For basic storage and disposal of off-mains waste water.

Cesspit | Cesspool

  • Don’t confuse a Cesspit with a Cesspool.A Cesspit is an underground chamber used for the storage of sewage. The appearance of a cesspit is similar to that of a ‘hand dug’ water well.Cesspit’s were traditionally constructed by digging a cylindrical void into the ground of approximately one metre in diameter, and typically to a depth possible without machinery. The void would be lined with bricks, positioned approximately 2” apart, thus keeping small voids between the bricks. A concrete slab would be positioned on top of the bricks with a manhole access point.cesspit

    The idea of a cesspit was to allow liquid sewage to soak into the ground through the soil base of the cesspit, and gaps between the bricks. The remaining sewage solids would settle and compost in the base of cesspit. This would have the effect of ‘blinding’ the base of the cesspit, preventing any of the liquids from soaking away.

    The use of cesspit’s has not been permissible for some time, due to the significant pollution risks. The Public Health Act of 1936 prohibits their use, but this represents a consolidation of a number of previous Acts. Records show that a Government committee in 1875 stated that this style of cesspit be ‘utterly condemned’ (ref. Sewage Disposal Works, published 1890).

    Cesspit’s should not be confused with Cesspools. Cesspools are sealed, watertight underground tanks designed to simply collect sewage without processing, treating or allowing the sewage to soakaway.


    A Cesspool is merely a holding tank designed for the containment of sewage. Cesspools are typically constructed from fibreglass and are designed to be installed underground. A cesspool has one inlet for the connection of foul drainage and one socket for the connection of a vent. A cesspool doesn’t have an outlet. Therefore, if a soakaway / drainage field is present then an alternative form of sewage tank is installed, most likely a septic tank.

    Cesspools should not be confused with septic tanks. Septic tanks provide partial treatment of sewage and have an outlet which connects to an underground soakaway / drainage field. Click here for further information on septic tanks.

    A Cesspool would require frequent emptying by a Licensed Waste Carrier, and as a result, can cost the owner of the cesspool thousands of pounds per year in emptying charges. A cesspool should only be installed in situations where an alternative waste water disposal method cannot be achieved.

    Cesspool Conversion

    Some cesspools can be ‘converted’ into small sewage treatment systems by installing a Mantair conversion unit. The Mantair unit is designed to fit within an existing cesspool or septic tank, ‘converting’ the existing tank into small sewage treatment system. After installation of the Mantair unit the cesspool tank would only require emptying on an annual basis.

    The treated effluent produced from the Mantair unit is suitable for discharge direct to a natural watercourse, or underground soakaway / drainage field. The Environment Agency recognises the Mantair unit as a sewage treatment system and authorises its use under Permit Certification, allowing the treated effluent from the system to be discharged directly into natural watercourses. Click here for further information on cesspool conversion.

    For further information or advise regarding cesspit’s or cesspools, contact us on (    ) or complete the form below.c applications cesspools should have a capacity below the level of the invert of at least 18,000 Ltrs for two users,and should be increased by 6800 Ltrs for each additional user. Cesspools for commercial premises have no such restrictions.