Flood Mitigation Program

North End Alignment Update:

Engagement Summary Document:

South Ruckle Open House – Engagement Summary

South Ruckle Dike and Drainage Works
Frequently Asked Questions July, 2024:

1. What is the flood protection being proposed?
   a. The City is preparing to build a dike along the west edge of South Ruckle to protect against overland flooding and a drainage network along the rail right of way to help remove excess water due to high groundwater and stormwater. The preliminary layout of these works is shown in the Schematic Design linked here:  WP3 Dike and Drainage Network – DRAFT
2. What size of flood does this protect us against?
   a. The dike is designed to protect against a “200-year” flood, which is larger than the 2018 flood. With a 0.5% chance of this level of flooding any given year, there is about a 12.5% chance of it occurring during a 25-year mortgage. Note that this probability is based on historical flood recurrence and cannot be a prediction of the timing of the next major flood.

   b. This design flood was modeled using new tools including a watershed model, climate models, hydraulic model, LiDAR elevation data (laser detection and ranging), and ground and river surveys, following provincial engineering standards. The 2018 flood was used as a reference point to calibrate the model but is smaller than the design flood.

   c. The dike will be built 60 cm (2 ft) higher than the design flood to accommodate uncertainty and have a factor of safety. This “freeboard” is required in the provincial dike standards.

3. When will construction start and finish?
   a. Some preparatory work is planned this year, and the intent is to complete in 2025. Further design and permitting is needed before a detailed timeline can be presented.
4. Why couldn’t the work start earlier?
   a. The DMAF grant application was submitted at the beginning of 2019, and funding agreements were not confirmed until late 2019. The City then needed to hire consultants and engineers, initiate detailed design and permitting, and complete land acquisition before any construction could begin.

   b. Separate funding was sourced for riprap in early 2019 to prevent potential loss of 9^th St and several properties. This riprap will be included in the future dike development.

   c. During the schematic design, Council adopted the “Program Charter” which prioritized projects according to the amount of critical infrastructure and urban area protected. The 19^th St erosion protection (WP5) was advanced because of threat of erosion, and fish habitat offsetting (WP7) was needed to meet permit requirements.

   d. Each of the work packages in the FMP is far larger than most capital projects in the City, and in some cases are larger than the City’s typical overall annual budget.

   e. With WP1 (Downtown) and WP2 (North Ruckle) complete, and WP2c (Downstream Industrial Dike) well underway, the City is ready to proceed with detailed design and permitting of WP3 (South Ruckle Flood Protection).

5. How is the City paying for this? Will it cost taxpayers any money? How much will it cost?
   a. A grant from the BC Community Emergency Preparedness Fund (BC) is contributing $5,000,000 towards the project. The City and other funding partners paid for some of the costs before the grant was applied for, and Council has authorised a small amount of funds for any costs not eligible under the grant and for contingency. The estimated cost of the project including contingency is about $5.2 million.
6. Who will do the work?
   a. The City will run a competitive procurement process to select a qualified contractor, following the City’s Procurement Policy.
7. What will the dike look like and how high will it be?
   a. The dike will be built to Flood Construction Level plus 15 cm (6 inches) for the gravel path surface. The result will be a dike that is generally 1m to 1.5m above the ground elevation, depending on the local topography.

   b. The dike is proposed to be a low profile trapezoidal earth berm dike which will look similar to, but shorter than, dikes already constructed in Downtown and North Ruckle.

8. How will the new work tie into the 2019 riprap?
   a. The 2019 riprap was built to accommodate a dike behind it, and this has been incorporated into the design.
9. Is the community garden protected?
   a. Yes, the dike is designed to protect the properties on the west side of 10^th St, including the Community Garden.
10. Will the dike be a path?
    a. At the north end of the dike, the trail to the Community Garden is proposed to be elevated on the dike from near 10^th St to a point west of the Community Garden. The dike above the riprap is designed to be a path as far south as 63^rd Ave.
11. How does this affect new building in the floodplain?
    a. In the City’s 2022 Official Community Plan, protected floodplains have different planning policies and fewer development constraints than unprotected floodplains. Council will be evaluating further updates to the Floodplain Management Bylaw later this year.
12. Will the community garden trail be closed during construction?
    a. The City will work with its contractors to minimize impacts on use of the trail.
13. What will happen with the memorial benches?
    a. There are several benches along the dike alignment. Where the benches are memorial or were donated, donors will be consulted about potential locations. There are opportunities to have benches on or near the dike.

    b. There are opportunities for the pathway from the dike to ramp down near 64^th, allowing access directly to the benches from near 64^th Ave / 9^th

14. Will more trees be cut down?
    a. In some locations, trees may be cut down. Staff will work with the engineers to minimize losses of trees and replace them with new trees where appropriate.
15. What about the noise and dust?
    a. The contractors will work in accordance with City noise bylaws and the City will work with contractors to ensure dust suppression measures are used.
16. How will people know which areas to avoid during construction?
    a. Similar to Downtown and North Ruckle, construction fencing will be installed along the perimeter of the construction site as a visual and physical barrier to keep public safe from construction. Site signage will identify closed areas and any detours if available.
17. How will we stay informed?
    a. All project updates and presentations will be posted to grandforks.ca/FMP. Email any questions to fmp@grandforks.ca.

    b. Staff will directly contact affected properties with regards to any design change and will maintain a regular email update to residents and property owners during construction, in addition to general project communications.

Flood Mitigation Updates