gnu.. I respect your duties & obligations. I have no quarrel with those who, by chance, end up needing to live in certain places. I simply wonder if those who built there originally knew it was 'a tsunami zone'.

Awhile back, one small town in the American mid-west (Iowa?- not sure) realized they they were likely to be flooded every few years. They moved the entire town! I realize that Edmonton can't do this...but they and others can zone the town so that private homes are NOT built in serious flood areas, and restrict the chancy locations to the type of land use you refer to...or even just parks. Cities which just realized the problem 'could' restrict NEW building and begin gradual relocation as $$$ permit. They could at least officially recognize the situation.
Right now people in New York & New Jersey are rebuilding where Sandy just wiped them out. It might not happen again for 40 years.. or it might in 3 years, given climate change.
Yes... I am aware that some people MUST take chances... and some people choose to take chances for the 'privilege' of living on the edge and daring Nature.... I just wish the odds were, by law, carefully spelled out. This would not do much good in tornado country, but 20 year flood plains are a different story, as are landslide and fire areas, as in California.

This sounds all-too-critical, given that people are suffering... but that IS my concern. *I* waded out of my house in New Orleans in 3 feet of water when I was 9 years old, after a levee failed. Today that street is still teeming with new homes. I know that we cannot keep everyone totally safe....people must live somewhere, but way too little is done to analyze and define acceptable risks. Real estate speculators lobby legislatures for exceptions to zoning restrictions...and many of the results make headlines.

I do hope this current situation eases soon.