Follow up on Sawmill Creek Stormwater Management Pond tour

In early May, OSEAN partnered with Better South Keys Centre to offer a guided walking tour of the Sawmill Creek Stormwater Management Pond led by staff from the City of Ottawa. On behalf of the nearly 50 attendees, we would like to say a huge thank you to Connor and Haitham for sharing their knowledge!

Here are the answers to a few questions which were outstanding at the end of the tour:

Are there fish in the ponds?

Yes, there are fish in the pond. Typically, these ponds contain species like Carp, Fathead Minnows, Brook Stickleback, White Suckers, etc.

Most of the water is diverted from Sawmill Creek to the ponds for cleaning before it is returned to the creek to flow to the rivers. Does that mean that the water in the part of the creek between the diversion and the rejoin is unsafe for wildlife? 

Just before the pond, there is a diversion structure in the creek. The diversion structure or weir (like a ‘wall’) diverts water into the pond. During heavy rain events, the “first flush” gets directed into the pond and any overflow continues above the weir and down Sawmill Creek. This is normal as we don’t want to dry-up the Creek by diverting all water to the pond as that may affect the natural habitat of the area, however, most of the ‘dirty’ water will go into the pond for treatment.

Who sets the criteria to determine a "safe" level of pollution for wildlife in the ponds?

The Sawmill Creek Stormwater Management Pond is sized based on the 2003 Ministry of Environment (MOE) Level 1 or “Enhanced” Treatment, which is to achieve 80% long-term total suspended solids removal. The pool volumes were determined based on the MOE Stormwater Management Planning and Design Manual (March 2003).

What can I do to reduce the harmful effects of rainwater run-off on our streams and rivers?

Visit the Rain Ready Ottawa webpage to learn more.