Parts of Surrey, Kent and south London
SES Water: water quality and hardness
SES Water supplies drinking water in parts of Surrey, Kent and south London. The precise supply zone matters more than the broad regional description when choosing a local report.
An independent WaterGrade guide. Local readings vary by source area and date.
Find the water serving your home
Use the supplier’s official postcode or area-report route to identify your zone, then find any verified records we hold below.
Find my official local report ↗Automated WaterGrade postcode matching is not yet available for this supplier.
How SES Water reports on your water
SES publishes postcode-based quality and hardness reports. Its hardness guidance explains that some sources are partially softened during treatment, while other sources are naturally softer; a general chalk-groundwater assumption is therefore insufficient.
Use the current postcode report and read any operational notes alongside the annual hardness table. Check whether the unit refers to calcium or calcium carbonate before converting it for your dishwasher.
Company information and source context ↗What WaterGrade currently holds
Local measurements from SES Water have not yet been imported and approved. This page explains its report tools and helps you interpret the original data; no hardness number or quality score is inferred.
Is the water hard or soft?
Check the figure for your supply zone. A company can deliver water from different sources, so a single average can give the wrong appliance setting for your home. Hardness describes dissolved minerals; it is not a safety rating.
Our local cards use mg/l as calcium carbonate (CaCO₃). Keep the original unit and reporting period when comparing results. Supplier labels can use different hardness bands.
What do the quality results tell you?
Read each parameter with its units, sample count, range and reporting period. A mean below a reference limit does not establish that every sample complied. A “less than” result is not an exact concentration.
Company-wide performance, local zone results and water at an individual tap are different levels of information. Historical exceedances need the supplier’s investigation context; they are not automatically a current incident.
Understand the measurements in a water reportFind your local source-area report
Use the exact area name from the supplier’s checker. Older areas can have been renamed or replaced. Each card keeps the hardness period separate from other quality data.
Start with the supplier’s original report
- Open the official quality route and find your postcode or supply zone.
- Note the reporting period, hardness unit and any explanation of changes.
- Use our converter and report guide to interpret it. Report an unclear or missing source to WaterGrade.
Has the water changed over time?
Compare the same named area, metric, units and kind of reporting period. A new download date is not a new sample. Renamed zones or overlapping rolling windows need extra care before drawing a trend.
We do not yet hold a comparable annual hardness series for this supplier. We do not draw a trend from a single edition or overlapping rolling reports.
Open a local report and choose “Save on this browser” to return later. Saved reports can be checked for revised published details; this is not an emergency-alert service.
Official help and sources
For a new change in water appearance, taste, smell or supply, check the supplier’s current guidance and contact it directly. This page summarises published information and does not monitor live incidents.
Company guide and official routes reviewed 6 September 2026. Measurements refresh from approved reports and retain their own dates. Read our source methodology.
← Explore another water company