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What Can You Expect When Your Water Retailer Submits A Service Request (A Bilateral) To A Water Wholesaler On Your Behalf?

John Reynolds, Castle Water CEO, looks at what you can expect when your water retailer submits a service request (a Bilateral) to a water Wholesaler.

There are a range of activities that we, at Castle Water, carry out for our customers, for example repairing or replacing a meter, or requesting a leak allowance, where we need the Wholesaler (who owns the water network) to carry out work or change data recorded in the central market systems (CMS).

This is done by Castle Water submitting a “Bilateral” form on your behalf – a Bilateral is a formal service request in a prescribed format. In 2019, we submitted nearly 23,000 Bilateral forms on behalf of customers. If we submit a bilateral form on your behalf, this article summarises what you can expect.

The water market is governed by a set of Codes which set out the respective responsibilities of Wholesaler e.g Thames Water and Retailer e.g Castle Water. The Codes are a commercial contract between Wholesalers and Retailers which set out both responsibilities and processes in line by line detail.

These include the processes and forms for all usual market data and charging changes (confusingly referred to as Transactions, which they aren’t). Because Castle Water pays all charges on your behalf, if something is wrong we are as keen as you are to correct it.

Meters and Meter Reading

The Wholesaler owns and is responsible for maintaining water meters, and for ensuring that meter data is correct. If there is a fault with a meter, or meter-related data is incorrect, we will request that the Wholesaler investigates and takes appropriate remedial action. Your current bill will be valid until any updates have been made to the CMS by the Wholesaler, and this data is used to charge us as a Retailer for your water services, which we pay on your behalf.

Although the Wholesaler owns and maintains the meters, they are not responsible for taking meter readings. Meter readings can be taken by either the Retailer or the Customer and used for billing. Customers can submit meter readings to Castle Water at any time, which may be used to calculate your next bill. Meter readings can be submitted at our meter reading page . The Wholesaler is also responsible for determining the charges payable for your premises, deciding whether there is a meter and what it should serve, or if there is no meter, how the quantity of water supplied should be assessed. Their responsibilities in this area are made clear in the Market Codes and in each Wholesaler’s Wholesale Tariff Document.

Where you receive separate bills for water and waste services, only the water retailer can enter and amend meter details, including meter readings- even though the meter readings are used to determine waste charges as well as water.

If your water meter is on your own land, you should keep it accessible and free of debris so it can be read. If you rely on meter readings to monitor your own consumption, it can be a good idea to take readings monthly, as sometimes we are unable to take meter readings for reasons outside our control – for example, because of a vehicle parked over a meter pit (and please share meter readings with us via our website).

How Charges are Calculated

Charges are based on the supply configuration at each specific site. The data items which determine charges are the responsibility of the Wholesaler (with the exception of meter readings). The Wholesaler has a duty to ensure that these are accurate.

Updating Data and Charges

Where we are asked by a customer to amend charging details or request repairs which are the responsibility of the Wholesaler, we submit a specific Bilateral form, normally via the Wholesaler’s portal, which is only available to licensed water retailers. Bilaterals are only accepted from the current retailer to any specific site – if you transfer to a different retailer, only that retailer can submit bilateral forms, including in relation to prior periods.

The Wholesaler may call you to arrange a time to survey or carry out work at your premises. If you think you may have missed a call from the Wholesaler, please let us know as soon as you can. When they have investigated or completed the work, the Wholesaler will let Castle Water know and we will share their update and decision with you and tell you how it will impact your charges, if at all.

Service Levels

The Wholesaler has an obligation under the Codes to complete the action within a defined SLA, although these are not always met. SLAs in respect of some of the most common requests are:

  • Perform a meter accuracy test: 10 business days
  • Repair a meter: 22 business days
  • Verify meter supply arrangements: 10 business days
  • Deregistration of a Supply Point: 20 business days
  • Application for a Leak Allowance: 20 business days

In some more complex cases, 2 separate Bilaterals may be required to complete corrections to the market data. For example, we might need to request the Wholesaler to check supply arrangements, and then they may delay making any repairs, in which case we could make an additional request to install a new meter. This would be counted as two separate requests, with their own SLAs.

In practice, many SLAs are not met by Wholesalers. During 2019, we found that SLAs were met only in around 44% of cases. Unfortunately, we have no effective way to resolve these – although we actively monitor Wholesaler completion of Bilaterals, and can escalate issues where we are concerned about delays.

What isn’t covered by Bilaterals

Although there are 23 different forms for different service requests, these do not cover insurance claims or a new connection or changes to existing supply arrangements – if you want a new connection to be provided by your Wholesaler, you will need to contact their Developer Services department and discuss your requirements with them. Likewise, insurance claims, for example for damage caused by a Wholesaler, can’t be dealt with via a Retailer – you will need to contact the Wholesaler directly.

Enforcing the Codes

As a retailer, Castle Water has few rights to force other parties to comply with the Codes and has no step-in rights if a Wholesaler does not meet its obligations. We are trying to change things to give step-in rights where necessary, and have proposed this to the Panel. The Codes can be enforced by the Panel, and also by Ofwat (compliance with the Codes is a licence obligation).

The Panel

The Codes Panel has responsibility for ensuring compliance with the Codes. Customers are represented at the Panel by the Consumer Council for Water. As a member of the Panel, CCWater is able to propose Codes changes on behalf of customers. Castle Water has made a number of change proposals, aimed at making the market simpler and fairer.

Our experience is that changes to the Codes are difficult to push through, even where they seem to be in everyone’s interests. All Panel meetings are public, and the Panel secretariat arranges a dial-in facility to join the meetings. As a Customer, you are able to directly observe the governance of the market! You can contact the Panel secretariat at

According to the MOSL website:

The introduction of competition in water and wastewater retail services aims to increase efficiency, drive down prices and improve customer service.

The Panel supports these goals by providing independent strategic governance of the market. It keeps the market codes under review, making sure that they are operating effectively and that they evolve in a way that:

  • Improves the efficiency and effectiveness of the market
  • Promotes competition
  • Benefits end customers
  • Makes regulatory intervention a last resort

How we help

Everyone at Castle Water works hard to ensure that all our customers are charged the right amount for provision of a safe, clean water supply. Because we submit so many Bilaterals and have a detailed knowledge of the obligations on Wholesalers, we are normally in a good position to get the right outcome for you.