Water update

Cleaner waterways from permeable road surface trial

Our trial on Birkdale Rd using permeable paving blocks instead of a conventional road surface is reducing the velocity and toxicity of stormwater runoff.

The trial along a 30-metre section of road (outside Birkdale Intermediate) utilises filtering layers beneath the pavers to clean and slow down water runoff.

The new system considerably reduces stormwater toxins and helps manage peak flow and floodwater volumes – protecting our sensitive streams.

With our project partners Auckland University, Auckland Regional Council, Maunsell and W Stevenson & Sons Ltd, we’re pleased with trial results to date.

Our infrastructure planning manager Jan Heijs says the permeable pavers system is removing up to 90 per cent of stormwater toxins, which would otherwise flow directly to our streams and harbour.

The pavers and sub-structure have proven to be robust, holding up well to the heavy load of cars, buses and trucks travelling along Birkdale Rd each day.

The system’s creator, W Stevenson & Sons Ltd, is now preparing it for commercial use. A similar solution for residential driveways should be on the market within 18 months.

Jan Heijs predicts permeable paving will be seen more and more around our city in coming years, particularly in parking areas and on residential streets.

Other environmentally-friendly stormwater solutions we’re promoting include the use of rain gardens and rain tanks for non-potable uses such as toilet flushing.