We value your privacy

Our website uses cookies to enhance your experience. By continuing to use our website, you are agreeing to our use of cookies. Necessary cookies are always enabled. You can read more about our Cookie Policy in our Privacy policy

We value your privacy

Cookies are small text files stored on your computer by websites you visit. They help users navigate websites efficiently and enable certain essential functions. Cookies necessary for the website to function properly can be set without your consent, while all other cookies require your approval before being used in your browser.

Additionally, we use cookies to gather data for personalizing and evaluating the effectiveness of our advertising. For more information, please refer to the Google Privacy Policy.

You can find the list of all the cookies that we use on our website here.

attenuation tanks

Attenuation tanks

Carpark case study

Discover how modern stormwater management solutions, such as attenuation tanks, can transform carpark drainage systems. This case study explores the installation of Tricel attenuation crates at a new 104-space carpark, showing how sustainable drainage design supports planning permission, compliance, and flood prevention.

Project Overview

As part of the design for Tricel’s new 104-space carpark, an underground attenuation system was installed to manage surface water runoff from the impermeable tarred parking surface. This sustainable solution was a key requirement in securing planning permission, aligning with Sustainable Drainage Systems (SuDS) regulations, which are standard for developments of this scale.

Without attenuation, local drains and watercourses could become overwhelmed during heavy rainfall, significantly increasing the risk of flooding on-site and in surrounding areas.

attenuation tanks

Solution

To address the high runoff volumes from the tarred carpark, the design adopted Tricel Rigofill ST-S crates (modular attenuation tanks) as the core of the system. These crates are part of Tricel’s storage/infiltration range and are well suited for trafficked areas.

Key attributes and how they were leveraged in this carpark project:

  • High Void Ratio (≈ 96 %)
    Rigofill crates provide an exceptionally high storage-to-solid volume ratio, enabling efficient water storage in a relatively compact footprint.

  • Modular & Flexible Design
    The crate blocks, typically in 800 × 800 mm dimensions (full and half blocks), allow tailored layouts to meet the volumetric demands of the site. The modularity also supports horizontal and vertical stacking, adapting to varying depths under the carpark.

  • Structural Strength & Traffic Load Capability
    Rigofill systems are engineered to withstand heavy traffic loads (SLW 60 / HGV 60), making them fully appropriate for use beneath a carpark surface.

  • Inspection & Maintenance Accessibility
    The crates include a cross-shaped internal inspection tunnel that allows full access via camera or flushing equipment in two axes, enabling detailed inspection of both the drainage surfaces and structural components.

  • Depth Capability
    For deeper installations, Rigofill crates support installations up to depths of 4 m (or more depending on block type), enabling the system to fit under the carpark subgrade without excessive excavation.

By using Rigofill ST-S crates, the design achieved both efficient attenuation and structural robustness, while maintaining the ability to inspect and maintain the system over its operational lifetime.

Stormwater attenuation tank

Installation Process

  1. Excavation & Preparation – The carpark sub-base was excavated and leveled to accommodate the attenuation system.
  2. Crate Installation – Modular attenuation crates were positioned and securely wrapped in a geotextile membrane.
  3. Drainage Integration – Inlet and outlet connections were made, including the overflow link to the local drainage network and the oil separator.
  4. Backfilling & Surface Restoration – The system was covered, compacted, and the carpark surface was reinstated for immediate use.

Conclusion

  • Flood Prevention: The system prevents stormwater from backing up and flooding the carpark or adjacent properties.
  • Environmental Compliance: Meets SuDS planning requirements and ensures sustainable, on-site disposal of surface water.
  • Pollution Control: The oil separator protects local watercourses from untreated pollutants.
  • Planning Approval: Installation of attenuation tanks was instrumental in obtaining planning consent for the development

This project demonstrates how attenuation tanks provide a sustainable, compliant, and practical solution for stormwater management in commercial developments. By combining large-capacity underground storage with pollution control and overflow safeguards, Tricel’s attenuation system ensures long-term resilience against flooding while protecting local environments.

Other articles you may be interested in

Key features

End to end solution icon

End to end solutions

Comprehensive systems that handles all phases of the process from start to finish

Certified icon

CERTIFIED

Complies with EN 17152-1

Quality icon

TECHNICAL EXPERTISE

Unrivalled technical expertise by our sales team regarding stormwater management solutions

If you have any questions or would like to discuss your project with us, don’t hesitate to get in touch. 

Get in touch

 

up
error: Content is protected !!