Accounting for water-related ecosystem services to provide information for water policy and management: An Australian case study

• Accounting for ecosystem services can provide information for water policy and management. • Models estimating water-related ES are in broad agreement but need more data to improve accuracy. • Water ES related to management issues of water scarcity, water quality and soil erosion were estimated. • The water ES accounts provide information for integrated water resource management (IWRM) • The accounts demonstrate the economy’s dependence on water ES and the ecosystems that supply ES. Effective water policy requires good information. The System of Environment-Economic Accounting Ecosystem Accounting (SEEA-EA) organises information on ecosystems and the interactions with the economy. We investigate how accounting for water-related ecosystem services (ES) using SEEA-EA could provide information for water policy and management, using the integrated water resource management (IWRM) framework and a case study from the Australian Capital Territory (ACT). A policy review and consulting process linking ACT water policies to SEEA-EA identified three key issues, water security, water quality, and soil erosion, which are evident in many parts of the world. Available data and models were used to account for three ES related to these issues: water supply, soil and sediment retention (soil erosion control), and water purification (nutrient retention). Modelled estimates varied but were broadly consistent and used to construct ES accounts. The accounts provide comprehensive information linking the ecosystems supplying ES to the use of ES in economic production and consumption. This supports five ACT water policy actions and three of the four IWRM Principles. The accounts suggest investment in catchment restoration and management in the Queanbeyan River Catchment to increase ES and improve water supply and quality. The accounts show how much of water is available (IWRM Principle 1), and recognise water as an economic good (IWRM Principle 4) by identifying the uses of water by industry and households. The accounting also enables a participatory approach to water development and management (IWRM Principle 2) by providing stakeholders with information for informed decision-making. Because the policy issues in the case study are common, and IWRM is widely adopted, there is potential to use SEEA-EA for water policy and management globally.