Promises to build two grassland areas in Melbourne by this year have not been met by the government, the Victorian Auditor General has found.
In 2010, the Department of Environment, Land, Water and Planning committed to establishing a 15,000 hectare Western Grassland Reserve and a 1200 hectare Grassy Eucalypt Woodlands Reserve by 2020.
The reserves were planned to boost Melbourne's native vegetation in the face of expansive urban development.
The initiative was developed under the Melbourne Strategic Assessment program to preserve threatened ecological communities and species, including native grasslands.
A report tabled in parliament by Auditor General Andrew Greaves on Wednesday states that the department failed to deliver the grasslands largely due to delays in acquiring land.
As of December, the department had acquired only about 10 per cent of land for the Western Grassland Reserve, or 1568 hectares, and no land for the Eucalypt Woodland Reserve had yet been purchased.
The findings reveal that the failure to develop the grasslands by the 2020 deadline means it will be a more expensive project should it now go ahead.
The Grassy Eucalypt Woodland Reserve was designed to cover urban growth areas north of Melbourne around Mernda, while the Western Grassland Reserve was to cover south-east of Melton and west of Werribee.
Grasslands help the state's ecosystem by storing carbon, improving water infiltration, reducing soil erosion, and providing habitat to animals.
The report found government changes to the funding model for the grasslands meant the department were restricted in the amount of land it could buy.
Changes to the regulatory framework supporting the Melbourne Strategic Assessment program are likely to help DELWP deliver the grasslands.
However, the Auditor General report says there are not enough resources in place to effectively oversee the developments.