Low Cost Sewer Monitor for Small Diameter Pipes



Most incidents where customers see their property flood internally are caused by blockages in the first length of the small diameter sewer which serves the property. These sewer lengths are usually 100-150mm in diameter and made of vitrified clay, or occasionally, other materials such as plastic or cast iron.


At the property, the sewer will have multiple connections, usually transferring ‘black’ (toilet) and ‘grey’ (e.g. shower, bath, sink) water through a ‘fall pipe’ from upstairs; an external gully taking rainwater from gutters; and ‘grey’ water (e.g. sinks, washing machines, dishwashers) from downstairs. There will also be a connection to any downstairs toilets and cellar gullies.


Existing sewer level monitors are not suitable for monitoring these small diameter sewers as:


  • They are too large and cannot be fitted in the pipe.
  • The intermittent and variable volume of waste water discharged from a property means continuous monitoring will require a level of intelligence to account for higher variability in flow and level when compared to monitors installed in a network.
  • They are also too expensive (circa £1,500) to enable installation in large quantities.
    In one partner’s region, there are 262,000 cellared properties and around 1,565 properties suffer from internal flooding each year.


The nearest point to the property which can be monitored through the current solutions available is a downstream manhole. However, this leaves an initial length of sewer unmonitored, preventing a proactive approach to avoid/mitigate any incidents.




A low cost, small diameter (100-150mm) sewer level monitor that can (ideally) be installed by a network operator and will successfully support proactive monitoring of the first section of the sewer connecting a property.

Water companies have a limited budget to monitor sewers, therefore, the cheaper the unit, the more units are likely to be deployed.





The closure date for registering initial interest is 07.01.2019. 


To register initial interest and request an ‘expression of interest’ form, please enter your details online. Alternatively, please call the Energy Innovation Centre on 0151 348 8040 and quote the reference number.


Please note: Specific EOI forms are created for each individual ‘Call for Innovation’ and the matching form will be required to progress any submissions. Office open hours are between 9am and 5pm Monday to Friday.