The Lower Steenbras Dam also declined, from 48.58% to 47.69%, while Voëlvlei Dam recorded a slight increase.
The provincial head of Water and Sanitation said the water authority will meet for the Annual Operating Analysis Meeting on 1 November to determine water conservation measures.
The department has urged residents to continue using water sparingly, even as some dam levels remain stable.
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Mihle George
www.ewn.co.za