HBRIC said yesterday's 52-page decision indicated the board of inquiry intended to grant what HBRIC believed would be "useable production land use consent conditions for the RWSS". Obtaining a "workable environmental consent" from the board is one of four conditions required by the regional council to satisfy a planned investment of up to $80 million of ratepayers' money in the scheme.
Yesterday's decision - amending a handful of resource consent conditions for the scheme and to a related plan change for the Tukituki catchment - follows a High Court challenge to the board's earlier decision, issued last year.
The challenges - from Fish & Game, Forest & Bird, and the Environmental Defence Society - related to the board's approach to the management of nitrogen in surface waters within the Tukituki.
Much of the debate around the board of inquiry's earlier decision has centred on the setting of a 0.8mg/L limit for dissolved inorganic nitrogen (DIN) in the catchment's waterways.
Fish & Game environmental manager Corina Jordan said while HBRIC had proposed farmers signing up to the Ruataniwha scheme be exempt from the 0.8mg/L limit, the new decision from the board required them to manage their land in a manner consistent with achieving the limit by 2030.
Environmental Defence Society chairman Gary Taylor said his organisation was also pleased to see the DIN limit retained but had concerns water degradation could continue through to the end of 2030.
"There are still questions over the viability of the irrigation scheme and we would be dismayed if a scenario unfolds where the dam goes ahead and pressure then comes on to ease the compliance regime to help make it work," he said.
Forest & Bird advocacy manager Kevin Hackwell said it would be irresponsible for the council to invest in the dam "without having proved to their satisfaction that the formidable reductions in nitrogen pollution were possible".
HBRIC chief executive Andrew Newman said 2030 was "a long, long way from now. We believe farming practices and technology will improve substantially over that period of time in relation to nutrient management".
Yesterday's decision gave HBRIC "real confidence that we can continue to move ahead" with other aspects of the project: raising capital, securing sufficient water sale agreements from farmers and finalising a construction contract.
Irrigation NZ chief executive Andrew Curtis said the decision was "a far from practical outcome for farmers and the regional economy. We believe nutrient limits set for the Tukituki system remain unrealistic for what is a productive working agricultural landscape."