Design guidelines for bridge size culverts
The Department considers any structure with an equivalent diameter of 1,500 mm or greater to be a Bridge Size Culvert. The design of Bridge Sized Culverts shall follow the Design Guidelines for Bridge Size Culverts (PDF) and shall be drafted in accordance with the Engineering Drafting Guidelines for Highway and Bridge Projects. Information pertaining to the conceptual design for culvert sites can be located at Bridge Conceptual Design.
For the purpose of culvert design, standard culverts are defined as structures with an equivalent diameter greater than or equal to 1,500 mm and less than 4,500 mm in diameter. For culverts up to 3,000 mm in diameter, the current version of standard drawing S-1418 Installation of Large Metal Pipes (PDF) may be applied. For any pipes larger than 3,000 mm, site specific construction drawings are required.
Major culverts are defined as structures with an equivalent diameter of 4,500 mm or greater; or structures with a lesser diameter having complex site constraints or specialized engineering requirements. Design Data drawings may be required at these sites, particularly if there are changes to the road alignment. Construction drawings are based on the necessary Design Data drawings.
For Bridge Size Culverts located on Local Roads, the Culvert Design Sheet (PDF) may be used in lieu of Design Data drawings, provided the criteria laid out in the Culvert Design Sheet Guideline (April 2007) (PDF) are met.
See Local road bridges for guidance on the design and installation of bridge size culverts.