Waste water now irrigated to land
(Posted on: November 15)
Since Feilding was founded in 1874, the Oroua River has been an integral part of the township both providing water for the town and taking water away.
The Oroua River continues to provide water for the town, but since 31 October2018 Manawatū District Council stopped sending treated waste water to the river and began land based waste water treatment on 2 November.
The waste water is being applied to 115 hectares of land adjacent to the treatment plant in accordance with the consent issued by Environment Court, when the river is in low flow.
Mayor Helen Worboys switched the pumps on that will take approximately six million litres of water per day to the three pivot irrigators. There are two more pivot irrigators being commissioned in the coming years.
The system and daily management decisions has been specifically designed to prevent spray drift and to ensure that the amount of water does not exceed the capacity of the land. In addition to the irrigators there are two 25 million litre ponds that will act as storage when it may not be possible to use the irrigators.
“A lot of testing has been done to ensure there is no drift, we are planting buffer areas around the site, and have increased the distance between the irrigators and neighbouring properties,” says Hamish Waugh general manager infrastructure.
“For the past two years we have been operating the irrigators using fresh water to make sure the land can absorb the water and more importantly to make sure there is no drift. We have several monitoring stations that check everything from weather, groundwater to spray and now have that data and knowledge to ensure the system is effective.
“The water that is being applied is very clean and odour free, and we are constantly monitoring the water, we are also very conscious of perceptions about waste water.”
To get to this stage has taken 10 years and $31m dollars for consenting and new infrastructure investment.
The Oroua river has been named as the best river in the Horizons Region and second ‘most improved’ river in New Zealand at the recent New Zealand River Awards.
“This is due to a lot of work over a long period, and the irrigation to land is just another step that we have taken to improve our river.”
Other initiatives planned to remove more wastewater from the rivers include the waste water centralisation project that will see waste water from our other plants at Sanson, Awahuri, Rongotea, Halcombe, Kimbolton, Cheltenham piped to Feilding for treatment.