Parsippany-Troy Hills, NJ Environmental Rules: Stormwater Management (2026)

Article XVI, Stormwater Management Controls, was added 5-18-2021 by Ord. No. 2021:08 and amended in 2022 and 2024. Section 225-94 states that its minimum requirements for major and minor development are meant to meet and exceed the New Jersey Stormwater Management Rules at N.J.A.C. 7:8. It applies to nonresidential development, to the parts of residential development not preempted by the Residential Site Improvement Standards, and to all major and minor development in the Township, public or private. Applications submitted before August 1, 2024 stay under the requirements in effect on July 31, 2024.

Major development must provide erosion control, groundwater recharge, runoff quantity control and runoff quality treatment, and section 225-96 requires the recharge, quality and quantity standards to be met by incorporating green infrastructure. Section 225-97 adds a maintenance plan under § 225-104 and bars adverse effects of concentrated flow on habitat for threatened and endangered species, naming swamp pink and bog turtle.

Minor development follows § 225-98. Seepage pits or other infiltration measures must hold three inches of runoff for each square foot of new impervious area, using 2 1/2 inch clean stone at a 33% design void ratio, with a surface overflow that is stabilized. Alternatives such as infiltration chambers, rain gardens, infiltration beds or rain water harvesting are acceptable if approved by the Township Engineer. Underground roof leader pipes must be perforated pipe in a stone bed. Single lot, single-family properties skip the maintenance plan and soil testing but maintain measures under the NJDEP BMP Manual.

Basin safety is set in § 225-102: trash rack bars no more than six inches apart, overflow grate spacing no greater than two inches, a design live load of 300 pounds per square foot, and safety ledges where a permanent pool is deeper than 2 1/2 feet. The maximum interior slope of an earthen dam, embankment or berm is three horizontal to one vertical. Applicants file five copies of the site development stormwater plan under § 225-103.