Part 4 – Stormwater Drainage

4.22    Subsoil Drainage

Subsoil drainage shall be designed as private drainage so that it does not result in increased run-off, erosion and sedimentation on neighbouring properties.

Note:  Sub-soil drainage is subject to approval under the Building Act 2004.  Building Consents shall be obtained before commencement of site work.

To prevent instability of the local ground, the design should ensure that no fine soil particles are transported into the stormwater system through the subsoil drainage.

Any subsoil drainage design must consider the effects on groundwater, particularly in peat areas where water level reduction is not permitted without prior Council approval.