Keats Way: Tributary Channel to Clair Creek restoration & storm sewer bypass

Thank you to everyone who was able to attend our neighbourhood meeting on December 1. If you were unable to attend or are looking for follow-up information, we have added some additional files to this project page. A reminder that the City lead for this project is now Gavin Vermeer, and he is the main point of contact moving forward. Additional project information now available includes:

• the meeting presentation is available for anyone unable to attend
• a frequently asked questions section with questions from the meeting
• the technical drawings, including floodplain and tree removals, are available in the Document Library section

The technical drawings include:

• Keats Way Creek Restoration Erosion and Sediment Control – C-205 Identifies limits of creek work, blue line showing legal easement boundaries, predicted areas to be disturbed as well as construction access plans.
• Keats Way Creek Restoration Proposed – C-206 Identifies the new creek design including areas where soft armouring will be installed and areas where hard armour stone will be installed.
• Keats Way Creek Restoration Removals – C-203 Identifies removals such as pedestrian bridges and eave troughs entering the easement. Trees required to be removed are NOT identified in this drawing.
• Keats Way Creek Restoration Removals – C-204 Identifies trees identified as may needing to be removed. Each tree identified for removal is numbered and listed in the tree removal chart.
• Keats Way Creek Flood Plain Figures Two drawings that show the existing flooding conditions and the proposed conditions after the bypass and the creek restoration have been completed. The flooding conditions are modelled for a 1 in 5 years storm event, which has a 20% chance of happening in any particular year.
• Keats Way Storm Bypass Existing Conditions and Removals-C-100 Identifies the limits of the new storm sewer bypass work, including the area of disturbance, which side of the road will be under construction.
• Keats Way Storm Bypass Proposed Conditions Opt A –C-200 Identifies the details of the proposed design for the bypass for the west side of the project limits.
• Keats Way Storm Bypass Proposed Conditions Opt A – C-201 Identifies the details of the proposed design for the bypass for the east side of the project limits.
• Keats Way Storm Bypass Tree Protection and Removals – C-204 Identifies the trees identified as needing to be removed for the new storm sewer bypass construction.

If you are unable to access any of these files and require this information in another format, please let Gavin know.

We understand that not all residents will be able to attend the neighbourhood meeting. The information is presented here for your information, and we encourage you to connect with our project team directly if you require this information in an alternate format, or if you have questions. The presentation boards are also available.

Date: December 1, 2022
Time: 6:30 p.m. – 8:30 p.m.
Location: Keatsway Public School: 323 Keats Way, Waterloo, ON N2L 5V9

This project involves the restoration of a portion of Clair Creek between Keats Way and McDougall Road to reduce the risk of erosion, flooding and damage to private property in the area. Recommended works include replacing retaining walls supporting the creek bank, and installing a new storm bypass along Keats Way to reduce flooding risks.

Project priorities

• Protect existing building structures
• Reduce risk to public safety
• Reduce risk of flooding to the adjacent properties

In the fall of 2021, the City reached out to the neighbourhood to gather information about property owner’s experiences. A number of properties had experienced flooding from Clair Creek, while some properties experienced no flooding at all. This information was used to help determine the need and the scope of the project and to help focus efforts on areas that were experiencing the worst flooding.

Existing site conditions and current flood mapping

The section of Clair Creek from Keats Way to McDougall Road is defined as “a confined channel with gabion basket bank treatments”. The existing municipal storm sewer on Keats Way, west of Keats Walk, discharges to a tributary via a culvert and flows around the existing residential properties on Keats Way Place. The tributary ultimately meets with Clair Creek, west of McDougall Avenue.

Generally, the creek channel consists of gabion baskets along the majority of the banks of the creek, with grassed areas and trees on either side of the overbanks. The gabion baskets are failing in multiple locations along the creek corridor, within 5 metres of buildings on private property in certain areas.

Our project team has completed a great deal of preliminary work to help come up with the best options for the creek restoration. That work included an assessment of plants and animals in the area (no species-at-risk or species-of-conservation-concern plants or animals were identified, and 577 trees were recorded), and looking at how the creek flow changes. The ground and subsurface were assessed, and buried utilities were located. Flood modelling and mapping was also done.

This area is currently recognized by Grand River Conservation Authority (GRCA) as floodplain. The floodplain is based on regional storm events (Hurricane Hazel). Flood modelling and mapping helps us identify areas that may be at risk of flooding during severe storms. Residential properties in the area are regulated by the GRCA. This means that any construction work or development activities on these properties will need a GRCA permit, in addition to a building permit or other approvals from the City and other agencies.

As part of the flood modelling, we determined that a creek bypass would be needed to prevent flooding on residential properties during a 5-year and 25-year storm event.

Given the information gathered by the project team, we then looked at alternatives for restoration using the following considerations:

• Access to the area through properties for construction, and how much the alternative will cost to construct and maintain.
• Minimizing impacts to buildings and roads.
• No increase to flooding or erosion.
• Maintaining existing infrastructure, such as pedestrian crossings over the creek and the two storm sewers from Keats Way and Keats Way Place that empty to the creek
• Natural channel design, with appropriate landscaping to stabilize the creek banks
• Consideration for natural habitats and fish passage through the corridor.

Creek stabilization

The preferred method for creek restoration will involve the use of soft armoured walls and living walls where appropriate, as well as hard armoured walls.

Soft armouring techniques such as a “living wall” can be used to reinforce the slope and provide erosion protection in areas where there is sufficient space and less risk to public safety or flooding. In some parts of the study area, tree cover over portions of the creek might make it difficult to grow vegetation on the slope. In those areas we would use appropriate grass seed mix and plants that thrive in partial sun or shaded areas.

Using soft-armouring in areas where the existing retaining wall is within 5 metres of a residential structure would be difficult. Therefore, in those areas hard-armouring would be used.

A typical armoured stone retaining wall consists of a combination of hard and soft armourstone. It includes a hard armoured wall, which consists of large, rectangular blocks of stone that are placed on top of each other forming a wall along the streambank. The large rectangular stone blocks make up the main structural component, with the stone’s size and weight it can help to prevent damage from flowing water.

Property owners can contact the project team directly to discuss which technique will be used on their property.

Creek bypass

Four options were developed and reviewed for the proposed bypass:

• Option #1: Do nothing for bypass, and only restore the creek
• Option #2a: Discharge to existing McDougall Road Culvert
• Option #2b: Discharge directly to Clair Creek
• Option #3: Underground storage with controlled discharge

Doing nothing is not recommended, since restoring the creek will not address flooding concerns during large storm events. The three other options all provide considerably better flood control during a major storm event, with option 2a being preferred as the most cost-effective, and least invasive for construction.

Construction timeline and information

• Winter 2023: start creek restoration
• Spring 2023: bypass construction (continues through Summer 2023)
• Summer 2023: continue and finish creek restoration

Construction work will involve:

• Installation of cofferdams
• Temporary lane closures on Keats Way
• Removals (of existing gabion baskets, landscaping, etc.)
• Installation of the preferred solution

Additional removals will include some trees, landscaped areas and some creek crossings. A Tree Protection Plan will be in place for those trees remaining in the project area, and landowners will be notified to remove any plantings or gardens that they want to retain before construction begins. The project team will work with landowners to restore impacted areas. Several existing creek crossing structures will also need to be removed for the work to be done. Discussion will be held with landowners to wish to maintain a creek crossing so that no damage will be done to the restoration work.

Our goal is to maintain work within easement as much as possible. If workers are required to work outside the easement, homeowners will be contacted.

Construction along Keats Way will include lane closures along portions of the street (along the school) and traffic control between Keats Walk and McDougall Road would be used as needed to ensure safe passage for pedestrians and cyclists, and maintain two-way one-lane traffic through the work area. The work would not impede access to Keats Walk, Karen Walk, and Keats Way Place. Bus stops will also be relocated. Traffic control plans will be finalized before the start of construction and landowners will be notified.

Immediate next steps for this project involve completing the detailed design of the work, including construction drawings and specifications, tendering of the construction work and approval of the tender, followed by construction.

If you have any questions, our project team will be happy to address them.

Thank you to everyone who took the time to complete the survey regarding Clair Creek and the nearby properties. This information will be very helpful to the project team as we move forward. The City of Waterloo is now working with AECOM as the consultant on this project. AECOM will be responsible for the project site investigations, engineering analysis and detailed design work. More information on these stages, as well as a project contact from AECOM will be provided once available. In the meantime, if you have any questions, you can continue to reach out to our city project contacts.

During the course of this project, city staff and our consultants and contractors may need to enter onto private property to conduct a number of tasks related to the design and construction of the creek restoration. Access will always be through properties that currently contain an easement, and properties with an easement have been contacted via mail.

The background work for this project was part of the city's Stormwater Management (SWM) Master Plan study. Public consultation for the study happened throughout 2017 and 2018, and the plan was completed in 2020. The plan is a very large document, and has been split into several sections on the city's website to help make it more accessible.

The part of the SWM Master Plan that relates to this project can be found on page 215:

12.4.2.7 Clair Creek Tributary 1, Site CLR-T1-E1 The preferred alternative at this site is full channel restoration. The existing gabion baskets will be removed and replaced with armourstone walls.

Gabion baskets are the metal baskets filled with rocks, and they are more prone to shifting and movement than armourstone, which are large, solid rectangular chunks of rock.

Creek bank gabion basket

While this replacement will help prevent the further risk of erosion and help to protect the creek bank and nearby properties, another concern with this section of Clair Creek is flooding. In the full erosion report included as Appendix L for the study, the portion related to this project also notes:

City to consider additional hydraulic study at erosion site CLR-T1-E1 to investigate flow diversion options through storm sewer for alleviating future flood and erosion risks.

As part of the work on Clair Creek at Keats Way, the project team will evaluate the option for putting in a storm sewer bypass along Keats Way to help manage peak waterflow in the creek, and reduce the risk of flooding. This will be evaluated during the design stage of the project.