temporary structures shall be anchored to prevent flotation, collapse or lateral movement resulting from hydrostatic loads, including the effects of buoyancy, during conditions of the design flood.
  2. Fully enclosed temporary structures shall have flood openings that are in accordance with ASCE 24 to allow for the automatic entry and exit of floodwaters.

G901.2 Temporary Storage

AMENDMENT
This section has been amended at the state or city level.

G901.3 G901.2 Floodway Encroachment

AMENDMENT
This section has been amended at the state or city level.
Temporary structures and temporary storage in floodways shall meet the requirements of Section G103.4.
Utility and miscellaneous Group U includes buildings that are accessory in character and miscellaneous structures not classified in any specific occupancy in this code, including, but not limited to, agricultural buildings, aircraft hangars (accessory to a one- or two-family residence), barns, carports, fences more than 6 feet (1829 mm) high, grain silos (accessory to a residential occupancy), greenhouses, livestock shelters, private garages, retaining walls, sheds, stables and towers.

G1001.2 Flood Loads

AMENDMENT
This section has been amended at the state or city level.
Utility and miscellaneous Group U buildings and structures located wholly or partially within flood hazard areas, including substantial improvement of such buildings and structures, shall be anchored to prevent flotation, collapse or lateral movement resulting from flood loads, including the effects of buoyancy, during conditions of the design flood.

G1001.3 Elevation

AMENDMENT
This section has been amended at the state or city level.
Utility and miscellaneous Group U buildings and structures located wholly or partially within flood hazard areas, including substantial improvement of such buildings and structures, shall be elevated such that the lowest floor, including basement, is elevated to or above the design flood elevation in accordance with Section 1612 of this code.

G1001.4 Enclosures Below Design Flood Elevation

AMENDMENT
This section has been amended at the state or city level.
Fully enclosed areas located wholly or partially within flood hazard areas below the design flood elevation shall be constructed in accordance with ASCE 24.
Flood-damage-resistant materials shall be used below the design flood elevation.

G1001.6 Protection of Mechanical, Plumbing and Electrical Systems

AMENDMENT
This section has been amended at the state or city level.
Mechanical, plumbing and electrical systems, including plumbing fixtures, located wholly or partially within flood hazard areas shall be elevated to or above the design flood elevation.
Exception: Electrical systems, equipment and components; heating, ventilating, air conditioning and plumbing appliances; plumbing fixtures, duct systems and other service equipment shall be permitted to be located below the design flood elevation provided that they are designed and installed to prevent water from entering or accumulating within the components and to resist hydrostatic and hydrodynamic loads and stresses, including the effects of buoyancy, during the occurrence of flooding to the design flood elevation in compliance with the flood-resistant construction requirements of this code. Electrical wiring systems shall be permitted to be located below the design flood elevation provided they conform to the provisions of NFPA 70.

Section G1101 Referenced Standards

AMENDMENT
This section has been amended at the state or city level.
ASCE 24—14 Flood Resistant Design
and Construction
G103.1,
G401.3,
G401.4, G701.1,
G801.1, G801.5,
G801.6, G801.7,
G901.1, G1001.4
HUD 24 CFR
Part 3280
(2008)
Manufactured Home
Construction and Safety
Standards
G201
NFPA 70—14 National Electrical Code G501.4, G1001.6
FEMA P-758
(May 2010)
Substantial Improvement /
Substantial Damage Desk Reference
G103.1.1
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