Upper Collie water allocation plan

This plan describes how we will allocate, manage and protect the Upper Collie water resources.

Last updated: 25 January 2023

Plan release information

The Upper Collie water allocation plan was released in August 2009.

Supporting documents for the plan are also available:

The statement of response summarises our response to comments and questions we received on the Upper Collie water allocation plan: draft for public comment, released in 2007.

The plan includes allocation limits, which define how much water is available in the upper Collie plan area. It describes how we will allocate and manage water resources and will monitor, measure and evaluate the objectives of the plan.

You can view the Upper Collie water allocation plan: Evaluation statement 2009–2017, which evaluates how the objectives of the plan are being met and includes updates to policy in the plan.

As a result of our changing climate, the department has reviewed the allocation limit from Wellington Reservoir. The revised allocation limit from the Wellington Reservoir is 68 gigalitres per year to respond to lower rainfall and inflow. Further information on the decision to amend the allocation limit is provided in the Wellington Reservoir allocation statement and Wellington Reservoir modelling: Re-evaluating the yield and salinity levels.

Water allocation planning in the Upper Collie

The plan provides clear and consistent direction to current and future water users and addresses allocation issues. Careful, long-term planning is needed to ensure that the needs of the community and the environment are protected while ensuring secure water supplies.

Plan area

The Upper Collie catchment is about 200 kilometres south of Perth.

The plan area is within the Collie River Irrigation District and covers the Collie groundwater area. It extends from the upper reaches of the Collie River catchment and ends at the Wellington Dam wall.

Water resources

The Collie River runs through the plan area and is fed from its major tributaries – the Harris River, Bingham River, Collie River East Branch and the Collie River South Branch.

The Wellington Reservoir on the Collie River is the largest reservoir in the South West. Water in the Wellington Reservoir is of marginal quality and the department is working to restore it to fresh water quality.

The major groundwater system in Collie is the Collie Coal Basin. This is made up of the Premier and Cardiff sub-basins. Coal is mined from the Collie Coal Basin through open-cut mining, which results in the need to dewater, which uses large volumes of groundwater. There is a high demand for surplus mine dewater because third parties, such as the local power industry can use it for cooling purposes.