Low streamflow events may become more frequent and deliver lower water volumes

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Daily low flows are projected to become more frequent with projected annual increases of 0-13% by end of century (under a low RCP 4.5 and high emissions scenario RCP 8.5) as compared to a historical baseline (1951-2005) (Demaria et al, 2016). Altered winter precipitation that results in in less snow, earlier snowmelt and more variable seasonal precipitation may change soil water storage and groundwater recharge rates. Base streamflow conditions may be reduced as growing seasons become longer and warmer temperatures enhance evaporation rates and plant transpiration. Increases in water demand and usage to maintain public utility water supplies and agricultural requirements may also contribute to reductions in base streamflows (Hayhoe 2007, Demaria et al 2016). Drier climatic conditions that alter the water balance and reduce baseflows may have the greatest hydrologic impact on sensitive systems such as headwater, ephemeral, and other small (low-order) perennial or intermittent systems.