07/1841 - Response to Information Request [As Published] · 132007.1841

STORMWATER MANAGEMENT PLAN 6

 

5.0 Pre-Development Flows

5.1 Rationale

The proposed site is currently undeveloped, and therefore an impervious area of 0% was used.
As the majority of the site contains no identifiable watercourses of concentrated overland
flow, it is assumed that the pre development overland flow occurs as sheet flow. The pre-
development model was set up so as that the stormwater runoff will drain to the north-eastern

environmental drainage area of the site.

The peak flows for the pre development conditions were derived using a conservative method

by utilising only the XP-STORM model hydrologic runoff layer.

5.2 Results

The peak flows for the pre development conditions are indicated in Table 5.1.

Table 5.1: Pre development Peak Flows
ARI Design Storm (min) Peak Flow (m°/s)

10 25 0.811
100 25 0.120

 

 

 

 

 

 

 

 

XP-STORM pre development model output is included in Appendix B.

 

BARLOW GREGG VOM M3048
DECEMBER 2007