Table 1. TSS Reduction Standards
| |
---|---|
Development Type
|
TSS Reduction
|
New Development
|
80%
|
In-fill development
|
80%
|
Redevelopment
|
40% of load from parking areas and roads
|
Table 2. Maximum Pre-Development Runoff Curve Numbers
| ||||
---|---|---|---|---|
Hydrologic Soil Group
| ||||
Runoff Curve Number
|
A
|
B
|
C
|
D
|
Woodland
|
30
|
55
|
70
|
77
|
Grassland
|
39
|
61
|
71
|
78
|
Cropland
|
55
|
69
|
78
|
83
|
Table 3. Separation Distances and Soil Characteristics
| ||
---|---|---|
Source Area
|
Separation Distance
|
Soil Characteristics
|
Industrial, Commercial, Institutional Parking Lots and Roads
|
5 feet or more
|
Filtering Layer
|
Residential Arterial Roads
|
5 feet or more
|
Filtering Layer
|
Roofs Draining to Subsurface Infiltration Practices
|
1 foot or more
|
Native or Engineered Soil with Particles Finer than Coarse Sand
|
Roofs Draining to Surface Infiltration Practices
|
Not Applicable
|
Not Applicable
|
All Other Impervious Source Areas
|
3 feet or more
|
Filtering Layer
|