The Government's allocated $100 million over the next decade towards cleaning up the country's rivers, but if the Greens had their way it'd be spending billions.
"There have been some huge estimates -- there was one that we saw late last year that said the cost of cleaning up all of our rivers around the country could be anywhere between $4 billion and $7 billion over the course of the coming few decades. It's a colossal cost," co-leader James Shaw told Paul Henry this morning.
Mr Shaw's realistic about the chances of getting $7 billion to make all of the country's rivers and streams swimmable again, so is settling for just 10 that "locals know and love".
"None of them are completely beyond hope… we just need to focus on it," he says.
The Government's goal is to make waterways at least "suitable for wading or boating", which Mr Shaw says isn't good enough, and the $100 million is just a drop in the bucket that won't fix a long-term decline in water quality.
"We started dropping the ball about 20 years ago, so this is a long-running problem. It basically matches the intensification of the dairy industry and also increasing population, particularly in our main urban centres, like Auckland."
In cities he wants more money spent on preventing toxins getting into waterways in the first place.
"In the Lucas Creek in Auckland for example, there are a number of stormwater drains that run into the creek, and there rubbish and toxins that build up in stormwater drains that get passed through into the creek. One thing we'd look at for urban centres… is proper stormwater filters where they do meet the creek, and also managing new development. Part of what's happening is as you get more developments going on, you get soil and heavy metals that get tipped into the creek as well."
And while many dairy farmers are making an effort to clean up their act, there's more many can do.
"You can do things like plant wetlands, riparian planting, increasing fencing along the waterways to ensure that animals don't get into the rivers, and so on."
Mr Shaw hasn't asked Labour what they think of the Greens' policy, but thinks they would "philosophically" be in favour of it.