Technical Booklet N Drainage·Page 8·7(2)
Cesspool construction requirements
A cesspool must be of suitable depth for complete emptying, impervious to surface water, fitted with a manhole cover, adequately ventilated, have no overflow outlets, and have a minimum capacity of 18 m³ below the inlet level.
A cesspool shall be—
(a) of suitable depth to enable it to be emptied completely;
(b) properly covered so as to be impervious to surface water and rainwater;
(c) fitted with a suitable manhole cover for the purposes of inspection (including inspection of the inlet), emptying and cleansing;
(d) adequately ventilated;
(e) without any outlet for overflow or discharge other than the outlet provided for emptying or cleansing; and
(f) of a capacity, measured below the level of the inlet, of not less than 18 m³.
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