OUR PROJECTS

MPA effectively implemented the use of standard bridge details and components to construct a “standard” bridge with a non-standard pedestrian sidewalk and handrail.

The previous bridge at this location had reached the end of its service life, was hydraulically inadequate and required replacement. MPA completed the bridge planning and geometric design for the new bridge structure and 600 m of gradeline revisions to tie into the new deck height which increased by 3 m over the old structure.

Upon review of the streambed, it appeared that the active degradation had stabilized, allowing a culvert to be a viable replacement option. By providing an SPCSP culvert as a replacement option opposed to a three span bridge, resulted in considerable cost savings to be achieved.

MPA provided a design that allowed for the existing bridge structure to be replaced with a culvert. The implementation of an SPCSP structure resulted in significant cost savings for Clearwater County while maintaining a level of service similar to that of a replacement bridge.

Securing required environmental permits was quite difficult. MPA negotiated extensively on behalf of the Client to ensure a reasonable product was delivered. Bridge alignment and construction issues arose on account of sharp skew angle.

The original structure at this site was greatly undersized which resulted in numerous wash outs and overtopping of the roadway. Additionally, a large amount of drift commonly accumulates at this site. MPA’s design allow for the two pipe structure to be consolidated into a single barrel culvert replacement that adequately passes the design flow.

Custom concrete headwalls were designed to avoid the need for land purchase and fish habitat compensation measures. The new culvert was constructed completely within the existing right-of-way.

MPA effectively implemented the use of standard bridge components to span the large channel width while avoiding the increased costs associated with constructing a major bridge structure at this site.

The elliptical SPCSP structure is nearing the end of its service life and requires ongoing repairs. For this project MPA reviewed the net present value costs of repairing the entire culvert, repairing the critical sections and replacing the culvert.

MPA prepared a design that maintained flow through the existing culvert by installing a culvert liner and increased the overall hydraulic capacity of the crossing by installing two additional welded steel pipes using the trenchless methods.

MPA recommended repairing the culvert by adding struts to extend the life of the structure. The Contractor was requested by MPA to clean the culvert prior to installing the struts in order to provide a uniform bearing along the floor and crown of the culvert.

MPA tailored the standard bridge design to incorporate a sidewalk and a pedestrian handrail on a structure that would otherwise not accommodate pedestrian traffic. Modifying the standard bridge components to provide pedestrian access resulted in cost savings by avoiding the use of a non-standard bridge layout.