Workplace type: On-site (with UK travel)
Salary range: £46,000 – £50,000 per annum + company car + private healthcare scheme + gym
About the role
Are you a water treatment engineer who wants to see your designs make a real difference on some of the UK’s biggest construction and infrastructure projects? As our Water Treatment Process Engineer, you will be WJ’s hands‑on technical specialist for water treatment: designing, specifying and commissioning the systems that turn challenging site water into compliant discharge. Based at our Plant Yard/Office in Bilsthorpe, Nottinghamshire, and reporting to the Assistant Operations Manager, you will work across construction discharge treatment (fines/suspended solids and pH correction), contaminated groundwater and surface water, and industrial/process water, and help us develop new capabilities in tunnelling TBM treatment (including treatment dewatering) and bentonite treatment.
What you'll do
- Design treatment solutions for fines/suspended solids and pH correction, contaminated groundwater and surface water (e.g. hydrocarbons, metals, ammonia), and industrial/process water.
- Prepare process designs, treatability assessments, mass balances, process flow diagrams and equipment specifications.
- Interpret water quality data and laboratory results to build discharge compliance strategies that meet consent and permit requirements, working with clients consenting teams, the Environment Agency, other regulators.
- Lead the commissioning and performance‑proving of treatment plant on site, then optimise and troubleshoot systems through operation.
- Help shape WJ’s treatment fleet, chemical dosing and equipment specifications, and develop new treatment capabilities.
- Provide technical input to bids and tenders, and support our Business Development and Technical Sales teams with client presentations and site visits.
What you'll bring
- A degree in chemistry, chemical/process engineering, environmental engineering, civil engineering or a related discipline.
- Proven experience in the process design and commissioning of water treatment plant and systems.
- Hands‑on experience delivering treatment on live sites, including plant operation, optimisation and troubleshooting.
- Experience treating construction discharge water and/or contaminated groundwater or surface water.
- Working knowledge of discharge consents, environmental permitting and water quality compliance.
- Ability to interpret water quality data and prepare clear technical reports.
- Good communication skills, with the ability to explain technical solutions to clients and
- colleagues.
- A full UK driving licence.
- Desirable: TBM, sludge dewatering or bentonite treatment experience; chemical dosing, coagulation/flocculation, clarification, filtration or adsorption systems; chartership (or working towards it) with CIWEM, IChemE or similar, SMSTS/SSSTS site qualifications.
This is an opportunity to become the go-to technical expert for water treatment in a business that is investing in its treatment capability. You will take your designs from concept through to commissioning, work alongside supportive engineering and operations teams, and help build new treatment capabilities for tunnelling and major infrastructure projects. In return, WJ offers a salary of £46,000 – £50,000 per annum, a company car, a private healthcare scheme, gym and investment in your professional development.
About WJ
WJ is the UK’s leading water management specialist the partner and contractor of choice for major construction and infrastructure programmes. Founded by academics and evolved through expertise, we apply scientific principles to solve complex water challenges: over 40 years’ experience and 4,000+ projects worldwide, including the Channel Tunnel Rail Link, the London Olympic Park, Crossrail, Tideway, HS2 and currently Sizewell C. Our expanding service lines span dewatering & groundwater control, water treatment, surface water management, I&M, pumping tests, well drilling and professional services which are grounded in engineering, delivered in partnership. Our values of Confidence, Pride, Clarity & Integrity, and Independence guide every decision we make, and our ambitions are big: the AMP8 water sector, defence, energy and infrastructure markets.
Water Treatment Process Engineer employer: WJ UK
WJ is an exceptional employer, offering a unique opportunity for the English Language Manager to lead and grow a dedicated Instrumentation & Monitoring division within a well-established engineering company. With a strong commitment to employee development, competitive remuneration, and comprehensive benefits including private healthcare and gym memberships, WJ fosters a supportive work culture that values innovation and collaboration. Located in Kings Langley, Hertfordshire, employees benefit from a vibrant community and the chance to work on significant infrastructure projects across the UK, making it a rewarding place to build a meaningful career.
