Volcanic cover deposits and streamflow behaviour in the Central North Island of New Zealand

Abstract

Distribution in time and space of the catchment-outputs of water, dissolved matter and suspended matter of streams in the Lake Taupo basin of New Zealand has been investigated. The hydrological data base is formed by a small number of instrumented sites and relatively few gaugings on streams, that were not instrumented permanently. It appears that the Lake Taupo catchment can be divided into regions with similar flow- and concentration duration characteristics. The forcing factor behind these flow duration characteristics is the presence of unconsolidated volcanic cover deposits in the catchment of a stream.