Stormwater & Drainage Calculations

Use:

• NAVD 1988
• NOAA Atlas 14 Point Precipitation Frequency Estimates: MN
• MPCA Stormwater Manual
• MPCA Stormwater Manual Table of Contents
• MPCA MIDS calculator page (Minimal Impact Design Standards)

We have an XPSWMM model that covers the entire District. A Nested Distribution or MSE-3 distribution should be used instead of Type-II storm type.

• A Nested Distribution can be generated in HydroCAD by following these steps for implementing Atlas 14 into Hydrocad.
• MSE-3 rainfall distribution is available in HydroCAD v10, build 16 or greater.
• Stormwater_Management_Example_Tables_and_Guidance.pdf
• stormwater_management_example_blank_tables.xlsx