*4.5. Whole-of-Life Modelling*

Figure 10 shows the recharge response to a whole-of-lifetime sequence for irrigation areas. The results show that time delays for new developments increase for decreasing *Ks*2*v*. The highest value of *Ks*2*<sup>v</sup>* (01.1 mm/day) produces the earliest and highest peak value, equalling *IA* after five years. For other values of *Ks*2*v*, the peak values occur later and have lower values, with the lowest value of *Ks*2*<sup>v</sup>* (0.01 mm/day) having a barely discernible peak. For *Ks2v* = 0.1 mm/day, the shape mirror that of *IA,* but with a delay varying from 3 to 8 years. For the next highest value of *Ks*2*v*, 0.05 mm/day, recharge reduces exponentially until there is no perched head and then falls to match the recharge for 0.1 mm/day. For the third highest value of *Ks*2*v*, 0.03 mm/day, recharge also falls, more or less, exponentially (but more slowly than for *Ks*2*<sup>v</sup>* = 0.05 mm/day), to where the perched water disappears and then falls to the final value only two years after the previous curves, and with a time delay of up to twelve years after *IA*. Reduction of *Ks*2*<sup>v</sup>* and the presence of perched water leads to lower peak recharge values, greater time delays. When perched water disappears, the difference between the recharge disappears.
