Utah Code Ann. § 63G-7-301
(1)
(2) Immunity from suit of each governmental entity is waived:
(3)
(a) Except as provided in Subsection (3)(b), immunity from suit of each governmental entity is waived as to any injury caused by:
(b) Immunity from suit of each governmental entity is not waived if the injury arises out of, in connection with, or results from:
(5) Immunity from suit of each governmental entity is not waived under Subsections (3) and (4) if the injury arises out of, in connection with, or results from:
(n) the operation or existence of a pedestrian or equestrian trail that is along a ditch, canal, stream, or river, regardless of ownership or operation of the ditch, canal, stream, or river, if:
(iii) the written agreement:
(s) the activities of: