Drainage Systems

Certified surface and sub-surface drainage solutions for construction projects across Devon and the South West.

Expert Drainage Installation for Safe, Sustainable Sites

A well-designed drainage system is essential for managing water safely and preventing future site issues.

At JMJ Groundworks, we specialise in the installation of high-performance drainage systems that meet Building Regulation Part H and support long-term site resilience. Whether managing groundwater below a new build or surface runoff on a commercial yard, we provide fully certified solutions across Exeter and Devon that are built to last.

Why Choose JMJ for Drainage Works?

Our drainage packages combine technical expertise, quality materials, and precise execution.

Technical Expertise
We assess soil reports, water tables, and CAD drainage layouts to ensure precise gradients, flow rates and chamber locations.

High-Quality Materials
WRAS-approved pipework, chambers and geotextiles sourced from trusted suppliers, all backed by manufacturer warranties.

Advanced Plant & Testing
Our team uses GPS-guided trenchers, laser-levels and on-site compaction testing. CCTV footage and test certificates are included as standard.

QHSE-Driven Approach
Every installation follows a full Health & Safety plan, with risk assessments and environmental controls like silt fences and wash-down areas.

Case Study

Land Drainage Installation in Truro

New perforated land drainage installed to the correct falls

At an allotment site in Truro, we replaced an underperforming drainage system with a properly engineered one. Our team installed new 150mm perforated land drainage, correctly bedded and laid to the right falls, and cleared and rectified the connected manholes so the whole system drained freely. Every material was lifted in over the site’s surrounding walls by HIAB, and the finished system resolved the waterlogging that had affected the site.

What we offer

We design and install both sub-surface and surface water drainage systems to suit your site conditions and project scope.

Sub-Surface Drainage

Perforated Land Drains (French Drains)
Gravel-filled trenches containing perforated pipework to disperse groundwater away from structures.

Soakaways & Attenuation Systems
Crate or void-based systems that store and slowly release rainwater into the ground, preventing surface flooding and sewer overload.

Surface Water Drainage

Channel & Trench Drains
Surface-level linear drains with grates, ideal for collecting runoff in driveways, yards and loading bays.

Gullies & Inspection Chambers
Installed at low points to collect water and allow for easy maintenance and CCTV access.

Combined Sewer Connections & SUDS

We liaise with local authorities to carry out foul and storm sewer connections and install Sustainable Drainage Systems (SUDS) where required. Options include:

Swales
Permeable paving
Rainwater harvesting
Green infrastructure integration

Trusted Across the South West

Read reviews from our valued clients.

    
 
 
       Posted on Google  
   
   lewis franklin 
 
 
 
 Trustindex verifies that the original source of the review is Google. We recently worked with JMJ Groundworks Ltd on the installation of a new wash bay at our premises, along with improvements to our car park, and we couldn’t be happier with the result.

From start to finish, the team were professional, reliable, and highly skilled. The quality of workmanship is outstanding and everything was completed to a very high standard, on time, and with great attention to detail. They were well organised on site, communicated clearly throughout the project, and were a pleasure to work with.

JMJ Groundworks delivered exactly what they promised, and the finished wash bay and car park have made a significant improvement to our operations and site appearance. It’s clear they take real pride in their work and run their business properly.

We would not hesitate to recommend JMJ Groundworks Ltd to anyone looking for a dependable and high quality groundworks contractor and we look forward to working with them again in the future.

Lewis
  
 
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   Chris Joyce 
 
 
 
 Trustindex verifies that the original source of the review is Google. Joe and the team at JMJ Groundworks are great to work with. Incredible work ethic and really high quality work. Couldn't recommend them enough.
  
 
      Posted on Google  
   
   Eva Neitzert 
 
 
 
 Trustindex verifies that the original source of the review is Google. Joe and his team were fantastic. They worked incredibly hard to provide us with a drainage solution. Communication was clear from the outset. The team was professional and courteous. Would highly recommend.
  
 
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   Joel Hayes 
 
 
 
 Trustindex verifies that the original source of the review is Google. Amazing service. Went above & beyond.
  
 
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   BARRY GEORGE 
 
 
 
 Trustindex verifies that the original source of the review is Google. Very professional from quote through to completion.
Very happy client.
  
 
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   Sandy Winskill 
 
 
 
 Trustindex verifies that the original source of the review is Google. Excellent service, very quick and professional, we would recommend JMJ Groundworks to anyone.
  
 
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   Alex Wilce 
 
 
 
 Trustindex verifies that the original source of the review is Google. Joe gave us 5 star service  from beginning  to the end of the project. He was very friendly, professional and informative and did a great job building our patio on an awkward  piece of land. I would highly recommend  him.
  
 
      Posted on Google  
   
   murchie69 
 
 
 
 Trustindex verifies that the original source of the review is Google. First time working with Joe and his team and hopefully won’t be the last. Very polite and approachable in dealing with a high profile client. Definitely recommend.
  
 
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   John Benson 
 
 
 
 Trustindex verifies that the original source of the review is Google. We recently employed JMJ to fix a blocked drain and to repair the blockwork around it. Joe came out, gave us a quote and then did the work. We were very impressed not only with the workmanship, which was excellent, but with his whole approach. He kept us informed all through the work, so that we understood what he was doing and why. We would have no hesitation in recommending him.
John Benson, Blair Atholl Management Co. Ltd  28/04/2023
  
 
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   David Harvey 
 
 
 
 Trustindex verifies that the original source of the review is Google. Just finished working on a demolition and remediation project along side JMJ, very professional, look forward to them being on site at the next project

Need groundworks in Exeter and Devon?

Whether you’re managing a multi-phase development or a one-off infrastructure upgrade, we’re ready to help.