Partial reconstruction of Herbert Street from Allen St. E to George St.

Please be advised that the City of Waterloo has expanded the scope of the Herbert Street reconstruction project to include the section of Herbert Street between Allen Street East and George Street. The purpose of the expanded scope is to replace and upsize the storm sewer between Allen St. E and George St. This work is required to properly increase storm sewer conveyance capacity to current standards and avoid the loss of a significant number (if not all) trees adjacent to the sidewalk on the west side of Herbert from Union to Allen.

The reconstruction between Allen St. E and George St. involves the replacement and upsizing of the storm sewer running under the western portion of the street, service laterals (as necessary) to facilitate the storm sewer replacement, as well as replacement of surface works. This will likely result in new sidewalk, driveway aprons and curb & gutter along the west side of the street, as well as new asphalt pavement structure on much, if not all, of the roadway.

Over the coming days and weeks, the City will complete a topographic survey, geotechnical investigation and Closed Circuit Television (“CCTV”) inspection of the sewers. The topographic survey team will need access to your property but should not interfere with your regular activities. The surveyors will identify themselves if you have any questions. The drilling crew that will perform the geotechnical investigation to assess soil and groundwater conditions will not need access to private property and will work entirely within the public right-of-way. The CCTV inspection crew may occupy lanes of the road but are not expected to close the road entirely.

The City understands that residents, especially between Allen St. E and George St., will likely have many questions about the rationale for this additional work and disruption, so additional details are provided below:

Why is the reconstruction of Herbert Street extending to George Street?

During preliminary design for the reconstruction of Herbert Street between Union St. E and Allen St. E, the City’s engineering consultant noted several challenges with the design for the storm sewer. These challenges stem from the need to increase the diameter of the storm sewer to meet current design standards, and the already shallow depths of all utilities on the street.

Increasing the diameter of the sewer (keeping the same bottom elevation) would put the top of sewer far shallower than standards permit which cause constructability issues. Lowering the storm sewer will put it in conflict with the sanitary service laterals to the homes on the west side of Herbert Street. Another alternative is to install a second sanitary sewer under the sidewalk on the west side of Herbert Street to service the homes on the west side of the street, however the proximity of the sewer to existing trees would likely require the removal of most, if not all, trees on the west side of Herbert.

Why wasn’t this work completed in 2019 when the Region installed the new raw watermain?

The reconstruction of Herbert Street was not within the City’s 10-year planning horizon for reconstruction when the Region installed the new raw watermain. The reconstruction of Herbert was advanced in the queue following discovery of numerous lead water service laterals to homes on Herbert Street between Allen St. E and John St.

Why do a full road reconstruction now? Why not just replace the lead water services?

Although Herbert Street was not within the City’s 10-year plan for reconstruction, it needs a full reconstruction according to the City’s asset management system.

Other benefits of replacing the storm sewer between George and Allen:

The storm sewer on Herbert, north of Allen, is undersized and in poor condition. The sewer is at a critical point, acting as a trunk in the sewer system for the area. Lowering and upsizing the sewer now will make future reconstructions elsewhere in the neighbourhood easier by providing greater potential depth for upsizing sewers further upstream in the system. The section of Herbert St. between George St. and Allen St. E has also had the sanitary sewer (1998) and watermain (2019) replaced. Replacing the storm sewer now completes the replacement of underground utilities for that section of street.