The Akaroa Wastewater Working Party reconvened for a single session on November 20 and then went into recess.
Council staff explained that readings from the replacement Akaroa Wastewater flow meter indicate there is twice the amount of water recorded by the faulty old meter, much of the increase attributed to storm and ground water infiltration into the sewer pipe network. Although work will be carried out to reduce infiltration, this is difficult and costly because of the number of places and ways in which infiltration can happen. The overall implications are that the new treatment plant will need to deal with double the volume previously planned for, and if land disposal is used for all the treated water, twice the land area will be needed, and more than twice the storage pond size.
Council are now investigating remote headland sites at Hickory Bay and Redcliffe Point - further from Akaroa than had previously been considered. The previous options are also still retained, including the populated valley sites of Takamatua and Robinsons Bay as partial options, despite the space needed for the increased storage pond size.
The Working Party aims to reconvene in February when data on wastewater volumes over the much busier summer period has been correctly measured.