Managing your flood risk Flood Resilience

Dams are interesting and often under-appreciated flood protection assets. When you think of a dam, you might imagine some gigantic structure like the iconic Hoover Dam in the United States, but our dams here in the Horizons Region are much smaller and more often used to manage flood risk.

Dams are used to temporarily contain floodwater from inundating surrounding streams, rivers and land. They’re not designed to stop floodwater entirely. Instead, they slowly release a controlled flow of water until the dam drains - kind of like how your bath drains when you pull the plug. This helps relieve the pressure on surrounding waterways.

Dams also have a spillway built in, which is a ‘ramp’ build into the side of the dam to allow for overflow. In case the main containment area becomes full and starts to spill over the top, the spillway allows the extra water to flow in a controlled manner into another smaller containment area before flooding the immediate area surrounding the dam.

The Makino Floodgates are located just outside Feilding on the Makino Stream, and help keep rising floodwaters from overtopping the stream, which runs through the middle of Feilding township.

The gates, which can be operated remotely, are closed when required to divert floodwater from continuing along the Makino Stream and potentially causing flooding within Feilding. When closed, the gates redirect water along a controlled spillway and into the Kiwitea Stream instead.

During weather events we work closely with Manawatū District Council to assess whether a gate operation is required. If an operation is deemed necessary, surrounding roads and closed and residents are notified.

Stopbanks may not seem very interesting - but they are vital for protecting our communities against flooding. They are the most simple form of flood resilience asset, and we own, manage and maintain more than 420 kilometres of them throughout the region. This is in addition to the numerous kilometres of stopbanks owned and maintained privately.

Stopbanks help hold back floodwater by giving rivers and streams more capacity to fill up in a weather event without immediately flooding surrounding land. Find information on how to care for your stopbanks, including grazing guidelines, here.

As our biggest and most high-tech piece of river management infrastructure in the region, the Moutoa Floodgates, located between Foxton and Shannon townships, provide communities along the lower reaches of the Manawatū River catchment vital protection from flooding.

We post updates whenever the gates are operated, so keep an eye on our Facebook page or click the 'News' tab at the top of your screen.

For more information about the Moutoa Floodgates, visit our dedicated webpage here.