Waikato Expressway wildlife and native plant haven almost open for business

A 4ha wetland which will be a haven for wildlife and native plants is taking shape as part of work on the Huntly section of the Waikato Expressway.

The wetland off Evans Road adjoins the southern end of Lake Kimihia and is being developed out of an existing degraded swamp that had been grazed by stock for many years.

The work requires digging out 30,000 cubic metres of clay to form the open water area and the planting of 50,000 wetland plants.

“Our job is to turn it back into a high quality wetland that will support a variety of wildlife and plants,” says NZ Transport Agency delivery portfolio manager Peter Simcock.

Auckland-Waikato Fish & Game will be assisting throughout the transformation and will also be caretakers of the completed wetland.

“We have designed a 4ha wetland that will have several zones that can all cope with varying degrees of flooding,” Mr Simcock says.

“The largest part of the wetland is open water to encourage ducks and other wetland bird species to make it their permanent home. This main body of water will be approximately 3.7ha and the remaining 0.3ha will consist of differing zones of planting that can be on both dry land during the summer and have wet feet during the winter.” 

A barrier will keep the wetland above the normal level Lake Kimihia, a large lake under the care of the Department of Conservation. This is to keep pest fish species out of the wetland and assist water quality. A gate will be installed to allow for the removal of any pest fish species that may enter the wetland during large floods.

”Work on the wetland began recently with a stream diversion first. Ecologists carried out intensive fishing of the old stream that needed to be diverted and native fish species were caught and transferred. Pest species that were caught, including 98 carp, were destroyed,” says Ecologist Keith Hamill.

Nearly 300 tuna (freshwater eels) have been transferred to a safer area.  Most were the short-fin species but endangered long-fin eels were also found. 

The wetland construction will continue during February and March with an expected completion in April. When the Huntly section is completed the wetland will be around 500 metres from the highway.

The work is part of an ecological plan developed by the Transport Agency in collaboration with Fish and Game.

Work is progressing well at the wetland site.

Native tuna (freshwater eels) found and relocated during construction.