Slurry lagoon lining around Coventry

The farms on the city's doorstep

The green belt around Coventry is still working farmland, with dairy, beef and mixed units scattered through it. Many sit within sight of new housing, and the watercourses that run past them, the Sowe and its brooks and the Avon to the south, flow straight through the city. A store that seeps on one of those holdings is close to people and water at the same time, which is why the lining has to be right.

We are a short drive from these farms, so a lagoon job can be fitted around milking, field work and the weather rather than the other way round.

Our nearest lagoon

A little north of here, at Bodymoor Heath, our team lined a 2,000m² slurry store for a farm using welded LLDPE, sandwiched by 300g/m² fleece above and below. The weather turned wet during the install, so the work was resequenced to keep it on programme, and the lining was checked across its whole area before handover. It is now in use for the farm's slurry.

Single liner or double

How many layers go in depends on the material and on the conditions your adviser or the permit sets. Cattle slurry in a modest store can often sit on one welded sheet over fleece. Digestate, or a store close to a sensitive brook, may justify two sheets with a drainage net sandwiched in between to carry anything leaking past the upper one to a point where it can be seen, plus a floating cover over the top.

We settle the build-up with you against the design before ordering, because the membrane is made to measure for the lagoon.

• 300gsm non-woven fleece over the formation
• HDPE or LLDPE, single or double-lined
• Leak-detection layer between liners where specified
• Inlet, pump-out and depth markers sealed through the sheet
• Floating cover option

What you prepare, and what you get back

Your earthworks contractor shapes the banks and base and cuts the anchor trenches. Before the membrane is delivered, we walk the banks with the drawings to make sure slopes and trench positions match what the liner was made for. Then the sheet goes down, the panels are welded together, each pipe through the liner gets its own seal, and a trial weld is made and logged on the day.

At the end you hold a QA pack listing materials, weld results and the as-built layout. That is the paperwork an inspector or insurer asks to see under storage rules such as SSAFO, and it stays on file at the farm.