In 2003 Palmerston North City Council (PNCC) was granted consent to discharge treated wastewater to the Manawatū River for a period of 25 years. To meet consent standards a $16m plant upgrade was undertaken to reduce dissolved reactive phosphorus (DRP) in the discharge to limit the growth of periphyton and impact on macroinvertebrates in the river. A significant improvement to river water quality and ecology resulted.
Despite these improvements the regulatory agency initiated a consent review in 2013 on the basis of excessive periphyton growth having an impact on the river’s life supporting capacity and sought to introduce in river conditions for periphyton and macroinvertebrates. This effectively shifts the risk of uncertainty around ecological outcomes onto the discharger.
The Review Panel has issued an interim decision with conditions that the Council is unable to achieve compliance even with major investment in nitrogen treatment but has yet to issue its final decision.
The review process has cost well in excess of $1m and has raised uncertainty for Council’s financial and wastewater planning processes for over four years. This questions the value of the review process in such circumstances and how much reliance can be placed on consents for long term planning.