Visitors pour through the doors at Ardmore Water Treatment Plant’s annual open day


More than 120 people, many of them locals, poured through the doors at our Ardmore Water Treatment Plant’s annual open day on Saturday.  

Watercare southern water treatment manager Nolwenn Lagadec was delighted with the turn-out: “The grey skies and cold wind meant conditions weren’t the best but that didn’t deter anyone and there was a great atmosphere.This year we had a lot of locals from Clevedon and Beachlands, which was a real bonus.”

None were more “local” than Carol and Tony Tucker. They have lived just 200 metres from the plant, in Creightons Road, for 19 years and it was the second time they have enjoyed a public tour.

Carol says every time she visits, she learns something new: “We had one of the plant staff called Graham Head as our guide. He was so good, so informative and he gave us all the information with a twinkle in his eye! It’s a good way of doing it, makes all the details stick in your memory a lot more.”    

Visitors had plenty of questions, which ranged from the treatment process itself to how staff coped with the Tasman Tempest weather event in March, when two months’ of rain fell in 24 hours, creating massive slips in the Hūnua Ranges, sending silt and sediment into the dams, creating huge processing challenges for all of Ardmore’s staff.

Watercare headworks manager Joseph Chaloner-Warman was a key part of our response team during the water crisis, which saw Aucklanders being asked to reduce water consumption by 20 litres per person, per day for several weeks while Ardmore staff stabilised the treatment process: “Eight months have passed but I can still remember every detail. We’d never seen anything like it—huge amounts of clay and silt were turning the water into something that resembled a chocolate milkshake and turbidity levels were higher than anything we’d observed in the past.”

Visitors were shown a giant montage of photos from the Tasman Tempest, which included before and after shots of the dam, massive slips and a graph comparing rain levels during the Tasman Tempest with Cyclone Bola.

Once again, Carol Tucker was most impressed: “I had no idea until I saw that graph how much more rain we had during the Tasman Tempest. We were living in Howick at the time of Cyclone Bola and our basement was flooded so I thought the rain was really bad but know I know that was nothing compared to what we had in March.”  

Watercare supply manager, Priyan Perera says the Tasman Tempest has set a much wider operating envelope for the Ardmore Water Treatment Plant: “Ardmore must be upgraded given the new parameters. We’re is improving the plant’s operability by installing ultra violet light dosing into one of the process streams. It will be introduced within the next 12 months and will be the largest drinking water U.V. installation in New Zealand.”  

The event also pushed the plant’s solids handling systems beyond their capabilities. To increase sludge processing capabilities, Watercare is upgrading the dewatering system by introducing a centrifuge and a new filter press.