The Llano Watershed (HUC 12090204) covers an area of approximately 8,618 square miles in central Texas. The watershed is characterized by a semi-arid climate with hot summers and mild winters. The hydrology of the watershed is dominated by the Llano River and its tributaries, which provide critical surface water to the region. The watershed also contains several reservoirs, including Lake Buchanan and Lake LBJ, which are important sources of drinking water and recreation for the surrounding communities. The region experiences periodic droughts and floods due to its variable climate. The watershed is also home to several endangered species, including the golden-cheeked warbler and the black-capped vireo. In recent years, the region has experienced a decline in snowpack due to rising temperatures, which has led to concerns about water availability in the future. Overall, the Llano Watershed is an important resource for the region and requires careful management to ensure its sustainability.