NOTE: The definition of major development above aligns with
the definition at N.J.A.C. 7:8-1.2 and is recommended for consistency.
Alternatively, a municipality may adopt the following definition,
which is the minimum standard required. Municipalities that have already
adopted the definition at N.J.A.C. 7:8-1.2 or another definition that
goes beyond the minimum requirement should not reduce the stringency
of their definition by adopting the minimum standard.
|
Table 1
Green Infrastructure BMPs for Groundwater Recharge, Stormwater
Runoff Quality, and/or Stormwater Runoff Quantity
| ||||
---|---|---|---|---|
Best Management Practice
|
Stormwater Runoff Quality TSS Removal Rate
(percent)
|
Stormwater Runoff Quantity
|
Groundwater Recharge
|
Minimum Separation from Seasonal High Water Table
(feet)
|
Cistern
|
0
|
Yes
|
No
|
—
|
Dry well(a)
|
0
|
No
|
Yes
|
2
|
Grass swale
|
50 or less
|
No
|
No
|
2(e)
1(f)
|
Green roof
|
0
|
Yes
|
No
|
—
|
Manufactured treatment device(a), (g)
|
50 or 80
|
No
|
No
|
Dependent upon the device
|
Pervious paving system(a)
|
80
|
Yes
|
Yes(b)
No(c)
|
2(b)
1(c)
|
Small-scale bioretention basin(a)
|
80 or 90
|
Yes
|
Yes(b)
No(c)
|
2(b)
1(c)
|
Small-scale infiltration basin(a)
|
80
|
Yes
|
Yes
|
2
|
Small-scale sand filter
|
80
|
Yes
|
Yes
|
2
|
Vegetative filter strip
|
60 to 80
|
No
|
No
|
—
|
(Notes corresponding to annotations(a) through (g) are found following Table
3.)
|
Table 2
Green Infrastructure BMPs for Stormwater Runoff Quantity (or
for Groundwater Recharge and/or Stormwater Runoff Quality
| ||||
---|---|---|---|---|
Best Management Practice
|
Stormwater Runoff Quality TSS Removal Rate
(percent)
|
Stormwater Runoff Quantity
|
Groundwater Recharge
|
Minimum Separation from Seasonal High Water Table
(feet)
|
Bioretention system
|
80 or 90
|
Yes
|
Yes(b)
No(c)
|
2(b)
1(c)
|
Infiltration basin
|
80
|
Yes
|
Yes
|
2
|
Sand filter(b)
|
80
|
Yes
|
Yes
|
2
|
Standard constructed wetland
|
90
|
Yes
|
No
|
N/A
|
Wet pond(d)
|
50 to 90
|
Yes
|
No
|
N/A
|
(Notes corresponding to annotations (b) through (d) are found following Table
3.)
|
Table 3
BMPs for Groundwater Recharge, Stormwater Runoff Quality, and/or
Stormwater Runoff Quantity only with a Waiver or Variance from N.J.A.C.
7:8-5.3
| ||||
---|---|---|---|---|
Best Management Practice
|
Stormwater Runoff Quality TSS Removal Rate
(percent)
|
Stormwater Runoff Quantity
|
Groundwater Recharge
|
Minimum Separation from Seasonal High Water Table
(feet)
|
Blue roof
|
0
|
Yes
|
No
|
N/A
|
Extended detention basin
|
40 to 60
|
Yes
|
No
|
1
|
Manufactured treatment device(h)
|
50 or 80
|
No
|
No
|
Dependent upon the device
|
Sand filter(c)
|
80
|
Yes
|
No
|
1
|
Subsurface gravel wetland
|
90
|
No
|
No
|
1
|
Wet pond
|
50 to 90
|
Yes
|
No
|
N/A
|
Notes to Tables 1, 2, and 3:
| |
---|---|
(a)
|
Subject to the applicable contributory drainage area limitation specified at § 111-30O(2).
|
(b)
|
Designed to infiltrate into the subsoil.
|
(c)
|
Designed with underdrains.
|
(d)
|
Designed to maintain at least a ten-foot wide area of native
vegetation along at least 50% of the shoreline and to include a stormwater
runoff retention component designed to capture stormwater runoff for
beneficial reuse, such as irrigation.
|
(e)
|
Designed with a slope of less than 2%.
|
(f)
|
Designed with a slope of equal to or greater than 2%.
|
(g)
|
Manufactured treatment devices that meet the definition of "green infrastructure" at § 111-28.
|
(h)
|
Manufactured treatment devices that do not meet the definition of "green infrastructure" at § 111-28.
|
Best Management Practice
|
Maximum Contributory Drainage Area
|
---|---|
Dry well
|
1 acre
|
Manufactured treatment device
|
2.5 acres
|
Pervious pavement systems
|
Area of additional inflow cannot exceed three times the area
occupied by the BMP
|
Small-scale bioretention systems
|
2.5 acres
|
Small-scale infiltration basin
|
2.5 acres
|
Small-scale sand filter
|
2.5 acres
|
Table 4 - Water Quality Design Storm Distribution
| |||||
---|---|---|---|---|---|
Time
(Minutes)
|
Cumulative Rainfall
(Inches)
|
Time
(Minutes)
|
Cumulative Rainfall
(Inches)
|
Time
(Minutes)
|
Cumulative Rainfall
(Inches)
|
1
|
0.00166
|
41
|
0.1728
|
81
|
1.0906
|
2
|
0.00332
|
42
|
0.1796
|
82
|
1.0972
|
3
|
0.00498
|
43
|
0.1864
|
83
|
1.1038
|
4
|
0.00664
|
44
|
0.1932
|
84
|
1.1104
|
5
|
0.00830
|
45
|
0.2000
|
85
|
1.1170
|
6
|
0.00996
|
46
|
0.2117
|
86
|
1.1236
|
7
|
0.01162
|
47
|
0.2233
|
87
|
1.1302
|
8
|
0.01328
|
48
|
0.2350
|
88
|
1.1368
|
9
|
0.01494
|
49
|
0.2466
|
89
|
1.1434
|
10
|
0.01660
|
50
|
0.2583
|
90
|
1.1500
|
11
|
0.01828
|
51
|
0.2783
|
91
|
1.1550
|
12
|
0.01996
|
52
|
0.2983
|
92
|
1.1600
|
13
|
0.02164
|
53
|
0.3183
|
93
|
1.1650
|
14
|
0.02332
|
54
|
0.3383
|
94
|
1.1700
|
15
|
0.02500
|
55
|
0.3583
|
95
|
1.1750
|
16
|
0.03000
|
56
|
0.4116
|
961
|
1.1800
|
17
|
0.03500
|
57
|
0.4650
|
97
|
1.1850
|
18
|
0.04000
|
58
|
0.5183
|
98
|
1.1900
|
19
|
0.04500
|
59
|
0.5717
|
99
|
1.1950
|
20
|
0.05000
|
60
|
0.6250
|
100
|
1.2000
|
21
|
0.05500
|
61
|
0.6783
|
101
|
1.2050
|
22
|
0.06000
|
62
|
0.7317
|
102
|
1.2100
|
23
|
0.06500
|
63
|
0.7850
|
103
|
1.2150
|
24
|
0.07000
|
64
|
0.8384
|
104
|
1.2200
|
25
|
0.07500
|
65
|
0.8917
|
105
|
1.2250
|
26
|
0.08000
|
66
|
0.9117
|
106
|
1.2267
|
27
|
0.08500
|
67
|
0.9317
|
107
|
1.2284
|
28
|
0.09000
|
68
|
0.9517
|
108
|
1.2300
|
29
|
0.09500
|
69
|
0.9717
|
109
|
1.2317
|
30
|
0.10000
|
70
|
0.9917
|
110
|
1.2334
|
31
|
0.10660
|
71
|
1.0034
|
111
|
1.2351
|
32
|
0.11320
|
72
|
1.0150
|
112
|
1.2367
|
33
|
0.11980
|
73
|
1.0267
|
113
|
1.2384
|
34
|
0.12640
|
74
|
1.0383
|
114
|
1.2400
|
35
|
0.13300
|
75
|
1.0500
|
115
|
1.2417
|
36
|
0.13960
|
76
|
1.0568
|
116
|
1.2434
|
37
|
0.14620
|
77
|
1.0636
|
117
|
1.2450
|
38
|
0.15280
|
78
|
1.0704
|
118
|
1.2467
|
39
|
0.15940
|
79
|
1.0772
|
119
|
1.2483
|
40
|
0.16600
|
80
|
1.0840
|
120
|
1.2500
|
R = A + B - (A x B)/100
| ||
Where:
| ||
R
|
=
|
total TSS Percent Load Removal from application of both BMPs;
and
|
A
|
=
|
the TSS Percent Removal Rate applicable to the first BMP.
|
B
|
=
|
the TSS Percent Removal Rate applicable to the second BMP.
|
Table 5: Current Precipitation Adjustment Factors
| |||
---|---|---|---|
Current Precipitation Adjustment Factors
| |||
County
|
2-year Design Storm
|
10-year Design Storm
|
100-year Design Storm
|
Atlantic
|
1.01
|
1.02
|
1.03
|
Bergen
|
1.01
|
1.03
|
1.06
|
Burlington
|
0.99
|
1.01
|
1.04
|
Camden
|
1.03
|
1.04
|
1.05
|
Cape May
|
1.03
|
1.03
|
1.04
|
Cumberland
|
1.03
|
1.03
|
1.01
|
Essex
|
1.01
|
1.03
|
1.06
|
Gloucester
|
1.05
|
1.06
|
1.06
|
Hudson
|
1.03
|
1.05
|
1.09
|
Hunterdon
|
1.02
|
1.05
|
1.13
|
Mercer
|
1.01
|
1.02
|
1.04
|
Middlesex
|
1.00
|
1.01
|
1.03
|
Monmouth
|
1.00
|
1.01
|
1.02
|
Morris
|
1.01
|
1.03
|
1.06
|
Ocean
|
1.00
|
1.01
|
1.03
|
Passaic
|
1.00
|
1.02
|
1.05
|
Salem
|
1.02
|
1.03
|
1.03
|
Somerset
|
1.00
|
1.03
|
1.09
|
Sussex
|
1.03
|
1.04
|
1.07
|
Union
|
1.01
|
1.03
|
1.06
|
Warren
|
1.02
|
1.07
|
1.15
|
Table 6: Future Precipitation Change Factors
| |||
---|---|---|---|
Future Precipitation Change Factors
| |||
County
|
2-year Design Storm
|
10-year Design Storm
|
100-year Design Storm
|
Atlantic
|
1.22
|
1.24
|
1.39
|
Bergen
|
1.20
|
1.23
|
1.37
|
Burlington
|
1.17
|
1.18
|
1.32
|
Camden
|
1.18
|
1.22
|
1.39
|
Cape May
|
1.21
|
1.24
|
1.32
|
Cumberland
|
1.20
|
1.21
|
1.39
|
Essex
|
1.19
|
1.22
|
1.33
|
Gloucester
|
1.19
|
1.23
|
1.41
|
Hudson
|
1.19
|
1.19
|
1.23
|
Hunterdon
|
1.19
|
1.23
|
1.42
|
Mercer
|
1.16
|
1.17
|
1.36
|
Middlesex
|
1.19
|
1.21
|
1.33
|
Monmouth
|
1.19
|
1.19
|
1.26
|
Morris
|
1.23
|
1.28
|
1.46
|
Ocean
|
1.18
|
1.19
|
1.24
|
Passaic
|
1.21
|
1.27
|
1.50
|
Salem
|
1.20
|
1.23
|
1.32
|
Somerset
|
1.19
|
1.24
|
1.48
|
Sussex
|
1.24
|
1.29
|
1.50
|
Union
|
1.20
|
1.23
|
1.35
|
Warren
|
1.20
|
1.25
|
1.37
|