78.—(1) Regulation 82 shall not apply to a drainage system intended for use in connection with a roof or balcony of 6 m2 or less in area, unless that roof or balcony receives a flow of rainwater from another part of a building.
(2) In this Part—
“Foul water” means waste from a sanitary appliance and water which has been used for cooking or washing purposes and not contaminated by trade effluent;
“Rainwater drainage” includes gutters, pipes, drains and fittings which convey rainwater only;
“Sanitary appliance” has the meaning assigned to it by regulation 84 in Part P;
“Sanitary pipework” means a pipe or system of pipes for conveying foul water from a fitting to an underground foul drain; and
“Underground foul drainage” includes drains and private sewers used in connection with buildings but not a system which is solely for the conveyance of subsurface water.
79. Every building shall be provided with such sanitary pipework, underground foul drainage and rainwater drainage as may be necessary for the hygienic and adequate disposal of foul water and rainwater from that building.
80. Sanitary pipework shall—
(a)consist of pipes and fittings—
(i)of such size, layout, construction and watertightness; and
(ii)with sufficient ventilation,
to ensure the hygienic conveyance of foul water to an underground foul drainage system; and
(b)have such means of access as is necessary to facilitate the clearance of blockages.
81. Underground foul drainage shall—
(a)consist of pipes and fittings—
(i)of such size, layout, construction and watertightness; and
(ii)with sufficient ventilation,
to ensure the hygienic conveyance of foul water to a sewer, cesspool, septic tank or similar structure; and
(b)have such means of access as is necessary to facilitate the clearance of blockages.
82. Rainwater drainage shall—
(a)consist of pipes and fittings—
(i)of such size, layout, construction and watertightness; and
(ii)with sufficient ventilation,
to ensure the hygienic conveyance of rainwater to a surface water or combined sewer, a soakaway or a watercourse; and
(b)have such means of access as is necessary to facilitate the clearance of blockages.
83.—(1) Any cesspool, septic tank or similar structure shall be—
(a)so constructed as to be impervious to both liquid from the inside and subsoil water from the outside; and
(b)so sited—
(i)as not to render liable to pollution any spring, stream, well, adit or other source of water which is used, or is likely to be used, for drinking, domestic or kitchen purposes;
(ii)that there is ready means of access for cleansing it and removing its contents without carrying them through any building in which any person resides or is employed in any manufacture, trade or business, or to which the public has access; and
(iii)as not to be in such proximity to any building in which any person resides or is employed in any manufacture, trade or business, or to which the public has access, as to be liable to become a source of nuisance or a danger to health.
(2) 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.
(3) Any structure to which paragraph (1) applies other than a cesspool shall be—
(a)of suitable depth;
(b)of adequate size, having in no case a capacity of less than 2.7 m3;
(c)covered or fenced in;
(d)if covered, adequately ventilated and constructed with means of access for the purposes of inspection (including inspection of the inlet and outlet), emptying and cleansing; and
(e)fitted with filter or other treatment facility for effluent (including subsurface irrigation) or both, sited to comply with the requirements of paragraph (1)(b)(i) and (iii).