3.01. Group of buildings: A system for the discharge, collection or disposal of domestic waste water, grey water or toilet effluents referred to in this Regulation must serve only one building or only one site referred to in section 2, except in the following cases:
(a) the system serves a group of buildings situated on the same immovable, consisting of an isolated dwelling and its accessory building, to the extent that the total daily flow from the group is not more than 3,240 litres;
(b) the system serves any of the following groups of buildings:
i. two isolated dwellings, to the extent that the number of bedrooms for the group is equal to or fewer than 6;
ii. one isolated dwelling and one building other than an isolated dwelling, to the extent that the total daily flow of domestic waste water for the group is not more than 3,240 litres, considering, for the purposes of the calculation, a daily unit flow of 540 litres per bedroom;
iii. two buildings other than an isolated dwelling, to the extent that the total daily flow of domestic waste water for the group is not more than 3,240 litres.
A group referred to in subparagraph b of the first paragraph is possible only where the conditions of the sites and natural land require the installation of a tertiary treatment system with phosphorous removal or a tertiary treatment system with phosphorous removal and disinfection.
306-2017O.C. 306-2017, s. 71; 1156-2020O.C. 1156-2020, s. 911.