Private stormwater assets
Auckland Council says property owners are responsible for maintaining private stormwater assets on their property. Examples include catchpits, drains, spouting, grates, pipes, roof gutters, detention tanks, overland flow paths, and soakage pits or bores.
If the problem is on your property and involves a private catchpit, driveway drain, stormwater pipe, soakage pit, detention tank, or roof-water drainage connection, a plumber or drainlayer may be the right person to assess it.
Public stormwater assets
Auckland Council owns and maintains public stormwater assets. Watercare also explains that stormwater runoff flows into drains managed by Auckland Council and says concerns about public assets such as drains, ponds, wetlands, or roads should go to Auckland Council.
Driveway channel drain, private catchpit, yard grate, roof-water pipe, detention tank, soakage pit, or stormwater pipe on your property.
Roadside catchpit, street flooding, public reserve drainage, public stormwater manhole, or public stormwater network asset.
When you are not sure
If water is entering a building or creating an immediate safety risk, deal with the urgent risk first. If the asset boundary is unclear, Auckland Council suggests getting in touch when you are not sure who is responsible, and the PGDB register can help you check registered plumbers and drainlayers.