The Canterbury Regional Council has unveiled its proposed long-term plan.
The seat was vacated by former councillor Tamatha Paul, elected to Parliament last year for the Green Party.
The Government will "still have to find a way of recognising the Māori interest in water", the Labour leader says.
"It doesn't add up, it doesn't make sense and it's going to result in higher rates," said McAnulty.
"I haven't heard anything about how they're actually going to increase the capacity of the market."
Labour is warning of "certain" rate rises - but the PM says he's "not taking economic lessons" from the previous Government.
It's just been announced by the Local Government Minister.
Mayor Tory Whanau has met the local government minister on the city's troubled water network.
The email was requesting private information about council staff such as their names and addresses.