Reasons for closure of Omanawa Power Station

Mon, 4 Feb 2008 21:44:13 -0500

On the 3^rd of February 2008 I received the first e-mail regarding the Kaimai Hydro Development Scheme. I am surprised at the lack of response and have now put it down to two factors:

Hydro generation in the Tauranga region is niche interest topic.
A significant number of people that worked on the scheme may now be relatively old, dead or doddery.

Regarding the email:

David,

I was interested to know who operated this power

station and why did they decommission it ?

Thanks,

Tim

The Tauranga Borough Council initially built and ran Omanawa and Mclaren Falls Power station. Both the Tauranga Electric Power Board and the Tauranga City Council combined their Electricity generation interests to form the Tauranga Joint Generation Committee.

On the 30^th October4 1965 the Tauranga City Council and Tauranga Electric Power Board Empowering Act was passed by Parliament and it gave both parties legal authority to establish the “Tauranga Joint Generation Committee” which amongst other things controlled and developed generation and acted in their interests to purchase electricity.

Once the Omanawa Weir had been built, circa 1974, the water that previously flowed to the Omanawa Station (generation head of 33.5 metres) was diverted to Lake Mangaonui. Then it passed through Lloyd Mandeno, Lower Mangapapa and Ruahihi stations (combined generation head of 151.5 + 35 + 88 = 274.5 metres). Thus about 8 times as much energy could be obtained from the water that previously flowed through the Omanawa Station.

The Omanawa Station ran for a surprisingly long time on reduced inflows (about 24 years) closing in 1998. The Tauranga City Council probably has engineering reports relating to its closure.

Reasons for its closure could include:

The building could be structurally unsound and/or require extensive renovation.
The generation equipment uneconomic to replace or renovate.
The station required 24 hr. manning and this may have become unworkable and/or uneconomic.

I would have liked to see it maintained/mothballed as a historic site for future generations.

First Post

Tue, 16 Oct 2007 05:05:43 -0500

The "Mini Hydero" spelling above is a mistake which amused me.

My other web-sites mainly deal with the Hyde and Hudleston families. But the Wairoa hydro development scheme may attract a wider audience – so I decided to create this blog to let people comment and add additional information.

David de la Hyde