HomeMy WebLinkAboutCHERRY STREET COTTAGES - PDP - PDP160041 - SUBMITTAL DOCUMENTS - ROUND 2 - STORMWATER-RELATED DOCUMENTS (17)17-06-02_2-yr peak runoff_UD-Rational_Revised.xls, Intro 6/6/17, 8:33 AM
Purpose: This workbook applies the Rational Method to estimate stormwater
runoff and peak flows from small urban catchments,
i.e., typically less than 90 acres.
Function: 1. To apply the area-weighting method to calculate the representative
runoff coefficient C for a catchment.
2. To calculate the time of concentration, and then compare with
the empirical time of concentration limit used for the Denver region.
The smaller one is recommended as the rainfall duration for
use with the Rational Method.
3. To calculate the design rainfall intensity and peak flow rate.
Content: The workbook consists of the following five sheets:
Intro Describes the purpose of each sheet in the workbook.
Weighted C Applies the area-weighting method to determine the runoff C.
Tc and PeakQ Calculates Tc and Q-peak.
Design Info Provides the recommended runoff C's for various land uses.
Notation Defines the variables used.
Acknowledgements: Spreadsheet Development Team:
Dr. James C.Y. Guo, P.E.
Professor, Department of Civil Engineering
University of Colorado at Denver
Ken A. MacKenzie, P.E.
Urban Drainage and Flood Control District
Wright Water Engineers, Inc.
Denver, Colorado
Comments? Direct all comments regarding this spreadsheet workbook to: UDFCD E-Mail
Revisions? Check for revised versions of this or any other workbook at: Downloads
PEAK RUNOFF PREDICTION BY THE RATIONAL METHOD
Denver, Colorado
Urban Drainage and Flood Control District
Version 1.02a, Released August 2005