About CaSTCo
This project, funded by The Ofwat Innovation Fund, is underpinned by a cross-sector partnership that includes water companies, freshwater and environmental scientists, academic bodies, eNGOs, and national regulators.
The Catchment Systems Thinking Cooperative – CaSTCo – has been created to build the UK’s first national framework for monitoring.
Through innovative prototyping and collaboration, CaSTCo aims to test and build a national framework that better supports communities, decision-makers, scientists, and industry to be able to use citizen science data meaningfully.
Through a rigorous peer review process of protocols and approaches, CaSTCo is developing a robust, standardised approach to the capture and integration of citizen science monitoring information to support decision-making.
CaSTCo partners are working to develop nationally consistent monitoring approaches, optimising data quality, ease of use, safety and cost-effectiveness, enabling all of us to contribute to healthier rivers and more resilient catchments.
CaSTCo principles
Projects #PoweredByCaSTCo are working toward best practices in applying these principles.
We aim to close the gap between people, data, and decisions that affect rivers.
1. Collaborative
- Build a community aiming to improve river health
- Break down barriers between sectors, including volunteers
- Invest in collaborative plans and communicating outcomes
2. Impactful
- Collect data for a purpose or outcome
- Measure the results of new and existing approaches
- Invest in projects that multiply impact
3. Open
- Share data and ideas openly as a default
- Provide easily accessed resources and lessons learned
- Shine a spotlight on successes and how others can replicate them
4. Rigorous
- Use appropriate best practices to collect and share data
- Provide transparency on protocols to use results effectively
- Institute checks and reviews that ensure high-quality
5. Future-minded
- Grow our community’s capacity to take care of rivers for the long term
- Develop and use tools that support impact-driven outcomes
- Embrace flexibility, adaptivity and innovation when appropriate
Does this resonate with you?
We are developing an assessment process for best practices of these principles. If you believe your organisation or project abides by these principles, you can fill out this form to be included on our CaSTCo map.
A cooperative in action
CaSTCo recognises that without concerted and cooperative action at a national scale, a coherent and impactful environmental monitoring system will not appear.
The cooperative partners represent the varied actors across the water ecosystem. We regularly come together to collectively test and shape the components of the framework, share our insights, prototype tools and guidance, and strengthen relationships across the cooperative.
Our meetings have been held around the country so that we have been able to go into the field to see the work of our demonstrators in practice, which has led us to share new ideas. This exchange of knowledge, skills, and priorities is integral to creating the movement we need to build to change how we work together for better catchment outcomes.
Building an ecosystem of sharing
CaSTCo aims to strengthen the ecosystem of organisations working to improve catchment health.
As partners collaborate and learn about what’s happening in other regions, we’re sharing resources, knowledge and opportunities to support each other’s events, learning how to apply approaches within their areas, as well as building awareness of the work to monitor and improve catchment health and how this could be better joined-up. For example, the Ribble real-time blitz was an event organised by the Ribble Rivers Trust and attended and supported by the Environment Agency, Riverfly Partnership, United Utilities, Water Rangers, the Angling Trust and more.
By supporting each other, we’re providing richer experiences for our communities and avoiding duplicating efforts.
CaSTCo Taskforce
Over the course of 2025, the CaSTCo project has also convened a Taskforce to develop a national roadmap for collaborative catchment monitoring that builds on the work completed in demonstrator catchments. Structured in “Sprints”, 60+ participants across government, academic, industry, NGOs and community science have begun shaping how CaSTCo reshapes the landscape at the national scale.
Full outputs and recommendations documents will be available soon after those participating have had a chance to respond to them. Sprint 3, happening at the end of April 2025, will focus on quality assurance and operationalising our shared vision. Outputs will shape recommendations to the Cunliffe Review and DEFRA and the Roadmap will outline the pathway to national scale-up and policy integration.
Taskforce output highlight: Four core pillars
Emerging from Taskforce sprints 1 and 2, these guide not just what we do, but how we communicate the value, urgency, and long-term impact of this work.
They reflect the transformation we’re driving across the sector: from how data is gathered to how trust is built.
From fragmentation to integration
- Stakeholders called for a nationally standardised monitoring framework.
- Emphasis on creating a unified governance structure and shared data platforms.
- Need to clarify stakeholder roles and embed interoperability from the start.
From data collecting to decision-making
- A shift is needed from data accumulation to strategic insight.
- A ‘Weight of Evidence’ approach will support better-informed decisions across policy, regulation and enforcement.
- Call for investment in real-time sensors, AI, and accessible digital platforms.
From short-term fixes to long-term resilience
- Develop sustainable funding models blending public and private sources.
- Establish regional Citizen Science Hubs with robust validation protocols.
- Embed monitoring frameworks into long-term planning and regulation.
From public distrust to public engagement
- Recognise and empower citizen scientists as knowledge co-creators.
- Use open data, feedback loops, and clear storytelling to rebuild public trust.
- Wensum Catchment case study shows citizen science delivering regulatory value.
Project leads
The Rivers Trust
In its role as co-lead on the project, The Rivers Trust is bringing together all of those involved in CaSTCo to create a sustainable blueprint for more impactful working practices in the future. They provide technical expertise to the 9 demonstrator areas and wider partnership to shape CaSTCo’s framework and standards for a more collaborative and integrated approach to how we monitor, use data, and make decisions about our rivers. The Rivers Trust also leads The Big River Watch, a campaign to inspire people to reconnect with their local river and engage with citizen science
United Utilities
United Utilities is co-leading the CaSTCo project. Within the project itself, they’re developing a more integrated approach to catchment monitoring by working closely with Ribble and Mersey Rivers Trusts and developing a shared understanding of citizen science recruitment at scale and on-going engagement. By sharing learning and development experience through joint training of river rangers and Rivers Trust volunteers, they’re also exploring a process to prioritise sampling locations.
Partners and demonstrator catchments
Each of the demonstrator catchments had a theme for prototyping tools and approaches, as well as core partners that have acted as the foundation of collaboration to progress our collective understanding.
Anglian Demo
Water quality
Arun & Rother Demo
Soil health and regenerative agriculture
- Western Sussex Rivers Trust
- Southern Water
- Countryside and Community Research Institute, University of Gloucestershire
- Environment Agency
Case study coming soon
Beane Demo
Chalk streams
- Herts and Middlesex Wildlife Trust
- River Beane Restoration Association
- Affinity Water
- Environment Agency
Case study coming soon
Northwest Demo
Fish, water quality
- Ribble Rivers Trust
- Mersey Rivers Trust
- United Utilities
- Environment Agency
Case study coming soon
Tamar Demo
Diffuse water quality
- Westcountry Rivers Trust
- University of Exeter
- South West Water
- Environment Agency
Case study coming soon
Thames, London
Tackling urban pollution
- Thames21
- Thames Water
- Zoological Society of London
- Environment Agency
Usk Demo
Agriculture and catchment health
- Wye & Usk Foundation
- Dwr Cymru
- Cardiff University
- Natural Resources Wales
- Environment Agency
- Gwent Wildlife Trust
National partners
Providing guidance and support: Riverfly Partnership, Freshwater Biological Association, Earthwatch Europe, UK Centre for Ecology and Hydrology, River Restoration Centre, Zoological Society of London, Cartographer, The Rivers Trust, Water Rangers, and many more.