15 Ridgeway Ave Minor Subdivision Rev 3 Dated 4 13 26 File 29906

RESTRICTION AND OUTFLOW MAX OUTFLOW 4 Q = 2.26 cfs 563.00 8” FES 6’x12’ 4” Rip Rap Level Spreader STUDY POINT FOR ANALYSIS 10” SDR 35 PVC DRAIN CONNECTED TO PUBLIC STORM SEWER! PRE DEVELOPED Q 2yr = 0.38 cfs Q 10yr = 0.95 cfs Q 100yr= 2.26 cfs Q P 2yr = 0.57 cfs QP 10yr = 1.31 cfs QP 100 yr = 3.17 cfs DEVELOPED Q 100yr= 1.80 LOT 21.01 | Seeeeeneee | PROPOSED 2 STORY, / DWELLING FF ELEV = 570.0 GF ELEV = 568.0 ~~ 2nd FLOOR 2 OVERHANG: PROPOSED carace sis |} CURBED DRIVEWA ELEV = 568.0 24.0° Q 2yr = 0.19 cfs Q 10yr = 0.66 cfs aa \ \ NEW LOT 28.04 < 26,850 SF 2 — + * Post development runoff is reduced for all design storms from what would have occurred if the site was undeveloped and wooded. No credit taken in cfs QP 2yr = 0.26 cfs Q P 10yr = 0.90 cfs QP 100 yr = 2.33 cfs the analysis for existing impervious to remain. / LOT 21 po Top Wall = 566.0 TC. PATH A _PROPOSED BYPASS 5.8 minutes .~” Landscape Block Wall Max Height 36” LUMINUM PICKET FENCE 6a Area(sf) CN Description | oe eo EXISTING DRAINAGE AREA BOUNDARY (—_—— ) ( ee ) UMINUM Runoff = 3.47 cs @ 12.18 hrs, Volume= 0.274 af, Depth= 7.61" Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs NOAA 24-hrD 100-Year-2050 Rainfall=11.52", P2=4.09" 148,843 70 Woods, Good, HSG.C 18,843 7100.00% Pervious Area & STORMWATER PAVED DRIVEWAY EX CONDITIONS \ 8 Lv ) i s Ean on vee Canacty Description L 4 5 “ ¢ \ min) (feet isec) 2 eet Flow, NEW LOT 28.03 \7 68 100 00370 0.25 Sheet Flow, é i ) Grass: Short n= 0.150 P2= 4.09" V < 41 244 0.0400 1.00 Shallow Concentrated Flow, \> a> Woodland Kv=5.0fps i WD 10.9 344 Total we 2 4 KY fs AM < 20" HIGH SW 27 ARBORVITAE ROW | ua i i} ag oeeee nen aa) | 4 4 ¢ i Rae ta) | EXISTING i jog PROPOSED TWO STORY DWELLING | EXISTING & iss zs; RECONSTRUCTED OVER FOOTPRINT | oF=- 4 =! | ia OF DEMOLISHED DWELLING | || i | LOT 28.02 a FF ELEV = 572.1 Le | EXISTING DWELLING “ye | 1 “| 4 oe | | r | ay Li | | PORCH bof \ \ r) | l a \ ina \ / / 8 CE PERE Pic | — \ g { : JTC PATH \ ' PROPOSED CONDITIONS STUDY LAND USE PLANNING AND SOURCE CONTROL PLAN ; x \ EXISTING ALUMINUM '10.9 minutes § por PAVEMENT PICKET FENCE / __ __ _ __ = yj Pond Outlet Structure Precast E Inlet with weir wall 567.30 Grate 566.50 Top Wall 565.10 5” Orifice 564.50 6” Orifice 563.00 2.5” Orifice 563.00 8” Out Device Routing Invert Qutlet

__ = yj Pond Outlet Structure Precast E Inlet with weir wall 567.30 Grate 566.50 Top Wall 565.10 5” Orifice 564.50 6” Orifice 563.00 2.5” Orifice 563.00 8” Out Device Routing Invert Qutlet Devices S [26°22'00”_w Below Grade Detention System ‘——— Bottom Pond Elev = 563.0 Top Pond Elev = 567.0 (66) 360HD Cultec Storage Chambers BASIN SIZING #1 #2 #3 #4 #5 Discarded Outflow Max=0.04 cfs @ 12.20 hrs HW=566.44' (Free Discharge) Discarded 563.00" Primary Primary Primary Primary 563.00" 564.40" 565.10" 566.95" 0.500 in/hr Exfiltration over Horizontal area Conductivity to Groundwater Elevation = 560.30" 2.5" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads 6.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads 5.0" Vert. Orifice/Grate C= 0.600 Limited to weir flow at low heads 4.0' long x 1.0° breadth Broad-Crested Rectangular Weir Head (feet) 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 250 3.00 Coef. (English) 2.69 2.72 2.75 2.85 2.98 3.08 3.20 3.28 3.31 3.30 3.31 332 |t-4-Exfittration (Controls 0.04 cfs) Primary OutFlow Max=2.26 cfs @ 12.20 hrs HW=566.44" (Free Discharge) /olume Invert___Avail.Storage Storage Description BIA 563.00" 4,582 cf 12.75'Wx 125.50'L x 4.00'H Field A 6,401 cf Overall - 2,444 cf Embedded = 3,956 cf x 40.0% Voids #24 563.50° 2,444 cf Cultec R-360HD x66 Inside #1 Effective Size= 54.9°W x 36.0°H => 9.99 sfx 3.67L = 36.6 of Overall Size= 60.0°W x 36.0°H x 4.17'L with 0.50 Overlap 66 Chambers in 2 Rows Cap Storage= 6.5 cfx 2x2 rows = 25.8 of Storage Group A created with Chamber Wizard 4,027 of Total Available Storage =OrificelGrate (Orifice Controls 0.30 cfs @ 8.79 fps) 3=OrificelGrate (Orifice Controls 1.26 cfs @ 6.44 fps) =OrificelGrate (Orifice Controls 0.70 cfs @ 5.12 fps) Broad-Crested Rectangular Weir ( Controls 0.00 cfs) DRAINAGE AREA BOUNDARY DIRECTED TO THE INFILTRATION SYSTEM (—_—— ) DRAINAGE AREA BOUNDARY BYPASSING INFILTRATION SYSTEM (—_—e ) TC PATH PROPOSED to BASIN 5.0 minutes Runoff = 436 cis@ 12.12hrs, Volume= 0.358 af, Depth=11.28" Routed to Pond 12P : Infiltration Basin Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs NOAA 24-hr D 100-Year-2050 Rainfall=11.52", P2=4.09" Area(sf)_ CN Description : 16,609 98 Impervious to Permeable Pavement 16,509 100.00% Impervious Area Te Length Slope Velocity Capacity

t= 0.01 hrs NOAA 24-hr D 100-Year-2050 Rainfall=11.52", P2=4.09" Area(sf)_ CN Description : 16,609 98 Impervious to Permeable Pavement 16,509 100.00% Impervious Area Te Length Slope Velocity Capacity Description (min) (feet) (fut) _(flisec) (cfs) 50 Direct Entry, O 5’ 10'15’ 20°25’ 50° Runoff == 0.10 cfs@ 12.13hrs, Volume= 0.008 af, Depth=11.28" Routed to Reach 12R : Point of Study Inlet at Rear of Lot 21.01 Runoff by SCS TR-20 method, UH=SCS, Weighted-CN, Time Span= 0.00-48.00 hrs, dt= 0.01 hrs INOAA 24-hrD 100-Year-2050 Rainfall=11.52", P2=4.09" Area(sf) CN Description 38498 Misc Impervious To Rear Property 384 100.00% Impervious Area Te Length Slope Velocity Capacity Description (min) (feet) __(fut)_(fsec) (cfs) 58 65 0.0600 0.19 Sheet Flow, Grass: Dense n=0.240 P2= 4.09" 100’ GRAPHIC SCALE 4°=20) \ ire HIGH POINT N 65°20’50” W 528.66" LAND _USE PLANNING DISCUSSION The total area of land disturbance is 1.10 Acres In accordance with the goals and standards of Chapter 25—29.3 through 25—29.5 of the West Orange Code this plan has been developed in the following manner. The project construction shall conform to a Soil Erosion and Sediment Contol Plan, to be reviewed and approved by the Conservation District. Green Infrastucture has been implemented into the design through use of permeable pavement systems which collect, store and direct runoff towards an infiltration basin, providing water quality, recharge and volume reduction. Additionally low impact development measures are implemented throughout the unstudied portion of the project which will lessen the overall stormwater runoff from the site to a greater extent. The measures include; preservation of large decidous trees along the site perimeter, lessening of slopes in the rear yard of proposed homes and increasing drainage path routes in order to increase time of concentration. MAJOR STORMWATER DESIGN JUSTIFICATION To ensure that the design complies with the requirements and goals of the Township Stormwater Ordinance a detailed analysis of the site condition was performed. A soils evaluator tested various areas of the site to identify both seasonal high water levels and the ability of the soil to infiltrate runoff. Additionally areas allowing for use of low impact development were identified; including potential preservation of large deciduous TABLE OF BMP INFORMATION trees,

y of the soil to infiltrate runoff. Additionally areas allowing for use of low impact development were identified; including potential preservation of large deciduous TABLE OF BMP INFORMATION trees, lessening the slope of surfaces and elongation of drainage paths. This study focused the design on the area of the site which would allow for use of infiltration. 9 F208 MANAGEMENT FACILITIES MAP Revision Table: 2) TOWNSHIP ZONING/ENGINEERING REVIEW 04-13-26 1) UPDATE FOR NEW HOUSE PLAN 01-06-2026 0) INITIAL ISSUE 11-25-2025 WA VEL WILLIAM S. Professional Enghieer, COTT, P.E. NJ. License N6. GE44863 (Sy Qa NANCY J. SCOTT, P.L.S. A small scale sub-surface extended detention infiltration basin (a system allowing for infiltration and controlled release) was chosen as the green infrastructure BMP to provide infiltration, recharge and reduction BOTTOM S.H.W. INFILTRATION Professional Land Surveyor BMP DESCRIPTION ELEVATION ELEVATION RATE "/HR NJ. License No. GS35875 INFILTRATION BASIN 563.0 560.3 1.00 - PERMABLE PAVEMENT 566.5 560.3/561.0| N/A of runoff quantity. The basin is located at the area of the site where the soils evaluation determined an acceptable infiltration rate for design (A factor of safety was applied to the analysis by utilizing 1 of the measured infiltration rate in all calculations). The basin shall be a shared system, accepting runoff from both lots, therefore an easement allowing for common use and maintenance shall be established. Operations and maintenance requirements and responsibilities shall be filed with the record owner deeds. Permeable pavement, another green infrastructure BMP, is specified for all driveway surfaces. This system is rated for 80% total suspended solids reduction providing water quality treatment for the site. The analysis shows that the runoff from the developed portion of the site directed towards the infiltration basin when combined with the runoff rate from the developed portions of the site which bypass the system, has been reduced to no more than 50% of the two year storm rate, 75% of the 10 year storm rate and 80% of the 100 year storm rate from what would have occurred if the design area were an undeveloped wooded lot when measured at the point at which runoff would leave the site. In addition to the utilization of two green infrastructure BMPs low impact development measures are

rea were an undeveloped wooded lot when measured at the point at which runoff would leave the site. In addition to the utilization of two green infrastructure BMPs low impact development measures are implemented throughout the unstudied portion of the site (not experiencing placement of impervious cover and maintaining existing lawn surfaces) which will serve to lessen the overall stormwater runoff from the site. These measures include; preservation of large trees, lessening of slopes and increasing drainage paths to increase time of concentration. These items are shown on the Land Use Planning and Source Control Plan within the site plan set. ENSURPLAN INC. (Certificate of Authorization No. 24GA27997700) P.O. BOX 4304, WARREN, N.J. 07059 Tel: 732-469-0400 ensurplan@gmail.com LAND USE PLANNING AND SOURCE CONTROL STORMWATER MANAGEMENT FACILITIES MAP 15 RIDGEWAY AVENUE LOT 28.01 (TAX. MAP IN BLOCK 158 SHEET NO. 91) SITUATED IN THE TWP. OF WEST ORANGE, ESSEX COUNTY, Nu SCALE: 1”=20’ ORDER: E-11156 6 DATE: 11-25-2025 FILE: 29906 7