Water
Engineering our most precious asset
A world-leading, design, engineering and technology consulting services provider



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Engineering our most precious asset
A world-leading, design, engineering and technology consulting services provider



Ranked among the world’s top 20 engineering and technical advisors for major water infrastructure, Ayesa is at the forefront of sustainable water management. We protect vital ecosystems, minimise environmental impact, and transform waste into valuable resources.
Our multidisciplinary teams deliver across the full water cycle, from strategic water resource planning and reservoirs to treatment and pumping stations, desalination, water conveyance, flood resilience, stormwater tunnels, river and canal engineering, effluent wetlands, and major water infrastructure.
In 2025, Ayesa grew to 13,000 professionals, united by a shared purpose: to develop solutions that shape a more sustainable, resilient, and digitally driven world.
Our services deliver higher performance for clients, shareholders, employees, and communities.
// Dams, Reservoirs and Major Water Infrastructure
// Water Treatment and Desalination
// Water Resource Management
// Water Conveyance and Distribution
// Drainage, Groundwater and Irrigation
// Flooding and Rivers
// Waste Management
// Environment and Sustainability
// Liquefied Natural Gas (LNG)
// Pipelines
// Production Facilities
// Refining Facilities
// Storage and Terminals
// Ports & Harbours
// Marine Structures
// Coastal Modelling & Engineering
// Marinas & Waterfronts
// Subsea Pipelines
// Arts and Culture
// Education
// Healthcare and Research
// Heritage and Conservation
// Office and Commercial
// Residential and Hotels
// Sports and Leisure
// Technology and Data Centres
// Urban Planning and Landscaping
// Solar Energy
// Onshore and Offshore Wind Power
// Biomass
// Hydroelectric Power
// Hydrogen and Renewables Gases
// Energy Storage
// Thermal Generation
// HV Transmission and Distribution
// Airports
// Bridges and Structures
// Highways and Roads
// HSL, Railways
// Land Management
// Metros, LRT and Tramways
// Stations and Terminals
// Transportation Systems
// Tunnels and Underground Spaces




// Logistics Plants and Distribution Centres
// Metallurgical and Transformation Plants
// Agri-Food Plants
// Mining Facilities
// Chemical and Petrochemical Plants
// Yeast and Life Sciences

We offer the highest standards of design, project management and stakeholder collaboration to realise optimum project solutions. Our engineering consultants are among the very best in their fields. Continuous involvement in challenging projects maintains and enhances our high standards of technical excellence.
We invest in our staff to deliver a positive, enriching, safe and empowering work experience at Ayesa. We are committed to equality, diversity and inclusion to provide a place where everyone can thrive. We invest significantly in training and development to keep our staff at the cutting edge of their industry. Our focus is on positively influencing those SDGs most applicable to us in our role as a leading engineering consultant. Everything from CO2 emissions, water reduction, social value, health and wellbeing, community engagement, apprenticeships, and safe working.
Our company is built on relationships and superior client care. We deliver on our unwavering commitment to assist our clients in achieving their desired results. We are agile and responsive and build a collaborative framework across stakeholders for project success.
We are seasoned in managing projects and supervising construction phases of projects across the project lifecycle. We help clients “bridge the gap” across all relevant stakeholders within a project. We seek to understand the needs, constraints, opportunities and to optimise solutions.
Getting a project off to the right start and mitigating any delays helps to keep costs down - Our team has forged close working relationships with environmental authorities and regulators throughout the regions we operate in, enabling us to expeditiously progress projects through the permitting, construction, verification and site closure.
We offer innovation with a deep understanding of environmental issues such as climate change and sustainability, waste to energy, renewables to deliver maximum value to clients.

We have extensive experience across a broad range of sectors. We currently sit on a number of frameworks, such as Irish Water, Port of Cork, Oil and Pipeline Agency, Waterways Ireland, Gas Networks Ireland, Irish Rail, Fusion 21 and Translink.
Our culture focuses on developing strong working relationships with clients who continue to work with us based on the value we provide. Our clients are in both the public and private sector and range from major companies and national regulatory organisations to smaller regional organisations providing optimum solutions for significant infrastructure projects and local sites.
We keep our clients informed of the implications of legislative changes to their businesses and manage stakeholder engagement to help progress projects in a profitable yet environmentally compliant manner. Our proactive approach helps you to benefit from our expertise in a constantly changing regulatory environment.
We advance safety, applying rigorous processes that manage technical, environmental and social risks and hold ISO 45001:2018 – the internationally recognised standard for occupational health and safety management systems.
We provide engineering and design consultancy services across ten sectors: marine and coastal, geoscience, buildings, transportation, energy, environment, water, flooding, waste management, and conservation.
At Ayesa, we take a holistic approach to water management that addresses the full spectrum of challenges facing utilities and communities today. From tackling climate change impacts and building resilience into infrastructure, to balancing fluctuating demand and supply, we deliver solutions that are both technically robust and future-focused. Our work prioritises water quality, environmental sustainability, and longterm value, ensuring that every project delivers a strong return on investment—socially, economically, and environmentally. By integrating engineering, environmental science, and digital tools, we help clients navigate complexity and plan with confidence for the future of water.
Ayesa brings decades of experience delivering nationally significant infrastructure across transport, water, and energy. In Ireland, we are proud to sit on the engineering design framework for Uisce Éireann (Irish Water), supporting the delivery of strategic infrastructure that serves communities and supports economic growth. Our team understands the complexity, scale, and regulatory environment required to deliver major projects successfully.
We are a trusted partner on complex, high-value schemes where collaboration and delivery certainty matter. Working alongside government bodies, such as the Office of Public Works (OPW), and local authorities across Ireland, we’ve built long-standing relationships based on our ability to deliver—whether it’s a multi-million-euro flood scheme or a critical water infrastructure upgrade.
Our extensive portfolio spans water, transportation, energy, buildings, and the environment—giving us the insight to approach every project with both fresh thinking and tried-and-tested methodologies. With projects delivered across Ireland and globally, we tailor our services to local needs while applying international best practices.
We thrive in complex environments, acting as integrators across disciplines, stakeholders, and project phases. Whether coordinating with local
county councils or national agencies, our role is to streamline delivery, align priorities, and ensure that every part of a project moves in sync—on time and on budget.
With over 80 technical disciplines under one roof, Ayesa offers true multidisciplinary services, from civil and structural engineering to environmental science, geotechnics, and digital engineering. This integrated approach results in more effective collaboration, faster delivery, and better long-term value for clients and communities.
Our inhouse capabilities in digital modelling— including BIM, GIS, and hydraulic and hydrological simulation—allow us to optimise designs and communicate solutions clearly. These tools are essential in infrastructure and flood relief projects, where precision, scenario testing, and stakeholder engagement are key.
Ayesa, has been involved in numerous water and wastewater schemes across Ireland, including the Blanchardstown Regional Drainage Scheme. In this €88 million project, Ayesa served as the consulting engineer, lead designer, and Employer’s Representative, delivering over 3 kilometers of new wastewater lines and a 30,000 m³ stormwater storage facility to enhance capacity and environmental protection in the Greater Dublin Area.
Ayesa is a long-term delivery partner to the Office of Public Works (OPW), working closely with the OPW and local authorities on both major and minor flood relief schemes across Ireland. We’ve delivered more than 25 schemes nationally, including the €57m Arklow Flood Relief Scheme, €30m Bandon Flood Relief Scheme, €10m GraiguenamanaghTinnahinch Scheme, €10m Donegal Scheme, and €7m Cavan Scheme. Our end-to-end expertise covers feasibility, design, environmental assessment, stakeholder consultation, and construction support—protecting communities and building resilience into the future.


Feasibility & Assessment Ground Analysis
Stakeholder Engagement planning Tendering & Procurement
Technical Consulting
Employer’s



SUB SECTORS
Dams, Reservoirs and Major Water Infrastructure
Wastewater, Water Treatment and Desalination
Drainage, Groundwater and Irrigation
Water Conveyance and Distribution
Flood Risk Management & Rivers
Asset and Resource Management
Sustainable Solutions


SAUDI ARABIA – National Water Company (NWC) Program - Ayesa awarded a 95 million contract to deliver major water infrastructure across the Kingdom
Ayesa has secured its largest water project contract to date in Saudi Arabia, valued at €95 million. Under this contract, they are designing 190 sanitation and drinking water distribution projects across four regions: south, west, northwest, and north. The scope includes the development of water storage tanks, pumping stations, treatment plants, purification facilities, and extensive distribution networks, all aimed at enhancing water supply reliability and efficiency.
IRELAND - Ayesa part of the Irish Water Framework (Uisce Eireann)
Ayesa, through the acquisition of ByrneLooby, has been a key contributor to Ireland’s water infrastructure development through its involvement in the Irish Water (now Uisce Éireann) Framework. As one of eight suppliers appointed to this framework, Ayesa has played a significant role in delivering engineering design services across various sectors, including drinking water, wastewater quality, capacity, and new infrastructure, supporting Irish Water’s €5.5 billion capital investment programme.
OPW: Working alongside government bodies, such as the Office of Public Works (OPW), and local authorities and county councils across Ireland, we’ve built long-standing relationships based on our ability to deliver—whether it’s a multi-million-euro flood scheme or a critical water infrastructure upgrade. Notable projects include the €57 million Arklow Flood Relief Scheme, which will protect hundreds of properties and enhance the public realm; the €7.3 million Cavan Town scheme, designed to safeguard over 100 buildings; and the Springfield scheme in Clonlara, featuring embankments and pumping infrastructure. Additional work includes the €9 million Graiguenamanagh-Tinnahinch scheme tackling fluvial flooding, and the Bandon Flood Relief Scheme, which involves river dredging and the construction of new defences.
UK - Bringing global capability and local presence to key AMP8 Projects supporting utilities, contractors and frameworks
Ayesa will support AMP8 and drive AMP9 by leveraging our deep infrastructure expertise, local delivery teams, and data-driven design approach to help water companies achieve their sustainability, affordability, and resilience goals—drawing on our experience from major reservoir, network, and treatment plant projects across the world. As number 14 in Water Supply and top 10 in Treatment and Desalination globally, we are a leading water consultant with proven track record and a rich portfolio of delivery.
At Ayesa, we engineer intelligent water supply solutions that serve communities, industries, and ecosystems—today and into the future. Our multidisciplinary teams support the full lifecycle of water infrastructure, from strategic planning and feasibility to detailed design, delivery, and asset optimisation.
We collaborate with public authorities such as Uisce Éireann (Irish Water), FLI Water in the UK, local authorities, regulators, and private stakeholders to develop systems that are efficient, climate-resilient, and aligned with long-term sustainability goals.
Whether it’s delivering regional schemes to meet growing demand, optimising treatment facilities, or integrating digital tools for smarter operations, we bring deep technical expertise and local insight to every project. Our solutions respond to the realities of climate change, shifting demand, and evolving regulation—ensuring every litre delivered is safe, secure, and sustainable.
This approach underpinned our work on several key projects: we fast-tracked the North East Roscommon Water Supply Scheme, managing design, procurement, and construction of critical infrastructure identified on the Remedial Action List; we supported the €55m North Fringe Water Supply Scheme with design services for 22km of water mains, a water tower, pumping station, and reservoir beside the M50; and we delivered the detailed civil, structural, and hydraulic design for the Vartry Water Supply Scheme, securing water for over 200,000 people while achieving significant cost and programme savings through value engineering.
Services at a glance
Water Source & Resource Planning, Treatment Plant Design & Optimisation, Water Transfer & Network Design, Modelling and delivering pipelines, pumping stations and gravity systems, Storage Infrastructure, Design of reservoirs, towers, tanks and emergency supply systems, Digital Modelling & Data Analytics, Enhancing design and operations through digital twins and GIS-integrated tools, Regulatory & Stakeholder Engagement, Climate Resilience & Futureproofing,








Saggart Reservoir is a covered facility spanning a vast 100 Million Litres – enough to fill 40 Olympic-sized swimming pools
The Saggart Reservoir Project involved constructing a new covered treated storage reservoir to safeguard the water supply to homes, essential services, and businesses in the Greater Dublin Area. The upgrade marks the first significant investment in the existing Saggart waterworks since the 1950s. This new, state-of-the-art reservoir will house over 100 million liters of treated drinking water, or the equivalent of 40 Olympic-sized swimming pools, supplied from the Ballymore Eustace treatment plant. The scheme also includes a new electrochlorination plant building and associated infrastructure. In terms of size and scale, the new reservoir can store enough water to supply almost 300,000 homes for one day.
Coffey Construction engaged Ayesa to provide detailed civil, structural, geotechnical, and hydraulic design, as well as PSDP services. Ayesa supported Coffey Construction in delivering this essential infrastructure, with construction of the new reservoir and associated pipelines commencing in March 2021 and completing in October 2024.
INNOVATION / VALUE ADD
To minimise the impact on local residents, the project implemented reduced working hours, enhanced environmental monitoring, and traffic management, while also prioritising sustainability through energy-efficient site planning, high GGBS concrete use, and extensive recycling of demolition materials and excavated soils.

Location: Saggart South County Dublin Country: Ireland
Capital Value: £118m
Dates: 2021-2024
Project Name: Saggart Reservoir
Client: Coffey Construction, Uisce Eireann (Irish Water)
Capacity: 100,000 m3
Population: 650,000 PE
Services at a glance
Civil, structural, geotechnical, and hydraulic design, PSDP (Project Supervisor Design Process) services, Construction support and design integration with contractor (Coffey)


The Saline Water Conversion Corporation (SWCC) plays a vital role in desalinating seawater and is currently modernizing its infrastructure by replacing aging facilities with new seawater reverse osmosis (SWRO) plants in Jubail. These upgrades incorporate renewable energy and wastewater treatment technologies in line with Saudi Vision 2030.
Ayesa collaborated with SEPCO III and subcontractor Metito to contribute to the design, engineering, procurement, and supervision of the project. Using advanced technologies like Distributed Control Systems (DCS) and Seawater Reverse Osmosis (SWRO), Ayesa ensured design verification, construction supervision, and commissioning, ensuring optimal performance and efficiency.
Ayesa’s expertise in managing Middle Eastern projects from feasibility through to commissioning was crucial to the success of Jubail II. With teams in both Saudi Arabia and Spain, we leveraged deep local knowledge of technical, regulatory, and procurement procedures. Strong collaboration with SWCC, SEPCO III, and Metito ensured the project’s success. Jubail II is now a reliable source of water for Riyadh and surrounding urban centers.

Location: Al Jubail
Country: KSA
Capital Value: £11b
Dates: 2020-2024
Project Name: Jubail ii desalination plant
Client: SEPCO III, Metito
Capacity: 400,000 m3 Daily
Population: 684,000 PE


The General Directorate of Water Infrastructure of the Andalusian Regional Government, part of the Ministry of Agriculture, Fisheries, Water, and Rural Development, launched this project to upgrade the Cuevas del Almanzora dam’s infrastructure before the aging valves and gates became obsolete, which could lead to significant water losses.
In addition to replacing the outdated components, the Andalusian government decided to modernise the electromechanical systems by adding remote-control capabilities. This upgrade allows operators to monitor and manage the system remotely, avoiding the need to physically access the difficult-to-reach outlet, located several dozen meters below the dam.
In 2023, Ayesa completed the renovation of the Cuevas del Almanzora Reservoir’s drainage system in Almería, Andalusia. The project included the design, installation, and modernization of control panels, intake valves, discharge gates, and hydraulic systems. Advanced technologies, such as a SCADA system for real-time data analysis and remote monitoring through CCTV and fiber-optic communications, were integrated to improve operational efficiency. These upgrades enhance safety, ensuring safe reservoir drawdowns and protecting nearby areas, including Cuevas de Almanzora, Los Lobos, Villaricos, and Palomares, from flooding.
Executed in a 10-month timeframe, in partnership with ACT SISTEMAS and Construcciones Alpi (JV 50/50), this project not only increases operational efficiency but also significantly enhances regional safety. Ayesa added value to the Cuevas del Almanzora Reservoir modernization by designing and installing control systems, including SCADA for remote monitoring, and modernizing valves, gates, and mechanical components. The project improved operational efficiency, safety, and flood protection for nearby areas. Ayesa also enabled real-time monitoring through fiber-optic communication, ensuring continuous oversight by local authorities.

Location: Almeria
Country: Spain
Capital Value: Not disclosed
Project Name: Cuevas del Almanzora Reservoirr
Client: General Directorate of Water Infrastructure of the Andalusian Regional Government
Capacity: 100,000 m3
Population: 120,000 PE

At Ayesa, we specialise in wastewater management, offering expertise in sludge processing, odour control, and advanced treatment solutions. Our services cover the full treatment process, from physical, biological, and chemical treatments to recycling and network integration, all while prioritizing environmental concerns such as odour control, containment, and visual impact.
The Arklow Wastewater Treatment Plant, delivered six months ahead of schedule and on budget for Uisce Éireann, sets a global standard with its innovative façade, seamlessly blending functionality with Arklow’s industrial heritage. The €140m plant will eliminate raw sewage discharge, enhancing water quality in the Avoca River and Irish Sea. Ayesa provided comprehensive consultancy services, managing all phases from design to delivery. As Employer’s Representative, Ayesa oversaw construction and commissioning, ensuring smooth execution and adherence to quality standards.
In partnership with ASCO, Ayesa upgraded Al Kor’s Sewage Treatment Works, expanding capacity for a population of 36,000 while ensuring operational continuity. Through value engineering, we optimized costs with a focus on resilience, maintenance, and sustainability, while incorporating HAZOP and CHAZOP reviews for safety and efficiency.
For the Swords Wastewater Treatment Plant, Ayesa expanded capacity to 90,000PE to support the growing commuter town. We minimized odour impact using advanced modelling and mitigation measures, ensuring fully enclosed processes and applying tertiary treatment for effective odour control.
Services at a glance
Site surveys and environmental impact assessments, Hydrological and geotechnical studies Regulatory compliance reviews, Preliminary and detailed design (civil, structural, mechanical, electrical), Sludge management and treatment design, Project Management & Procurement, Cost estimation and budgeting, Scheduling and project coordination,Procurement support and contractor management Health & Safety, Retrofitting and upgrading existing systems, Integration of new treatment technologies






The Atotonilco wastewater treatment plant in Hidalgo, Mexico, is part of the Sustainable Water Programme for the Mexico Valley, which aims to have 100% of city and industry wastewaters treated by 2025. The €560m plant is one of the largest of its kind in the world, treating wastewater from a population equivalent to 12.6 million of Mexico City’s inhabitants. The plant uses biological and chemical processes to treat up to 4.5 million cubic metres of water a day, and has a cogeneration system that harnesses biogas from the digestion process for maximum energy savings. Ayesa led the consortium that provided supervision, engineering, and commissioning services for the project. The plant generates 33MW of electricity and reduces greenhouse gas emissions by around 1 million tons of CO2 per year
Ayesa led the supervision of the construction and commissioning of the world’s largest wastewater treatment plant in Mexico. The plant treats 70% of the wastewater generated in the Valley of Mexico and uses two processes to treat the water, with a treatment capacity of 42 cubic meters a second, rising to 50.
• This plant will help to reduce greenhouse gas emissions by around 1m tons of CO2 per year.
• Climate-resilient and sustainable processes: The plant performs two separate processes: one biological process in winter and at times of drought, a chemical process during the dry season from May to October.
• Access to sustainable energy, water and sanitation systems
• The wastewater water had previously been used for agricultural irrigation on 90,000 hectares, posing a health hazard to the local citizens
Award: Infraestructuras 360º award from the InterAmerican Development Bank (IDB) in recognition of the comprehensive implementation of a sustainability strategy.

Location: Atotonilco, Hidalgo state
Country: Mexico
Capital Value: €560m
Client: Conagua (Mexican Water utility)
Sector: Water
Sub Sector: Wastewater & Wastewater Treatment
Expertise at a Glance
Lead Supervisor of Construction and Commissioning, Comprehensive Testing During Commissioning Phase, Project Finance Management


Across Spain’s Guadiana Basin
Spain’s Directorate-General for Water has appointed Ayesa Engineering to deliver a comprehensive risk study for 34 dams managed by the Guadiana River Basin Authority. As climate pressures intensify, State-owned water infrastructure faces growing exposure to extreme weather, prolonged drought and high magnitude flood events.
This programme will modernise how risk is understood, governed and prioritised across the basin. It will provide the Administration with a robust, forward-looking framework to protect communities, safeguard water security and ensure that critical assets are resilient to future climate conditions.
The dams within the Guadiana basin are vital to regional and national resilience. They secure water supply for households, agriculture and industry in one of Spain’s most drought-prone regions, support hydropower generation and provide essential flood protection for downstream communities. Their performance is central to Spain’s long-term water strategy.
Ayesa will deliver a comprehensive risk, failure-mode and hydraulic analysis for each of the 34 dams. The programme begins with a detailed assessment of potential failure mechanisms, evaluating both the likelihood of occurrence and the consequences in terms of flooding, loss of life and economic impact.
The team will apply advanced hydrological and hydraulic modelling to test dam performance under future climate scenarios, including extreme events such as overtopping, high magnitude flooding and breach conditions. The analytical framework combines probabilistic methods, numerical modelling, stability assessments, internal erosion studies, Monte Carlo simulations and bespoke software developed specifically for this programme.The outcome will be a unified risk profile for every asset in the portfolio.
At the heart of the programme is the creation of an advanced decision-support and risk-governance platform. This will bring together all datasets, models and analyses into a single digital environment, enabling the Administration to: Compare risk consistently across the entire dam portfolio, prioritise interventions based on risk and cost, Allocate State investment more effectively, Strengthen long-term asset management and planning The methodology aligns with Spancold Guide No. 8 on Risk Analysis, placing Ayesa among the front runners applying this new national framework at scale.
Dam safety and portfolio-wide risk assessment, Failuremode and consequence analysis, Climate-resilient hydrological and hydraulic modelling, Extreme event and breach scenario simulation, Geotechnical and structural performance assessment, Probabilistic risk analysis and decision-support tools, Digital platform for asset prioritisation and investment planning

Location: Guadiana River Basin, Spain
Country: Spain
Capital Value: €1.4m
Client: Directorate-General for Water, Ministry for Ecological Transition and the Demographic Challenge (MITECO), EU Next Generation Funds
Sector: Water
Sub Sector: Dams, Reservoirs and Major Water infrastructure

1. International Project of the Year 2025 – BCIA NCE (British Construction & Infrastructure Awards)
2. Project of the Year 2025 – Irish Construction Industry Awards
3. Downes Medal 2025 – Engineers Ireland, for Outstanding Engineering Achievement
4. ENR Global Best Projects Award of Merit (Wastewater Category) 2025 – Engineering NewsRecord (ENR)
5. President’s Award for Excellence 2025 – Irish Planning Institute, for Best Practice in Planning and Sustainability
6. Infrastructure Winner 2025 - Irish Planning Institute
7. Public Choice Award (2nd Place) 2025 – Royal Institute of the Architects of Ireland (RIAI)
8. Sustainability Award 2025 – Royal Institute of the Architects of Ireland (RIAI)
9. Public Building of the Year 2025 – Royal Institute of the Architects of Ireland (RIAI)
10. Subsea Pipeline Project of the Year 2023 – Pipeline Industry Guild (UK), for the Marine Outfall (awarded by Van Oord)
11. Engineering Excellence Awards 2025 – Civil Engineering Project of the Year
12. Engineering Excellence Awards 2025 – Engineering Project of the Year

Arklow Wastewater Treatment Plant prevents discarge of raw sewage into the Irish Sea
For decades, Arklow was one of the largest towns in Ireland discharging raw sewage directly into the sea, breaching EU environmental regulations and impacting the Avoca River and Irish Sea. In response, Uisce Éireann committed €140 million to deliver a state-of-the-art wastewater treatment plant, designed to eliminate pollution, safeguard public health, and provide scalable capacity to serve a future population of up to 36,000.
Ayesa was appointed by Uisce Éireann (Irish Water) to provide consultancy services across all phases of this critical wastewater treatment plant (WWTP) project. Our role builds on our extensive experience in delivering water infrastructure in the area, having previously been appointed as Engineer for the Arklow Water Supply Scheme, The Arklow Main Drainage Scheme, and the Arklow Flood Relief Scheme (FRS). This deep understanding of the entire water cycle in the catchment allowed us to take a holistic, strategic approach, particularly in managing the shared interfaces between wastewater, flooding, and climate resilience.
Having previously delivered the Arklow Water Supply Scheme and Flood Relief Scheme, Ayesa brought deep knowledge of local hydrology, enabling a joined-up strategy that considered flooding, wastewater, and climate resilience as an integrated system. We led complex hydraulic and marine modelling (e.g. InfoWorks ICM, hydrodynamic studies) to define optimal sewer alignments and marine outfall routes. Our designs balanced performance, cost, and environmental outcomes, supporting faster planning approvals. We managed a web of stakeholders—residents, businesses, Wicklow County Council, marine authorities, and utility providers—supporting Irish Water through land acquisition (CPOs), public hearings, and community engagement, minimising local disruption and building public trust. As Employer’s Representative, we provided contract and risk management, cost control, and quality assurance during construction and commissioning. This ensured works were delivered six months ahead of schedule and on budget—despite marine and urban complexity.

Location: Wicklow
Country: Ireland
Dates: 2012-2025
Capital Value: £140m
Project Name: Arklow Wastewater Treatment Plant
Client: Uisce Eireann (Irish Water)





At Ayesa, we take a holistic approach to drainage and groundwater design, balancing engineering precision with environmental responsibility. Our solutions are informed by advanced hydraulic and hydrological modelling, detailed ground investigations, and a clear understanding of climate change impacts. We work to futureproof infrastructure, reduce flood risk, manage groundwater sustainably, and support the longterm viability of wastewater and stormwater systems.
Arklow Main Drainage: Our modelling identified critical weaknesses in the local drainage network, especially in low-lying South Green. We designed new interceptor sewers and a marine outfall to eliminate river discharge and reduce flooding.
Blanchardstown Regional Drainage Scheme:
One of the largest capital projects undertaken - ayesa was appointed as the lead designer We designed deep underground storage tanks (30,000m³) and a 3.2km pipeline, using trenchless techniques. Groundwater and river modelling ensured safe, sustainable construction near sensitive environments.
Shanganagh-Bray Transfer Pipeline: We led the design of a 6km transfer pipeline, storm tank, and pumping station, serving a catchment of 248,000 people, while addressing groundwater inflows and storage needs.
From urban wastewater management to regional flood resilience, our drainage and groundwater work supports sustainable growth, environmental compliance, and climate adaptation.
Services at a glance
Drainage strategies, Sewer network, Intakes and Outfall Design, Urban and City design, SuDS advice, Impermeable area surveys/runoff design, Drainage network modelling, Culvert design, Hydrology and Hydromophology, Ground analysis, Environmental assessments

Highly Commended award in the Infrastructure category at the Irish Concrete Society’s 40th Annual Awards in April 2023. This recognition was for the project’s innovative design and execution, which contributed to sustainability and resilience in Dublin’s growing commuter belt.
Overview
Dublin’s Tolka Valley wastewater network was under severe pressure due to rapid urban growth, leading to frequent overflows of untreated wastewater into the River Tolka. This posed significant environmental, public health, and compliance risks.
Our Work
Consulting Engineer, Lead Designer, and Employer’s Representative
>3.2 km of micro-tunneled wastewater pipeline
>30,000 m³ of underground stormwater storage
>Duplicate 9C sewer line and new pumping station
>Advanced odor control, MEICA systems, and environmental protections
>A remote-operated pumping system from a groundlevel control room for real-time monitoring
>Use of trenchless construction techniques to minimise disruption in the urban park setting
Innovation/Value Add
Sustainable, cost-efficient design: Our integrated hydraulic, civil, structural, and MEICA reference design during procurement reduced lifecycle costs significantly. Environmental leadership: Ayesa’s in-house environmental team prepared the Environmental Impact Statement, securing planning permission and demonstrating no negative impact on local habitats or Waterville Park. End-to-end delivery: Ayesa fast-tracked planning, led contract preparation, managed tender evaluations, and oversaw construction and commissioning.
WINNER: Highly Commended award | Infrastructure Category | The Irish Concrete Society 49th Annual Awards 2023.
FINALIST: Civil Construction Project of the Year 2023.
FINALIST: Irish Construction Excellence Awards 2024.

Completed Scheme
Expertise at a Glance
Lead design and consulting engineers, MEICA, Employer’s Representative, Environmental Impacts, trenchless tunnelling, Advanced flow techniques, Utility Management
Location: Tolka Valley, Dublin
Dates: 2013-2024
Country: Ireland
Capital Value: £88m
Project Name: Blanchardstown Regional Drainage
Client: Uisce Eireann (Irish Water)
Capacity: Capacity of approximately 30,000 cubic meters

Ayesa provides full-spectrum advisory and engineering services for water transmission and wastewater systems—from master planning and design through to construction supervision. Our expertise spans tunneling methods (TBM, SEM, micro-tunneling), geotechnical analysis, and engineering in complex conditions such as seismic zones, urban corridors, and contaminated ground.
We design and oversee every element of conveyance infrastructure: pipelines, trunk mains, canals, pumping stations, flow control systems, intakes, outfalls, and distribution networks. Whether moving raw water from marine intakes, delivering treated water for agriculture, or managing wastewater through complex sewer networks, our solutions prioritize efficiency, resilience, and sustainability.
Solving Real-World Challenges
With a significant portion of global drinking water lost to leaks, Ayesa supports utilities in modernizing infrastructure through smart networks, advanced leak detection, and optimized distribution. Our goal: reliable supply, cleaner environments, and more resilient communities.
Driving Innovation
We harness advanced tools—including digital twins, hydraulic modeling, and VR visualization— to enhance performance, reduce risk, and avoid costly delays.
Services at a glance
Water Transmission & Distribution: pipelines, trunk mains, canals, and pumping stations to ensure efficient water conveyance, engineering of sewer networks, stormwater systems, and wastewater treatment plants, including marine outfalls and interceptor sewers. Advanced Conveyance Solutions: Utilisation of tunneling methods such as TBM, SEM, and micro-tunneling for complex infrastructure projects. Geotechnical & Structural Engineering: Analysis and design for infrastructure in challenging conditions, including seismic zones and contaminated sites. Digital Engineering & Innovation: automated irrigation systems and soil moisture sensors to improve water use efficiency and crop health.






The Kingdom of Saudi Arabia has made substantial investments in desalinated water production as part of its Vision 2030 strategy, allocating approximately $5 billion annually to water infrastructure to meet future demand. With the integration of phases 3 and 4, the Shuqaiq complex became one of the largest reverse osmosis desalination plants in the world, with a total supply capacity of 650,000 m³/day. This project formed part of one of the most complex water transmission systems in the Kingdom. From the Shuqaiq 3 desalination plant on the Red Sea coast, treated water was pumped inland, overcoming an elevation gain of more than 2,000 meters and requiring tunneling through mountainous terrain. These exceptionally challenging conditions demanded advanced hydraulic design, pressure management, tunneling engineering, and robust surge protection systems, alongside energy optimization strategies to ensure the reliability and resilience of the full transmission route.
As the lead engineering design consultant for the Shuqaiq 3 desalination plant project, Ayesa worked closely with Acciona, the EPC contractor, overseeing the development and implementation of critical water transmission infrastructure. Ayesa’s role encompassed a range of engineering design services and technical support for the project, which was one of the most complex in Saudi Arabia’s water sector. This was further strengthened by Ayesa’s acquisition of ByrneLooby, who took on the detailed design of Package B and C, covering the reservoir and pumping station infrastructure. Key highlights of the scope included: Full design of a 3,125 m³/hr pumping station, 8 km of 1,600 mm gravity and 1,200 mm rising mains, Structural and civil design for a 170,000 m³ water tank foundation, with provisions for future expansion Multidisciplinary engineering services: structural, architectural, civil, hydraulic, surge analysis, M&E, instrumentation & controls, and cathodic protection Associated site works, including the design of a water quality monitoring building, drainage, and access roads. In respect of Packages B and C, Ayesa combined state-of-the-art geotechnical software with a comprehensive understanding of the site’s soil characteristics, wave, and current loadings to optimise the design, reducing the number of piles required, and delivering both cost and time savings.

Location: Jizan
Country: KSA
Capital Value: $610m
Project Name: Al Shuqaiq SWRO Phase 3
Client: SWCC, Metsco
Capacity: 2 million PE





Ayesa is a leading flood consultant with a respected legacy and recognised excellence in flood risk management. Our engineers play a vital role in protecting communities from the impacts of flooding— whether at coastlines, along rivers and waterways, or from surface water, groundwater, or overwhelmed drainage networks.
We design and implement river engineering strategies to reduce flood risk. This includes channel restoration, bank stabilization, and floodplain management. Our teams apply hydraulic modelling and flood risk assessment techniques to develop effective river management plans.
Risk Assessment: We conduct comprehensive assessments to evaluate flood risk and quantify its potential impact on communities, businesses, and infrastructure.
Sustainable Solutions: Ayesa recommends flood and river management approaches that prioritise long-term sustainability—balancing environmental protection, community needs, and economic feasibility.
Mitigation Plans: We develop detailed flood mitigation plans that integrate structural and non-structural measures to reduce the impact of flooding on lives, properties, and livelihoods—delivering sustainable project outcomes.
Ayesa has been involved in numerous flood relief schemes across Ireland, both major and minor, in partnership with the Office of Public Works (OPW). Arklow Flood Relief Scheme (€57 million), Bandon Flood Relief Scheme (€30 million), GraiguenamanaghTinnahinch Flood Relief Scheme (€10 million), Donegal Bundles Flood Relief Scheme (€10 million), Cavan Flood Relief Scheme (€7 million)
Services at a glance
Flood Risk Management: Comprehensive flood risk assessments, including modelling, mapping, and impact analysis. River Engineering: Channel restoration, bank stabilization, and floodplain management to mitigate river flooding risks. Hydraulic Modelling: Advanced techniques to assess flood behaviour and design mitigation measures. Sustainable Flood Solutions: Development of integrated flood mitigation strategies, combining structural and non-structural measures. Environmental Impact Assessments:

Bandon, a historic town in West Cork and an Area of Potential Significant Flood Risk (APSR), had suffered repeated flooding due to capacity issues in the Bandon and Bridewell Rivers. In response, the Office of Public Works (OPW), in partnership with Cork County Council, launched one of Ireland’s first Catchment Flood Risk Assessment and Management (CFRAM) pilot schemes, appointing Ayesa as lead consultant in 2011.
Ayesa led the scheme from feasibility through to handover, providing hydrological and hydraulic modelling, structural and geotechnical design, environmental planning, and public engagement. We acted as Employer’s Representative and developed the Flood Risk Management Plan, securing ministerial sign-off. Our design scope included new flood defence walls and embankments, underpinning and mini-piling of Bandon Bridge, a new three-span steel footbridge, rock ramps for fish passage, and reinforced concrete culverts. We also oversaw 3.6 km of river dredging and sediment management, working closely with Inland Fisheries to monitor environmental impacts. The Bandon Flood Relief Scheme was officially opened on December 9, 2022, with a plaque unveiled by Minister of State for the Office of Public Works, Patrick O’Donovan.
Tasked with delivering a low-intervention solution, Ayesa developed a scheme that operates passively with no ongoing human input—achieved through intelligent design and strategic planning. Beyond functionality, the project enhanced public realm and resilience, with new drainage infrastructure, rip-rap revetments, and extensive brick paving and landscaping that now integrate seamlessly into the historic fabric of Bandon.

Completed Scheme
Location: Bandon, Co Cork
Country: Ireland
Dates: 2011-2022
Capital Value: £30.5 m
Project Name: Bandon Flood Relief Scheme
Client: OPW, Cork County Council


Water utilities today are under unprecedented pressure to do more with less—maintain aging infrastructure, meet tightening regulations, reduce losses, and adapt to the growing impacts of climate change. At Ayesa, we help clients navigate these challenges through proactive asset management, advanced digital tools, and datadriven decision-making. Whether it’s extending the life of critical infrastructure, reducing unaccounted-for water, or ensuring resilience to future shocks, our integrated approach supports utilities, frameworks and D & B and O & M contracts.
1. Managing Aging Infrastructure: Extending Asset Lifespan
Challenge: Water utilities often deal with aging infrastructure that requires significant investment for maintenance and upgrades, leading to increased costs and service disruptions.
Solution: Through proactive asset management and life-cycle analysis, Ayesa supports utilities in extending the lifespan of critical infrastructure. Our team provides strategies for rehabilitating and upgrading aging assets, ensuring optimal performance while minimizing costs and downtime.
2. Reducing Water Loss: Improving Leak Detection and Efficiency
Challenge: Unaccounted-for water (UFW) due to leaks and inefficiencies leads to significant financial and environmental losses for water utilities.
Solution: Ayesa implements advanced technologies, such as smart networks and IoTbased systems, to monitor and detect leaks in real-time. Our cutting-edge leak detection systems help identify and repair leaks faster, reducing water loss and improving the overall efficiency of water distribution networks.
3. Ensuring Regulatory Compliance: Meeting Evolving Standards
Challenge: Compliance with increasingly stringent water quality and environmental regulations can be complex and costly for utilities.
Solution: We provide expert consultancy to ensure that water utilities meet both local and
international regulatory standards. Our designs include solutions for water quality monitoring, sustainable wastewater management, and the integration of renewable energy, ensuring compliance without compromising service delivery.
4. Enhancing Operational Efficiency: Reducing Energy and Operational Costs
Challenge: Water utilities often face high operational costs, particularly energy consumption for water pumping and treatment processes.
Solution: We optimize water and wastewater infrastructure through smart system design, energy-efficient technologies, and automation.
5. Optimizing Resource Allocation: Managing Limited Water Resources
Challenge: With climate change and population growth, managing limited water resources while meeting demand is a growing concern for utilities.
Solution: Ayesa uses advanced data analytics and hydraulic modelling to forecast future water demands and optimize resource allocation. We integrate smart water systems that use real-time data to balance supply and demand, enabling utilities to make informed decisions and ensure a reliable, sustainable water supply.
6. Future-Proofing Infrastructure: Preparing for Growth and Climate Change
Challenge: Water utilities must future-proof their infrastructure to handle increasing demand and the impacts of climate change, such as rising temperatures and more frequent droughts.
Solution: Through smart infrastructure planning and climate resilience strategies, Ayesa ensures that water utilities can adapt to changing conditions. We focus on building flexible, scalable systems that can accommodate future growth and withstand extreme weather events, ensuring long-term sustainability.




At Ayesa, we leverage Building Information Modeling (BIM) and modelling to enhance the design, construction, and ongoing management of water infrastructure, ensuring greater efficiency, precision, and long-term sustainability across all phases of a project.
Digitalisation of 15 dams in Spain: In 2024, Ayesa was awarded a contract to digitalise 15 dams operated by Spain’s Duero River Basin Authority, funded by the EU’s Next Generation programme. Using Building Information Modeling (BIM), Ayesa developed detailed 3D models of key dams such as Barrios de Luna, Riaño, and Juan Benet. The project improved safety, operations, and maintenance by integrating real-time data from drones, LiDAR, and inspections into a central cloud-based platform—demonstrating Ayesa’s leadership in applying digital engineering to critical water infrastructure.
ELAN VALLEY AQUEDUCT: As part of Severn Trent’s overall strategic resilience plan, the ageing Elan Valley Aqueduct required rehabilitation. The aqueduct delivers vast quantities of water to Birmingham City, sourcing water from the Caban Reservoir in Powys, Wales. The project required deep excavation around the 110-yearold aqueduct. The project was challenging, as an ageing structure meant restricted movement on site, and the water system was to remain fully operational throughout construction. We successfully developed efficient design solutions which minimised requirements for temporary support making significant savings for the client.
HYDRODYNAMIC MODELLING: Ayesa specialises in hydrodynamic modelling, which involves studying the movement of fluids influenced by factors such as tides, wind, waves (metocean), gradients (river flows, weirs, dams, and turbines), and interactions between water bodies like oceans, rivers, and cooling water discharges. The movement of water can affect solid bodies within the fluid, such as structures, seabed features, and land boundaries, influencing their behavior. Ayesa’s expertise in understanding and quantifying these complex interactions is crucial for the effective and sustainable development of infrastructure and assets.




Natural processes to treat wastewater, manage stormwater, and restore ecosystems—offer a sustainable, cost-effective alternative to traditional infrastructure. At Ayesa, we take a holistic view of the water cycle. That means recognising the value of these solutions not just for their technical performance, but for their environmental and social co-benefits. Constructed wetlands, for example, reduce nutrient loads, filter contaminants, and support biodiversity—while blending naturally into their surroundings.
By embedding nature-based systems into water infrastructure planning, we help clients future-proof their assets, boost climate resilience, and contribute meaningfully to net-zero goals. These approaches are especially powerful in rural and peri-urban areas, where decentralised, low-energy treatment is often the most viable option.
While upgrading conventional infrastructure remains critical, we must also champion greener, integrated alternatives. From wetlands to renewables, these innovations offer lasting value for both people and the planet. Water Capabilities Brochure / Sustainability
Nature-Based & Sustainable Drainage Systems (SuDS), Constructed & Effluent Wetlands
1. PROJECT PLANNING AND FEASIBILITY STUDIES
Water Demand Forecasting: Assessing future water needs and planning accordingly. Feasibility Studies: Technical, economic, and environmental feasibility assessments. Regulatory Compliance: Ensuring all designs meet local regulations and environmental standards.
2. DESIGN AND ENGINEERING
Hydraulic Engineering: Design of water distribution networks, sewage systems, pumping stations, and treatment facilities.
Civil & Structural Engineering: Design of reservoirs, dams, pipelines, pumping stations, and other critical infrastructure.
MEICA: Design and integration of mechanical, electrical, instrumentation and control systems for water and wastewater treatment and distribution, ensuring safe, efficient and reliable operation across the full asset lifecycle.
BIM: Integrated Building Information Modelling for concept design, detailed coordination, construction and operational handover, providing a central source of truth for all disciplines. Our BIM-led approach supports design assurance, clash detection, regulatory sign-off and asset management, enabling faster approvals, fewer errors on site and a smoother transition from design to build and operation.
Surge Analysis: Assessing pressure fluctuations in transmission systems to ensure reliability.
Geotechnical Engineering: Soil analysis and tunneling engineering for complex environments.
Water Quality Engineering: Ensuring safe and sustainable water quality management.
3. CONSTRUCTION AND IMPLEMENTATION
Construction Supervision: Overseeing the construction of water infrastructure, ensuring that quality and safety standards are met.
Procurement Support: Assistance in selecting contractors, equipment, and materials for the project.
4. PROJECT MANAGEMENT CONSTRUCTION & OWNERS ENGINEER
Project Coordination: Managing timelines, budgets, and resources across the full project lifecycle - acting as Employer’s Representative, PSDP Services
Risk Management: Identifying and mitigating potential project risks, ensuring that projects are completed on time and within budget.
Stakeholder Management: Ensuring clear communication between all project stakeholders, including clients, contractors, and local authorities.
Quality Control & Assurance: Ensuring that the engineering solutions are implemented to the highest quality standards.
5. COMMISSIONING AND TESTING
System Integration: Ensuring all systems work together seamlessly
Commissioning: Full-scale testing of water infrastructure systems to ensure they meet performance requirements.
Performance Monitoring: Monitoring system performance during the commissioning phase and beyond to ensure long-term reliability.
6. OPERATION AND MAINTENANCE
Ongoing Maintenance: Developing a strategy for the maintenance of water treatment facilities and infrastructure to ensure long-term operation.
Upgrades & Optimisations: Providing recommendations for upgrading infrastructure to improve efficiency, sustainability, and water quality.
Smart Monitoring: Implementing smart water networks for continuous monitoring and real-time data management.
Renewable Energy Upgrades: Ayesa also provides renewable energy upgrades, integrating energy-efficient systems and sustainable technologies into infrastructure projects to support environmental goals and long-term energy resilienc
7. ENVIRONMENTAL SERVICES
Environmental Impact Assessments (EIA): Evaluating the potential environmental impact of water projects.
Sustainability & Resource Management: Designing solutions that focus on the efficient use of water resources.
Land Remediation: Providing expertise in land remediation and brownfield site regeneration to enhance water management and support sustainable development.
> Hydraulic modelling
> Network calibration and verification
> Pipeline route selection and route proving
>Utility diversion management & NOC procedures
>Demand analysis and water balance assessment
>Chlorine residual analysis
>Storage assessment and design
>Pressure optimisation and pumping analysis
>Pumping station design
>Value engineering
>Tender and contract documentation
>Chemical processes (coagulation, flocculation, precipitation)
>Ultra filtration
>Reverse osmosis
>Disinfection system
>FEED reports
>Primary, secondary and tertiary process designs
>SCADA, control and alarms/electrical/mechanical rotary
>and static/process/hydraulic/structura
>Septicity control
>Sludge treatment & recycling
>Industrial wastewater treatment analysis and process selection
>Industrial process design - heavy metal recovery, metal precipitation, coagulation, flocculation, sedimentation
>Pumping station design
>Micro-tunnelling design
>Odour control
>STP and IWT operating and maintenance
>Pipeline designs
>TSE reuse
Surge and stress
Wastewater collection design, sewer computer modelling
Coordination with stakeholders, FEED, DD, IFB documents
FLOOD RISK MANAGEMENT
>Topographical & bathymetric survey management
>Aerial /Lidar/ DTM surveys
>Hydrological studies
>Surface water modelling
>River modelling
>Coastal modelling
>Flood risk assessments & appraisal
>Flood risk/hazard mapping
>Feasibility studies
>Design of flood defence systems
>Natural flood risk management measures
>Flood defence condition surveys
>Flood early warning systems
>Hydrological studies
>Coastal modelling
>Flood estimation
>River modelling
>Flood risk management plans
>Hydrodynamic modelling & assessment
>Environmental Impact (EI) & Appropriate Assessments (AA)
>Drainage strategies, Urban and City design
>SuDS advice
>Impermeable area surveys/runoff design
>Drainage network modelling
>Culvert design
>Ground analysis
>Environmental assessments

>Data-driven optimisation modelling
>Cost/benefit analysis
>Asset performance predictions
>Programme management
>BIM & digital engineering
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