The D.C. Department of Energy and Environment (DOEE) on July 19, 2024, published a proposed rulemaking (Proposed Rule) to adopt amendments to the District's Flood Hazard Rules (Rules) contained in Chapter 31, Title 20 of the District of Columbia Municipal Regulations (DCMR). These proposed changes are designed to make the District more resilient in the light of climate change, sea level rise and extreme rainfall events, including preparing residents and structures for flood events and minimizing public and private losses caused by flooding.

This much-anticipated Proposed Rule comes after several years of stakeholder engagement by DOEE that began in 2020 when DOEE previewed its updates to the Flood Hazard Rules to address the increased risk of flooding posed by climate change and sea level rise. (See Holland & Knight's previous alert, "D.C.'s Department of Energy & Environment Proposes Major Changes to Flood Hazard Regulations," April 7, 2020.) As part of its engagement process, DOEE solicited informal public comments on proposed modifications to the Rules and held technical workshops on various topics, including mapping and delineation, vesting and timing for implementation of rule changes, and issues relevant to commercial, mixed-use and multifamily buildings.

Critically, the Flood Hazard Rules currently govern activities such as building construction within the Federal Emergency Management Agency's (FEMA) 100-year floodplain. The Proposed Rule would expand the regulated "flood hazard area" to include lands within the FEMA 500-year floodplain, including any area that has been removed from a flood hazard area due to a Letter of Map Revision Based on Fill (LOMR-F) and areas on Rhode Island Avenue NE that are susceptible to interior flooding (i.e., those below a Design Flood Elevation of 96.5 feet). If a property is partially within a flood hazard area, the proposed regulations will not apply if the structure is completely outside the flood hazard area. DOEE noted that several other cities – including Houston, Baltimore and Austin – have recently adopted regulations impacting development within the 500-year floodplain. DOEE received significant input on the flood hazard definition in its 2020 preview of the proposed amendments, including comments from the development community regarding additional financial burdens that would be imposed on developers building within the 500-year floodplain. DOEE states that it commissioned two cost-benefit analysis reports, which concluded that these flood mitigation retrofits would provide a 6-to-1 return on investment from avoided damages and that the bulk of these costs would be incurred in Wards 6, 7 and 8. Notably, in response to those comments, DOEE removed the proposed requirement that property owners/developers within the 500-year flood hazard area would have to provide proof of flood insurance prior to final inspection of the structure and continuously for the life of the structure.

Other significant changes to the current Flood Hazard Rules outlined in the Proposed Rule include:

• Substantial Improvements. The Proposed Rule would modify the definition of "substantial improvement" to include any "any combination of repairs, reconstruction, rehabilitation, additions, modifications, or improvements of a building or structure made during the 5-year period immediately preceding a permit application." (emphasis added) The Proposed Rule provides a slightly modified definition of "substantial improvement" for changes in the 500-year floodplain: The full requirements of the rule would not apply if the improvements are made to a detached one- or two-family dwelling or townhouse not more than three stories above grade, with a separate means of egress located completely outside the flood hazard area, if the improvements cost less than $200,000. There is no comparable exemption for multifamily buildings. These proposed changes represent a significant departure from the current definition of "substantial improvement," which is any repair or improvement that equals or exceeds 50 percent of the assessed value of the structure before the start of construction. DOEE has indicated that the intent of this proposed revision is to prevent applicants from obtaining minor permits for smaller projects to avoid being classified as a substantial improvement.
• Design Flood Elevation. The Proposed Rule changes the design flood elevation (DFE) to either the 100-year flood elevation plus two feet (2 ft.) of freeboard or the 500-year flood elevation, whichever is higher. The current Flood Hazard Rules require buildings to be elevated or floodproofed to plus one and one-half feet (1.5 ft.) of freeboard. The current D.C. Construction Codes apply these requirements within the 100-year floodplain, but the requirements would be expanded to encompass the 500-year floodplain as well.
• Covenants and Agreements. Applicants would need to file a covenant regarding the operation and maintenance obligations for dry floodproofing systems. They would also need to file in the land records a nonconversion agreement so that an approved nonresidential use is not later converted to a residential use. DOEE intends to post templates and model agreements on its website at a later date.
• No Adverse Impact. The Proposed Rule would require applicants to demonstrate that their proposed development in a flood hazard area will cause no adverse impact to other properties due to the development increasing the regulatory flood elevation or expanding the flood zone. This would be done via a No Rise Certification. Some exceptions are provided for projects such as stream restoration or flood control.
• Hazardous Materials. The current Flood Hazard Rules require new or substantially improved structures that will be used for the production or storage of more than 550 gallons of 18 "potentially dangerous materials" to obtain special permits. The Proposed Rule would expand on this to require property owners/developers to report the storage of a more expansive list of hazardous materials and to prepare a flood emergency action plan to deal with hazardous materials. The flood emergency plan could be incorporated into a Spill Prevention, Control and Countermeasures Plan (SPCC) or Stormwater Pollution Prevention Plan (SWPPP) if the facility is otherwise required to have one of these plans. These properties would also have to comply with the proposed requirements for "critical facilities."
• Critical Facilities. The Proposed Rule prohibits new or substantially improved critical facilities in flood hazard areas without an alternatives analysis and stringent protective measures. The list of proposed critical facilities is expansive and includes hospitals and healthcare facilities, police and fire stations, shelters and short-term family housing facilities, housing owned or operated by the District, schools and childcare facilities, emergency shelters, power-generating stations, facilities storing or using hazardous materials, and numerous other structures – such as communication towers and fuel or water storage tanks – that are critical during an emergency. Public housing units are not included on the list of critical facilities.
• Underground Parking Garages. The Proposed Rule maintains the existing prohibition on underground parking garages below residential-only multifamily structures in the 100-year floodplain. Communal spaces, gyms and other non-dwelling amenities accessible only to residents will need to be elevated in buildings in the 100-year floodplain (rather than floodproofed). Under the proposed amendments, mixed-use projects would now be allowed to have underground parking garages "by right" and no longer need to obtain a variance or code modification. This is an important change that was negotiated with FEMA staff, as it previously was unclear whether mixed-use buildings would be considered residential or nonresidential under FEMA guidance.
• Historic Structures. Historic structures are not addressed under the current Flood Hazard Rules. The Proposed Rule would require coordinated review with the State Historic Preservation Office (SHPO) to ensure that required floodproofing is achieved to the maximum extent practicable while still maintaining the structure's historic designation.
• Tidal Shoreline Buffer. The Proposed Rule seeks to create a Tidal Shoreline Buffer that would include areas that are expected to be inundated by sea level rise by the year 2080 (DOEE's 2020 previewed amendments used the year 2100). Only 1 percent of private land is located within the proposed Tidal Shoreline Buffer area. The amendments would prohibit any nonresidential space below the tidal shoreline flood elevation from being converted to residential use. Further, any applicant for new construction or substantial improvements in the Tidal Shoreline Buffer would need to submit certain information to DOEE, including an evaluation plan, a comprehensive resilient systems plan and an alternatives analysis.
• Mixed-Use Projects. Mixed-use projects are not addressed under the District's current Flood Hazard Rules. The Proposed Rule would require the lowest floor of any mixed-use building to be at or above the DFE or designed and constructed to be dry-floodproofed during any flood up to the DFE. The lowest floor of the residential portion of any mixed-use building would be required to be at or above the DFE. The Proposed Rules also would prohibit the conversion of any nonresidential space below the DFE to residential use.
• Administrative Roles. The Proposed Rule spells out the respective roles of the DOEE Director, Department of Buildings (DOB) and Historic Preservation Office (HPO). The DOEE Director is expected to coordinate the review and approval process with DOB to ensure that the site is reasonably safe from flooding. The HPO is expected to review any permit application for repair or rehabilitation of historic structures.
• Fees. DOEE proposes new fees to administer the program, ranging from approximately $800 for one- to two-unit dwellings to up to $10,000 for major developments involving four or more floors or six or more residential units. DOEE proposes a series of additional fees for various activities, ranging from having a predevelopment meeting to reviewing hydrologic and hydraulic studies to resubmission fees if the application has to be submitted four or more times.
• Transition and Implementation. DOEE is proposing that the amendments to the Flood Hazard Rules be enforced on the date of publication of the final rule. DOEE's justification for this is that it has been publicly discussing the amendments with the regulated community since March 2020. Further, DOEE proposes that any development project within a flood hazard area that has not submitted a complete application within 30 days of the date of publication of the final rule will be subject to the amended requirements. However, for any projects that have received an approval or final report from various agencies (including SHPO, the Commission on Fine Arts, Zoning Board for a variance, etc.) that DOEE determines conflicts with the amended rules will be permitted to comply with the prior rules, provided that a permit is obtained within six months of publication of the amended rules.

DOEE is accepting public comments on the Proposed Rule until Sept. 2, 2024. Comments should be submitted via email.