Selwood

SelTank

Smart storage for smarter water management

SelTank is a modular, intelligent storm overflow solution designed to help water companies and contractors cut Combined Sewer Overflows (CSOs).

Engineered by Selwood’s experts, it adds capacity, prevents overflows, and adapts to storm surges and peak demand.

Its advanced PLC “brain” automates flow control, ensuring safe, gradual discharge. With remote access, real-time telemetry, and data reporting, operators stay in control.

Selwood’s end-to-end service covers site surveys, transport, installation, risk management, CAD design, and aftercare — delivering a seamless, stress-free solution.

Key features and benefits

Smart automation

A PLC-controlled system ensures seamless flow management, live data reporting, and 24/7 remote monitoring

Flexible & scalable

Available in 45m³ and 35m³ sizes, with a modular CHAS-compliant design for quick deployment and integration

Versatile applications

Ideal for storm overflow support, wastewater storage, industrial use, and emergency response

Regulatory compliance

Helps meet government targets to cut storm overflows and protect bathing waters and ecosystems

Reliable & durable

Built for temporary or long-term use, ensuring robust performance in any environment

"SelTank has proven to be a reliable, adaptable storage solution that adds real value to our storm overflow reduction work, both in terms of operational performance and the insight it provides."

Ian Deakin

Senior Storm Overflow Engineer, Southern Water

Why choose SelTank?

With tighter regulations, increased fines, and rising public expectations, everyone must take proactive steps to prevent storm overflows.

SelTank is a proven solution — helping operators meet compliance, reduce Combined Sewer Overflow (CSO) events, and avoid financial and reputational risks.

Aligned with The Storm Overflows Discharge Reduction Plan, SelTank minimises ecological impact, protects public health, and supports the goal of reducing overflow events to fewer than 10 per year by 2050. Its advanced spill management system also mitigates harmful pathogens near bathing waters, ensuring a cleaner, safer environment.

On site in the Isle of Wight

A SelTank case study

Selwood deployed SelTanks to help a local water authority to avoid storm overflow and protect the environment.

In order to capture overflow during adverse weather, two SelTanks were installed on site, each with the ability to store 80,000 litres of wastewater until the storm weather passes, and then slowly return it to the network.

Feedback from the telemetry enables the customer to identify system optimisations including quicker return flows, enhance system performance, and provide additional storage capacity.

Our SelTanks remain on site long term to ensure the facility can handle high flows while protecting the environment.

Get SelTanks on your site

Whether it’s planned works or emergency response, our team is on hand to deliver fast, reliable water storage solutions

Get in touch today