As Auckland cleans up, ideas about how to cope with increasingly intense rainfall have been pouring in.

Experts have been calling for - for example - a so-called sponge city to soak up water using wetlands, porous cement and green rooves; basics such as making sure pumping stations are waterproof so the electrics don't fry again; and just not rebuilding homes and infrastructure in flood-prone places.

Canterbury University political science professor Bronwyn Hayward co-led the cities and infrastructure chapter of last year's IPCC report and focuses on harnessing community ideas...