The City of Guelph has initiated a Class Environmental Assessment study to investigate opportunities for improvements to Niska Road from the Downey Road to the City Limits.
Segments of the roadway and the bridge over the Speed River are nearing the end of their useful life and require a solution to address their deterioration and increasing maintenance costs. In addition to reviewing a variety of road cross-sections, improvements to the Downey Road intersection, impacts to the environment and community road safety issues, a range of bridge solutions were examined including, but not limited to, bridge closure, rehabilitation or replacement.
Why is the City recommending upgrades to Niska Road including the bridge?
The current structural inspection of the Niska Road bridge concluded that a number of bridge elements are nearing the end of their useful life and need rehabilitation within three years. As well, the existing road format does not meet current standards and is nearing the end of its useful life.
The most recent inspection of the Niska Road Bridge was completed in 2013 concluded that,
“Overall the structure is in very poor condition with an aggregate condition index of 22.2 out of 100. The major concerns at this site are the water encroaching against abutments as a result of span opening being shorter than watercourse width (this situation may lead to unstable substructure in case of high volume water – flooding), road constriction, absence of a pedestrian access, absence of traffic barrier, progressive undermining of the northwest retaining wall, severe failure of the northwest embankment, partial failure of northeast embankment, improper signage, severe corrosion of the bearing plates, isolated severe corrosion of the bottom chords at the ends and west end verticals, partial poor condition and progressive deterioration of the bearing seats and progressive deterioration of the masonry retaining walls.”
In other words, the primary concern with the bridge structure is that the span opening (i.e. distance between the abutments) is shorter than the watercourse width which is resulting in ongoing erosion and undermining of the retaining walls and abutments by the river. Although the superstructure itself had structural components replaced in 2003 (transoms, sway bracing, bolts and wood decking), the superstructure is now experiencing significant corrosion and there is a need to replace the steel trusses and bearings. The report recommended rehabilitation take place within one to five years. This represents the highest urgency outside of emergency action.
Is the bridge safe?
The bridge is safe for travel. Repairs done in 2015 will keep the bridge in service while the City completes the Environmental Assessment and determines a permanent solution for Niska Road and bridge.
What options were evaluated through the Environmental Assessment process?
|repair bridge and maintain||$1,300,000*|
|close bridge to vehicular traffic and maintain||$1,000,000*|
|new single lane bridge||$2,000,000|
|new two-lane bridge||$2,500,000|
* These are initial capital costs only and do not include ongoing maintenance costs
What are the cost estimates of the final recommendations?
|Project Components||Estimated amount|
|construction of a two–lane bridge|
|steel girder bridge||$2,072,700|
|pony truss bridge||$2,742,000|
|reconstruction of Niska Road||$2,088,500|
|reconstruction and signalization of Niska–Downey intersection||$450,000|
|estimated total with steel girder bridge (excluding HST)||$4,611,200|
|estimated total with steel girder bridge (excluding HST)||$5,280,500|
Why is the option to repair and maintain the bridge so expensive?
Bailey bridges were never intended for permanent use and current Ministry of Transportation Ontario policy discourages the use of modular bridges for permanent installation. Finding replacement components for Bailey bridges is becoming more difficult. In some instances, panels have to be specifically fabricated to match. Bailey bridges are modular and components can be replaced, however life cycle costs would be higher compared to other bridge types of similar size due to the ongoing maintenance requirements.
In addition to the superstructure, the abutments also require extensive repair and/or stabilization. The work would include re-pointing the existing masonry work, replacing any blocks as may be required, removing and replacing the mass concrete and concrete block system or something similar at all four corners at an estimated cost of approximately $400,000. A repair of this nature would provide an estimated 15 year service life at which point additional costs would incurred for repairs due to ongoing erosion and undermining by the river.
What is the City recommending for the bridge?
Environmental assessments evaluate multiple criteria including socio-economic/cultural, natural, financial and technical factors. The evaluation for the Niska Road study indicates that the best option for the bridge is to replace the existing Bailey bridge with a new, two–lane pony truss bridge. The bridge could be designed to look similar to the exisiting bridge, and the City plans to mitigate viewscape and tree impacts through minimal changes to the road profile, and by minimizing the urban road cross section.
Did the City use input from the Community Working Group?
Yes. The City heard and responded to all input and questions from the Community Working Group.
Is the City recommending something that is not supported by members of the Community Working Group?
The group has not reached consensus. Some members support the preliminary preferred alternative of a two-lane bridge while others do not.
How did the City use input from the community?
Alternatives for any project are evaluated using a detailed and complex set of criteria that include socio-economic/cultural, natural, financial and technical factors. Community input, whether from an individual or a group, is evaluated as part of socio-economic/cultural critera.
After evaluating all of the criteria, the recommended improvements are to reconstruct the road and replace the existing bridge with a new, two–lane bridge. Detailed designs were created to help stakeholders understand more about the proposed changes, including how the City plans to approach traffic calming measures and mitigate potential impacts on the environment and cultural heritage.
Public input collected throughout the consultation period (open houses, surveys, etc.) showed a slight preference for replacing the bridge with a two-lane bridge. Compiled feedback is presented below:
- 47 per cent of respondents supported road reconstruction
- 40 per cent supported a do nothing approach for the road
- 13 per cent were in favour of repaving
- 34 per cent support a new, two–lane bridge
- 25 per cent agreed with a do nothing approach for the bridge (Note: this is not a viable option due to the condition of the bridge but is required to be included as part the EA evaluation process)
- 20 per cent wanted it closed to vehicular traffic
- 18 per cent preferred replacing the existing bridge with a new, one–lane bridge
- three per cent wanted the bridge removed
Why not just close the bridge permanently?
The bridge remains an important local transportation route within our community. Niska Road is designated as a collector road in the City’s Official Plan. The purpose of the EA was to identify a permanent solution for improving Niska Road and the bridge to ensure continued safety for people walking, cycling and driving on Niska Road.
Will a two-lane bridge encourage more traffic and make the situation even more unsafe?
We expect increases on all Guelph roads as our community grows. Niska Road is not being expanded. Modeling of expected increases on Niska Road demonstrate that the two–lane road will continue to safely meet traffic needs. Widening the lanes will simply bring Niska Road up to current road safety standards.
- Niska Road and bridge are part of a stable road system servicing existing neighbourhoods with established travel patterns.
- Traffic modeling completed by the City predict that peak two-way traffic volumes will increase from approximately 510 vehicles per hour (vph) to 700 vph in 2031.
- A two–lane road has sufficient capacity for this volume.
- Traffic calming measures were considered and added into the proposed designs.
Why would the city encourage regional traffic through a stable neighbourhood?
The City is not encouraging any use of the road beyond that which is intended. The City is working to improve the road conditions to meet the need of its intended use, and to meet required safety standards.
The purpose of a collector road is to move low to moderate volumes of traffic within specific areas of the city, and collect local traffic for distribution to the arterial or Provincial highway system.
What other opportunities will the community have to comment?
When the City issues a notice of completion, the Environmental Study Report will be placed on the public record for the mandatory 30–day public review period.