'Water used for domestic purposes’ in Gisborne District: Application of the river values assessment system (RiVAS and RiVAS+)

Abstract

The River Values Assessment System (RiVAS) was applied to the river value ‘water use for domestic purposes’ in Gisborne District, to identify rivers of relatively higher and lower importance for this value. Two national level experts in the field assisted with identifying an initial list of primary indicators that best describe the value – this list was subsequently revised by the local expert value and indicators attached. The final list of six primary indicators is: 1. Number of residents supplied; 2. Quantity and reliability of supply; 3. Chemical/ physical; 4. Microbiological; 5. Climate change; and 6. Cost. Ten rivers were assessed by an expert panel: two, the Te Arai and the Mangapoike Dams stream complex are of national significance mainly because they are the principal water supply for Gisborne city. Three rivers were assessed for their restoration potential via RiVAS+, namely the Waiapu, Mangahauini and Waitakeao. The same two interventions were identified for each, i.e., • Improve riparian habitat - Pest control • Enhance water quality - Remove/fence out stock.

‘Investing’ in these interventions would improve the score for each river but not move them out of their local significance classification.