NJDEP Announces Filing of Inland Flood Protection Rule

On June 6, 2023, New Jersey Governor Philip Murphy announced the Administration’s upcoming adoption of the Inland Flood Protection Rule to better protect New Jersey’s communities from worsening riverine flooding and stormwater runoff. The rulemaking was filed with the Office of Administrative Law and was adopted, effective on July 17, 2023, after publication in the New Jersey Register. A courtesy copy of the rule and additional information are available here.

The Inland Flood Protection Rule updates New Jersey’s existing flood hazard and stormwater regulations by replacing outdated precipitation estimates with modern data that account for observed and projected increases in rainfall. These changes will help reduce flooding from stormwater runoff and increase the resilience of new developments located in flood-prone inland areas. Upon adoption, New Jersey will become the first state to use predictive precipitation modeling to implement rules to inform and protect future development and redevelopment from the impacts of climate change.

“The Inland Flood Protection Rule will serve as a critical component of my Administration’s comprehensive strategy to bolster our state’s resilience amid the worsening impacts of climate change,” said Governor Murphy. “As a national model for climate adaptation and mitigation, we can no longer afford to depend on 20th-century data to meet 21st-century challenges. This rule’s formation and upcoming adoption testify to our commitment to rely on the most up-to-date science and robust stakeholder engagement to inform our most crucial policy decisions.”

Inland Flood Protection Rule Overview

The Inland Flood Protection Rule establishes design elevations that are reflective of New Jersey’s changing climate and more frequent and intense rainfall, replacing standards based on outdated data and past conditions. The updated standards will apply to certain new and substantially reconstructed developments in inland riverine areas that are subject to flooding, but they do not prohibit development in these flood hazard areas.

Under the two primary components of the rule:

1. The elevation of habitable first floors will be two feet higher than currently indicated on NJDEP state flood maps and three feet higher than indicated on FEMA maps.
2. Applicants for certain permits will use NJDEP’s New Jersey-specific precipitation data when calculating peak flow rates of streams and rivers for permits under the Flood Hazard Area Control Act Rules, N.J.A.C. 7:13, as well as when proposed development triggers compliance with DEP’s Stormwater Management rules, N.J.A.C. 7:8.

The updated standards in the Inland Flood Protection Rule will apply to new or reconstructed developments and not to existing developments. Pending development applications before NJDEP that are administratively complete at the time of adoption are not affected by these changes. Existing provisions of the flood hazard and stormwater rules that provide flexibility from strict compliance based on unique site-specific conditions will remain in place, along with new provisions designed to ensure that infrastructure projects already in progress can continue to move forward.

The final rule also provides clarifications for the legacy provision of the Flood Hazard Area Control Act rules at N.J.A.C. 7:13-2.1 to address projects that were wholly located outside the prior flood hazard area, and which have already received local approval under the Municipal Land Use Law. As initially proposed, this exemption from the new flood elevations would have been limited to those projects that had begun construction before the new rules were adopted. In recognition of the often-significant investments made for projects that have reached the stage of receiving municipal approval, NJDEP is retaining the existing exemption for such projects.

New Jersey’s Flood Indicator Tool

“New Jersey’s communities are facing unprecedented threats from the devastating impacts of extreme rainfall events, which are expected to continue to intensify in their frequency and severity,” said Commissioner of Environmental Protection Shawn M. LaTourette. “The Inland Flood Protection Rule ensures that inland, riverine areas at significant risk are better defined and that new and reconstructed assets in these areas are designed and constructed to protect New Jersey’s assets, economy and, above all, our people from the catastrophic effects of worsening floods. My DEP colleagues and I are truly grateful for Governor Murphy’s vision and leadership and for the thoughtful feedback we have received from the public and leaders in labor, business, local government, academia, and advocacy in designing this rule as part of the New Jersey Protecting Against Climate Threats (NJ PACT) initiative.”

In connection with the proposed Inland Flood Protection Rule, to aid the public to gauge flood risk and provide a visual approximation of regulatory jurisdiction on specific parcels, NJDEP has launched a flood indicator tool.  While the tool does not provide a definitive demonstration of regulatory jurisdiction or calculate actual risk, it can be useful in assisting property owners or prospective property owners on potential risk and, by referencing the 500-year flood extent, approximate NJDEP’s regulatory jurisdiction and flood risk. Equipped with this information, property owners may then decide to take additional steps to determine actual risk, which is dependent on site-specific conditions.

For more information on Princeton Hydro’s stormwater management, flood mitigation, and resilience services, please contact us here.

• Climate Change
• Flood Mitigation
• Resiliency
• Stormwater Management