A map of the high ecological value waterways and water dependent ecosystems for the Hornsby LGA was prepared by the Science Division of the Department of Planning, Industry and Environment, with input layers and support for the map provided by the former NSW Department of Primary Industries-Fisheries and Department of Industry-Crown Lands and Water. The basis for the map arises from Science Division inputs to strategic planning processes. For example, the map has been included in the Land Use and Infrastructure Implementation Plans for the Wilton (Wilton2040, page 22) and Greater Macarthur (interim plan, page 36) Priority Growth Areas. This map was specifically developed for input to Local Government Local Strategic Planning Statements to support Council’s delivery of Strategy 25.1 of the Greater Sydney Region Plan.

The map shows areas where waterways and water dependent ecosystems are defined as high ecological value, based on definitions, guidelines and policies under the Environment Protection and Biodiversity Conservation Act 1999, Biodiversity Conservation Act 2016, Fisheries Management Act 1994 and Water Management Act 2000. Water dependent ecosystems are defined as wetlands, and flora and fauna that rely on water sources (including groundwater). The map represents an overlay of 39 indicators being used by the State Government to define high value, however, not all 39 indicators will be present in any one LGA (see Attachment 1 below). For example, there are 22 indicators making up the map for the Hornsby LGA. It should also be noted that the individual indicators have not been ground-truthed and it is recommended that field assessments and/or a comparison to local mapping be undertaken prior to any decisions being made. The map was created by initially placing a 1 ha (to correspond with a lot size) hexagon grid over the LGA, and attributing the grid with the area, length and/or frequency of occurrence of high value water dependent ecosystems. The purpose of the map is to identify strategic planning priorities for protecting and improving the health of high value waterways and water dependent ecosystems in the LGA. Once identified, the priorities can be used as a basis for identifying aquatic biodiversity refugia, stream rehabilitation efforts and setting management targets and/or land use planning controls that would protect or improve the health of waterways and water dependent ecosystems so they provide the essential services and functions expected of a cool blue-green corridor.