Stormwater report reveals alarming increase in runoff volume

In a recent government meeting, discussions centered around the implications of a stormwater report submitted by an applicant, revealing a significant increase in stormwater runoff volume in developed conditions compared to existing conditions. The report, which was scrutinized by officials, confirmed that the applicant's approach to stormwater management raised concerns regarding groundwater recharge.

Dr. Demerson, an expert in stormwater management, highlighted the New Jersey Department of Environmental Protection (DEP) regulations, specifically referencing NJAC 7:5.4, which mandates that applicants demonstrate sufficient groundwater recharge. The DEP allows two methods for this demonstration: one involves calculating runoff from a two-year storm to ensure no increase in volume post-development, while the second method assesses annual recharge budgets.

The applicant opted for the second method, which, according to Dr. Demerson, could be misleading. He explained that if the existing soil is classified as type D, it is considered to produce zero recharge, allowing the applicant to meet recharge criteria without actual groundwater replenishment. This has raised concerns among officials, who noted that this approach could be perceived as a loophole, effectively providing a \"get out of jail free card\" for developers.

Further analysis revealed that the applicant's report indicated not only an increase in runoff volume from the two-year storm but also projected increases for ten-year and hundred-year storms, with estimates suggesting more than a twofold increase. This finding has prompted objections from officials regarding the relevance and implications of the applicant's stormwater management strategy.

The Delaware and Raritan Canal Commission has signed off on the application, but the discussions underscore the ongoing debate about the adequacy of stormwater management practices and their impact on local water resources. As the meeting concluded, officials expressed the need for further scrutiny of such applications to ensure compliance with environmental regulations and the protection of groundwater resources.