Cal. Gov. Code § 23109
The boundaries of El Dorado County are as follows:
Beginning at the junction of the north and south forks of the American River, which is the extreme west corner; thence up the north fork of the American River to the point of confluence of the middle fork of the American River; thence up the middle fork of the American River to the point of confluence of the south fork of middle fork of the American River at Junction Bar; thence up said last-named fork, known as the Rubicon River, to a point where said river is intersected by the section line between Secs. 29 and 32, T. 14 N., R. 14 E., M. D. B. & M.; thence east on the section line through T. 14. N., R. 14 and 15 E. to the northeast corner of Sec. 35, T. 14 N., R. 15 E.; thence north on the range line to the southwest corner of Sec. 30, T. 14 N., R. 16 E.; thence east on the section line to the southeast corner of Sec. 30, T. 14 N., R. 16 E.; thence north to the one-quarter section corner between Secs. 29 and 30, T. 14 N., R. 16 E.; thence through the centers of Secs. 29, 28 and 27, to the one-quarter section corner between Secs. 26 and 27, T. 14 N., R. 16 E.; thence north on the section line to the northwest corner of Sec. 26; thence east on the section line to the northeast corner of Sec. 26; thence north on the section line to the one-quarter section corner between Secs. 23 and 24; thence east through the center of Sec. 24 to the one-quarter corner between Secs. 19 and 24, T. 14 N., R. 16 E. and T. 14 N., R. 17 E.; thence north on the range line to the one-quarter section corner between Secs. 13 and 18;
Thence east to the legal center of Sec. 18, T. 14 N., R. 17 E.; thence north to the one-quarter section corner between Secs. 7 and 18, said township and range; thence east on the section line to the western shore line of Lake Tahoe; thence east in said lake to the state line; thence south and southeasterly on the state line to the northern corner of Alpine, being a point where the state line crosses the eastern summit line of the Sierra Nevada Mountains; thence southwesterly along the west line of Alpine to the common corner of Alpine, Amador, and El Dorado; thence westerly on the northern line of Amador and down the Cosumnes River and south fork thereof, to the eastern line of Sacramento; thence northerly by the eastern line of Sacramento to the south fork of the American River; thence down the latter to the place of beginning.
Ca. Gov. Code § 23109