The South Fork of the San Gabriel forms four miles east of Burnet in Burnet County running 34 miles eastward through Williamson County before it joins the North Fork in Georgetown. The North Fork forms 12 miles north of Burnet in Burnet County and flows southward for 43 miles into Williamson County to its confluence with the South Fork in Georgetown. The North Fork is impounded about three miles northwest of the confluence of the two forks to form Georgetown Lake. The two forks are very similar. Both are scenic, winding rivers with numerous limestone bluffs. However, recreational use is restricted to periods of sufficient rainfall since they tend to not maintain consistent water flow.