Extensive stormwater improvements are being made as part of the project to ensure that water run-off from the highway is collected and treated.
For example, as part of the Princess Street improvements a new stormwater wetland swale was constructed at Manukorihi Park. The wetland swale contains special plants that help remove contaminants. Once treated, the water is safely discharged into the stream in Manukorihi Park, which eventually discharges into the Waitara River.
Manukorihi Park stormwater swale shortly after being planted.
These stormwater improvements will result in an improvement in the quality of water that flows from the roads into local waterways.
During construction, we are taking measures to ensure that contaminated doesn’t make its way into local waterways.
Through the process of constructing the roundabouts, rainwater and groundwater need to be pumped out of trenches to allow the team to complete their work. This water contains sediments from the ground so before we can release it into the stormwater network, we need to treat it.
We treat this water using tools like the Siltmate which filters out the sediments before releasing the now clean water into the stormwater network.
Siltmate in use.
If you have questions about how we’re working to minimise our environmental impact, email us at w2bb@nzta.govt.nz.
