New device in war against silted waterways
Posted at 4:37pm Tuesday 13 Oct, 2020
Auckland Council is calling on the latest technology as it focuses on reducing sediment runoff from land development.
Last month Council's Natural Environment Strategy Unit, Sediment Control, principal analyst, Sarah Le Claire, told the Hibiscus and Bays Local Board at a workshop that improvements are needed in how Council monitors small building sites and infill developments in particular.
“Sediment issues on small sites mount up, and we're very aware of the problem in this local board area,” Ms Le Claire told members. “Waterways are suffering and we need to change our approach.”
She said 120 building inspectors had been trained and in the past year, compliance had improved from 90 percent non-compliance to 51 percent compliance.
The local board was also told that Council has identified a lack of consistent, compulsory industry training in environmental management and sediment control issues and is attempting to remedy this, including the possibility of delivering a pilot course.
Key to reducing runoff is a new piece of kit that collects and reports real time sediment monitoring data in areas being developed.
Council's Natural Environment Strategy manager, Dave Allen, told the paper that the prototype sensor device is still being trialled.
“We need to prove the technology works accurately and will work with one or two industry partners to use the sensors and demonstrate the concept,” Mr Allen says. Council hopes that the device, created by Quadbeam, working with Innovate Auckland and Council, can be tested this earthworks season.
“The aim of the device is to improve transparency about the impact of bulk earthworks on water quality.
It is completely voluntary and gives developers an accessible, proactive tool to monitor sediment discharges from their sites.”
He says it will also aim to be a preventative, prompting early “conversations” between compliance staff and consent holders to encourage proactive maintenance of on-site controls and prevent sediment entering the system.
“It's important to note that these sensors will not replace council's compliance monitoring, which is a condition of regular earthworks consenting and monitoring. The device would also not be accurate enough to support any legal action, which is not the aim of the device or the initiative.”
If the trial is successful, Council hopes to introduce the technology throughout Auckland, including in the Hibiscus and Bays area.
Local board member Julia Parfitt asked Ms Le Claire at the workshop for the sensors to be deployed for Nukumea Stream in Ōrewa, in particular, where runoff has been an issue in the past.