The landscaping company at our townhouse complex has advised that we apply Merit to our lawns to head off the chafer infestation. I've been doing a bit of research on chafers and the use of Merit, and what I've found makes me think the stuff should not be applied anywhere in the city, or beyond.
1) The City of Burnaby strongly prefers the use of biological treatment using nematodes, and says "chemical treatments should only be used as a last resort."
2) The BC provincial government's restrictions (45KB PDF file) on the use of Merit include the following:
"Do NOT apply product or plant treated seed pieces within 15 meters of well-head or aquatic systems, including marshes, ponds, ditches, streams, lakes, etc."
"Do NOT apply to terrains where surface run-off may enter aquatic systems."
"Do NOT mix, load, clean equipment within 30 meters of well-heads or aquatic systems."
The info sheet also says, "This product is highly toxic to aquatic invertebrates. This product is toxic to birds."
3) The manufacturer of imidacloprid, (95KB PDF file) the insecticide in Merit, also says "this product is highly toxic to aquatic invertebrates."
All surface run-off eventually enters aquatic systems, be it directly, through the ground, or via storm drains. I think the various levels of government should be taking a stronger position on this issue and ought to increase monitoring and enforcement.
Our townhouse complex sits right above the Byrne Creek ravine, and diligent work by streamkeepers and the city has actually resulted in improving water quality in the last year as measured by aquatic invertebrate surveys (bug counts).
It would be a shame to see that go to waste. The coho and chum salmon fry (babies) that are popping out of the gravel now need those bugs to survive, not to mention cutthroat trout and other water animals.