Wisconsin Administrative Code
Department of Natural Resources
NR 100-199 - Environmental Protection General
Chapter NR 151 - Runoff Management
Subchapter IV - Transportation Facility Performance Standards
Section NR 151.243 - Peak discharge performance standard
Current through August 26, 2024
(1) REQUIREMENT. By design, BMPs shall be employed to maintain or reduce the 1-year, 24-hour and the 2-year, 24-hour post-construction peak runoff discharge rates to the 1-year, 24-hour and the 2-year, 24-hour pre-development peak runoff discharge rates respectively, or to the maximum extent practicable. The runoff curve numbers in Table 2. shall be used to represent the actual pre-development condition.
Table 2. Maximum Pre-Development Runoff Curve Numbers |
||||
Runoff Curve Number |
Hydrologic Soil Group |
|||
A |
B |
C |
D |
|
Woodland |
30 |
55 |
70 |
77 |
Grassland |
39 |
61 |
71 |
78 |
Cropland |
55 |
69 |
78 |
83 |
Note: Where the pre-development condition is a combination of woodland, grassland, or cropland, the runoff curve number should be pro-rated by area.
(2) EXEMPTIONS. This section does not apply to the following:
The intent of s. NR 151.243 is to minimize streambank and shoreline erosion under bank-full conditions.