Introducing a new kind of water and wastewater network operator, providing you with a dedicated service, tailored specifically to you.
By choosing Castle Water, you are choosing more than a water network operator – you are opting for a partner that provides unmatched control, care, and efficiency in water and wastewater management.
We are now introducing our services as a water and wastewater network owner in order to provide our customers with:
We believe it’s critical to get it right, first time, every time.
Castle Water Networks Ltd has applied for an appointment replacing Thames Water Limited as a relevant water and sewerage undertaker for: The Peninsula Hotel, London
Castle Water Networks Ltd has applied for an appointment replacing Yorkshire Water as a relevant water and sewerage undertaker for;
Frenchgate Shopping Centre
Castle Water is the largest independent water retailer in England and Scotland, with 20% market share in the non-household water retail market. Castle Water was the first independent water retailer in England and is the only Water Retailer to obtain a Wholesale Authorisation License.
customers
supply points
5-star reviews
A NAV, or New Appointment and Variation, is a licence granted by Ofwat allowing a company other than the regional water or sewerage company to provide water and/or wastewater services to a specific site. NAVs are increasingly used by developers, commercial property owners, and large multi-site businesses looking for more responsive, tailored and cost-effective alternatives.
Castle Water is an experienced network operator and licensed retailer, able to take ownership of the water and wastewater infrastructure and provide regulated services under a NAV agreement.
We’re more than just a retailer — we’re your network partner. Our NAV and network operator offering provides a new kind of service model in the UK water market:
✅ Dedicated Account Management
Work directly with experts who understand your site’s infrastructure, needs and business goals.
✅ Regulatory Compliance Made Easy
We manage all regulatory obligations, reporting, and liaising with Ofwat and other authorities on your behalf.
✅ Rapid Response to Network Issues
Get quicker issue resolution and ongoing support from a partner with industry-leading customer service.
✅ Tailored Solutions
From bespoke tariffs to multi-site billing consolidation, we’ll design a network solution that works for your business or development.
✅ Environmental Accountability
We support water efficiency, leak detection, and sustainable network management — helping you meet ESG goals.
Skip to content
