Plain-English answers about commercial surface water drainage charges, evidence and applications.
Visual examples can help visitors recognise the kinds of sites where a review may be relevant.
Warehouses, factories and depots with large hardstanding areas.
Offices, retail units and mixed-use business sites.
Sites with multiple buildings and shared infrastructure.
Properties where runoff routes can be affected by layout and use.
It is a wastewater charge associated with collecting and dealing with rainwater that runs from a property into the public sewer system. It may appear separately on a bill or form part of another wastewater charging calculation.
A reduction may be available where the required evidence shows that no surface water from the property enters a public sewer. Some site-area charging arrangements may also recognise qualifying areas that drain elsewhere.
No. The provider may need evidence that all relevant surface water avoids the public sewer. Overflows, shared pipes or other connections can affect the decision.
Potentially, depending on the provider's charging scheme and the proportion of the site that drains elsewhere. The bill and site layout need to be reviewed together.
Surface water drainage relates to rainwater from the property. Highway drainage relates to rainwater from public roads and highways. A successful surface water application may not remove other wastewater or highway drainage charges.
Possible evidence includes drainage plans, photographs, downpipe routes, inspection chamber information, site records, dye testing, surveys or a provider inspection. The appropriate evidence depends on the property.
The amount depends on the charging method, site, tariff and provider. The Nantwich example on this website achieved an annual reduction of £1,270, but that outcome is specific to that property and is not a forecast for another case.
Possibly, but backdating policies vary. The provider decides the effective date, evidence standard and any maximum refund period. A historic refund should never be assumed before a decision is issued.
There is no universal timescale. Straightforward cases may be resolved more quickly, while complex sites, missing plans, inspections or provider queries can extend the process.
Yes. The person making an enquiry should explain their relationship to the property. The provider may require authority from the account holder, owner or another responsible party before making changes.
Yes. Customers can approach their water retailer or sewerage company directly. MAW Water Rebate UK offers independent help with reviewing the position, identifying evidence and presenting the information clearly.
No. MAW Water Rebate UK is an independent consultancy and is not affiliated with a water company, retailer, Ofwat, CCW or a government body.
These independent public sources provide further guidance about water charges and consumer support.
Ofwat explains surface water drainage charging and the principle that a reduction may be available where surface water does not enter a public sewer.
CCW is the independent voice for water consumers in England and Wales and provides advice and support with water-company or retailer complaints.
External websites are provided for general information. MAW Water Rebate UK does not control or endorse their content.
Email a recent bill and a brief description of the drainage for a free initial review.
