Water treatment and engineering for industry and the public sector

Protecting occupational health and delivery of safe, ‘pure’ water

Outstanding water treatment process, control and improvement

Water Treatment & Hygiene

The H2O experts. Quality water treatment, system control and Legionella compliance for industry and the public sector.

WCS Group and Guardian Water Treatment are brands forming the water division of Marlowe Critical Services. Water control improvement, Legionella risk management and hygiene experts, we provide water systems and process knowledge, life cycle and asset management, Legionella control and training which helps customers optimise their systems whilst reducing energy and water usage safely and reliably.

We ensure compliance with ACoP L8, cooling tower and evaporative condenser regulations, HTM04-01, closed heating & chilled systems guidelines and swimming pool guidelines, environmental standards including water discharge and Regional Protection Zones.

Services provided:


  • Water systems design, build, monitor, maintain
  • Closed System improvement & problem solving
  • Audit, test, monitor, service
  • Chemical management, dosing & delivery
  • Operational improvement engineering
  • Re-purposing water, purification, effluent management
  • Training and ACoP L8 compliance

Our Companies

National coverage, local service

Over 320 water experts provide a local service through regional teams and offices across the country with deep sector experience.

Water treatment specialist, L8 Legionella control overview

Download our water overview to learn about better water treatment solutions, exacting Legionella control, reducing water and chemical use, re-use of water, ensuring enhanced site and operating safety, compliance and our accreditation check list.

Rapid Enquiry Water Treatment Website