ORS § 366.465
The Department of Transportation may erect and maintain gates and stock or cattle guards in state highways at such points where the highways are crossed by drift or stock fences, where such highways intersect state or government-owned highways or other public highways and at other places in the state highways as the department may deem for the best interests of the public. The department may issue permits for the erection and maintenance of the same. Any gates constructed under this section must be constructed and maintained upon the right of way and not upon the traveled portion of the highway. If gates or stock guards are constructed under this section pursuant to a permit issued by the department, then the permit may contain such conditions, obligations and requirements as the department may deem for the best interests of the general public.
ORS 366.465