DIE GEBRUIK VAN DIE INSET-UITSETIEGNIEK OM DIE TOTALE EKONOMIESE GEVOLGE VAN WATERBEPERKINGS VIR GEBRUIKERS VAN VAALRIVIERWATER TE BEPAAL

Abstract

Below average rainfall that occurred over wide-spread areas in the RSA during the second half of the seventies caused critically low water levels in certain storage dams. The Department of Water Affairs has therefore been compelled (since March 1983) to introduce water restrictions in various areas. The direct financial consequences of the water restrictions on several sectors and areas were determined during an initial study. In order to determine the total financial consequences of the water restrictions on all sectors within the Vaal River water supply area, the input-output technique was applied during a further study. With this technique, which takes into account the interdependency between sectors, the impact of water restrictions on the total region was determined. The regional input-output model is discussed in the paper. The composition of the total impact per sector and for the area as a whole is also analysed, and the value of water for the various sectors during water shortage situations is indicated. This information can be used inter alia to divide water optimally among sectors and consumers during shortage situations.

Uittreksel

Ondergemiddelde reënval wat sedert die tweede helfte van die sewentigerjare wydverspreid oor die RSA voorgekom het, her veroorsaak dat die stand van sekere opgaardamme tot kriticke lae vlakke gedaal het. Die Departement van Waterwese was daarom verplig om sedert Maart 1983 waterbeperkings in verskeie gebiede in te stel. Die direkte finansiële gevolge van die waterbeperkings op verskeie sektore en gebiede is tydens 'n eerste ondersock vasgestel. Om die totale finansiële gevolge van die waterbeperkings op alle sektore binne die Vaalrivierwatervoorsieningsgebied te bepaal, is die inset-uitsettegniek tydens 'n verdere ondersoek toegepas. Met dié tegniek, wat die interafhanklikheid tussen sektore in ag neem, is die impak van waterbeperkings op die totale streek bepaal. In dié referaal word die streeksinset-uitsetmodel bespreek. Ook word die samestelling van die totale impak per sektor en vir die gebied in geheel ontleed en word die waarde van water vir die verskillende sektore tydens watertekortsituasies aangedui. Dié inligting kan onder meer aangewend word om water tydens tekortsituasies meer optimaal tussen sektore en gebruikers te verdeel.