Waste Water

Our nationally recognised specialisms underpin our clients’ operations through the entire water lifecycle – including waste water from inlet works to primary through tertiary treatment to outfalls, our specialist skills go hand in hand with our more generalist capabilities to provide the most efficient solutions to construct, repair, maintain and protect your assets.

Stonbury’s Long-Term Commitment

At Stonbury, our industry-recognised specialisms underpin our clients’ operations through the entire water lifecycle – including waste water from primary to tertiary treatment.


This end-to-end capability is an especially long-term commitment, so we insist on directly employed, specialist teams who can deliver the most totex-efficient combination of solutions over time – across repair, refurbishment and maintenance, but also “construct new” civil engineering.

Stonbury’s waste water expertise serves over 50 million users of eleven UK water companies, including the eight largest.

View some of our waste water projects here

Digesters and Other Assets Our Proven Track Record

Digesters are at the heart not only of sewage and waste water treatment, but green biogas production, too.

This brings into play many critical structures – gas zones, pipework, storage – requiring the kind of specialist civils expertise most generalist subcontractors simply cannot provide.

Stonbury’s directly employed civil engineering teams have a proven track record of delivering repair, refurbishment and “construct new” projects for digester installations and associated assets, encompassing:

  • Green storage – Stonbury recently completed the construction of an entire anaerobic biogas digestion storage lagoon for Yorkshire Water
  • Heavy engineering – Including hydro demolition and steel fabrication
  • Maintenance and safety – Inspection, cleaning, installation of handrails, ladders and walkways
  • Repairs – To concrete, steel, and joints
  • Coating and waterproofing – Surface blasting and jetting, corrosion protection, re-lining
  • Pipework – Installation and replacement of pipework, valves and fittings

Stonbury manages project progress through innovative IT solutions and communications portals that it has developed for its clients, making even complex civil engineering projects collaborative and transparent from day one.


Waste Water Treatment Structures The Client’s Challenge

Not all tanks are created equal. Settlement tanks, storm tanks and aeration lanes are a very different proposition to chemical storage tanks – but no client wants to have to take on and manage two different sets of engineering contractors to deal with their refurbishment, maintenance and repair!

One team for all steel and concrete repair and maintenance

At Stonbury, we do things differently – which is why we achieved a score of 100% for Quality in the industry’s recent UVDB Verify review. Our directly employed teams have the experience, expertise and training within their ranks to manage all manner of tank refurbishment, repair and maintenance tasks, including:

  • Condition surveys – Internal and external, including photographic/video reports
  • Repairs – Concrete, resin, grouting, welding including PST wall tops
  • Joint sealing – from gun grade and pourable sealants to overbanding systems
  • Waterproofing  including membranes and coatings
  • Pipework – installation and alteration
  • Cleaning and chlorination – including in-house refurbishment offsite
  • Supply, fabrication, and installation  of tanks, vessels, access covers, ladders, walkways

And with all our managers NEBOSH-qualified, and all our supervisors SMTS-trained, our clients can be sure that we take industry-leading pride in how we operate, not simply in what we do.

Pipe and Other Bridges Accessibility for All Environments

Nature was not designed for easy access! Often, critical water infrastructure is in difficult locations, made worse by weather and environmental factors, so improving and refurbishing structures like bridges can be extremely problematic.

Generalist civil engineering subcontractors who have none of their own specialist equipment can be a risky and costly choice for this kind of work.

Stonbury’s directly employed civil engineering teams, on the other hand, work with our owned equipment to deliver totex-efficient combinations of repair, maintenance, refurbishment and “construct new” projects - without the costs and management overheads of subcontracting to disparate teams for each specialism.

Water asset access; protecting, improving, renewing

Stonbury’s proven expertise in working with almost half of all the UK’s water companies has delivered successful bridge projects for Affinity Water, Severn Trent Water, United Utilities, Welsh Water and more, encompassing:

  • Pipe bridges, impounding reservoir access bridges, foot bridges
  • Full encapsulation - For environmentally sensitive locations
  • Surface protection - Including blasting, jetting and coatings
  • Repairs – Including bespoke fabrication of new components and structures

Stonbury’s use of directly employed teams, enables us to train and upskill our workforce to deliver constantly outstanding service, in line with our industry-recognised accreditations (ISO 9001 Quality Management, ISO 14001 Environmental Management, OHSAS 18001 Health and Safety Management, and many more.)