Farming’s contribution to water pollution gets a lot of publicity but city waterways are the most polluted:
“Stormwater drains end up in creeks, and creeks end up in bays. Dog poo, litter, all end up in streams, and you might be swimming in the bay the next day,” said National Institute of Water and Atmospheric Research’s chief freshwater scientist, Clive Howard-Williams.
Agriculture is often blamed for New Zealand’s declining water quality, but the country’s most polluted waterways are found in the inner city. . .
This doesn’t excuse farmers from doing all they can to ensure their practices don’t pollute waterways but it does show improving water quality is an urban issue too.
The biggest issue for cities is chemicals and organic matter being discarded down stormwater drains from individuals and light industry that eventually end up in the sea.
“Paints, poisons and explosives are the things . . . that pollute beaches. At the end of the day a goldfish down the toilet is not going to do any harm,” McIlroy said.
Even dog faeces and discarded ice creams contribute to the degradation of waterways and beaches. So does washing the car.
“A lot of that sort of material causes the loss of oxygen, so fish in streams die. There is just too much organic matter and then you end up with bacteria in places where you swim,” Howard-Williams said.
Many people believe stormwater is treated before it is fed into the sea, he said. It is not.
“Stormwater drains play a fundamental role in removing floodwater. But the problem is that they end up in creeks, bays and lakes and it is untreated,” he said.
City folk needed to appreciate where the stormwater drains end up and be aware of the lengths councils went to keep them clean, he said. “There is a general lack of appreciation of what goes down the stormwater and where it goes. Urban dwellers have a lot to learn.”
Adverse publicity about rural water quality combined with education have prompted most farmers into taking a much more proactive approach to improving water quality.
More publicity and education are needed to ensure urban people take responsibility for keeping water in towns and cities cleaner too.