[bavcyc]

Interesting.

The Gorge in OR has the sunken markers and I've yet to see one show up missing during the snow season.

Wonder if there is specific method to install and also for applying the snow plow to cause the reflectors to stay in place.

[stan_rogers]

I don't know about the whole of PEI - I only lived in the Summerside area for a little over a year, or two winters' worth, before the Canadian Forces Base closure was announced - but in my experience snow was not anything like occasional (or vertical, for that matter; precipitation is a horizontal phenomenon) and ground stability is an old civil engineer's wife's tale. The island is essentially a waterlogged sandbar with a plastic surface that almost seems alive during the frost season. Shallow roadbeds ripple with the seasons; deep concrete slabs tend to shift significantly. (The slab-bed highway around Charlottetown looked like a post-earthquake scene in the spring of '89, and a brisk business was being done in tires, wheels and steering and suspension parts.) There isn't a lot that works well "everywhere" that's directly transferable to PEI. The only way to make sure that inset features stay inset is to sink them deep enough to be more or less useless.