Ephemeral-Stream Channel and Basin-Floor Infiltration and Recharge in the Sierra Vista Subwatershed of the Upper San Pedro Basin, Southeastern Arizona

摘要

The timing and location of streamflow in the San Pedro River are partially dependent on the aerial distribution of recharge in the Sierra Vista subwatershed. Previous investigators have assumed that recharge in the subwatershed occurs only along the mountain fronts by way of stream channel infiltration near the contact between the low permeability rocks of the mountains and the basin fill. Recent studies in other alluvial basins of the Southwestern United States, however, have shown that significant recharge can occur through the sediments of ephemeral-stream channels at locations several kilometers distant from the mountains. The purpose of this study was to characterize the spatial distribution of infiltration and subsequent recharge through the ephemeral-stream channels in the Sierra Vista subwatershed.