Queenstown Lakes District Council’s (QLDC) water supply systems include 17 reservoirs with associated rising and falling mains. Although this technology is well established and robust it is an expensive way to address the needs of an ever-growing community and associated peak water demand.
Water modelling has been used to demonstrate the effectiveness of direct injection as a means to address peak water demand.
Over the last four years QLDC has undertaken thirty to forty exploratory bores and constructed eight production bores. This was in order to either improve existing bore fields, or to provide an entirely new water source.
The overriding principle has been to optimise or re-utilise existing assets rather than expenditure on new and relatively expensive capital upgrades. Wherever possible the opportunity to improve redundancy and resilience has been pursued.
This paper will describe the voyage of discovery - the highs (the excitement of drill rig operators) and the lows (silt, silt and eggy smelling water). It will describe modelling outcomes and present the various solutions now being considered for a number of unique situations in the QLDC area