The Shire of Nillumbik was formed in 1994 with conservation of the Green Wedge as its strategic focus. 

The Nillumbik Green Wedge covers 91% of the total Shire area and is distinguished from others by the quality of its environment and natural bushland.  It is these environmental qualities: topography, dense bushland, isolated spaces, rivers and streams and the diverse townships that create a sense of place and continue to draw people to settle in Nillumbik.

The Nillumbik Green Wedge is in the catchment of the Yarra River and is bordered by the Plenty River in the west and the Yarra River in the south and south-east. Three major creeks run through it: Diamond Creek, Watsons Creek and Arthurs Creek. There are significant natural wetlands such as those along the Yarra River in the south-east and Running Creek Reservoir to the north of Arthurs Creek. As well as natural waterways, the Nillumbik Green Wedge is the location for key parts of Melbourne’s infrastructure for potable water storage.

The Nillumbik Green Wedge supports a diverse range of species and their habitats. It is home to 1,000 indigenous flora species, 64 of which are listed significant species. Supporting and often relying on the plants, are 342 indigenous fauna species, 63 of which are listed as significant species including the distinctive Brush-tailed Phascogale, Lace Monitor, Bandicoot, Sugar Glider, Wedge-tailed Eagle, Eltham Copper Butterfly and Platypus.

During 2007 Council consulted with the community to find out what people value about the green wedge and how they see its future.  It is clear that people have a strong attachment to the Green Wedge and, in particular, to its:

• Biodiversity
• Cultural heritage
• Space and landscapes
• Community spirit
• Local identity

Community values shaped Council's Green Wedge Management Plan. This plan directs the management of the Nillumbik Green Wedge in relation to all strategic planning and land use of the non-urban areas of the Shire.