You could say the same argument about food, but the system of privately owned farms moving food via privately owned logistics companies to privately owned grocery shops works very well. Yes, it's the responsibility of the state that it's citizens can acquire their needs, but that doesn't mean it has to be government owned.
The difference being that farmers and logistics companies and shops work in a competitive market where as water in a natural monopoly.
The system does not work perfectly though. In the UK big supermarkets have monopsony power over farmers and smaller farmers are being squeezed out by big farm owners (who tend to have lower standards, especially of animal welfare).
I don't think the Soviet and Chinese examples are very relevant, because dealing with a bunch of peasents is extraordinary different from dealing with an agricultural sector that is already industrialized.
Because the massive subsidies we already have the incentive problems too, so it's not like that would be a new can of worms either.
Subsidies are certainly mismanaged in numerous ways but they are the only alternative to the granary system to maintain reliable and stable food production. We used the granary system for thousands of years across the world and while it kind of worked, it also resulted in numerous famines across every culture.
> the system of privately owned farms moving food via privately owned logistics companies to privately owned grocery shops works very well.
Does it? Food prices are up, millions of people rely on food banks [0], etc. This may not be entirely down to farms or the governmental oversight thereof, but food security is not a given.
Likewise, if it's nationalised, poor water management should result in different voting behaviour, particularly in favor of parties that will improve it.
But I think the other issue there is that for the past 30 years, there hasn't been an issue with the water supply; it's invisible when it's working well, so it doesn't get attention during voting season.
More realistically, if they can't do their job, vote their bosses out of office. The bosses might be a level up from the administration, but someone elected has power to appoint and fire, surely.