Part 3 – Road Works

3.23    Stock Crossings

3.23.3    Stock Underpass

If a Stock Underpass is required it shall comply with the following:

• The Stock Underpass length shall be a minimum of 7 m either side of the centre of the road.  However the final length of the underpass will depend on traffic volume, seal and shoulder width, in situ soil conditions, depth and angle of underpass, construction of wingwalls, roadside drainage requirements, traffic safety/risk assessment or any other site specific factors.  The developer shall discuss the requirements for the underpass with the Asset Manager - Strategy and Policy before finalising the design.
• The Underpass shall be designed in accordance with the NZ Transport Agency Bridge Manual (September 2004) to HN-HO-72 loading.
• The minimum cover for the underpass shall be as per manufacturing specifications.
• The Underpass shall allow for drainage of the underpass floor and surrounding ground.
• Retaining/wing walls shall be designed to retain the embankment fill.
• Any cut slopes shall be laid back to a safe slope or retained with a properly designed retaining wall.
• A producer statement from the designer of the proposed underpass structure shall be submitted.
• Barrier rails to warn approaching traffic of the hazard shall be installed.  The ends may require bridge end or hazard markers as determined by Council’s Roading Engineer. A white painted post and rail fence (minimum two coats white acrylic paint) shall be erected from the property boundary fence around the top of the batter of the underpass and back to the boundary fence.  The fence shall consist of a minimum of three rails made with timber posts with a diameter of 150 mm and rails of 150 mm by 50 mm.
• The ends of the underpass shall be sufficiently retained to prevent the loss of fill material and stormwater into the underpass openings.
• The pavement shall be reinstated to the same line and levels that existed prior to the construction of the underpass.  The pavement material shall comply with Section 3.5 – Road Pavement.
• The applicant shall be responsible for locating and managing all services within the road reserve in vicinity of the works.
• A suitably qualified Engineer shall sign off the design, construction works and the finished Stock Underpass. (Note:  It is recommended that you discuss with Council prior to work being undertaken to determine who is considered suitable for a particular situation.)
• A suitably qualified Contractor who shall construct the Stock Underpass, having the relevant health and safety procedures and having undertaken similar works in the past.