Reliable tools are needed by farmers and managers to estimate and mitigate impacts of altered hydrology and degraded water quality downstream of agricultural areas. The Water, Energy, and Biogeochemical Model (WEBMOD) (Webb and Parkhurst 2017) was used to simulate daily variations of hydrology and water quality for 5 square kilometers of irrigated fields draining to the DR2 Drain, southeast of Yakima, WA.