Local road bridges

Overview

In general, bridges on public roads that are not on the provincial highway network or within a city boundary are considered a local road bridge. Direction, control and management of most local road bridges is the responsibility of the local municipal government.

The Local Road Bridge Program provides funding assistance to municipalities for construction, rehabilitation and maintenance of bridge structures on local roads. Funding guidelines under this program are detailed in the GAP-01 document.

The following documents provide design guidance for local road bridge structures:

• Local Road Bridge Design Guidelines (May 2014) – Design guidelines for local road bridges. This document supersedes the GAP-03 document referenced in the GAP-01 document.
• Culvert Design Sheet (April 2007) – A form that can be used instead of site specific design drawings for bridge size CSP and SPCSP culverts.

Local Road Standard Bridge Drawings

Local Road Standard Bridge Drawings can be used on local roads that are not part of the provincial roadway network.

In consultation with the Rural Municipalities of Alberta, we have developed standard bridge designs that can be used on local roads that are not part of the provincial highway system.

Application of these local road standard bridge designs must be limited to sites with conditions that satisfy the design requirements and assumptions of the standard design and the Local Road Bridge Design Guidelines.

Superstructures

Two separate local road standard bridge superstructure designs are available depending on bridge length requirements:

• For bridge lengths of 12m or less, a superstructure consisting of our standard SL precast concrete girders is expected to provide an economical solution.
• For longer bridge length demands, a steel girder superstructure using precast concrete deck panels is expected to provide an economical solution.

Standard local road bridge designs for 18.684m and 24.400m long single span bridges have been developed using this superstructure type.

Both the SL and steel girder superstructure alternatives include single- and 2-lane configurations.

Refer to the Local Road Bridge Design Guidelines for guidance for use of single-lane bridges.

Foundations

An engineered foundation using driven steel piles is included in the local road standard bridge designs for the above noted single span superstructure lengths.

Non-engineered details for a geotextile reinforced soil (GRS) foundation option have also been provided. However, the use of the GRS foundation system requires a site-specific engineered design and the user must be fully aware of the risks associated with the use of this type of shallow foundation.

It is recommended that a risk assessment along with a cost-benefit analysis be performed before pursuing a GRS foundation option.

• Standard drawing for low volume standard bridge single lane SL precast girders on steel substructures
• Standard drawings for low volume standard bridge two lane SL precast girders on steel, precast concrete, or cast in place concrete substructures
• Standard drawings for low volume standard bridge precast concrete panels on steel girders on steel substructure
• Low volume bridge Geosynthetic Reinforced Soil (GRS) foundation typical details  (engineered design required)