Soakaway Installed For Upton School
Upton School had been battling persistent flooding and surface-water pooling across its playground and sports field throughout the winter months. To safeguard pupils, staff, and the school’s facilities, Elite Drains Limited was commissioned to design and install a robust soakaway system capable of handling heavy rainfall and alleviating waterlogging issues.
Initial Survey and Site Assessment
Before anything, our team spent a full day carrying out an exhaustive site survey and assessment to ensure we installed a correctly sized system meeting all building regulations and requirements:
- Visual Inspection: We walked the entire playground, sports pitches, and surrounding landscaped areas to identify low points, existing surface-water runoff patterns, and access constraints.
- Ground Investigation: Borehole samples were taken at proposed soakaway locations to assess soil composition and permeability. Our qualified team thoroughly assessed these samples to ensure the correct position for the soakaway installation was selected.
- Percolation Testing: In accordance with BRE Digest 365 and BS 6297, we carried out falling-head percolation tests at three test pits. Each pit was filled with water, and the drop in water level was recorded over time to calculate the infiltration rate (typically aiming for at least 1 x 10⁻⁶ m/s for a crate system).
- Hydraulic Calculations: Using the school’s roof and paved area catchment data, our engineers calculated the required attenuation volume. For Upton School, a 200-crate soakaway (each crate providing approximately 80 L of void storage) was chosen, giving a total storage capacity of 16 m³.
This comprehensive assessment ensured the soakaway would perform reliably under the worst winter conditions.
Still unsure what a soakaway is? Read our full guide on “what is a soakaway?“.
Design and Regulatory Compliance
Elite Drains design team prepared detailed drawings and calculations to satisfy the properties and customers requirements. We ensured the following regulatory compliance was adhered to:
- Building Regulations Part H (Drainage and Waste Disposal for public buildings)
- CIRIA SuDS Manual (C753)
- BS EN 752—external drainage systems standards
- BRE 365—soakaway design codes of practice
Key design features:
- Crate Layout: 10 rows of 20 interlocking plastic crates, laid out beneath existing turf and to correct depth.
- Distribution Pipework: 110 mm perforated pipe connecting the school’s downpipes to the soakaway inlet chamber.
- Inspection Chambers: Two rodding/access points to allow future inspection and maintenance.
- Geotextile Wrap: Non-woven membrane to prevent silt ingress into the crates.
Our design pack was submitted to the school’s Estates Manager and Local Authority Building Control, who granted approval prior to works commencing.
Excavation and Installation
Safety and Site Preparation
- Traffic Management: Temporary fencing and signage were installed around the excavation zone to keep and pupils or staff at a safe distance.
- Ground Protection: Heavy-duty matting protected existing grass and pedestrian routes during machine movements.
- Utility Surveys: Cable-locates confirmed that no buried services would be disturbed.
Excavation
- A mini-digger excavated the soakaway pit to the precise depth required (approximately 1.2 m below existing ground level), allowing for 200 mm of clean stone bedding beneath the crates.
- Excavated material was screened for reuse; unsuitable over-clay was removed off-site via our certified waste carriers.
Crate System Installation
- Stone Bedding: A 150–200 mm layer of Type 1 granular stone was compacted as a level base.
- Crate Placement: Crates were assembled according to manufacturer’s instructions and level-checked.
- Distribution Pipework: Perforated pipe was laid with a gradient of 1:200 into the inlet chamber.
- Backfill: Crates were enclosed in a 20 mm clean stone surround and wrapped in geotextile membrane.
- Inlet and Outlet Chambers: Installed with lockable covers for maintenance access.
Read our guide on the “soakaway installation process” for more details on installing soakaways.
Post-Installation Testing
Once installation was complete, we conducted:
- In-situ Infiltration Test: To verify that the system accepted water at the designed rate, a calibrated water flow was introduced via the inlet pipe and outflow was monitored.
- Chamber Inspection: Using a CCTV drain camera, we checked for blockages within the pipework and crates.
All results were logged in our “Commissioning Certificate,” demonstrating compliance with Building Regulations and SuDS guidance.
Site Reinstatement
With the soakaway fully operational, our team restored the site to its original condition:
- Topsoiling: Imported topsoil was laid to achieve a smooth, level surface.
- Grass: We replaced the top layer of grass that was carefully removed before excavating.
- Tarmac Repairs: Cracked and sunken tarmac around the school drive was cut out and relaid to match existing finishes.
- Final Inspection: A joint site walk-through with the school’s Facilities Manager ensured every element met the agreed specification.
Outcomes and Benefits
- Flood Mitigation: Since commissioning, Upton School has had zero surface-water pooling, even during heavy spring showers.
- Pupil Safety: Play areas remain dry and slip-free, reducing accident risks.
- Low Maintenance: The crate soakaway requires only annual chamber checks, minimising disruption.
- Regulatory Peace of Mind: Full documentary evidence ensures future building surveys and audits will note compliant SuDS infrastructure.
Soakaway Installation Experts
Elite Drains Limited employ a team of specialist soakaway installation experts. Soakaways, particularly commercial and larger soakaways require expert knowledge and understanding of relevant standards to ensure compliance. Having a specialist soakaway team allows Elite Drains to carry out all size soakaway installation with ease. If you think your soakaway has failed or you are suffering from water pooling, waterlogging or flooding, contact our team today for advice and guidance.
For more information on soakaways, visit our soakaway installation page.
