Setting plan objectives in the Gold Coast water plan
The draft Gold Coast water plan introduces updates to water allocation security objectives (WASOs) and environmental flow objectives (EFOs) to modernise water management and ensure sustainable resource management.
- WASOs focus on providing water security for users
- EFOs aim to protect environmental flows and ecosystems.
Both sets of objectives are supported by performance indicators (PIs) which are calculated using hydrological models. These indicators provide measurable benchmarks to assess changes in water management.
Reporting nodes
Reporting nodes are specific locations within the plan area where WASOs and EFOs are assessed. These nodes serve as reference points for evaluating the impacts if water resource development.
- For WASOs, PIs measure metrics such as the percentage of years a nominal volume is met or exceeded, while objectives set the required levels.
- For EFOs, PIs specify key environmental flows at nodes, and objectives define acceptable levels of change to those flows.
Hydrological models are essential for calculating these indicators and assessing potential management changes.
Proposed updates to reporting nodes
Under the current water plan, there are 8 nodes across the water plan area. The draft plan updates the reporting nodes to make them more accurate and relevant. New locations are proposed to better reflect stream conditions:
- The Little Nerang Dam inflows node will be replaced with an outflow node. This change will help monitor flow releases, which are critical for aquatic species migration and downstream water quality.
- All end-of-system nodes will be retained as they are influenced by water management and provide important biological data.
- A new end-of-system node on Pimpama River is included for improved flow monitoring, as well as 3 new nodes on Back Creek, Tallebudgera Creek, and Currumbin Creek.
- Coomera River at Army Camp and Nerang River at Numinbah gauge stations are retained as these areas have significant water resource development.
- Mudgeeraba Creek node will remain as it is a complex system with no clear end-of-system.
These updates aim to improve how stream conditions are monitored and managed.
They also align with recommendations from the Department of the Environment, Tourism, Science and Innovation's Environmental Assessment Report - Water plan (Gold Coast) 2006, which highlighted the need to reconfigure nodes or reword outcomes for better assessment.
Hydrological assessments
Hydrological assessments play a key role in water planning, using mathematical models to simulate water infrastructure, usage, and how water moves through surface and underground systems. These models:
- help with decision-making by providing clear data
- generate measurable data to assess WASOs and EFOs
- help evaluate the impacts of authorised activities (e.g. taking or interfering with water).
Supplemented water management
For supplemented water, the draft plan maintains existing arrangements within the Nerang Water Supply Scheme (WSS), supported by infrastructure like Hinze Dam and Little Nerang Dam. Key points include:
- Allocations: supplemented water allocations will remain consistent with current entitlements and operational rules,
- Flow objectives: updated EFOs and WASOs will ensure ecological health and security of downstream water needs.
- Statutory releases: operational dam releases will continue with updated environmental management rules reflecting these obligations.
These changes provide certainty for urban and agricultural water users while supporting environmental requirements.