Hold on... A few things stand out to me.
Why do you think they want people to buy energy? (Regulated)Hydro companies always want people to conserve electricity because it means they don't need to be constantly upgrading the transmission grid.
Secondly, what would they be diverting water to? Who is they? Hydro may physically control the dams and valves but if you are saying the water needs to go to the data centre when the water is going to come from Metro Van water department, in which case the city does get a say because development is only approved if there is enough capacity. If the data centre is using a lot of water, so much so that it will impact HydroBC in terms of lower reservoirs, it's going to be a massive demand in the city run water service.
If you have questions about how these things are controlled I'd be happy to help answer them using the public documents from these utilities.

This is a positive step and something that seems rather basic but unfortunately isn't common.
I work with municipalities in Ontario, Canada. I was surprised to learn that only Toronto is required by law to maintain a lobbyist registry. Some municipalities have it in their bylaws and do so voluntarily. That still relies on individual staff knowing and understanding the requirements. I've been surprised how many times I've had to say, "Hey, should this meeting be registered?" and for municipal staff to have no idea it was required or how to comply.