Pooling and ponding are normal occurrences during rain events and thunderstorms


Ponding and pooling are no strangers to Ottawa streets during snowmelts. But during the spring, summer and fall, it’s just as normal to see them reappear on our streetscapes after major rain events and thunderstorms.

Rain drops

During the year, thunderstorms will roar through the capital, bringing torrential downpours that result in a large quantity of rainfall over a short time period. It makes the catch basins on city streets roadway to go into overdrive – working to their full capacity. This slowly draining the water often causes some pooling and ponding on roadways.

However, if you notice large pooling of water, and it’s still there an hour after the rain has stopped, report it online through MyServiceOttawa – for quick reporting and service-tracking features. If the request is urgent, please call 3-1-1 – especially if you see ponding over an extended period of time.

But as a preventative measure, always make sure the catch basin is free of leaves to help them drain the water during rainfalls.

Some areas of the city are more vulnerable to significant rain events due to geographical features in those areas.

As a result, some catch basins in those areas are equipped with inlet control devices (ICDs), or commonly known as restrictors.

ICDs help manage stormwater when the storm sewer is beyond capacity. They help prevent stormwater pipes from surcharging and backing up into people’s basements. Water is contained on the surface where it will pond but gradually recede as the rainfall stops

Basement flooding during rain events are not always a result of street drainage. Here are precautions that you can take around your home to help prevent basement flooding and water seeping into your home:

  • Sealing window wells and cracks in floors, walls and the foundation;
  • Ensuring that the ground is sloped away from the foundation;
  • Directing downspouts from eavestroughs away from the foundation;
  • Discharging sump pumps to the ground at least 1.2 metres from the foundation;
  • Installing protective plumbing devices, such as backwater valves, which protect against surcharging in City sewers;
  • and maintaining plumbing devices.

You can get more information on stormwater collection and prevention tips for basement flooding on ottawa.ca.