A service condition grade reflects the impact of observed defects on the day-to-day operation of a drain or sewer, scored from 1 to 5 under the WRc Manual of Sewer Condition Classification. The grade considers issues such as blockages, root masses, sediment build-up, deformed pipe and other factors that restrict effective flow. A grade 5 service condition typically indicates an active or imminent blockage that warrants urgent clearance and follow-up CCTV inspection. The grading is used by Thames Water, adoption schemes under Sewers for Adoption and private surveyors carrying out CCTV inspections to BS EN 13508-2 across Greater London. The output supports prioritisation of cleansing, maintenance and repair, and provides a clear, consistent way to communicate the operational risk of a drain to homeowners, freeholders and insurers.
Service condition grade (SCRIM)
WRc grade reflecting how a defect affects ongoing service and operation of a drain.
