Stormwater Attenuation Tanks

We understand that the installation of a wastewater system is a big investment. But, with us you’re guaranteed a tailored service unique to you and your needs. Being experts in Sewage Treatment & Septic Tank Installations, we’re confident we can provide a solution that will last!

The intelligent storm water attenuation solution

Use our attenuation tanks to collect water from the roof and surface water and store it securely. Our tanks are watertight so you needn’t worry about them leaking! When it comes to inspection of the water tank, we provide access that’s safe, allowing space for safety ladders. Our Stormwater attenuation tanks are easy to maintain, if you want your tank to last, you’ll need to ensure maintenance is carried out regularly to have silt removed.

Additionally, our attenuation tanks prevent flooding occurring downstream, this is because the water is controlled and released slowly via a pumping chamber. So, if you’re looking to accommodate for increased rainfall.


Includes multiple inlets

We can value engineer a bespoke single piece system that encompasses multiple inlets, reducing the need for separate concrete manholes.

Flow control compartment

Bespoke single piece system that includes a flow control compartment, eliminating the need for a separate flow control chamber, alongside simplifying the whole installation process.

Complete void design

The complete void design facilitates silt removal which is almost impossible in a crated system.

120 years design life

We can specify a design life of 120 years in non aggressive and aggressive soils

Safe & easy access

We can incorporate access shafts and safety ladders for periodic inspection and maintenance such as silt removal, ensuring a more pleasant and safe experience.

Bespoke system

We can create a bespoke single piece system to to engineer your way around situations that would be difficult with traditional methods.

Installation service

If you need someone you can trust to install your system, then look no further.

We’re one of the UK’s leading specialists and can design and install a stormwater attenuation solution to meet your specific needs and budget. Trading for almost 30 years, we’ve built up a reputation for our excellent service, dedicated team and expertise.

Custom built to suit your needs

If you need a bespoke and cost effective solution to control the flow of water back to a water course or drainage system, look no further. Our stormwater attenuation systems aren’t limited in size or shape, unlike concrete or cellular systems, and can be designed to meet the specific needs of your design brief.

Questions & Enquiries

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We’re not your typical merchant. Core to everything we do is our customers. After all, without you, we wouldn’t be here. At Cotterill Civils, we offer something a little different and we show this in the values we adhere to every day! Why not get in touch today to see how we can help you!

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