Recharge map of Australia using Method of Last Resort.
Recharge-Discharge Estimation Suite: a nationally consistent approach to recharge and discharge estimation in data poor areas
The Recharge-Discharge Estimation software suite provides water managers with valuable tools to estimate groundwater recharge and/or discharge in areas where no field based recharge or discharge studies have been undertaken.
9 November 2011 | Updated 21 June 2013
In this article
The Recharge-Discharge Estimation Suite provides estimates for areas where no field based recharge or discharge studies have been undertaken.
The Recharge-Discharge Estimation Suite is a valuable tool for water managers.
It is comprised of two stand-alone tools in the Microsoft Excel™ spreadsheet format, coupled with a complimentary web-based national-scale spatial dataset produced by collaborative project partners Geoscience Australia, and provides recharge and discharge estimates using simple approximations with data that is usually readily available and/or accessible.
The recharge tool uses a decision-tree methodology that is implemented in the spreadsheet. It incorporates various parameters such as:
- average annual rainfall
- soil/regolith and vegetation type
- land use change
- rainfall chloride flux
- groundwater chloride concentration.
The discharge tool uses a soil water balance approach decision-tree to estimate groundwater discharge and is implemented in a spreadsheet.
It incorporates knowledge of the soil profile and regolith down to the water table depth as well as parameters such as:
- rainfall, evaporation
- leaf area index
- depth to water table
- groundwater salinity.
The Recharge-Discharge Estimation tools provide:
- up to three recharge and three discharge estimates at each site
- a 95 per cent confidence interval for most recharge estimates
- a consistent approach to recharge estimates that are applicable to 85 per cent of Australia
- ten specifically derived national-scale spatial datasets, including vegetation, soil and rainfall.
The Recharge-Discharge Estimation Suite is an outcome of a National Water Commission project 'A Consistent Approach to Groundwater Recharge Determination in Data Poor Areas', carried out by the Water for a Healthy Country Flagship and Geoscience Australia.
Find out more
There are two companion reports to the recharge and discharge spreadsheets. The Scientific Reference Guide details the supporting science that underpins the relationships and methods used in the estimation spreadsheets. It is currently being reviewed and will be available shortly. The User Guide provides direction to users on when to use the groundwater recharge and discharge estimation tools and how to populate them. In addition, users are directed to the Geoscience Australia MapConnect website, in particular the Groundwater Theme that has been specifically created as a web-based data delivery system for the various national scale datasets required to populate the tools.
Go to the MapConnect website. [external link]
Read the Recharge-Discharge Estimation Suite terms of agreement and download the software.
Download the User Guide [PDF 4.5MB]
Please note that there are limitations associated with the use of these spreadsheets which include the:
- spreadsheets should only be used in data poor areas where the value of the groundwater resource does not warrant field studies
- spreadsheets should not be used in irrigation areas because the methods do not account for the added difficulties associated with the wide range of crops and irrigation management
- spreadsheets should not be used to estimate river recharge as they do not account for the complex surface water-groundwater interactions associated with this form of recharge
- approach contained in the spreadsheets is specific to diffuse recharge and as such it should not be used in areas where preferential/localised recharge, due to surface water flow being a major part of the groundwater balance, is the dominant form of recharge
- discharge estimations only consider evapotranspiration and do not include discharge to rivers, wetlands and the ocean.
Read the Recharge-Discharge Estimation Suite terms of agreement and download.