Idaho Code § 31-141
Power county is described as follows: beginning at the northwest corner of section thirty-one (31), township six (6) south, range thirty (30) east; thence east along the section line between sections thirty-one (31) and thirty (30), township and range aforesaid, and an extension thereof to the point where such extended line intersects with the center of the west channel of Snake river; running thence up the center of the west channel of Snake river, upon and along the boundary line of Bingham county, to the point in the main channel of said river, where the same divides, forming the east and west branches thereof; thence southerly down the center of the east branch of Snake river to the point of intersection of the center line of said east branch with an extension of the center line of the Portneuf river in section seventeen (17), township six (6) south, range thirty-two (32) east; thence up the Portneuf river, to the intersection of the Portneuf river with the west boundary line of section eight (8), township six (6) south, range thirty-four (34) east, Boise meridian; thence south four and one-quarter (4 1/4) miles to the southeast corner of section thirty-one (31), township six (6) south, range thirty-four (34) east, Boise meridian; thence west to the northeast corner of section six (6), township seven (7) south, range thirty-four (34) east, Boise meridian; thence south four (4) miles to the southeast corner of section nineteen (19); thence east one (1) mile to the northeast corner of section twenty-nine (29); thence south four (4) miles to the southeast corner of section eight (8), township eight (8) south, range thirty-four (34) east, Boise meridian; thence east two (2) miles to the northeast corner of section fifteen (15); thence south two and one-half (2 1/2) miles to the east quarter (E1/4) corner of section twenty-seven (27); thence east one (1) mile to the east quarter (E1/4) corner of section twenty-six (26); thence south one and one-half (1 1/2) miles to the southeast corner of section thirty-five (35), township eight (8) south, range thirty-four (34) east, Boise meridian; thence east one (1) mile to the northeast corner of section one (1), township nine (9) south, range thirty-four (34) east, Boise meridian; thence south two (2) miles to the southeast corner of section twelve (12); thence east two (2) miles to the northeast corner of section seventeen (17), township nine (9) south, range thirty-five (35) east, Boise meridian; thence south one and one-half (1 1/2) miles to the east quarter (E1/4) corner of section twenty (20); thence west one-half (1/2) mile to the center of section twenty (20); thence south two and one-half (2 1/2) miles to the south quarter (S1/4) corner of section thirty-two (32), township nine (9) south, range thirty-five (35) east, Boise meridian; thence east to the northeast corner of section five (5), township ten (10) south, range thirty-five (35) east, Boise meridian; thence south one and one-quarter (1 1/4) miles to the southeast corner of the northeast quarter (NE1/4) of the northeast quarter (NE1/4) of section eight (8); thence west one-quarter (1/4) mile; thence south one-quarter (1/4) mile; thence west one and one-quarter (1 1/4) miles; thence south three-quarters (3/4) of a mile; thence west one-quarter (1/4) mile to the southwest corner of lot one (1) of section eighteen (18), township ten (10) south, range thirty-five (35) east, Boise meridian; thence south on the range line three and three-quarter (3 3/4) miles to the southwest corner of township ten (10) south, range thirty-five (35) east, Boise meridian; thence west along and upon the south line of said township ten (10) (1913, ch. 6, section 2, pp. 31, 32), to a point a distance of two (2) miles east from the southeast corner of township ten (10) south, range thirty-three (33) east; thence south to a point where the line thus drawn intersects the line between townships eleven (11) and twelve (12) south, range thirty-four (34) east; thence west along and upon the line between townships eleven (11) and twelve (12) south (1915, ch. 132, section 2, p. 288), to the southeast corner of township eleven (11) south, range thirty-two (32) east; thence south upon the township line to the southeast corner of township twelve (12) south, range thirty-two (32) east; thence west upon and along the southern line of said township twelve (12), to the southwest corner of township twelve (12) south, range thirty (30) east; thence north upon the range line between ranges twenty-nine (29) and thirty (30) east, to the southwest corner of township nine (9) south, range thirty (30) east; thence west along and upon the south line of township nine (9) south, to the southwest corner of section thirty-four (34), township nine (9) south, range twenty-eight (28) east; thence north upon and along the line between sections thirty-three (33) and thirty-four (34), township nine (9) south, range twenty-eight (28) east, and an extension thereof to the point where said line so extended intersects the center of the main channel of Snake river; thence down the center of the main channel of Snake river to the point of intersection with the range line between ranges twenty-seven (27) and twenty-eight (28) east; thence north along and upon said range line to the northwest corner of township nine (9) south, range twenty-eight (28) east; thence east upon and along the north line of said township nine (9) south, to the northeast corner of section four (4), township nine (9) south, range twenty-eight (28) east; thence in a northerly direction along and upon the section line which, when surveyed, will be between sections thirty-three (33) and thirty-four (34), township eight (8) south, range twenty-eight (28) east, and an extension of such line to the point where such extended line will intersect with the township line which, when surveyed, will be the township line between townships seven (7) and eight (8) south, range twenty-eight (28) east; thence west upon the township line to a point which when surveyed, will be the southwest corner of township seven (7) south, range twenty-eight (28) east; thence north along and upon the range line which, when surveyed, will be the range line between ranges twenty-seven (27) and twenty-eight (28) east, to a point which will be, when surveyed and established, the northwest corner of township four (4) south, range twenty-eight (28) east; thence east along and upon the line which will be, when surveyed, the north line of said township four (4) south, to the northwest corner of township four (4) south, range thirty (30) east; thence south along the range line, the same being the western boundary line of Bingham county, to the northwest corner of section thirty-one (31), township six (6) south, range thirty (30) east, the point of beginning (1913, ch. 6, section 2, pp. 32, 33).
Idaho Code § 31-141