Heavy rain showers occur occasionally in the desert, filling arroyos and river beds with abundant and vigorously flowing water. Capturing more of this flow could augment our supplies, whether used directly or recharged. With Tucson riverbeds seeming to offer promising sites, Tucson water history during the twentieth century includes various references to plans for capturing runoff. At times, suitable locations to capture and control mountain runoff have been proposed. Tucsonans looked to the dams along the Salt River as models, but the Santa Cruz River and its tributaries offered no comparable sites suitable for large storage dams.
Studies are underway to determine whether other methods such as inflatable dams can be effective.
In the 1960s and 1970s, removing vegetation along watersheds was considered a promising way to increase water supplies for cities. This strategy was based on the fact that vegetation uses water that otherwise could be put to human uses. Ponderosa and mixed conifer forests were harvested. While initial results often showed an increase in streamflow, long-terms results were not conclusive. Grasses often took over areas denuded of trees, using about as much water as did the trees.