Wastewater & Infrastructure
Sewage Treatment Plant Companies
STP providers covering packaged, modular, and large-scale sewage treatment for municipalities and compounds.
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96 results from 96 matched providers

Evergreen Water Solutions
A leading supplier of progressive wastewater treatment systems Evergreen Water Solutions works closely with a number of international engineering companies whose expertise are in scalable wastewater treatment systems and containerised wastewater treatment systems for municipal and industrial application. Evergreen Water Solutions offers a comprehensive engineering service. Our company incorporates initial design and planning, to implementation of projects that are delivered on time and on budget. Our expertise in wastewater treatment covers infrastructure development, package sewage treatment systems and advanced treatment technology for wastewater recycling with the strictest treatment requirements. The goal of Evergreen Water Solutions is to exceed the expectations of our clients, foster long-term relationships, and make a positive impact on the environment and industry standards. Evergreen Water Solutions use innovative products and suppliers to source, design and implement leading environmental water and wastewater treatment products and solutions. All new equipment and suppliers are required to undergo pre-qualification program and a series of acceptances and trials are applied prior to the approval of the vendor. Evergreen Water Solutions’ pre-qualification program guarantees you our clients that the products we source are of the highest standard within the industry, these products along with the expertise within Evergreen Water Solutions ensures that the solution we provide will meet and exceed any expectation you might have.

FP McCann Ltd
With sixteen divisions and twelve manufacturing plants, FP McCann is the UK’s largest precast concrete manufacture. They provide an extensive range of precast concrete solutions, including drainage, tanks, tunnels and shafts, rail, power and infrastructure, filter bed systems, walling, fencing, agricultural, architectural and structural building solutions, flooring, dock leveller pits and specialist precast products. McCann will customise their solutions to ensure they create maximum value for your project, accommodating your site conditions, design requirements and construction needs. The quality and reliability of McCann’s products and services are the foundation of their success. They are constantly developing and improving their solutions, whilst striving to exceed their customers’ expectations. McCann’s extensive range of precast drainage products include pipes, wide wall/manhole chambers/soakways, cover slabs, gullies, headwalls, box culverts, fall arrest systems, house inspection chambers, catchpits, flow control and valve chambers, hydrodynamic separators, rain harvesting systems etc. They also provide bespoke multipurpose tank chambers and panel systems. The geographical spread of their twelve modern precast manufacturing plants, coupled with their ability to deliver to their clients’ specifications on major projects across the UK and Ireland, has established McCann as a valuable and reliable partner. At McCann, they promise to build strong, sustainable relationships with their stakeholders. By implementing their corporate values, they aim to deliver on this guarantee through their products, services, communications and, above all, the behaviour of their people. They recognise the importance of operating with integrity and apply high standards of corporate governance in the conduct of their business.

FT Ductile Ltd
Ductile Iron Pipe and Fittings FT Ductile supplies a wide range of high quality, ductile iron pipes, fittings and ancillary products to the water industry for both potable and dirty water. Large stocks at our premises allow us to fulfil many orders on a next-day basis. Whatever the size of project, we can provide a tailor-made solution to include the sourcing, supply, delivery and after sales service. We supply ductile iron pipes in a range of diameters, from 80mm to 1600mm. Over the years, the range of products supplied by FT Ductile has expanded to include everything from ductile iron pipes to flange adaptors and valves. We have a number of exclusive distribution agreements in place and all products conform to DWI standards. Ductile iron pipes are most commonly used for drinking water and sewage distribution, usually lined with cement mortar in order to prevent corrosion over time. The benefit of using ductile iron pipes in potable and waste water systems is that they are stronger and resistant to fracture. FT Ductile has supply chain links with companies in Europe, USA and the Far East which has given us strong foundations for understanding how other cultures and nationalities like to do business. This information is invaluable when we come to export our pipe products and services. Wherever you are based, and whatever you require, from individual items such as valves and fittings, through to more complex orders for lengths of ductile pipe and fittings, we will provide you with our best possible price. And you can rest assured that through our extensive transport links, our products will reach you in a safe and timely manner. To find out more regarding our ductile iron pipes and other products, please feel free to contact us.

Gardner Denver Ltd – Robuschi
In a competitive and evolving global market, our long history of supplying aeration equipment in wastewater treatment plants that best meets customer specific requirements, makes Robuschi a trusted and reliable partner for the environmental industry. Cost-effective solutions for new plants or refurbishments of existing installations are a major focus of our product excellence and application expertise. Therefore, as a global supplier of environmental solutions, we lead the market in developing innovative technologies that support our customers in reducing life cycle costs, increasing efficiency, meeting legal requirements and, finally, improving the quality of product or services they want to provide to their own customers. In wastewater treatment plants, power consumption mainly comes from aeration machines. Robuschi supplies PD blowers and screw blowers, able to provide significant energy saving, depending on plant configuration. Additionally the Robox Energy combines the technological advantages of Robuschi screw compressor and permanent magnet motor with Smart Process Control tool to halve wastewater treatment plant running costs. Ecological sustainability is part of the Robuschi strategy, focusing on promoting environmentally friendly promoting, enhancing energy saving and protecting natural resources.

Hydro International
Hydro International, a CRH company, provides advanced products, services and expertise to help municipal, industrial and construction customers to improve their water management processes, increase operational performance and reduce environmental impact. Hydro International can help water companies meet their AMP and environmental obligations, including the reduction of sewer overflows and the Water Industry National Environment Programme (WINEP). Hydro International provides total solutions for Inlet Works, Combined Sewer Overflows (CSOs), Stormwater Management, Flood Warning and Prevention, and Water Resource management, from design to supply and installation through to ongoing preventative maintenance, servicing and emergency repair. These solutions include: Hydrometric data collection, monitoring analysis and reporting for river level, reservoir, network and weather. Continuous water quality monitoring for compliance with Section 82 of the Environment Act. Water resource analysis and consultancy. Stormwater management solutions, including options for Sustainable Drainage Systems. (SuDS) and Smart Maintenance. CSO event duration monitoring. CSO and storm tank treatment and screening. Passive flow controls for flood prevention schemes, SuDS, CSOs and WwTWs. Inlet works screening and grit removal solutions. Sludge screening. Dropping sewage or water safely from height. Hire, repair and maintenance of inlet works screens and screenings handling equipment

Kent Stainless Ltd
Solids Technology International was established in 1979 in Dublin, Ireland to develop high-performance belt filter dewatering equipment and innovative solutions for the water and wastewater industry. In 2002 the company was taken over by Kent Stainless. The manufacturing facility includes 3D laser cutting, CNC sheet, electro-polishing and bead blasting finishing plants. Employing over 100 people and resources including over 50 people with mechanical or electrical trades and over 20 design engineers working utilising 3D design packages gives Solids Technology the capability to supply turnkey thickening, dewatering and poly preparation solutions. Today there are over 800 Solids Technology belt filter systems worldwide and are one of the leaders within the marketplace for Stainless steel, fully enclosed, automated high-performance dewatering and thickening system. Our product range includes: Filter Belt Presses, Gravity Belt Thickeners, Poly Preparation Systems.

KGN Pillinger
Advanced Pumping & Engineering Solutions With a heritage dating back to 1926, KGN Pillinger is a trusted partner in engineering and manufacturing advanced pumping solutions for the UK’s critical water infrastructure. We combine decades of experience with a progressive investment in technology to deliver robust, reliable, and compliant systems designed for long-term performance. We specialise in the design and in-house manufacture of water and wastewater pumping equipment built to withstand the demands of the water sector. Our proven resilience and expertise have made us a trusted supplier to major UK Water Utilities and the Ministry of Defence. Capabilities Our core capabilities include: Bespoke water boosting systems for network resilience. Packaged pumping stations for sewage and wastewater management. Durable pumping equipment engineered for all sectors. Integrated lifecycle support and maintenance services. Design & Manufacturing Excellence Our end-to-end project management ensures quality and accountability from concept to commissioning: Advanced 3D CAD Design and Building Information Modelling (BIM) support for seamless project integration. In-house fabrication and assembly using 316L Stainless Steel as standard for superior corrosion resistance and asset longevity. A state-of-the-art, fully equipped UK manufacturing facility ensuring quality control and supply chain security. Lifecycle Support for Critical Infrastructure Our dedicated Service Division ensures the operational reliability of your assets: Emergency support and nationwide services to ensure uninterrupted service. Professional installation, commissioning, and planned maintenance contracts. All KGN engineers are CSCS certified, CRB checked, and trained for confined space work, ensuring safe and compliant service on critical infrastructure sites. KIWA Certification KGN Pillinger is the only UK company holding KIWA certification for both: Above-ground AV and EV variable speed booster sets. Below-ground UPOD Underground Plant Room. This dual certification underscores our commitment to meeting the highest industry standards for quality, compliance, and energy efficiency. To discuss your specific project requirements, contact our engineering team: 📞 0208 681 0097 | 📧 sales@kgnpillinger.com | 🌐 www.kgnpillinger.com

PBJ Engineering Services Ltd
Do you need Thermal Hydrolysis Plant operational support, training and maintenance? Does your critical water process equipment require contract support and safety assurance? Visualise your assets and maintain operational efficiency through our 360 degree image capture. Invest in your operations through our professional training and technical support services. PBJ Engineering delivers a range of services to support your wastewater treatment and process facilities – we specialise in THP systems and Steam Boiler services, including CEA and BOAS accreditation. Our team is available nationally to support you, on a contract, project or emergency basis. Supporting your facility and team with a programme custom designed to your needs, typically includes elements of: Whole System Contracts Consultation and Best Practice Commissioning and Maintenance Optimisation and Monitoring Refurbishment and Rebuild Component Fabrication and Supply Training for BOAS and CEA accreditation Some of our typical on-site activities include full capabilities in; Thermal Hydrolysis Plants Steam Boilers Sludge Dewatering Processes Water Treatment Coil and Heat Exchangers Pumps Our ancillary support services includes; 360O Image Capture – Virtual Plant Training and Maintenance Boiler Log Books – Custom design & print Boiler House design – Advice and guidance Equipment – Hire services and component spares Our priority is the safety of all personnel and the operational efficiency of your facilities. We work with you and your team, to maintain and support your infrastructure – protecting your people, investment and optimising your asset performance. Our team is qualified with CITB / SMSTS, Achilles, and CEA / BOAS. Project involvement includes: Thames Water: Basingstoke THP (commissioning, operation, training, optimisation, maintenance) Beckton THP (energy surveys) Chertsey THP (operation, training, optimisation) Crawley THP (commissioning, operation, training, maintenance, part supply) Crossness THP (operation, optimisation, energy reduction, training, energy surveys) Longreach THP (operation, training, optimisation) Oxford THP (operation, optimisation, fault finding) Riverside THP (water treatment installation, design, energy surveys) Severn Trent: Finham THP (operational support) Strongford THP (operation, training) Southern Water: Goddards Green THP (operational support & performance monitoring) Others: Nestles – Trowbridge – steam boiler operational contract (24 hour call out) Heathrow airport – hot water boiler – scale cleaning

Quantum Engineering Developments Ltd
Quantum Engineering Developments Limited specialises in the design, construction installation and commissioning of surge control systems, compressed air systems and booster pump sets. Surge Control Systems Surge conditions, or ‘water hammer’ can occur due to starting or stopping a pump, or failures in the power supply, controls or valves. Quantum Engineering is the leading UK supplier of surge vessels and related control equipment for the alleviation of this effect. All systems can include a patented QUBE controller, developed especially for surge vessel and accumulator control in complex variable flow rate and multi-pump systems. Packaged Booster Pump Sets The company supplies booster sets suitable for applications in final effluent and potable water booster pumps for sewage and water treatment installations. Control Panels Quantum Engineering specialises in the construction of multi-compartment control panel suites to suit the requirements of most UK water authorities. Electrical control panels are available with relay, PLC and microprocessor controlled logic systems, including variable speed drives and soft start, as well as conventional DOL and STAR/DELTA starters. Accreditation All systems are factory tested in house, and are assembled and fitted to meet current statutory requirements, including UK pressure systems legislation and DWI Regulations 25 and 31. Recent Contracts QED supply and install surge vessels via both main contractors and direct with the end users, to nearly all of the UK water companies on both new and replacement/refurbishment projects. What can Quantum do for you today?

Salix River and Wetland Services
Salix River & Wetland Services are bioengineering technical specialists, involved in the supply, contract and design elements of river, wetland and coastal projects. Salix has extensive experience working within all river types across the UK, providing innovative vegetated, sustainable solutions for soil erosion and wetland creation. SUPPLY Our in-house product range specifically developed for erosion control and habitat creation includes Coir Rolls, Coir Pallets, Rock Rolls, Rock Mattresses, Rock Bags and the world’s highest performing range of Composite Turf Reinforcement Mats – VMax C350 & C500. We also provide hydraulically applied solutions such as TerrAffix. We have the largest native wildflower and wetland plant nursery in the UK. Salix are the only company to manufacture coir rolls and pallets within the UK, providing a massive reduction in carbon. Salix rock products allow natural sediment accretion and vegetation establishment, unlike harder solutions such as rock armour or gabions. CONTRACTING Salix’s contracting division undertake works for local authorities, public bodies, utility companies, main contractors & private clients, having been involved in a diverse range of projects across the UK. Salix has unrivalled specialist equipment for fluvial environment, including a Mackenzie ‘Muck’ Spider excavator. The Spider has four independent legs, with the ability to access logistically challenging of sites. Salix also has long reach excavators, floating pontoons, hydroseeders and truxor available for a diverse range of specialist fluvial and intertidal activities.

SAVECO Environmental Limited
SAVECO Environmental Limited is a member of the globally operating WAMGROUP – market leaders in bulk materials handling since 1968. SAVECO provides state-of-the-art solutions to customers in the United Kingdom and in the Republic of Ireland, providing a comprehensive product range of machines and equipment designed for effluent pre-treatment and sludge treatment in both municipal and industrial wastewater treatment plants, as well as livestock farming and biogas plants. Delivering innovative, market-oriented, and industrially manufactured products, SAVECO has a proven track record of success – working on major projects with Tier 1 & 2 Contractors as well as leading water utilities. SAVECO is determined to supply the most comprehensive range of equipment available to deliver a one-stop solution to its customers. SAVECO assures customers in any place in the world the highest possible quality product and service at a fair price.

Sewaco Ltd
Sewaco Ltd specializes in design, manufacture, supply and construction of purpose built plant and equipment for use in water supply systems and treatment of municipal sewage and industrial waste water. Our range of products includes: HYCOVER Static & Rotary distributor systems (from 5 l/s up to 980 l/s flow range) with optional auto cleanse and electro pneumatic belt drive mechanism, respectively. HYRATE Polytower biofilter systems using modular plastic media for: High Rate (BOD/COD reduction), upstream of existing treatment plant. Secondary ( BOD removal only or combined BOD removal/Nitrification). Tertiary Nitrification applications, downstream of existing secondary treatment processes. HYRATE Polytowers can easily incorporate natural ventilation or air extraction systems for odour control purposes, as required. Factory built timber support matrix for secondary modular plastic media support. Modular media installation and re-packing undertaken by our experienced site team.

SPP Pumps Ltd
For more than 140 years SPP Pumps has been a leading designer and manufacturer of centrifugal pumps and associated systems, a global principal in design, supply and servicing of pumps, pump packages and equipment for a wide range of applications and industry sectors. This includes water and wastewater treatment, oil and gas production, airports, hotels, construction, mining and for large industrial plants. Low life cost and environmental considerations are fundamental design priorities. With its exceptional expertise and experience, the company’s robust, trusted engineering has provided critical performance across the water industry. As a UK manufacturer, SPP are a leading supplier of clean and wastewater pumps to the Water Industry and has long established Framework agreements with many of the major Utilities throughout the UK and Northern Ireland. SPP Pumps has extensive experience of designing and delivering highly efficient ‘Pump as Turbine’ (PaT) solutions capable of rapid return on investment. Small hydro-electric power production provides a convenient, cost-effective source of renewable energy.

Steve Vick International Ltd
Steve Vick International (SVI) is dedicated to delivering cost-saving solutions for damaged, redundant or outdated underground pipework. Since its foundation in 1981, SVI has been at the forefront in developing products and techniques for the repair, renovation and decommissioning of pipes. Predominantly our work has been in the gas industry but increasingly we are undertaking projects in the water and nuclear sectors. We are the UK’s leading producer of Pipe Coil Trailers and offer a range of Pipe Handling equipment such as Handlers, Crackers and Cutters. Some of our latest innovations include the PE Pipe Cutter, the Pipe Feeder for Pre-Insulated coiled pipe, PE Live Head for Live Mains Insertion, the Perpetual Pipe Pusher, FBOS (Foambag Operation on Stubs) and SMARTester. WATER: For over 20 years water utilities and their contractors in the UK and overseas have used our pipe handling equipment to improve their efficiency and safety. Today our products include Pipe Handlers, Pipe Coil Trailers and Pipe Cutters as well as our patented DRAINBLOCK™ and RATBLOCK™ sealing systems. GAS: In the UK we are major suppliers to all the gas distribution networks. Many of the techniques we have pioneered have become the preferred methods of working in the industry and our resin foam sealant products and associated equipment are key to many of the cost-saving renovation processes used. NUCLEAR: SVI offer solutions to the problems associated with decommissioning and sealing disused pipework, ducts, sleeves and ventilation shafts. Our technology can also be designed for the mass filling of large and complex voids and is a lightweight alternative to cement grout. We have worked at Hinkley, Sellafield, Harwell, Chapelcross and Hunterston. CONTRACT SERVICES: A rapidly expanding part of our business is our Contract Service department who are well known for their work in the field of renewing and repairing underground gas pipes, for the UK Gas Distribution Networks. However, they are becoming increasingly involved in projects being undertaken by water utilities, electricity providers, rail networks, civil engineers, construction companies and local councils. This reflects the range of skills and expertise available to solve on-site problems associated with pipe repair, renovation, and diversion. Located strategically around the UK the highly skilled team can provide a fast response, emergency repairs and a rapid call out service which is offered 24 hours a day, 7 days a week. HIRE: We offer specialist plant and equipment for the Utilities Industries. Products available for hire include our Pipe Handlers, Perpetual Pipe Pusher, Pipe Coil Trailers, Rapid Rotary Cutters, Rapid Window Cutters, MACAW Pipe Crackers, CRACKERJACK and Mini Purge. All our hire equipment comes with onsite support from our highly experienced engineers and our products are fully maintained and serviced at our depots. All equipment is also available to purchase. SMARTester: SMARTester is the wireless pressure test system, that ensures absolute traceability and best practice. The system combines: SMARTester pressure sensor, an intuitive App and a Dashboard database of test evidence. Together the 3 components work to give you confidence that your tests are highly accurate, fully compliant and that evidence is traceable.

Vogelsang
Vogelsang are suppliers of Rotary Lobe pumps which are typically used in the waste water treatment sector to pump raw sewage and sludges, where the dry solid content is between 6% and 15% (by weight). Their use on an anaerobic digestion facility on a sewage treatment plant is very common application. The pumps are able to pass foreign bodies, can handle on a suction lift application (with a repeated self priming requirement) and are largely insensitive to dry running. The reversibility of the lobe pumps makes them suitable for membrane applications where running the pump in reverse allows for a cleaning of the membrane. We also offer inline RotaCut macerators and XRipper twin shaft grinders / shredders which are used to protect a downstream pump. These products too are in widespread use in the UK waste water treatment sector and are bespoke specified and manufactured to suit a specific application. The XRipper is suitable for both pipework and open channel applications and as with all of our products are robust and can be easily serviced by the end user without the need to remove it from site, ensuring the whole-of-life cost of ownership is minimised. We operate out of a facility in Crewe in Cheshire that has a comprehensive spares parts store. The company can provide both a field service and repair workshop service.

Wireless CCTV Ltd
Temporary Security and Live Monitored CCTV WCCTV provides rapid deployment CCTV towers and perimeter intrusion detection (PID) systems backed by a fully managed service, including remote monitoring, installation, maintenance and connectivity. Our security solutions are designed to protect water treatment plants and wastewater facilities from theft, trespass and vandalism, ensuring uninterrupted operations at the UK’s critical water sites. Our systems are currently protecting both live sites and facilities undergoing construction and maintenance works across the UK.
Process Selection and Regulatory Compliance in Municipal Sewage Treatment
Municipal wastewater treatment plant design is governed by a hierarchy of regulatory requirements that flow from the Clean Water Act through NPDES permit conditions to specific technology-based and water quality-based effluent limits. Technology-based effluent limits (TBELs) establish minimum treatment performance—secondary treatment under 40 CFR Part 133 requires BOD₅ removal to 30 mg/L and TSS to 30 mg/L on a monthly average. Water quality-based effluent limits (WQBELs) may be significantly more stringent based on the assimilative capacity of the receiving water, adding nutrient limits (total nitrogen, total phosphorus), toxicity requirements, and temperature constraints.
Process selection for secondary treatment typically comes down to activated sludge variants, trickling filters (with or without recirculation), and rotating biological contactors for smaller systems. Extended aeration, sequencing batch reactors (SBR), and membrane bioreactors (MBR) offer advantages in footprint, effluent quality, and operational flexibility. MBR systems produce consistently high-quality effluent suitable for reuse applications and eliminate secondary clarifiers, but their higher energy consumption and membrane replacement costs must be weighed against these advantages over the plant's design life.
Nutrient removal—biological nitrogen and phosphorus removal—has become a near-universal requirement in new and upgraded municipal plants discharging to nutrient-sensitive water bodies. Biological nutrient removal (BNR) process configurations such as A²/O, four-stage Bardenpho, and UCT (University of Cape Town) process achieve nitrogen and phosphorus removal through carefully staged anaerobic, anoxic, and aerobic zones. Chemical phosphorus removal using alum or ferric chloride supplementation provides insurance against biological process upsets but generates additional chemical sludge. Providers experienced in BNR process optimization are essential for plants operating under tight nutrient permit limits.
Frequently Asked Questions
What is the difference between secondary and tertiary sewage treatment?
Secondary treatment removes dissolved and suspended organics through biological processes—activated sludge, trickling filters, or equivalent—achieving typical effluent quality of BOD₅ below 30 mg/L and TSS below 30 mg/L. Tertiary (or advanced) treatment adds one or more additional process steps to meet more stringent effluent requirements: sand or membrane filtration to reduce TSS further, biological or chemical nutrient removal to reduce nitrogen and phosphorus, and disinfection (UV, chlorination) before discharge. Many NPDES permits for discharges to sensitive water bodies now require tertiary or advanced treatment as a baseline standard.
How do I determine if my activated sludge plant needs biological nutrient removal upgrades?
Check your current NPDES permit for total nitrogen (TN) and total phosphorus (TP) effluent limits. If TN limits are below 10 mg/L or TP limits are below 1 mg/L, you likely need a biological nutrient removal configuration. If you are approaching permit renewal in a nutrient-impaired watershed, anticipate that these limits will be applied or tightened. Request a feasibility study from a plant design firm evaluating BNR retrofit options for your existing tankage configuration before committing to a full upgrade design.
What causes bulking in activated sludge and how is it corrected?
Bulking—poor sludge settling caused by filamentous bacterial overgrowth—raises the sludge volume index (SVI) above 150–200 mL/g and can cause clarifier overflow and permit violations. Filamentous bulking is typically triggered by low dissolved oxygen in the aeration basin, low F/M ratio (extended SRT), nutrient deficiency, or septic influent. Corrective actions include DO aeration adjustment, selective chlorination of the return activated sludge (RAS) to selectively kill filaments, and process control changes to the SRT. A knowledgeable process engineer should diagnose the filament type microscopically before applying corrective measures, as different filaments respond to different interventions.
What should I evaluate when selecting a design-build contractor for a new wastewater treatment plant?
Evaluate the contractor's experience with the specific process configuration you require (activated sludge, MBR, BNR), not just general wastewater construction. Review their commissioning track record—ask specifically how many plants have achieved permit compliance within six months of startup and what the most common commissioning challenges were. Confirm that the contractor's process performance guarantee is backed by a financial bond or retention mechanism, and clarify who is responsible for process optimization during the warranty period if the plant struggles to meet permit limits.