Freshwater is a vitally important global resource. As a result of increasing demand, water scarcity is increasing, leading to regional ‘water stress’. The source of freshwater, the local conditions, and the intensity of extraction determine whether the utilisation of resources is detrimental to the natural environment and to humans. Global freshwater resource depletion is driven primarily by food production systems.4747Food and Agriculture Organization of the United Nations (FAO). (2022). The State of the World’s Land and Water Resources for Food and Agriculture 2021—Systems at a Breaking Point. Rome, Italy: FAO. https://doi.org/10.4060/cb9910en

Water use in aquaculture has direct impacts on the availability of water for other users and biological processes4848For the purpose of this Criterion, water use refers only to freshwater used as part of the culture (production) process in land-based aquaculture systems. It does not include water use in non-production activities., making it important that aquaculture operations in sensitive regions are aware of their water use and act to improve the water efficiency of their farming processes.

This Criterion focuses on ASC-certified farms appropriately monitoring and using water responsibly.

Intent – The aquaculture industry conserves freshwater.

Farming activities, such as aquaculture, accumulate biological waste. Discharge and unregulated disposal of biosolids into the environment can cause negative impacts, including eutrophication, salinisation, spreading of disease and residues, and sedimentation of aquatic habitats.

Biosolids or sludge from aquaculture are often nutrient-rich and can be re-used, for example for fertilisation, if treated appropriately.4646Campanati, C., Willer, D., Schubert, J., Aldridge, D.C. (2021) Sustainable Intensification of Aquaculture through Nutrient Recycling and Circular Econoies: More Fish, Less Waste, Blue Growth. Review in Fisheries Science & Aquaculture (30) 143-169. https://doi.org/10.1080/23308249.2021.1897520 This provides an opportunity for the industry to contribute to building more circular economies.

This Criterion focuses on the on-site containment of biosolids by ASC-certified farms and potential for their re-use.

Intent – The aquaculture industry contributes to the circular economy by improving biosolids management.

Scope – Land-based sites.

Salinisation occurs when salt concentration rises in soil or freshwater, either naturally or due to human activities. It affects agricultural land, contributing to crop failures and reduces yields. It also affects local ecosystems, leading to habitat loss and biodiversity decline. With a growing global population, addressing salinisation is crucial for food security.4343Kumar, P., & Sharma, P. K. (2020). Soil salinity and food security in India. Frontiers in sustainable food systems, 4, 533781.

Aquaculture activities can cause salinisation through seepage from saline waterbodies, saline water discharge into freshwater, the intrusion of saline water into groundwater or the dumping of biosolids.4444Rajarshi, M., & Santra, S. C. (2011). Influence of Brackish water aquaculture on soil salinisation. Int J Res Chem Environ, 1, 60-65. In coastal regions, the effects of the dumping of biosolids can be amplified by rising sea-levels and land subsidence as a result of climate change.

This Criterion focuses on ASC-certified farms implementing best practices, such as pond liners, and regulating discharge of saline water to minimise contribution towards salinisation of soil and freshwater.

Intent – The aquaculture industry does not contribute to salinisation of soil or freshwater.