Ruataniwha Environmental Benefits – Yeah Right!
The New Zealand Outdoors Party, the newly formed political party, is challenging pro-dam organisations to substantiate claims that the proposed Hawkes Bay Ruataniwha dam is good for the environment. “Rural News and Andrew Curtis of IrrigationNZ are two sources of recent rhetoric in which environmental benefits of the dam have been lauded. Andrew Curtis of IrrigationNZ is, as usual, behaving to type, but we were surprised by the Rural News editorial of 20 July 2016, given their diverse and informed readership” said Co-Leader David Haynes.
Haynes continued “Our researchers have spent some time analysing the publicly available environmental assessments on the proposed dam commissioned by Hawkes Bay Regional Council. During construction sediment discharge downstream and loss of access is anticipated for nearly five years. Once constructed, loss of galaxid habitat by inundation, blocking of passage for spawning eels and trout, loss of spawning sites and nuisance periphyton growth were highlighted by the reports. Additionally, immediately below the dam, a 50% reduction in invertebrate habitat caused by short-term flow fluctuations and 100% loss of rainbow trout spawning areas in the Makaroro and Waipawa Rivers was identified along with reduction of survival and/or growth of trout due to reduced in-stream food and increases of nitrogen and phosphorus pollutants of 81% and 41% respectively. The formation of a stillwater fishery has also been characterised as one where the current average size trout will be superceded by smaller trout.
“The good news appears to be limited – Stillwater habitat creation for some native fish and trout albeit at the loss of flowing-water habitat for these and other species, improved low flow levels but only if existing water allocation holders agree to forego their free resource for purchased Ruataniwha water, higher low summer flows but at the expense of reduced median flows and flushing flows which should scour undesirable periphyton growth. Unfortunately, the latter may not occur now that irrigators may be given contractual preference over environmental flows.
The Opus report on Recreation Assessment is similarly bleak – suggesting building a cycling track alongside the irrigation intake stream as a recreation opportunity for the dam, despite the fact that these two projects are wholly independent of each other. Opus also acknowledged recreational opportunity in the formed reservoir would be compromised by the lake level’s frequent fluctuations of up to twenty metres, leaving a ‘dead zone’ around the lake periphery.
“Even with extensive mitigation recommendations there will be a net loss of environmental values to the Tukituki catchment. All in all it’s another example of tax and rate payer funded freshwater vandalism.” concluded Haynes.