Lake Buchanan - A Fishing and Boating Mecca in the Central Texas Hill Country Lake Buchanan is 30 miles long and 5 miles wide at the widest point and was the first of the Highland laeks dams created.  It is so big, that it is almost like looking at an ocean in some of the wider parts of the lake.   The 2-mile long dam was built in 1938 primarly to store water and supply hydroelectric power to the area and Lake Buchanan was born!   It managed by the Lower Colorado River Authority (LCRA) which was created in 1934 as a conservation and reclamation district, supplying water and electricity to neighboring areas.  LCRA manages the entire Highland Lakes chain of lakes which start at Lake Buchanan and culminate in Lady Bird Johnson Lake in Austin, TX.   Elevation when full: 1,020 feet above mea... 08/29/2013