Then and Now: Kimihia Mine (1978) and Kimihia Lakes (2021)

From a landscape assessment in the late '70s to a large-scale rehabilitation today, Boffa Miskell has a long history of involvement with this former open-cast mine.

Kimihia Lake is around 5km northeast of Huntly, in the Waikato. It’s one of the region’s riverine lakes: an extensive wetland system that includes Lakes Whangape, Waahi, Waikare and the internationally significant Whangamarino Wetland. The lakes are linked to the Waikato River, and the wetland system is one of the most important freshwater habitats in New Zealand.

Kimihia Lake was approximately 280ha in size before mining of the site began. During the 1950s, the lake was partly drained and drastically reduced in size to allow strip mining of coal in the lakebed. In 1978, then-Boffa Jackman & Associates prepared a landscape assessment of the open-cast mine area, and landscape design proposals for the end-of-use of the mine. The report included planting studies, and the preparation of planting guidelines for the rehabilitation works.

What remains of the original Kimihia Lake is located on the eastern side of the Waikato Expressway. The former Huntly East Mine site is contained within what was once an area of the lakebed. Since the mining operation ceased in 2017, this area is refilling naturally.

The site is now owned by a local family who have the vision of developing it into a multi-purpose recreation, education, conference and natural park facility based around the future freshwater lake formed by the naturally filling coal mine pit.

The rehabilitation of the site will be programmed to align with the progressive filling of the lake which is estimated to take up to 30 years. The rehabilitation will recreate some of the former ecological values of Kimihia Lake and recognise the cultural values that remain in this area. Rehabilitation work will comprise riparian planting alongside the future lake edge; with amenity and ecological restoration of the streams, wetlands and bush clad gullies on the lake surrounds and wider catchment.

Bryan Sanson is the lead on this project. He says, “I didn’t know Boffa Miskell’s involvement with Kimihia Lake extended back to 1978. It’s pretty amazing to see the hand-drawings from that original report side-by-side with what we’re creating today using modern drafting and graphics software packages.

“The similarities in the vision for what the site can become — even though there’s over 40 years between the two projects — really illustrates that the way Boffa Miskell approaches the landscape has been around since the beginning and what we view as a successful outcome still endures.”