Auckland Council will begin visiting selected properties on Waiheke Island from 31 August to 11 September to check overland flow paths as part of its Making Space for Water programme.
This is practical work that can make a real difference when heavy rain hits.
Overland flow paths are the natural routes stormwater takes across the ground when pipes and drains reach capacity. They can run across both public and private land, helping move rainwater safely through neighbourhoods. Across Auckland, there are an estimated 79,000 kilometres of these pathways.
Since the assessment programme began in 2024, council has visited more than 3,500 properties across Auckland.
On Waiheke, selected properties are being visited because council maps show an overland flow path may cross or pass close to the property. Having a mapped flow path on or near a property does not mean it will flood. The visits are about checking that stormwater can move through the property safely during heavy rain, as intended.
Sometimes, there will be nothing to do. But where an issue is found, Dean Yee, Network Integrity Manager, says residents will receive clear, practical advice, with voluntary action encouraged as the first step.
“Obstacles such as fences, structures, landscaping, vegetation or stored items can block or redirect an overland flow path. Gutters, downpipes and drains that are blocked or not working properly can also contribute to water building up or changing direction. In the wrong conditions, this can increase the risk of surface flooding and water getting into homes,” says Yee.
Keeping these pathways clear is particularly important on Waiheke. Unlike many parts of Auckland, much of the island has a limited reticulated stormwater network, so rainwater relies more heavily on natural overland flow paths during heavy rainfall.
Diagram showing best practice of how to prepare a property for heavy rain.
The assessments are one part of wider work to reduce flood risk on the island. Council is also progressing improvements in the Blackpool stormwater catchment, including proposed works to widen sections of the stream and upgrade culverts to improve the movement of stormwater through the low-lying area.
Waiheke Local Board Chair Kylee Matthews says reducing flood risk requires council and the community to work together.
“Our community residents have invaluable local knowledge about their land and environment.
“Council must invest in a public stormwater network and working in partnership with property owners, combining infrastructure improvements with practical property maintenance such as clearing gutters, downpipes, drains and overland flow paths, will help us manage flood risk more effectively now and into the future.
Council is responsible for managing and improving Auckland’s public stormwater network. Property owners can play an important part too by looking after private drainage and keeping overland flow paths clear.
Together, these small but practical steps can help stormwater keep moving where it is meant to go – reducing the risk to homes, properties and neighbours when heavy rain arrives.