The peak runoff from the site is summarized below.
POA 2-Year 10-Year 100-Year 2-Year 10-Year 100-Year
1 0.0 0.0 0.0 0.0 0.0 0.25
2 0.0 0.0 0.10 0.0 0.0 0.25
3 0.0 0.0 0.07 0.0 0.0 0.20
PROPOSED PEAK RUNOFF (CFS)
CURRENT ADJUSTED FUTURE ADJUSTED
The proposed storm sewers have been designed in accordance with relevant requirements. The storm sewer was designed using the Rational method, the NJ Intensity-Duration-Frequency table, and a time of concentration minimum of 10 minutes. The storm sewers were sized to convey a 25-year storm event.
Storm sewer calculations are included in the Appendix.
In accordance with N.J.A.C. 7:8-5.5(b) stormwater management measures shall be designed to reduce the post-construction load of total suspended solids (TSS) in stormwater runoff generated from the water quality design storm by eighty percent TSS removal of the anticipated load, expressed as an annual average for the stormwater runoff from the net increase of motor vehicle surface.
Currently, the site contains 0.26 acres of motor vehicle surface which does not receive water quality treatment.
The proposed site will contain 0.79 acres of motor vehicle surface for a net increase of 0.53 acres. As the existing motor vehicle surface does not receive water quality treatment, the equivalent redevelopment area would only require 50% TSS removal. This credit can be used to offset the portions of the proposed driveways that will run off untreated. However, the entire proposed motor vehicle surface will be treated for 80% TSS removal and so the proposed stormwater management will exceed the required TSS removal for the site.
| REGULATED MOTOR VEHICLE SURFACE (ACRE) | ||
| Existing | Proposed | Net Change |
|---|---|---|
| 0.26 | 0.79 | 0.53 |
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