A pressure test confirms that a section of new or repaired drainage is watertight by sealing the line, filling it with water or air and monitoring for loss against an acceptance criterion. Water tests are typically carried out on gravity drains under BS EN 1610 with a head pressure of 1.0 metre and a defined permissible loss over a fixed time. Air tests are used where water access is difficult, working to lower pressures specified in the same standard. The method is essential for sign-off of new drainage installations, repairs and adoption agreements with Thames Water under Sewers for Adoption guidance. Engineers carry out the test in accordance with industry practice using calibrated gauges and provide a written record. Results inform any required remedial action before the line is brought into service.
Pressure test (drain)
Hydraulic test that pressurises a drain section to confirm watertightness against a standard.
