Reports

This page contains information about North Queensland Water Infrastructure Authority commissioned reports, analysis, etc.

Note: All reports should be considered as for deliberative purposes only, and do not represent Australian Government policy.

Western Queensland Irrigation & Agriculture Scheme

The Western Queensland Irrigation & Agriculture Scheme (WQIAS) project was commissioned by the North Queensland Water Infrastructure Authority in June 2020 to review irrigation scheme development opportunities in Western Queensland, based on concepts identified by Dr J.J.C. Bradfield.

The WQIAS project was undertaken by consultants GHD, and involved detailed engineering and hydrological assessments of eight alternative routes for the capture and transfer of water resources from the Tully, Herbert and Burdekin River catchments to facilitate agriculture development opportunities around the upper Burdekin and Flinders River Basins.

In addition to the smaller geographic focus on the upper Burdekin and upper Flinders Rivers, the WQIAS assessment differs from other examinations (such as the 2020/2021 Bradfield Scheme Assessment undertaken by CSIRO for the National Water Grid Authority) by assessing the initial water availability component primarily within the context of existing water plans, entitlement holder and environmental flow obligations.

Key findings

The WQIAS study found that while all of the potential routes were technically feasible, they would likely be uneconomic if constructed, and require significant subsidies over the long term to remain viable.

The main limitation centres on the volume of water available for transfer and irrigation (which are dictated by Environmental Flow and Water Allocation Security Objectives), with the other being the substantial capital and ongoing operational costs.

Projected capital costs ranged from $9B to $23B, with an estimated lower bound water price of $2,100/ML/annum, compared with $60/ML for similar regional irrigated agriculture schemes. While the report noted significant challenges, the work also noted the viability of pursuing targeted regional growth opportunities (including irrigated agriculture), via appropriately scaled water infrastructure closer to source.

The project factsheet, summary, final report and its supporting documentation can be accessed via the following links:

Concept Level Review: Hells Gates Dam - Webb Lake Transfer

In mid 2019, the North Queensland Water Infrastructure Authority commissioned consultants GHD to undertake a concept review and cost estimate update of a previously analysed element of the proposed Bradfield Scheme involving the large scale diversion of water from the potential Hells Gates Dam on the upper Burdekin River, south to an assumed terminal storage in the immediate environs of Webb Lake. The purpose behind the desktop analysis was to provide insight into the possible creation of a large agricultural zone located at Webb Lake, utilising water impounded at the Hells Gates Dam.

Key findings of the GHD Report:

It is technically possible to divert significant volumes of water (up to 700,000 megalitres per year) to the Webb Lake area under gravity via a purpose built channel.
Estimated capital and operational expenditures vary significantly, based upon the desired irrigation area, and the capacity of the water transfer channel. Based on a likely maximum irrigation area of around 56,000 hectares, GHD estimate capital costs of $4.56 billion and operational costs around $53 million per year.
Based on the estimated sustainable yield of Hells Gates Dam, water transferred to Webb Lake would likely negatively impact the irrigation opportunity along the upper Burdekin River.

Click image for larger version

Figure—Hells Gates Dam/Webb Lake—Possible Route

The GHD Report acknowledges the high level nature of the analysis, with further detailed study required to provide robust, investment-ready costings and data.

Concept Level Review of Hells Gates Dam—Webb Lake Transfer PDF: 3.5 MB

Groundwater Assessment of the Glendalough Alluvial Aquifers

In late 2019, the North Queensland Water Infrastructure Authority commissioned Innovative Groundwater Solutions to undertake an independent evaluation of the sustainable extraction limits of the resource located under Glendalough Station, northwest of Hughenden Qld. The purpose of the assessment was to better understand the scale of water availability at Glendalough, and the potential to support the development of the geographically adjacent Hughenden Irrigation Project.

The evaluation, which was completed in May 2020, suggests a sustainable extraction in the range of 2,300 megalitres/year with high confidence, to 13,300 megalitres/year with low confidence. This large range depends on the relative abundance of deep, high permeability sands and gravels, which to date have only been found in certain parts of the testing zone.

The evaluation also suggests limited opportunity for the use of managed aquifer recharge systems, utilising water from the nearby Flinders River. The report suggests the maximum sustainable extraction limits of the Glendalough Aquifer could be boosted by between 400-500 megalitres/year.

Groundwater Assessment of the Glendalough Alluvial Aquifers - Summary PDF: 100 KB
Groundwater Assessment of the Glendalough Alluvial Aquifers - Detailed summary PDF: 2.7 MB
Groundwater Assessment of the Glendalough Alluvial Aquifers - Report PDF: 5.2 MB