045-12 Wyo. Code R. § 12-4
(a) Connections to Department storm sewer systems shall only be allowed if the system has the capacity to handle the additional inflow. Construction of the connection and restoration of pavement and right-of-way shall be as directed by the engineer.
(b) Major trunk lines and outfall lines, not connected with highway drainage, shall not be allowed parallel encroachment in narrow highway rights-of-way, especially if roadway reconstruction, widening or slope modification is contemplated in the foreseeable future.
(c) When parallel encroachment is allowed the line shall be located as close to the R/W line as possible.
(d) Crossings of the roadway and/or paved side streets and approaches may be made by either boring a casing pipe or heavy wall thickness carrier pipe under the roadway template. Crossings of the roadway template shall be as near to perpendicular to the roadway centerline as possible.
NOTE: The requirement for casing of the road crossing shall be specifically discussed between the applicant's engineer and the Department's engineer and shall among other things depend on the pipeline materials used and the system's operating pressure.
(e) Depth of cover shall be a minimum of four (4) feet below natural ground or roadway ditch flow line.
(f) Shallow depth of cover with a protective dirt berm over the top shall not be allowed.
(g) When parallel encroachment within the roadway template and/or the pavement section is unavoidable, the pipe and manholes used shall be able to withstand highway loading, as determined by manufacturers data, and be of the most durable and maintenance free material.
(h) All manholes shall be constructed flush with the surrounding terrain and if in the paved portion of the roadway in a manner that allows for adjustment for future changes in pavement thickness.
045-12 Wyo. Code R. § 12-4