Diagnostic Hydrologya

Abstract

ABSTRACTThis paper examines two eases of surface‐water/ ground‐water interrelationships, one in Beaufort County, North Carolina and one in Ramona, California. In each case the author has to make a differential diagnosis between alternate solutions rendered by hydrologic methods.In the first ease, the author proves that the pumping and subsequent wastage to the ocean of 65 mgd in order to operate the Texas Gulf Sulphur phosphate mine, in all likelihood poses no threat to the environment.In the second case, the author has attempted to obtain, by means of the theory of ground‐water flow, an estimate of the physiographic volume of the Santa Maria creek ground‐water basin in Ramona. He has submitted the outcome of his calculations to the test of compatibility with the results of an actual pumping test, and with pumping records made available by the Ramona Municipal Water District. The outcome shows a water storage capacity of the order of 4,600 AF for the entire basin.In order to correlate recharge of the basin directly with the precipitation on the basin, a hydrograph analysis has been done for the 20 largest runoff‐producing months of the streamflow records 1965–1982. From this study it follows that the average (annual) recharge to the basin is of the order of 1,340 AF/yr and that the physiographic volume, as derived previously, is amply adequate to absorb this recharge.