HEVAE Vegetation Groundwater Dependent Ecosystems Value - Namoi

NSW DoI Water has adopted the Guidelines for Identifying High Ecological Value Aquatic Ecosystems (HEVAE) framework developed by the Australian Commonwealth Government. In the current assessment for NSW, the HEVAE consists of four key criteria which include diversity, distinctiveness, naturalness and vital habitat. Therefore, the HEVAE vegetation GDE value layer is a combination of four individual criterion layers. The final or overall HEVAE score was determined for vegetation PCT polygons which has a high probability of being groundwater dependent. This was calculated by adding together the final scores for each criterion (Naturalness, Diversity, Distinctiveness and Vital Habitat). This score was then standardised by dividing by the maximum combined HEVAE score for a whole catchment’s vegetation GDE polygons to provide an even spread of score outcomes between 0 (lowest) and 1 (highest). For ease of data modelling and management, the dataset was divided into the following catchment management areas; Border Rivers-Gwydir, Central Tablelands, Central West, Hawkesbury-Nepean, Hunter-Central Rivers, Lachlan, Lower Murray Darling, Murray, Murrumbidgee, Namoi, Northern Rivers, Southern Rivers, Southern Tablelands, Sydney Metro and Western Division (MDB and far west subdivided further into the IBRA Sub regions).