For the third scenario, scenario 2 pumpage was used
except that pumpage was reduced by 10 percent from that
of scenario 2 in a selected area (fig. 25 in report) to represent
possible replacement of ground water by surface-water
diversion (U.S. Army Corps of Engineers, written commun., 2002)
in that area. The 10 percent reduction was applied only to the
stress periods ending in years 2019, 2029, 2039, and 2049.
Reducing pumpage by 10 percent (scenario 3) resulted in areas of depressed
simulated hydraulic heads similar to those that resulted from scenario 2 and
fewer dry cells (figs. 20 and 23 in report). In the 2019 timeframes,
scenario 3 (fig. 20 in report) had 3 dry cells compared with scenario 2,
which had 10 dry cells (fig. 20 in report). In the remaining three timeframes
(2029, 2039, and 2049), scenario 3 (fig. 20 in report) had about two-thirds of
the number of dry cells of that in scenario 2. The 10 percent reduction
appears to have delayed the development of dry cells by about 10 years
as exhibited by the similarities of water levels and dry cells in the
2029, scenario 2 (fig. 23 in report) and the 2039, scenario 3 (fig. 26 in report).
Overall, the areas of depressed simulated hydraulic heads are somewhat
reduced in this scenario from that using unreduced pumpage (scenario 2).