ENVIRONMENTAL BUSINESS
Breaking Down the Latest Stormwater Rules
By : Ahmad Tamous , PE , PP
What It Means for New Jersey Developers
On December 5 , 2022 , the New Jersey Department of Environmental Protection ( NJDEP ) published the long-awaited Flood Hazard Area ( FHA ) Control Act Rule and Stormwater Management Rule , which is anticipated to be adopted in the second quarter of 2023 . This is a departure from the initial timeline for the rules , invoked using the NJDEP ’ s emergency rule-making powers . The agency is now following the traditional regulation change review process and the rules are currently open for public comment and review .
The new rules , once adopted , will impact all proposed land development projects in the state of New Jersey , with a few exceptions , listed below .
Inland and Fluvial Flood Hazard Rules
All Federal Emergency Management Agency ( FEMA ) -established non-tidal flood elevations will increase as follows :
◾ Flood elevations mapped by NJDEP will increase by two feet .
◾ FEMA ’ s 100-year flood elevations will increase by three feet .
Note : Tidal flood elevations are not affected .
◾ Flood Hazard Area ( FHA ) elevations determined by approximate methods will increase by one foot .
When calculating flood elevations , the new rules will require the use of projected precipitation volumes for the calculations . Projected volumes are typically greater than current volumes , and therefore will likely increase the flood elevations .
What This Means for Developers
With the new elevations , a property that currently sits outside a floodplain could now fall into a floodplain zone or FHA and be subject to all associated NJDEP permitting requirements .
If a site is in a floodplain , its yield , density , and overall developability may also be limited , depending upon how much of the site falls within the floodplain under the new rule .
Land Development Projects Are Exempt If :
◾ The project is currently under a valid individual permit with the NJDEP . Note that an FHA verification is not a permit and does not exempt a project from having to comply with these changes .
◾ The project ’ s FHA permit application is deemed substantially and technically complete by the NJDEP according to the agency ’ s applicable checklist before the new rule takes effect .
Ahmad Tamous , PE , PP
◾ The project needs Coastal Zone Management ( CZM ), Fresh Water Wetlands ( FWW ), or Highlands approval and a complete application is submitted to NJDEP prior to adoption of the new regulations .
◾ The project does not require NJDEP approval and receives local approvals pursuant to Municipal Land Use Law ( MULL ) prior to adoption .
Stormwater Rules
Under the Control Act Rule , the design of all stormwater management facilities for all new proposed land development projects in the state of New Jersey will be required to account for a higher intensity rainfall . Additionally , the NJDEP is amending the Groundwater Recharge Standards , which will require infiltration areas to also be calculated using the new higher intensity rainfall .
Sewer bridge through a ditch by the road . concrete hole with surroundings of stone paving .
Photo : Getty Images / iStockphoto / beekeepx
◾ All projects subject to Residential Site Improvements Standards ( RSIS ) will immediately be subject to these new stormwater requirements , even if they do not require an NJDEP permit . This affects all single-family residential subdivisions , multifamily communities , assisted living communities , and all other residential projects under RSIS .
◾ All other projects will be required to follow the new requirements when the applicable municipality adopts them . NJDEP has given municipalities one
Continued On Page 20
January 2023 COMMERCE 19