The Department of Agriculture and Fisheries (DAF) assesses and mitigates the impacts development has upon fish passage. The decision on the importance of a waterway to fish passage (a waterway determination) used to be made by on a case-by-case basis. Although the definition of a waterway is consistent, the characteristics of an individual waterway and their importance to fish passage can be interpreted differently by staff and applicants. In March 2013, DAF released a spatial layer with a waterway determination for every waterway across the State that is considered to be important to fish passage. These waterway determinations are coded into five colours depending on how development impacts upon fish passage, ranging from Purple (major impacts) down to Green (low impacts). The Department now uses this spatial layer to trigger and assess Development Approvals and its use has streamlined the waterway determination process, providing a transparent and definitive determination both in-house and for the wider community. The spatial layer has also enabled the redefinition of a set of self-assessable codes that are used for fish passage under minor works. They are a set of acceptable development risks that the Department is satisfied can occur without the need for a development approval or further fish passage mitigation. With the use of this spatial layer, the codes are now better attuned to the impacts development could have upon fish passage in all five colour-coded waterways.