control of the hydrology, to which the calibration
metrics are quite responsive, and that k 2 has a
greater impact on the hydrology in terms of
volumes of water.
3.2 Pre-construction Simulation
A separate set of simulations shows how the
reservoirs would have worked with rainfall conditions prior to 2011, i.e. as if the reservoirs had
been constructed earlier. This analysis allows to
assess how much of the reservoirs’ poor performance may be linked to the perceived change in
climate conditions (see on ‘weather data’ above).
Some of the markedly wet years (i.e. 2003, 2010)
would have resulted in significantly higher water
volumes, V R , in the reservoirs (Fig. 10). Although
not quite reaching full capacity, V Rmax , these
higher volumes persist for several months before
evaporating during the summer. This gives hope
that the reservoirs can function to a higher capacity
in future years with higher rainfall. However, there
also are several years with negligible contribution
Fig. 10 Pre-construction rainfall (a) and associated hypothetical performance of reservoirs 1B (b) and 1A (c). The
dashed line indicates the approximate construction of the reservoir
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