The scientists measure and make recommendations, and those recommendations go to government committees, who make the final decision. Those committees are loaded with Quebec representatives (who, IIRC, are guaranteed in our Constitution to always make up 25% of the House of Commons) who are always seeking to hamstring the democratic process in order to maintain their favoured status. In particular they seek to limit any growth of Alberta's political power, as they know it could end the gravy train.
You may think I am overstating the case. I most assuredly am not.
Edit: Here be a link