Perth
10.4 Recharge from surface water

Supporting Information

a. Groundwater models

The Department of Water use the Perth Regional Aquifer Modelling System (PRAMS) Version 3.4 and Peel–Harvey Regional Aquifer Modelling System (PHRAMS) to estimate the natural water movement to and from the groundwater store within the Perth region.

As shown in the following figure, PRAMS estimates groundwater movement for the area north of Mandurah. PHRAMS estimates groundwater movement for the Peel–Harvey area south of Mandurah. The volumes reported in this account refer to the natural water movement that occurs within each model area within the Perth region boundary.


Map of groundwater model areas relative to the Perth region boundary
Map of groundwater model areas relative to the Perth region boundary

b. Supporting Information

This volume represents the groundwater recharge from drains, rivers and storages within the Perth region.

Quantification Approach

Data Source

Department of Water: PRAMS Version 3.4 and PHRAMS groundwater models.

Provided by

Department of Water.

Method

Groundwater recharge was estimated for the Perth region using PRAMS and PHRAMS. However, the estimated groundwater recharge from surface water is zero for both model areas.

Assumptions, Limitations, Caveats and Approximations

Both models assume that all flows between the groundwater store and rivers and drains comes from the aquifers, hence recharge from surface water is zero. This assumption is consistent with measured and simulated discharges. Wetlands were considered to be part of the water table aquifer, hence any groundwater recharge from wetlands was not considered.

Both models were initially developed for the purpose of estimating and assessing the impacts of changes in climatic conditions and varying extraction rates on the aquifers, not for the purposes of preparing water accounts. These models have since been modified to also provide data for water accounting.

Uncertainty Information

The uncertainty estimate was not quantified.

Comparative year

The following table presents substantive changes in the line item reported in this 2011 Account with the corresponding line item in the 2010 Account.


Comparative year information for line item 10.4

2011 Account line item

2010 Account line item

2011 Account volume for the 2009–10 year (ML)

2010 Account volume for the 2009–10 year (ML)

Change from the 2010 Account to the 2011 Account

10.4 Recharge from surface water

15.2.2 Groundwater recharge from connected surface water

0

0

Change in line item name and number