Adelaide

The value reported in the water accounting statement (72,148 ML) represents baseflow to major rivers in the Adelaide region.

Data source

South Australian Department for Water: Hydstra database

Draft Water Allocation Plan for the Western Mount Lofty Ranges (AMLRNRMB 2010).

Data provider

South Australian Department for Water.

Method

Groundwater discharge to connected surface water was estimated from the annual baseflow figures stated in the Draft Water Allocation Plan for the Western Mount Lofty Ranges. The stream gauge for the North Para River at Yaldara (A5050502) was deemed the only streamflow site with a significant baseflow component outside the draft Western Mount Lofty Ranges prescribed water resource area . Baseflow was calculated for this site using a Lyne and Hollick filter (Grayson et al. 1996) with a filtering factor of 0.925 and daily flow records for the period 1 July 1975 to 30 June 2010.

Uncertainty

Ungraded.

Assumptions, approximations and caveats/limitations

• Baseflow at the gauging stations captured all the surface water–groundwater interactions in the catchment.
• Baseflow identified by the Lyne and Hollick filter was entirely due to contributions from groundwater.
• Long-term baseflow represents the flux during 2009–10.
• Groundwater discharge to connected surface water was the dominant process in the Western Mount Lofty Ranges.
• Surface water–groundwater interactions outside the draft Western Mount Lofty Ranges prescribed water resource area and the catchment for Yaldara gauge are negligible.