Ray Moulds, Sales Director at Flood Control International, takes a look at how automated sliding floodgates are supporting secondary containment at water and sewerage company sites.

Ray Moulds: As UK water companies continue progressing Industrial Emissions Directive (IED) improvement programmes, secondary containment is becoming a larger part of capital project discussions.

While the requirement itself is not brand new, the practical challenge often lies in implementing containment measures without affecting normal operation of treatment sites.

For sites with above ground sludge storage, containment systems frequently need to retain significant spill volumes while still allowing vehicle movements for tankers, maintenance access and day-to-day operational activities. Fixed containment arrangements can be difficult to integrate where access routes need to remain open under normal conditions.

Automated sliding floodgates are increasingly being considered as a ‘go to’ option for addressing this issue, particularly where containment boundaries and operational access requirements need to work together.

The IED secondary containment imperative

The Industrial Emissions Directive adopts an integrated approach to controlling emissions to air, water and land. Sewage sludge treatment facilities operated by water and sewerage companies fall within its scope through the Waste Treatment BAT Conclusions.

Containment strategies are commonly developed using CIRIA C736 methodologies. In many applications this results in secondary containment sized to retain 110% of the largest tank volume.

The challenge, however, extends beyond containment volume. Vehicle access routes frequently pass through containment perimeters, creating a need for systems that can maintain site operation while still performing during an incident scenario.

Why automation matters

Where secondary containment perimeters must accommodate vehicular access, the sliding floodgate represents one of the most practical engineering solutions available. Unlike fixed bund walls, stepped ramps or manual/semi-automatic gates, a sliding gate can be engineered to operate and close fully on a level threshold, permitting unrestricted vehicle and pedestrian access when open, while providing a fully sealed containment barrier when closed, without the need for manual latching.

The operational advantages of automation are significant. In a spill or emergency scenario, response times matter enormously. A gate triggered by a sensor — whether a level detector, a process alarm, or a building management system signal — closes without any dependence on human intervention. This is especially critical at unmanned or partially manned sites, which are common in the water industry's distributed asset base.

Flood Control International: a custom engineering approach

No two IED containment schemes are identical: existing civils, tanker turning circles, site layouts, access widths and control philosophies all vary. Early engagement between suppliers, civil, mechanical and operational teams can help identify issues and constraints before a spade is put in the ground.

Key technical features of Flood Control International’s (FCI) automated sliding floodgates include:

• Individual engineering design for each installation, to client specification
• Protection heights up to 2.8 metres and spans up to 12 metres, accommodate the largest site access openings
• Low-resistance rolling operation with positive seal compression on closure
• Level threshold design, eliminating trip hazards and permitting unrestricted tanker and pedestrian access
• Full automation of closure, locking and status monitoring, with integration capability to BMS and site alarm systems
• Trigger options including water level sensors, process alarms and push-button operation
• Remote status feedback confirming gate position — open, closed or fault — for control room visibility and permit evidence
•  Robust construction suited to the challenging chemical and atmospheric environments typical of sludge treatment centres
• Able to be retrofitted to existing concrete openings (no need for embedded parts)

Compliance across WIMES

Automated floodgate installations extend beyond the gate structure itself and typically incorporate associated steelwork, motors, instrumentation, electrical installations and control systems.

Corrosion protection remains an important consideration for wastewater applications due to hydrogen sulphide exposure and challenging environmental conditions.

Electrical installation arrangements, instrumentation requirements and health and safety provisions all influence final implementation.

Tailored to a company's asset standards

The UK water industry does not operate to a single uniform standard. Each WaSC brings its own asset management philosophy, engineering preferences and operational requirements to bear on procurement. FCI's engagement model is designed precisely to accommodate this complexity rather than presenting a standard product datasheet and asking clients to adapt their requirements to suit.

As water companies continue to progress their IED permit improvement conditions — many of which are now reaching the implementation phases agreed with the Environment Agency — the need for suppliers who can demonstrate this level of technical flexibility and regulatory understanding has never been greater. In a recent discussion, one engineering team identified automated sliding gates as a means of revisiting containment concepts that had previously been discounted because of access constraints

From design to delivery: the FCI service

FCI can support projects through design and site survey, gate sizing, manufacture, installation and commissioning, and ongoing technical support. For water industry clients managing complex capital programmes across multiple sites, this end-to-end capability significantly reduces the contractor coordination burden and the associated programme risk.

Commissioning activities can include verification of gate operation, automation functionality and control system integration.

The right gate for a regulated industry

As IED programmes continue to progress, secondary containment is increasingly becoming part of broader environmental risk management strategies.

Where unrestricted access through containment boundaries is required, automated sliding floodgates provide a practical solution. Suitability ultimately depends on site-specific requirements including space constraints, operational needs and maintenance considerations.

By developing systems around individual site conditions and asset requirements, containment measures can be integrated without compromising day-to-day operation.

For more information contact Flood Control International at This e-mail address is being protected from spambots. You need JavaScript enabled to view it or visit floodcontrolinternational.com