Water Sensitive SA

Tips – InSite Water tool

Design tips
Tip 1 – Check rainwater tank performance over time with a daily time step tank volume graph

The Water tank performance over time graph provides a quick visual guide as to whether the roof catchment area, connected rainwater uses (demand) and the retention/detention tank storage volume combination provides the desired design performance, e.g. flood management, rainwater harvesting and reuse and therefore represents good value for money.

Good retention/detention tank performance
Water tank performance over time - good

In the tool you can drag the curser over a section of the graph to zoom in and view the weekly average water tank performance

Water tank reliability and rainwater tank overflow - good

Poor retention/detention tank performance
Water tank performance over time - poor

The tank is performing poorly as a downstream flooding prevention device, a sit is usually overflowing.

Water tank reliability and rainwater tank overflow - poor

To improve performance – increase tank water demand (uses inside the home, preferably) and/or increase tank size to reduce overflow.

Have a look at our InSite Water Tool web page to find out more.

Tip 2 - How to model detention in the InSite Water Tool

Did you know there are two ways to model detention storage using the InSite Water tool?
Example | 6 townhouses


METHOD 1. Detention storage associated with direct rainwater runoff from roofs.

InSite Water Tip 2 - Projects

InSite Water Tip 2 - Specify stormwater runoff and management solutions

If this does not provide enough detention for the site, the results will indicate the additional storage requirements.

InSite Water Tip 2 - Results


METHOD 2: Detention storage associated with combined roof and surface runoff

InSite Water Tip 2 - Site storage design

Updated results with additional detention storage

InSite Water Tip 2 - Results-2


Tip 3 – Accounting for the local drainage system capacity

InSite Water provides for addition of the “Stormwater design” details of any project on the second page of the website.

Scrolling down to “Local catchment details” there is a drop-down menu to select the best description for the existing development under “Local drainage system capacity”. The land use and lot size is an indicator of the likely capacity of the local drainage system. Each has a corresponding default value as per the table below.

InSite Water tools' Local catchment details

InSIte Water tool - local drainage system capacity corresponding default value


Acknowledgement of Country

Water Sensitive SA acknowledges Aboriginal people as the First Peoples and Nations of the lands and waters we live and work upon, and we pay our respects to their Elders past, present and emerging. We acknowledge and respect the deep spiritual connection and the relationship that Aboriginal and Torres Strait Islander people have to Country.