The East Fork Trinity Watershed (HUC 12030106) covers approximately 1,350 square miles in north-central Texas. The watershed is characterized by rolling hills and a mix of rural and urban areas, with much of the land used for agriculture and grazing. The hydrology of the watershed is influenced by the Trinity River, which flows through the eastern part of the area. The surface water in the watershed is used for drinking water, irrigation, and recreation. There are several reservoirs in the watershed, including Lake Lavon and Lake Ray Hubbard, which are used for water supply and recreation. Snowfall is minimal in the area, with an average of only 0.4 inches per year. The climate is characterized by hot summers and mild winters, with an average annual precipitation of 36 inches. There has been a trend of increased precipitation in recent years, which has led to an increase in reservoir levels.