March 13/2019 – Thunder Bay Prepares for Rain Storm

Temperatures are expected to rise with light precipitation starting overnight on Tuesday. Approximately 20 to 35 millimetres of precipitation is forecasted with rainfall intensifying through the day on Wednesday and finally tapering off on Thursday, overnight into Friday. The public is advised to be aware that there is a threat of localized ponding in low lying areas from possible heavy rain, prolonged rain, and/or snow melt.
The City is getting ready for the rain - clearing storm sewers and putting resources at the ready.

THUNDER BAY – The City of Thunder Bay is getting ready for the weather and potential impacts of the rain forecast for the city.

The City of Thunder Bay reports, “Roads resources are dealing with frozen catchbasin/culverts, ponding water on roadways and potholing patching. As of this morning, there are just a couple locations where we have water encroaching towards the centreline of the roadway, otherwise just localized issues that are minor in nature. Roads staff continues to patrol and review calls when received.

Major drainage ditches, like the one beside the Transit Office on Fort William Road, have been and are currently being assessed to determine the presence of any ice blockages. The assessment of these major ditches has determined them to be full of snow which allows the water to drain normally. All outfalls on these major drainage channels have been inspected and are free from blockages. (FYI – snow is 10 times the volume of water which means that the elevation of the current level of snow in the ditch is 10 times lower when it is in the form of water.)

Roads will continue to evaluate conditions throughout the day and determine if resources are required to address any concerns.

Tonight/Tomorrow

Roads will continue to monitor and evaluate conditions as the day progresses. If determined, resources will be kept after normal operating hours to deal with drainage concerns.

Roads resources are being scheduled to deploy at 2 am on March 14 2019, in preparation to address any impacts from the forecasted rain event this evening. Resources to be deployed include graders, steamers, and backhoes in the event there are drainage concerns. If needed, Sewer & Water resources will be available to assist with dealing with drainage concerns.

FAQ – Spring Melt

1. Water Ponding on Roadway

When calls are received at dispatch or discovered during patrols the location of each incident is reviewed and prioritized. Prioritization is based on the potential for a liability issue to arise from the impact to City infrastructure or private property. If it is determined that there is a low potential of liability or risk arising from the incident it will be listed and assigned to a crew to address. If the risk is high, resources will be assigned to address the concern in a timely manner.

2. Catchbasin Covered by Snow

A resident may call regarding a snow-covered catchbasin with concerns that water will not drain. The past couple of weeks have seen mild temperatures that created spring melt conditions resulting is meltwater tunnelling to catch basin locations. During the winter season snow is left to cover catch basins as it acts as an insulating blanket. During the spring thaw, meltwater will tunnel to these locations and drain normally. Where natural tunnelling does not occur and water is ponding at these locations, resources will be dispatched to address the concern based on a priority basis.

3. Driveway Culvert not Draining/Frozen

During patrols or calls from residents, the location of each incident is reviewed and prioritized. Prioritization is based on the potential for a liability issue to arise from the impact to City infrastructure or private property. If it is determined that there is a low potential of liability or risk arising from the incident it will be listed and assigned to a crew to address. If the risk is high, resources will be assigned to address the concern in a timely manner.

For more information:

Brad Adams
Manager Roads
Engineering & Operations
City of Thunder Bay
badams@thunderbay.ca
Ph: 807-684-2408