Company: United Infrastructure
Location: Langstone
Posted: April 11th, 2026
United Infrastructure is a dynamic and rapidly expanding business, focused on delivering critical infrastructure projects, across the utility and social infrastructure sectors.
Our team of highly skilled and hardworking specialists deliver innovative solutions to the complex challenges our clients face.
Our company is split into two business areas:
Utility Infrastructure –
Our team of Utility Infrastructure specialists design, build and maintain critical water, energy (gas), power and telecoms infrastructure, for the UK’s largest network owners and operators.
Social Infrastructure -
Our team of Social Infrastructure specialists revitalise homes and communities by carrying out a wide range of work, from retrofit to refurbishment, and maintenance.
Role Purpose
To design, develop, and deliver mechanical engineering solutions for water and wastewater treatment assets, pumping stations, pipework systems, and associated infrastructure. The Mechanical Design Engineer ensures designs are compliant with relevant standards, cost-effective, maintainable, and optimised for reliability and performance.
Mechanical Design & Engineering
Produce detailed mechanical designs for water and wastewater treatment systems, including pumping systems, process equipment layouts, pipework, valves, frameworks, pressure-rated systems, and rotating equipment.
Prepare engineering drawings, specifications, P&IDs, datasheets, and bill of materials.
Carry out design calculations including pump head calculations, flow/pressure sizing, structural loadings (basic), and equipmentselection.
Ensure designscomply withwater industry standards, specifications, and regulatory requirements.
Support development of 3D models and BIM outputs (where applicable).
Technical Governance & Compliance
Ensure all designs follow CDM regulations, HAZOP/HAZCON considerations, and safe-by-design principles.
Ensure compliance with company design standards and relevant regulations (e.g., WIMES, Pressure Equipment Regulations, BS/ISO standards).
Conduct design risk assessments andparticipatein technical reviews.
Project Support & Delivery
Work with project managers, civil/ICA/electrical engineers, and external suppliers during project scoping, design, procurement, installation, and commissioning.
Provide technical support during construction, including responding to RFIs and reviewing contractor submissions.
Assistwith site surveys, asset assessments, and feasibility studies.
Review and approve vendor drawings and equipment documentation.
Identifyopportunities for improved asset performance, reduced operational costs, and system optimisation.
Support standardisation of mechanical solutions across the business.
Keep up to date with industry advancements, materials, technologies, and sustainability best practices.
Essential Qualifications & Experience
Degree or HNC/HND in Mechanical Engineering or related discipline.
Experience designing mechanical systems within the water, wastewater, utilities, or process industry.
Proficiencywith CAD software (SolidWorks, AutoCAD).
Strong understanding of pumps, valves, pipework, hydraulic systems, and mechanical plant used in water treatment.
Ability to produce engineering calculations and technical documentation.
Experience working to industry standards and regulatory requirements
Desirable Qualifications
Chartered or working towards chartership (CEng/IEng) with IMechE or similar institution.
Experience with BIM (Revit, Plant 3D).
Knowledge of WIMES specifications, DWI standards, and water industry best practice.
CSCS / SHEA Water or other industry safety certifications.
Some of our benefits include: