Stormwater

Stormwater Infrastructure   l    Stormwater Catchments

As the District’s population increases (by approximately 10,000 in the next decade), so does the impact on our environment. For every building and every road, there is less land to absorb the rain and runoff, potentially causing localised flooding or increasing the pollution of our rivers and streams. 

With much of the District being relatively low-lying and criss-crossed by watercourses, the management of stormwater to ensure that development does not upset the delicate balance of the natural environment, is vital.

In addition, when it rains the impermeable surface areas (roads, driveways) are unable to absorb the runoff which is likely to be five times greater when grass is replaced by these urban surfaces. If not managed well, this run-off may contribute significantly to downstream flooding and pollution.

Of particular focus for the Council, are the greenfield developments in Hingaia and Takanini.  Development of these areas will necessitate the construction of new stormwater disposal systems and developers in these areas will build the new stormwater disposal systems to cope with the expected growth and to reduce the effects of increased runoff.

Our stormwater infrastructure

The public stormwater network is operated and maintained by the Council. The network includes approximately 194km of pipe, 32km of open channels, 448 inlet/outlet structures and 3,202 manholes. There are stormwater treatment ponds at Rangi Road, Spartan Road, Oakleigh Ave, Te Koiwi Reserve and Tana Merah Drive. 

We need to maintain the network and to keep the pipe lines repaired or to replace them when damaged so that water can flow easily through them. The stormwater networks flow into our streams and the Manukau Harbour, taking any road pollution and rubbish downstream. In times of very heavy rain, it is likely that some areas may experience local flooding and the Council is working on ways to minimise the problems. We are progressively identifying where larger pipes are needed, or where stormwater treatment ponds are more appropriate.

A list of proposed maintenance and renewal work can be found in the Council’s Long Term Council Community Plan (LTCCP). You can view a copy of the proposed schedule, or contact our Customer Services Centre for more information.

If you have any stormwater problems including blocked pipes, localised flooding or contaminated waterways, please contact our Customer Services Centre or telephone 09 295 1300 to report the problem. Our Customer Service Centre will then pass it on to the Stormwater Engineer for review and remedial action where appropriate.

Stormwater Catchments

All Catchment information is in PDF format.

Please note, you will need Adobe Acrobat Reader installed on your computer to view these documents. If you do not have a copy installed, you can download it here. The following documents are large files, Please right click and save 'target as'.

Hingaia Stormwater Catchment

Hingaia Stormwater Catchment Drawings

Hingaia Stormwater Catchment Appendices

Hingaia Stormwater Catchment Stage One

Hingaia Stormwater Catchment Stage One Drawings

Hingaia Stormwater Stage One Appendices

Hingaia Stream Catchment

Hingaia Stream Catchment Drawings

Hingaia Stream Catchment Appendices