Аннотация:Water-level measurements in wells were started by the USGS in Iowa in 1935. Since then a total of about 450 different wells have been measured. The present network consists of about 70 wells. The measurement of these water levels aids in evaluating the present and future water resources of the State. Many factors influence water-level fluctuations. These factors include atmospheric pressure, withdrawals by pumping, earthquakes, earth tides, change in surface loading, discharge to streams, evapotranspiration, and precipitation. Fluctuations produced by artificial discharge through pumping is a common phenomena but unlike the other factors can be regulated and controlled. All present and past USGS observation wells for the State of Iowa since 1935 are listed and located on maps. It is recommended that improvement of the observation-well network by the addition of wells in specific areas should be undertaken as soon as possible.
