Laserfiche WebLink
<br />t,' <br /> <br />in Table 3, indicates the significance of lower water levels. <br />The data shown on Figure 2 are from controlled tank conditions where the <br />water level was maintained at 36 inches and not allowed to fluctullte. Many <br />of the reported phreatophyte rat'es are based on such experiments and care <br />needs to be exercised in their application. <br />A third effect that IIU1St be watched for is the lowering of water levels <br />frcm nearby pumping irrigation wells. A number of such wells are shown on <br />Plate 1. <br />The effects of irrigation pumping, from Shelton wells numbered 2, 3, 5 <br />and 6 and a well in Section 30 (caa) , on water levels in Area A during the <br />growing season were examined. Drawdown under Area A by pumping fran these <br />wells was computed by the Theis non-equilibrilUll fornula (9),. without conSi- <br />deration of boundary effects, The results of this study show that the accu- <br />mlative effect of these five wells would be to lower the water table 2 feet <br />in the first month and by about 7.5 feet after 150 days of pumping. Because <br />the relationship between time and drawdown is exponential the weighted aver- <br />age for the season would be about 5.0 feet. <br />The results of the above observations may be sUlllll&rized as follows: <br />feet-depth <br />9 to 12 <br />1 to 2 <br />.l. to 1.. <br /> <br />Annual static levels <br />Influence of plant use <br />Cuuulative effects of iri'igati.on pumping <br />Water levels in relation to wells <br />where static levels were measured 15 to 19 <br />Adjustment for topography ...:l :L <br />Net level 12 to 16 <br />Area B lies south of Area A along Route SO and the Santa Fe Railroad <br />right of way in Sections 31 and 32, (see Plate I). This area is now being <br />farmed and there are no photos' showing the condition of the area prior to <br />reclamation. It is reported by the Sheltons to have been a marsh area con- <br />sisting of open water and cattails. Our computations have been based on those <br />conditions. <br />The condition described would indicate 811 extremely high water table; <br />prior to reclamation, which has subsequently been lowered by irrigation pump- <br />ing in the area, <br />Area C lies in the east central portion of Section 32, with the River on <br /> <br />-10- <br />