CEO and President
Mercedes Sierra is the Chief Executive Officer of SENER US. She is a structural engineer with more than 35 years of experience managing complex international projects in both the private and public sector. Before being appointed CEO, she was SENER’s Chief Innovation Officer.
Since joining SENER in 1985, Mercedes work has spanned a variety of engineering disciplines including aerospace, energy, infrastructure and transportation. Since 2018, Mercedes oversees the company’s growth and development in North America.
Mercedes previously acted as Chair of SENER’s Innovation Committee leading research and development forums, venture capital funding and start-up incubators.
In the public sector, Mercedes has acted as an advisor to the US Department of Energy, the European Space Agency and Spain’s Innovation Agency.
Mercedes has served on a number of Boards and Executive Committees including SENER, Hispasat Canarias, Orbital Recovery Corporation or Galileo Systems and Services.
She is very passionate about empowering professional women in traditional male environments and would like to have some more time to push her research in Renaissance Art Studies.
Juan Lema, PE
Rail Program Manager, Rail Transport
Juan Lema is a project manager and civil engineer with more than 20 years of professional experience in designing, planning, construction management and project management of high-speed rail (HSR), freight rail, regional rail and other transportation projects in the United States and Europe. Juan is a California PE.
Since joining SENER in 2015, Juan has worked with clients and federal, state, and local agencies, including California High-Speed Rail Authority (CHSRA), Southern California Regional Rail Authority, San Joaquin Regional Rail Commission, Altamont Corridor Express, UPRR, BNSF Railway and Caltrans. He has recently been working on various projects in California including the Cross Bay Transit project in the San Francisco Bay area, the Stanislaus River Rail Bridge in Stanislaus and San Joaquin Counties, and the California High Speed Rail program in Fresno to Barkersfield, and the Palmdale to Burbank project sections.
Juan has served as Construction Manager and Project Manager in the Administrator of Railway Infrastructures (ADIF) in Spain and as Senior Advisor for rail policy in the Spanish Department of Transportation where he helped to develop and implement one of the largest high speed rail (HSR) networks in Europe and the second largest worldwide, with more 2,000 miles of HSR lines now in operation.
Juan has also been Vice Chairman of the Amtrak Northeastern Corridor Partner Forum, Senior Advisor to the United States Federal Railroad Administration in the Office of Railroad Policy and Development where he collaborated with the USDOT in the development of a HSR program for the U.S., and an advisor to top officials in Spain including the Minister and Deputy Minister of the Department of Transportation.
Being a rail enthusiast and an adventurous traveler, Juan has experienced the joy of riding rail and transit systems in all six continents.
Project Manager, Rail Transport
Roberto Rodriguez is a civil engineer with more than 18 years of experience managing and coordinating railway infrastructure projects. He has worked in the private sector for SENER, as well as in the public sector for the Spanish Railway Infrastructure Manager (ADIF).
Roberto is an experienced manager of complex railway projects including transit, conventional and high-speed rail. He has broad international experience, having worked on projects in Europe, USA, the Middle East and Latin America. He is seasoned in all the different development phases including feasibility studies, preliminary design, detailed design, and operation and maintenance.
Roberto is a Civil Engineer with huge experience working with multidisciplinary teams, as many railway projects require. Two of his areas of expertise are rail track design and Fire Life & Safety facilities for tunnels. He has experience also managing interfaces between the different rail systems and subsystems, performing risk analysis for rail lines and directing risk-based design projects.
Roberto is the Project Manager on the Verification & Validation subcontract for the California High Speed Rail, Construction Package 2-3, providing validation, verification and self-certification services to assure an integrated system is built. He is also Deputy Project Manager on the California High Speed Rail for the Palmdale to Burbank Section. He is overseeing the development of the Environmental Impact Report/Environmental Impact Statement, preliminary design engineering, geotechnical investigation, and public outreach.
Roberto was a member of CEN/TC 256/WG 32 Railways Standards Group leading the development of the European Standard EN 15273 (Railway Applications – Gauges) and is a member of the Spanish Association of Civil Engineers.
Carline di Mario
Project Engineer - Civil
Carline di Mario is a civil engineer with more than 15 years of experience, specializing in roadway and drainage design.
Carline has a deep understanding of the adaption of industry standards with extensive engineering experience in roadway improvements and drainage design involving compilation and analysis of technical reports and the use of Autodesk and Bentley software design tools. She has successfully contributed to both design-bid-build and design-build projects.
Carline currently provides project engineering services in the development of the California High Speed Rail. She is the designer for drainage, utilities, civil and environmental areas for both the Palmdale to Burbank section and the Tulare-Kern Counties section. Carline also provides supports the alignment and grading of the projects including the preparation of drawings, reports and Bill of Quantities.
Prior to joining SENER in 2020, Carline acted as a project engineer for transportation projects in Miami and Chicago.
Wei Guo, P.E
Senior Project Manager, Civil Engineer
Wei Guo is a Professional Engineer (CA) with more than 22 years of experience in railway/highway alignment design, tunnel design, alternative station study, special track work design, roadway network study, construction staging site design, street restoration, utilities and right of way design. Wei always emphasizes high quality project design service and provides other engineering services to his team.
Wei has a diverse engineering background, having taken on a number of roles including surveyist, civil/structure engineer, residential engineer, pursuit manager and project manager. As a manager, Wei has developed strategic plans to build civil/transit teams and set up standards for project proposals, designs and QA/QC. He has worked on a number of projects in California including the California High Speed Rail, I-10/Singleton Interchange improvements, and the Los Angeles International Airport.
Wei holds a master’s in civil engineering from the University of Southern California and a Bachelor’s degree in civil engineering from Changsha University of Science and Technology in China.
John Webber is a Chartered Engineer with more than 20 years of transportation experience in rail, highways and airports, across construction, design, design management, testing and commissioning and project management. John is experienced in the successful delivery of large, multi-disciplinary projects from inception to completion while consistently meeting tight timescales and budgets.
Prior to joining SENER, John served as a manager with the systems engineering team for the Automated People Mover Project, a design, build, finance, operate and maintain (DBFOM) contract with a total value of $5,000,000,00, which includes a 2.25 mile elevated guideway with six stations – three inside the Central Terminal Area (CTA) and three Outside, a Maintenance and Storage Facility and 3 Traction Power Substations.
Before that he served as Lead Design Organization Project Manager for the Great West Electrification Project in the UK for Balfour Beatty. While at Balfour Beatty he also worked on the North West Electrification Project in the UK, and the Northern Electrified Double Track Project in Malaysia. Before that he served as an Implementation Engineer working on telecommunications infrastructure projects for Atkins Global at Heathrow Airport.
John also served as a Tactical Communication Specialist in the British army.
Pursuit Manager and Corporate Secretary
Cristina Suarez is the pursuit manager of SENER US, working to expand operations in the infrastructure and transportation industries in North America. She is a licensed lawyer and holds a master’s in international business management. She recently graduated with high honors from the Master of Law at the USC Gould School of Law.
At SENER, Cristina wears multiple hats and her responsibilities include preparing tenders for RFP and SOQs for public and private clients in P3, design-build, and design-bid-build projects. She also provides in-house legal counsel in matters related to corporate governance, insurance, compliance and contract negotiations.
Prior to joining SENER, she worked for the Spanish Secretary of Commerce in Los Angeles fostering trade relations between the US and Spain. Before moving to Los Angeles from Spain, she worked as an international tax consultant for KPMG, amongst other firms.
Cristina loves to be an advocate for the public transportation industry and is an active volunteer of WTS-LA where she has been a member of the Colleague Outreach Committee since 2019.
Project Engineer Specialist – Systems
Lourdes Howard has over 19 years of professional experience working as a systems and project engineer. She is currently at SENER working on the California High Speed Rail Project and has 16 years of experience working as a systems engineer specializing in aerospace.
As a systems engineer, Lourdes has managed and collaborated with cross-functional teams throughout the project life cycle including the development, test and integration, acceptance, qualification, and production phases. Lourdes has also provided project engineering and risk management expertise to projects.
At SENER, she has provided systems engineering and project engineering support for requirements verification and validation of the California High Speed CP 2-3 Project. She has managed verification and validation activities to ensure compliance to contract requirements for technical contract submittals. In addition, she has interfaced with the Design and Quality teams to provide impact assessment of contract changes, design variances, and design changes to determine technical impacts to Verification and Validation submittals.
Prior to joining SENER, Lourdes was a systems engineer at Aerojet Rocketdyne and Boeing, including acting as lead systems engineer for a $200M rocket propulsion project and an IBM DOORS database administrator.
Alvaro Relaño, P.E.
Project Manager – Transportation
Rail Infrastructure Discipline Lead
Alvaro Relaño, P.E. has more than 30 years of experience as project manager and design leader in transportation and infrastructure engineering projects. Over the last two decades, he has successfully contributed to the planning, design and implementation of rail infrastructures around the world including the United States and Spain.
Alvaro has extensive experience in transport infrastructures, with an emphasis in the railway industry. His range of experience covers the planning and design of metro and tramway systems, high speed lines, conventional railway lines, passenger and freight lines. He has worked as a design manager and high speed rail (HSR) expert on several U.S. projects including providing engineering and environmental services for the Palmdale to Burbank section of the California High Speed Rail, the detailed design project for CP4 of the California High Speed Rail, the bid design for the Los Angeles Regional Connection, and the Union Station Master Plan. Amongs these, the Palmdale to Burbank project is one of the most outstanding and challenging endeavor he has been involved with, given the singularity and technical complexity of it.
Globally, he has also worked on high speed rail projects in Spain including the line on the Madrid-Barcelona-French Border and the Spanish Eastern High Speed Rail corridor from Madrid to Valencia (with more 600 miles in preliminary studies and 430 miles in detailed design studies), as well as in other rail projects abroad.
Alvaro holds a Master of Science degree in Civil Engineering from Universidad Politecnica de Madrid.
Guillermo Dierssen, P.E.
Chief Technical Engineer Geotechnical and Tunnel
Guillermo Dierssen is a registered Professional Engineer (CA, MD) with more than 35 years of experience as a civil engineer and project manager specializing in underground works and rail projects.
After beginning his career in Germany, where he earned a PhD degree in Civil Engineering from the University of Karlsruhe, with a thesis in soil dynamics and deep foundations, Guillermo joined SENER in 1994. He is a recognized expert in tunneling with extensive knowledge of the geotechnical field.
Guillermo has been the design manager of many challenging urban rail transport and tunneling projects internationally. He has successfully participated in many important rail (high speed, intercity and regional lines) metro and highway projects including the Los Angeles Metro’s Regional Connector, Maryland Metro’s Purple Line, California High Speed Rail, LA Outfall tunnel, Spain’s High Speed Railway Network, including the International High Speed link connecting Spain and France, the Port Said road tunnels under the Suez Canal, Barcelona Metro Line 9, etc.
He received the “Best Civil Construction Work of the Year 2009” award from the Spanish Institute of Civil Engineers for the Sol station, a large underground commuter railway station under the heart of Madrid.
David Martin, CSEP CFSE
Project Manager, Systems Engineer
David Martin is a systems engineering manager with more than 20 years of professional experience including Reliability, Availability, Maintainability, and Safety (RAMS), and systems assurance and requirements. He has led projects around the world involving INCOSE-based systems/software engineering, defense, aerospace, transport, telecommunications, energy and control.
David has broad experience in technical coordination and team management of large international projects. He has successfully completed projects involving satellite monitoring, SIL 4 equipment certification, avionics, railway transport, and wind farms monitoring. He has also successfully developed projects to a great level of detail, in the fields of artificial intelligence, parallel computing and nuclear physics. David has designed and led the integration of systems for California’s High Speed Rail, Barcelona’s Metro Line, the Doha Metro Line and the Dubai Metro Line.
David understands how to translate theory into practice and has successfully developed systems engineering and systems assurance activities to align with program, project, commercial and technical objectives. The California High Speed Rail CP2-3 V&V is one of his dearest projects, where he contributed to set up the workflows, data models, processes and tools for successful verification and validation of the Employer Requirements.
David holds both a Bachelor of Science degree and Master of Science degree in telecommunications and information technology and two master’s degrees – one in aerospace science and technology and one in software engineering. Being and astrophysics enthusiast, David is currently working on his PhD Thesis, which he develops in his free time.
Rail Vehicle Design and Rail Vehicle Systems Integration
Mark Turner has more than 30 years of experience in engineering design and technical development of railway rolling stock and vehicle systems integration. His roles have ranged from truck and suspension design engineer to technical design manager for complete vehicles.
Mark’s functional experience has included vehicle design studies from the preliminary phase through manufacturing, contract negotiation, testing and commissioning, configuration management, vehicle certification and vehicle warranty. Mark has a proven track record of managing multiple assignments concurrently.
He has extensive experience in international projects having worked in Australia, Taiwan, Korea, Spain, France, UK, Ireland, Canada, and USA, which has led to a clear understanding of international standards and their application.
Since joining SENER in 2016, Mark has worked as an engineer on the Angels Flight Funicular in Los Angeles, Canada’s Finch West Light Rail Transit, Ottawa’s new Confederation Line and Mexico’s Guadalajara Light Rail Transit.
One of Mark’s most significant and notable successes, and one which remains a personal highlight, was the design, delivery and commissioning of the new light rail vehicles and extension to an existing fleet of light rail vehicles to the Luas system in Dublin. The role involved coordinating design and manufacturing teams in Barcelona and La Rochelle in France, and managing the vehicle commissioning and integrated testing phase in Dublin.
Chief Technical Engineer – Railways
Joaquin Botella is a transport civil engineer with more than 33 years of experience in high-speed and conventional railway projects, both passenger and freight transport, and urban transport projects (metro and LRT systems), among others.
Joaquin joined SENER in 1989 and has worked on projects around the world including the United States, Mexico, Canada, Spain, Malaysia, Australia, Poland, France, Hungary, Ireland, United Kingdom, Portugal, UAE, Qatar, Oman and Chile. His vast experience includes design, consulting with public and private clients, financial entities, construction companies, and concessionaires.
As Chief Technical Engineer for SENER’s Railway sector, Joaquin is considered in SENER a reference in the railway area as a whole with an integrated and transversal approach to design that includes the areas of planning, layout, superstructure and railway systems, traction, rolling stock, as well as operation and maintenance, areas, including P3 projects.. He also acts as a representative for SENER in meetings with congresses in the United States and internationally.
Joaquin is a recognized expert in the industry and collaborates with national and international associations including the High Speed UIC Committee, Spanish Association of Professional Engineers, and the Public Transport International Association. He has provided expertise in the preparation of handbooks, papers and studies. He is considered as a reference in the areas of track and railway systems, as well as planning, alignment, superstructure, rolling stock, operation and maintenance.
Joaquin is a member of the Innovation Engine Committee of SENER and the SENER Strategic Business Unit of Transportation and Infrastructure.
When asked Joaquin about his favorite project this is what he responded:
It is very difficult for me to pick up one favorite project, but I will select three of them:
International high speed section between Figueras (Spain) and Perpignan (France): first high speed P3 project in Europe, very challenging that allowed me to grow as project manager managing international design partners and international constructors with a very tight schedule environment
Tenerife (Canary Islands, Spain) LRT, as I have been involved in the project since the very beginning (Tenerife railway master plan), concept design, detailed design until today running LRT operations audits
Abu Dhabi LRT (United Arab Emirates). Five challenging years of project. Unforgettable.