[4] East Yegua Creek forms about nine miles southwest of Rockdale, Texas in southern Milam County as a drainage in farm and ranch territory.

The East Yegua is intermittent and very shallow in its upper reaches, commonly flowing with significant volume only after rainfall.

The East Yegua runs through generally flat terrain with shallow depressions, clay and sandy loam soils which support water-tolerant hardwood trees, conifers and grasses.

[5] Alcoa Lake is the result of the impoundment of Sandy Creek, seven miles southwest of Rockdale in Milam County.

Alcoa Lake is owned and operated by the Aluminum Company of America for industrial purposes at the site, and in recent years for recreational use.