09 December, 2025
Industries
Client
Department of Local Government Water and Volunteers
Disciplines
The South East Queensland agriculture sector is characterised by intensive, high-value horticulture and intensive animal production, with the industry subject to a range of pressures including urban encroachment and access to reliable water supplies. Synergies was engaged by the Department of Local Government Water and Volunteers to undertake the service need assessment for the SEQ Agriculture RWA, in addition to assessing the economic and financial feasibility of the shortlisted options. The service need assessment included extensive consultation with producers throughout SEQ to inform the development of a 30-year probabilistic water demand model.
The SEQ Agriculture RWA is a project designed to identify options to increase water availability and reliability for agricultural producers in SEQ. The structure of the SEQ agriculture sector differs to the rest of Queensland, with land use constraints, climate pressures, water constraints, and the proximity to major markets meaning agricultural production is heavily concentrated in high-value horticulture and intensive animal production, in particular poultry.
Key production areas include the major strawberry and pineapple growing areas in the Glasshouse Mountains-Sunshine Coast region, fresh vegetable and poultry production in the Warrill Valley region, and extensive fresh vegetable and other horticulture production in the Lockyer Valley and Somerset regions. Unlike other regions, agricultural water use in SEQ is primarily sourced from unsupplemented supplies, and there is often limited data and information available in relation to water availability and utilisation. The majority of agricultural production in SEQ is supplied into the domestic market. The seasonal horticulture producing regions typically benefit from being counter-seasonal to major growing regions in the southern states, meaning growers often access higher market prices during periods of limited supply from alternative growing regions. Production for export markets tends to be relatively sporadic, partially due to the uncertainty attributable to reliability of supply issues caused by climatic variability.
Synergies was firstly engaged to undertake the service need assessment for the RWA. As with the other RWAs undertaken by the Department, this involved the development of a comprehensive probabilistic demand model, informed by consultation with key growers and industry stakeholders and desktop research and analysis. A water supply-demand assessment was undertaken to inform the Investment Logic Mapping workshop undertaken at the conclusion of the first phase of the RWA.
The outcomes from the Service Need Assessment and ILM workshop informed the identification of a shortlist of infrastructure and non-infrastructure options to meet unmet agricultural water demand in SEQ over the 30-year outlook period. Synergies’ roles in the options analysis was to undertake detailed economic and financial analysis for each shortlisted option. This included modelling the regional economic impacts attributable to each option in terms of construction impacts and increased production value.
A probabilistic model was developed to derive 30-year agricultural water demand projections for SEQ. In addition to developing forecasts for region-wide agricultural water demand, water demands by commodity type were modelled at the sub-regional level, informed by desktop research and analysis of publicly available market data and data and information obtained through consultation with key stakeholders, including major growers.
The probabilistic approach provides an appropriate framework for incorporating uncertainty regarding key demand drivers, with the model producing a range of demand forecasts to inform the identification of service needs and analysis of options.
The key commodities included in the probabilistic modelling were the key vegetable crops grown in the Lockyer Valley and Scenic Rim regions (i.e. lettuces, carrots, onions, cabbages), pineapples, strawberries, turf, and poultry. The majority of the model parameters related to domestic market drivers and on-farm parameters such as crop yield and irrigation requirements, noting exports account for a relatively small proportion of demand for water-intensive agricultural commodities produced in SEQ.
Probabilistic water demand estimates were then produced over a 30-year outlook period. This was completed utilising the Monte Carlo simulation technique, with 5,000 scenarios modelled. Outputs were presented in P10, ‘Most Likely’ and P90 terms. This essentially provides a range of possible demands, noting the ‘most likely’ profile represents the demand profile derived by the model based on the central estimates across all demand model parameters.
As noted above, the model enabled characterisation of demands into sub-regional demands, based on spatial analysis of current production and stakeholder input on future demand growth.
Subsequent to the completion of the Service Need Assessment, Synergies was also subsequently engaged to undertake the economic and financial analysis of the shortlisted options in Stage 2 of the RWA. This included undertaking robust cost-benefit analysis to assess the economic feasibility of shortlisted options, and financial modelling to estimate the net cost to government for each option. Synergies’ non-linear input-output model was also applied to assess the economic impacts of the shortlisted options on the regional and Queensland economies, particularly in terms of the employment impacts from increased agricultural production.
Our approach to developing long-term agricultural water demand forecasts for the SEQ region provided the Department with robust, sub-regional forecasts of agricultural water demand across the region.
These demand profiles directly informed the identification of priority service needs in the Investment Logic Mapping workshop and the shortlisting of infrastructure and non-infrastructure water supply options for analysis in Phase 2 of the RWA. The probabilistic framework adopted to model the long-term demands also provided the Department with a meaningful range in terms of the growth outlook for various agricultural commodities.
Synergies’ robust economic and financial analysis of the shortlisted options was incorporated into the Opportunities Assessment Report for the SEQ Agriculture RWA, which was released for public consultation in October 2025.
To find out more about this project and how Synergies can assist you, send an email to: contactus@synergies.com.au