CIRIA has been developing a supplement to its widely used guidance C736: Containment Systems for the Prevention of Water Pollution (2014), reflecting growing industry demand for updated best practice.
As regulatory expectations continue to evolve, this update is expected to address how containment systems perform under modern conditions — including new risks, materials, and technologies.
Why CIRIA C736 Still Matters
Since its release in 2014, CIRIA C736 has become a key reference point for pollution containment design, used by:
- Drainage engineers and consultants
- Environmental regulators
- Industrial site operators
- Infrastructure and utilities projects
Regulators increasingly expect sites to demonstrate compliance with its principles — particularly around:
- System reliability
- Containment capacity
- Risk-based design
Why an Update Is Needed
While C736 remains highly relevant, industry experience over the past decade has highlighted several gaps.
According to CIRIA’s consultation process, key areas for the supplement include:
- Application of risk-based design approaches
- Advances in materials and containment technologies
- Improved methods for testing structural integrity
- Real-world case studies and lessons learned
- Emerging site scenarios and infrastructure challenges
What This Means in Practice
For site operators and designers, the update signals a clear direction:
Containment systems must be more reliable, more responsive, and better aligned to real-world conditions.
This is particularly important where sites face:
- Firewater runoff risks
- Chemical storage and handling
- Surface water discharge to controlled waters
- Increasing regulatory scrutiny
The Shift Toward Performance-Based Containment
One of the most important themes emerging from industry feedback is the need to move beyond static or manually operated systems.
Modern guidance is increasingly aligned with systems that can:
- Respond automatically during an incident
- Operate independently of human intervention
- Provide measurable, auditable performance
- Function under emergency conditions, including power loss
This reflects a broader shift toward performance-based containment, rather than simply specifying components.
Aligning with Emerging Best Practice
While the CIRIA supplement will formalise updated guidance, many of these principles are already being adopted across industry.
For example, automated containment systems such as ToggleBlok® are designed to:
- Isolate drainage networks within seconds of a trigger event
- Integrate with fire alarms, environmental sensors, and monitoring systems
- Operate as stand-alone units during power or system failure
- Provide real-time status and reporting
This type of approach aligns closely with the direction of travel in both guidance and regulatory expectations.
Looking Ahead
The CIRIA C736 supplement is expected to provide valuable clarity for engineers, consultants, and site operators — helping ensure containment strategies reflect modern risks and technologies.
However, the key message is already clear:
Containment design must evolve alongside the risks it is intended to manage.
Waiting for formal updates before reviewing existing systems may leave sites exposed in the meantime.
Reviewing Your Current Approach
For organisations relying on existing containment infrastructure, now is a good time to assess whether systems remain fit for purpose.
Consider:
- Does your system respond automatically or rely on manual intervention?
- Can it perform reliably under emergency conditions?
- Is it aligned with current CIRIA guidance principles?
- Would it meet increasing regulatory expectations?
Staying Ahead of the Guidance
At Sandfield Penstock Solutions, we work with engineers and operators to develop containment strategies that align with both current and emerging best practice.
As guidance evolves, the focus remains the same — ensuring that containment systems perform when they are needed most.
Need help implementing CIRIA C736?
Containment strategies should always be developed based on site-specific risk, drainage layout, and operational requirements.
Our team supports engineers and consultants in applying CIRIA guidance to real-world projects.
