The Selwyn River's 'unbelievable' decline

Residents in a small Canterbury community are furious about the state of their beloved local river.

The already toxic Selwyn River has reached record low levels, and locals say it's ruined their summer.

The Selwyn River is almost at a standstill at Selwyn Huts, poisoned by toxic green algae and declared too harmful to swim in.

"It's really disappointing 'cause we have lots of fun," one youngster told Newshub. "It's heading into summer, so the weather's going to be really hot and everything but there's nowhere to cool off."

Steve Curtis has been coming to the river for almost 60 years.  He remembers swimming, boat racing and fishing its once famous trout population.

But he says that's now out of the question, with the river the worst it's ever been.

"This is just unbelievable deterioration over the last five-to-six years, and it's really saddening to see the state of the river now."

Years of intensive dairy farming, too much irrigation and back-to-back droughts are to blame for the river's poor condition. According to Government standards the river is wadeable and boatable, but locals disagree.

"It's not what we want as the standard. We want swimmable rivers," says Mr Curtis.

Research shows in just two months the river flow has halved. It's reached a record low, and experts say it's continuing to decline.

Irrigation restrictions are in place and Environment Canterbury says it is working to reduce the amount of groundwater taken in the area.

"That means in the longer-term there is a better prognosis for the Selwyn River," says Tim Davie, chief scientist. "It should be flowing at a better rate, but it will take a while for the groundwater to come through."

But until the toxic water becomes clean, families are forced to cool off at their local swimming pool instead.