Low flows
The low flow rate was identified by assessing the flow of water required
to turn over the entire volume of water in an average permanent pool in
five days. Five days was selected as this was a reasonable approximation
of the flow duration of a pulse flow in response to a large summer storm
based on the observed data. Pool volumes were estimated using a simple
ellipsoid formula with length and width estimated from aerial imagery
and depth based on data collected during previous surveys
(unpub. data, Schmarr et al., 2014). The
PWRA was divided into four areas based on understanding of the runoff
generation and watercourse characteristics across the landscape as well
as the location of key monitoring stations (Penrice for the Flaxman and
Yaldara for the Barossa) (Hancock et al.,
2014). The flow rate at the end of each of these areas was defined
based on the flow rate required to turn over pools in the upstream area.
Each of the individual management zones in each area were given a flow
rate based on its proportion of the total catchment.