Trade waste charging - Nelson case study

Nelson City has a population of approximately 44,000 people with a limited commercial and industrial base. Councils Trade Waste Bylaw was made operative in 2007 establishing two methods for Trade Waste charging. Method A is based on a formula that takes into account the quality and quantity of trade waste discharges and is typically used for larger industrial operators. Method B is based on a formula that relates to the volume of potable water supplied to the property with a correlation factor applied to account for water use that does not become waste water.

The Nelson Regional Sewerage Business Unit (NRSBU) is a joint venture between the Nelson City Council and the Tasman District Council. Trade Wastes from the southern part of Nelson City and the Tasman District are discharged to the NRSBU for treatment at the Bells Island Treatment Plant. The charging mechanism for discharges to the NRSBU was reviewed through the late 1990’s and early 2000’s in order to establish a system that allowed for the fair recovery of capital and maintenance costs and the better allocation of risk associated with funding upgrades. An additional benefit has been an improvement in demand management by the scheme customers.