Critics of the proposal for a water reservoir dam (at the Lower Maungakotukutuku site for which the council spent a net $1.8 million buying land in 2012, before deciding to go with the borefields and River Recharge instead) base most of their opposition on its alleged cost — estimated by the GWRC in 2010 at about $27 million. However, an opportunity it could provide is for the district’s own hydro-power generation.
When the subject of hydropower dams is mentioned, for many it brings to mind massive examples such as those on the Clutha, Roxburgh and Waitaki Rivers; but they don’t need to be that big to have economic benefit.
This page on the TrustPower website page states:
Arnold Hydroelectric Power Station is sited on the Arnold River and is fed by Lake Brunner, in the South Island of New Zealand. The station was commissioned in 1932 and has an average annual generation output of 25 GWh. A new Trustpower project called the Arnold Valley Hydroelectric Power Scheme is being developed behind Dobson township, with a projected output of 46 MW.
Arnold Station is in a region of high rainfall — it generates at high capacity all year, without need to control the level of Lake Brunner. A dam across the Arnold River maintains the water levels to power the station’s turbines.
Kapiti is also an area of high rainfall, except during the summer months (although that wasn’t true over the 2016-2017 summer).
A future, more enlightened council than the one we have should look at a partnership with a power generation company; providing both local water supply and power.