Current through Register Vol. 43, No. 39, September 26, 2024
(a) At least two
permanent benchmarks shall be installed for future reference at each dam. Each
benchmark shall be located according to the following criteria:
(1) In an area where the benchmark will not
be disturbed, destroyed, or inundated after the dam is complete; and
(2) along the centerline of the dam on either
end of the dam, if practical, and in undisturbed soil.
(b) On high-impact dams, each permanent
benchmark shall also meet the following criteria:
(1) Be installed in a hole that meets the
following criteria:
(A) Is 12 inches in
diameter; and
(B) is at least 42
inches deep or is drilled to bedrock, whichever is less;
(2) be constructed of one or more steel
reinforcing bars at least 38 inch in diameter and 36 inches in length or the
length of the depth of the hole, whichever is less. The reinforcing bar or bars
shall be placed in the hole and the hole backfilled with concrete rounded off
flush with the ground;
(3) be
capped by a metal survey marker; and
(4) be either marked by a witness post or
survey marker sign or tied to at least two objects in the vicinity by distance
and bearing.
(c) On
low-impact dams, each permanent benchmark shall also meet the following minimum
requirements:
(1) Be constructed of a
reinforcing bar that is 36 inches long, one-half inch in diameter, and driven
flush with the surface of the ground;
(2) be installed at a location protected from
grazing animals and vehicular traffic; and
(3) be either marked by a witness post or
survey marker sign or tied to at least two objects in the vicinity by distance
and bearing.
(d)
(1) The elevation and horizontal location of
each permanent benchmark shall be shown on the as-built drawings or the
construction inspection report. The location of each permanent benchmark shall
be described in reference to centerline stationing and offset from the
centerline. The elevation of each permanent benchmark for all of the following
classes of dams shall be referenced to the national geodetic vertical datum of
1988, or other acceptable national vertical datum, to a tolerance of plus or
minus 0.5 foot:
(A) Class size two, hazard
classes B and C;
(B) class size
three dams; and
(C) class size
four dams.
(2) The
elevation of each benchmark for class sizes one and two, hazard class A dams
may be referenced to an assumed datum.
(e) Horizontal control shall be referenced to
the Kansas state plane coordinate system as set forth in
K.S.A.
58-20a01 et seq., and amendments thereto. The
location of each benchmark shall be shown on the as-built drawings or the
notice of completion by using either of the following:
(1) The plane coordinate values consisting of
a northing and an easting from the appropriate monumented point according to
K.S.A.
58-20a03, and amendments thereto; or
(2) the feet distances north or
south, and east or west, from the nearest or most convenient section corner.
