Our coastal environment is constantly changing as the shoreline moves and sea level varies. These changes become a hazard when they threaten human life and property.
Coastal erosion and coastal flooding are the main coastal hazards in our region. Most of this threat is to buildings located within the zone of natural shoreline change.
The Waikato region’s coastline has about 1,150 km of open coast and shoreline, including estuaries. Our coastline is made up of the following distinctly different areas:
The East Coast has mainly medium-sized estuaries and wide sandy beaches separated by rocky headlands and cliffs. Some open coast beaches are backed by extensive areas of sand dunes.
The West Coast of the Coromandel Peninsula and the Firth of Thames is a mixture of rocky coastal fringe and narrow sand and gravel beaches. The West Coast (from Port Waikato to Mokau) features long sandy beaches, areas of cliffs and dunes and three large estuaries.
Coastal hazards in the Waikato region include:
The main coastal hazards in the Waikato region are coastal erosion and coastal flooding.
Houses are at risk from coastal erosion or flooding in over half of our coastal settlements in the region. The risk from coastal erosion has been caused by building too close to the sea to allow for natural shoreline changes. In many cases coastal development has damaged vegetation and sand dunes that protect the shoreline. Climate change will worsen this situation due to rising sea level, changes in winds, waves and currents, and an increase in the strength and frequency of coastal storms.
Coastal flooding can also threaten ‘lifeline’ services such as water, power, telecommunication and transportation networks.