Meet our Management Team!


Howard Parry

Managing Director

Howard has over 45 years’ experience in Water Treatment Management and has a wealth of experience in the field. He was responsible for the introduction of several new and innovative products during his time with one of the world’s largest Water Treatment companies before forming GMS Services Limited in 1997. Howard is still passionate about the company ethos of providing high quality, value for money solutions to all water treatment related situations and ensures that all employees adopt this ethos.

Howard has overseen year on year growth of the business both in sales and client number and he puts this down to a dedicated professional team around him. Howard’s and his team’s experience has developed the business into a well-respected company within the industry that now supply services and solutions to both the Public and Private sectors including Councils / NHS / Mechanical Contractors / Chemical Manufacturing and Power Generation to name but a few.


Gemma Ollerton

Logistics Director

Gemma joined GMS Services in 2000 as Administration Officer, progressing to Office Manager before becoming Logistics Director.

Gemma has over 20 years’ experience with the company and deals with all personnel, staffing and logistics for GMS, assisting the team to ensure KPIs are achieved for clients and works are completed as smoothly and efficiently as possible.

Gemma is passionate about ensuring all staff are following the ethos of the company and that clients receive the high standard of service at all times, and pushing GMS to grow.


Carl Ollerton

Technical Director

Carl started off his career as a Mechanical Services Engineer before joining GMS Services in 2004

He originally joined as a Contracts Manager before becoming our Technical Director.

As Technical Director, Carl provides all our staff with technical training as well as keeping GMS up to date to current guidance, regulations and legislation.

Carl has over 20 years’ experience in the water industry with a strong mechanical background and a proven track record for delivering works to a high standard.

Carl has helped the business grow rapidly with his high standards of customer service and knowledge of the water industry which he passes onto our customers, clients and our staff whenever they require advice.


Craig Jenkinson

Mechanical Operations Supervisor

Craig started his career as an apprentice plumbing and heating engineer with GMS Services Ltd. Craig now leads the Mechanical Division at GMS. Craig has vast mechanical and water hygiene knowledge, with over 14 years’ experience in the water industry and a strong knowledge of current regulations and guidance.

Craig prides himself with the quality of the installations he has carried out and expects the same from the staff under his supervision.


Stephen Parry

Legionella Operations Supervisor

Stephen first joined GMS in 2007. His experience of Legionella Control & Surveying has helped GMS to grow over the last few years.

Stephen is responsible for overseeing all of our Legionella Risk Assessment programmes and Legionella Monitoring works. Stephen always has new ideas and ways to help GMS provide the best possible service to our clients.


Cath Dahl

Admin Supervisor

After 13 years in sales, Cath joined the GMS team in 2007 initially to audit and coordinate the legionella reports. Since then, Cath has taken the role of Office Manager overseeing various administrative duties which is essential to the day to day organising and planning of the Company.

Cath is an essential part of the management structure at GMS and provides daily support and assistance to all staff and clients who work for and with GMS.

Find out how we can help you!

With our extensive experience in Legionella Risk Assessment Services & Water Treatment Services Contact us today to find out how we can help you.

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LCL Awards Training Centre Achieved

After COVID restrictions put barriers in our way in 2020, we have now reached our goal to become an accredited training centre. This week we officially became an LCL Awards Training Centre. We will initially be providing Water Regulations with a view to providing Unvented Hot Water Training and a Legionella Operators and Managers Course…. Read more »


This weekend (27th February 2021) we have carried out a clean and disinfection of the water system at Melwood Training Ground (Former LFC). The property was purchased by TORUS HOMES last year and is set to open up as a temporary vaccination centre prior to the site being redeveloped as housing in the future. As… Read more »