"Katharine Coman's "Some Unsettled Problems of Irrigation," published in March 1911 in the first issue of the American … and irrigation districts that emerged in the American West in the late 19th and early 20th centuries in response to …

, technological improvements made groundwater from the Ogallala aquifer available for irrigation. Comparing counties over the Ogallala … with nearby similar counties, groundwater access increased irrigation intensity and initially reduced the impact of …