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., - ii-a ;~mpare the s~-aso~~lwi1t~~-level changes to th~ long-=-term wate;:--lev~l1 changes, a simulation was made with monthly time intervi1ls. The monthly re-! , charge computed by the distribution model (table 5) for the median diversions i using the canal configuration having all canals and 65 ponds was repeated for I 27 years, The estimated current pumping was distributed monthly according to! a_typical potential evapotranspiration curve for this area (Hurr and others, I 1975, fig. 11). The resulting net stress on the aquifer is shown in table ]3, I During the twenty-seventh year, Wi1ter levels (table 13) were approximately i1t ! the same level as predicted by the annual time-increment simulation I (fig. 36). Seasoni1] fluctuation ranged between 0.4 and 3,0 ft at the six: wells monitored during simulation, The monthly streamflO\'I in Beaver Creek i (table 13) ranged from 4.8 ft3/s in September to 15.0 ft3/s in Apri 1. The' average of these monthly streamfl0\1 values corresponds closely to the stream- : flow for the twenty-seventh year with the simulation using the annual time i intervals, although both values are noticeably less than the final steady- I state values (table 12). I The effects of recharge greater than that occurring with median di-, versions were simulated using the 27 years of historically developed data I (table 9). Using the same monthly time interval and estimated monthly pumping' as the previous simulation, monthly recharge computed by the canal-distribu- ' tion model was input into the ground-water model for 27 years. The net stress (artificial recharge less pumping) for the 27 years is shown in figure 37. The response of the aquifer system, indicated in figures 38-41, is compared to the responses when simulated \1ith median-diversion recharge. Although the canal-distribution model indicated no problems in soil infiltration during, the 27 years of historically developed diversions, the ground-water model did. Through the first 10 years of simulation there are intermittent periods in which water levels in the sand hill areas approach land surface. The large recharge during the eleventh year, hO\1ever, raises water levels throughout the sand hill areas above land surface (recall that the recharge values computed by the canal-distribution model and evapotranspiration rates are not modified by the ground-water model as areas become waterlogged), Throughout the remainder of the 27-year simulation period, most of the sand hi 11 area east of the recharge ditches has water levels above the land surface. I I I I I " &.5