Better management of flood risk

New Zealand communities don’t understand flood hazard risks but expect them to be better managed and resourced in future after this year’s major events, this month’s Environment Waikato Operations Committee meeting heard.

Asset Management Group Manager Scott Fowlds said the need for improved flood risk management was growing, as continuing development pressure occurred in flood risks areas. Recent floods in the Manawatu and Bay of Plenty clearly illustrated the limitations and risks of structural flood protection measures alone, and that at times river floods would exceed protection measures and the ability of local communities to cope.

He said ever increasing pressure on land for development, including areas at risk from flooding, and a public expectation that flood risks would be better managed in future compounded the issue. Good information on flood risks and communication to the public was required.

Regional councils and the Ministry for the Environment were developing new directions for river flood management at a national level, and Environment Waikato was supporting this development and also assessing flood risk issues in the Waikato.

He said that before 1988 flood mitigation was strongly influenced and directed by the Crown, funding incentives for flood protection works. The very dynamic nature of rivers and associated flood risks was largely ignored, but a new approach to managing urban flooding had begun, with growing awareness that engineering works were not the universal answer.
A new approach to flood risk management meant decisions should be made for sustainable management in a local context using engineering, land use, flood warning, emergency management, catchment management and community awareness.

Issues which needed addressing included communities not understanding flood risks, schemes not engineered for ‘super events’, fragmented river management, controlling the river rather than living with it, reluctance to use appropriate building design, and inadequate river system maintenance.

The Waikato is currently facing issues such as demand for development in flood prone areas in Te Kuiti and Ngatea, and on the Thames Coast. Work planned on the Thames Coast aims to provide a comprehensive approach including river and catchment management, building and land use controls, and warning and emergency response measures for major floods which would still occur.

Resolving these issues raised questions about the sustainability of structural flood protection works, allowing development in flood prone areas and the need to manage residual risk.

Mr Fowlds said the national working group would take up to a year to complete a national framework and Environment Waikato would have a draft strategy for a Regional flood risk management strategy by February next year.