Mechanical Design Engineer

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:

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.

Our team of Social Infrastructure specialists revitalise homes and communities by carrying out a wide range of work, from retrofit to refurbishment, and maintenance.

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.

• 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 equipment selection.
• Ensure designs comply with water industry standards, specifications, and regulatory requirements.
• Support development of 3D models and BIM outputs (where applicable).

• 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 and participate in technical reviews.

• 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.
• Assist with site surveys, asset assessments, and feasibility studies.
• Review and approve vendor drawings and equipment documentation.

• Identify opportunities 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.

• Degree or HNC/HND in Mechanical Engineering or related discipline.
• Experience designing mechanical systems within the water, wastewater, utilities, or process industry.
• Proficiency with CAD software (Solid Works, 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.

• 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:

• Career development – from the moment you join, you’ll be supported to develop, grow your skill set and progress your career the way you want.
• Cultivate – access to our idea and innovation platform, empowering you to drive positive business change.
• Cycle to work scheme
• Discounts – access to our leisure and shopping discounts and rewards platform.
• Employee networks – opportunity to join our organisation wide employee networks such as our Veteran’s network, Women’s…