Q-2, r. 9.01 - Design code of a storm water management system eligible for a declaration of compliance

Section 83 Disposition versions

2020-12-31

83. A minimum distance of 300 mm must separate the groundwater average seasonal peak and the floor of the dry retention system at its lowest point, except if the dry retention system is constituted of a leakproof membrane or perforated drains collecting the water under the system floor.

The groundwater average seasonal peak is determined using one of the following methods:

(1)  the average of the maximum levels recorded between 1 May and 30 November for at least 2 years using a piezometer installed on the site of the dry retention system;

(2)  from the observation of the redox level on the site of the dry retention system;

(3)  by adding 1.5 m to a punctual measurement of the groundwater level obtained on the site of the dry retention system. If the calculation leads to a groundwater level above the surface, the groundwater average seasonal peak is a level flush with the surface.

O.C. 871-2020, s. 83.

Not in force

In force: 2020-12-31

83. A minimum distance of 300 mm must separate the groundwater average seasonal peak and the floor of the dry retention system at its lowest point, except if the dry retention system is constituted of a leakproof membrane or perforated drains collecting the water under the system floor.

The groundwater average seasonal peak is determined using one of the following methods:

(1)  the average of the maximum levels recorded between 1 May and 30 November for at least 2 years using a piezometer installed on the site of the dry retention system;

(2)  from the observation of the redox level on the site of the dry retention system;

(3)  by adding 1.5 m to a punctual measurement of the groundwater level obtained on the site of the dry retention system. If the calculation leads to a groundwater level above the surface, the groundwater average seasonal peak is a level flush with the surface.

O.C. 871-2020, s. 83.