Streetcars often have a lot of sand on the floor behind the driver

Dear Urban Decoder: Streetcars often have a lot of sand on the floor behind the driver. What gives?—Connie Rodriguez, Earlscourt

Blame the beach-like conditions on the overflow from large sandboxes located under the first seats on either side. But (sorry, kids), they’re not that kind of sandbox. You see, streetcar wheels and rails, for all their cast-steel strength and durability, suffer from one potentially fatal flaw: they don’t get much traction, especially when autumn leaves and winter ice enter the equation. To solve this slippery engineering problem, streetcars are equipped with a system that sprays fine-grained sand onto the rails just ahead of the forward undercarriages (if you look closely, you should be able to spot the 2.5-centimetre-wide nozzles). Providing a rough surface for the wheels to grip, the sand is deployed automatically whenever traction is poor or when the driver slams down on the brakes. It can also be sprayed manually, at the push of a large, mushroom-shaped red button on the dashboard (and you thought it was for the ejector seat). Sandboxes are filled over at the TTC yards’ “sand shack,” a kind of giant funnel that dispenses the stuff into buckets. If the attendants get a little careless when dumping it into the sandboxes, who can blame them? They hand-load streetcars with over 1,500 tonnes every year.