Our executive team

Our Executive team is responsible for the day-to-day running of the business and is made up of the Interim Executive Chairman and Chief Financial Officer (CFO) as well as seven functional directors.


Ian Marchant - Interim Executive Chairman

Learn more about our Board members


Brandon Rennet

Chief Financial Officer/Executive Director

Appointed: March 2017

Relevant skills:

  • Strong expertise in leading the execution of multi-billion-pound funding, primarily in the public debt capital markets and creating sustainable financing structures to support corporate sustainability aims
  • Valuable utility experience combined with public policy exposure

Relevant experience:

Brandon brings substantial financial leadership success to his role as Chief Financial Officer having spent three years of a ten-year tenure as Managing Director of Finance at regulated energy company, SSE Plc. While in post he led the execution of more than £7 billion of funding and initiated a finance transformation programme.


John Beaumont

Digital, Strategy and Transformation Director

Appointed: September 2017

Relevant skills:

  • Experience driving complex change in regulated companies
  • Proven background using digital technology to create customer obsessed businesses

Relevant experience:

John directs digital transformation and strategy with a focus on improving customer outcomes and reducing operating costs. He leads strategy development, IT, data analytics and the application of digital technologies across the business.

Prior to Thames Water he spent 12 years directing customer focused and operation-led transformations as a Partner at Bain & Company where he worked expansively in the digital and technology space across a variety of infrastructure-heavy industries. His early career was spent at Deloitte and PA Consulting.


Lynne Graham

Human Resources Director

Appointed: January 2020

Relevant skills:

  • Experience in designing and delivering complex cultural and organisational change programmes
  • Skilled in leadership development; MSc in Coaching and Behaviour Change

Relevant experience:

Lynne is accountable for the HR function, covering the entire employee life cycle including talent attraction and selection, reward and benefits, payroll and administration, learning and development, employee relations and organisational development.

She has led major change programmes that have delivered significant value through cost reduction and through productivity improvements by driving an engaged culture.

Prior to Thames Water she has operated at Executive and Main Board level in diverse sectors – Eurostar (rail); British Gas (gas utility); Westbury Street Holdings (hospitality); Yodel (logistics).


Nicola Cocks

Regulation Director

Appointed: October 2019

Relevant experience:

Nicola has over fifteen years of utility regulation experience. This includes ten years at the energy regulator Ofgem, where her roles included acting as Project Manager for some of Ofgem’s most critical and high profile projects, including the DPCR5 price control review, the Retail Market Review, Ofgem’s first REMIT investigation and the joint State of the Market Assessment with the OFT and CMA, which led to the referral of the sector to the CMA in June 2014. Nicola was Head of Projects and Programmes at Ofgem, transforming the capability and effectiveness of the business in delivering projects that achieved most value for Ofgem and for consumers.

Nicola spent over five years at KPMG, as Director of Power and Utilities. The role involved both business development with key clients and delivery of high quality engagements, particularly focussed on regulatory and economic analysis and project delivery. This included acting as strategic advisor to a number of UK leading network companies on their price control reviews, in providing regulatory insight and assistance to companies facing compliance and/or enforcement action from their regulator and in undertaking agreed-upon-procedure reviews of companies’ regulatory reporting prior to submission.


Lawrence Gosden

Asset Management Director

Appointed: October 2011

Relevant skills:

  • Extensive expertise within the water industry over 30 years
  • Substantial experience leading infrastructure-based operations

Relevant experience:

Lawrence leads our asset management capability ensuring we have a deliverable asset management plan. He has had a number of senior leadership positions across Thames Water and was, most recently, the Chief Operating Officer.

Prior to this he was Managing Director for Wastewater and has also held the positions of Asset Director and Capital Delivery Director where he led the delivery of the company’s £1 billion annual capital programme.


Kelly Macfarlane

Customer Experience Director

Appointed: January 2017

Relevant skills:

  • Demonstrable track record in customer experience transformation within complex, regulated businesses
  • Strong leadership capability to deliver digitally-led, agile customer service operations focused on first-time issue resolution

Relevant experience:

Kelly is responsible for all Thames Water customer interfaces and teams including residential metering, billing and service support, and Non-Household and Developer Service operations.

She previously held a number of senior operational roles at Openreach, the infrastructure division of BT Group and a variety of key regulatory, commercial and operational roles for companies including Deloitte Consulting, Tiscali and npower. Kelly is a Vice President of the Institute of Customer Service.


George Mayhew

Corporate Affairs Director

Appointed: August 2019

Relevant skills:

  • Significant experience in corporate affairs
  • Proven background in stakeholder and government relations for organisations across a range of sectors

Relevant experience:

Before joining Thames, George was Group Corporate Affairs Director at National Grid, where he was responsible for the company’s reputation and stakeholder management strategy. His role included policy development, government and media relations, employee communications, corporate responsibility and brand.

Prior to this, George was Chief of Staff to the CEO of BAE Systems for four years and previously held various government relations roles at MBDA Missile Systems, Centrica and Granada TV.


Steve Spencer

Operations Director

Appointed: April 2017

Relevant skills:

  • Significant experience of the water industry over 25 years
  • Proven track record of improving performance and delivering strong operational results

Relevant experience:

Steve oversees the efficient running of water and wastewater operations. He is responsible for delivering high quality drinking water and reducing leakage, alongside safely processing wastewater, transforming it into renewable power and returning clean water to our rivers.

His career has been dedicated to the water sector. Not only has he held senior leadership positions across Thames Water, he has also worked at Southern Water and MWH Australia.


John Bentley

Capital Delivery Director

Appointed: October 2019

Relevant skills:

  • Experience of developing and implementing different operating models and bringing together people from multiple organisations to deliver investment needs
  • Shaped capital investment plans across three price reviews

Relevant experience:

John is a chartered civil engineer and has 28yrs water industry experience working for Severn Trent Water. During this time he managed £billion, complex capital investment programmes. As the Capital Delivery Director, John’s responsible for the safe and efficient delivery of AMP6 investment through the eight2O Alliance partners. He is leading the development of, and transition to, a new capital operating model which will secure more value for customers throughout AMP7.