I have been involved with the people in Calgary who think paving over the Highland Valley is a terrible idea. For me it was as simple as looking at the plans and seeing that they want to build in the valley where a creek that overflows its banks every spring runs. I grew up looking forward to the spring rains. After the long winter the rain would come and everything would be green. That's probably why rain makes me feel happy and optimistic, it promises better things ahead.
Usually the overflow is pretty tame but it's just what a creek running through a park does. There was one spring, in 2007, when the flooding was way more dramatic than normal. It filled up a lot of the park and tore up asphalt. I have some pictures of it that I dug up that I put on Twitter. They're not great but they're a useful historic resource so I'm putting them here too.