In the early 1920s New Plymouth City Council purchased land for the construction of a dam and a lake to act as a water catchment area for the expanding city of New Plymouth. In 1932 the lake was created by forming a dam across the valley and submerging 79 acres.
It was named after the Mangamahoe stream which flows into the upper reaches of the lake.
Water from both the stream and the nearby Waiwhakaiho River feeds the lake through a 548m pipe. In order to protect the steep hillside from eroding, development planting was undertaken and shelterbelts were planted to protect the pine trees growing in what is now the Mangamahoe Forest.
The lake itself is also significant to the district in terms of power generation. Trustpower Ltd administers this from the Mangorei Power Station.
The walk takes you on a journey around the lake through production forest, up to impressive lookouts and among mature ornamental tree plantings that are mixed with pockets of regenerated native bush. The circuit walk is an enjoyable one for people of all ages. However, there are some steep undulating sections on the walk that require a reasonable standard of fitness.
The walk may be started at either end of Lake Rd. Along the circuit walk you will meander through a small collection of redwood trees which were planted in 1931. In California, where they originate, they are known as giants of the forest, reaching heights of up to 111m. Redwoods are known for their longevity. The growth rings of fallen trees in California indicate that some have lived for more than 2,000 years.
On the eastern side of the lake the circuit walk gives the choice of two routes:
1) The upper ridge takes you over a forest access road used for logging operations. As this road is up high on a ridge above the lake it provides remarkable views of surrounding farmland, Mt Taranaki and the lake itself.
2) The lower lakeside route takes you on an ambling walk close to the lake edge. Lakeside vegetation and regenerating pockets of native bush provide a cooling atmosphere and a home to many birds. The northern section is a popular area for mountain bikers, so caution is advised on these tracks.