Laserfiche WebLink
<br />il <br /> <br /><:::> <br /> <br />L'- <br /> <br />f'- <br />C'J <br /> <br /> -.. <br /> TABLE S.l <br /> Confined Aquifer Water Development Cost Summary <br /> ASSUMED UNIT COST AT UNIT CDST AT <br />HYDROSTRAT- TRANSMISS- AVERAGE WELL 4 MONTHS/YR 12 MONTHS/YR <br />IGRAPHICAL IVITY DEPTH RANGE DEMAND TIME DEMAND TIME <br />UNIT (gpd/ft) (ft) ($faf) ($/af) <br />---------- ---------- ------------ ------------ ------------ <br />HSU-2 250,000 1000-2500 80 50 <br />HSU-3 25,000 2500-4000 318 172 <br />HSU-3 10,000 2500-4000 370 210 <br /> <br />':'> <br /> <br />.....~.i <br /> <br />NOTE: This cost summary assumes the following conditions: <br />1. water development is for in-valley use <br />2. Storativity = 0.0001 <br />3. interest rate = 7 percent per annum <br />4. well spacing = 5 miles <br />5. annual withdrawal = 100,000 af/y <br />3000 feet), and possibly for the deep confined aquifer beneath most of the <br />Valley. <br /> <br />Analysis of pumping effects over a 52-year period (1933-1985) on the <br />elevation of the ground surface in the Valley, and analysis of the physical <br />strength of the confined-aquifer material have led to the conclusion that <br />significant ground water withdrawals from the confined aquifer system will <br />cause a measurable, though probably not severe, degree of land subsidence. An <br />annual withdrawal of 100,000 af/yr from the deep confined aquifer would result <br />in an estimated 0.25 to 0.5 inches per year subsidence in land-surface <br />elevation. <br /> <br />Ground water in the deep confined aquifer, below a depth of about 2500 to <br /> <br />S-4 <br />