1      Scope

1.1     General

This Guideline covers measures to reduce the risks of basement flooding, and to mitigate the adverse effects on property, public safety, and public health in case of a flood event. It covers existing, new, rebuilt, and renovated houses in rural and urban settings.

1.2 Buildings covered

This Guideline covers all types of ground-related houses, with or without basements, that are considered Part 9 buildings according to the National Building Code (NBC) including

a) detached houses;

b) semi-detached houses; and

c) row houses.

Recommendations made in this Guideline are generally appropriate for houses serviced by gravity-based storm, sanitary, combined, or third pipe systems.

1.3 Types of flood hazards[JL1] [CC2] [CC3] 

The types of flood hazards addressed by the measures described in this Guideline are

a) overland flooding associated with precipitation events  and resulting in the accumulation/ponding of rainwater and/or snow melt in and around ground-related houses;

b) storm and sanitary sewer backwater (surcharge);

c) infiltration flooding (groundwater seepage);

d) plumbing and drainage failures, including failure of sump systems and sewer lateral failure; and

e) flooding associated with improper installation of basement flood risk-reduction technologies (see Annex A).

Note: Users of this Guideline are reminded that any of the provisions outlined herein are subject to existing codes and standards that are applicable in the jurisdiction under which the Guideline user is operating. It is strongly recommended that appropriate licensed professionals conduct any work outlined in this Guideline. All appropriate local, provincial, and national codes and standards must be adhered to in the application of the provisions outlined herein. All appropriate permits and inspections from authorities having jurisdiction must be obtained when undertaking any of the work outlined here.

1.4 Exclusions

While the measures presented in this Guideline might limit some types of flood risks to a degree, this Guideline is not meant to address riverine and coastal flood (inclusive of large water bodies) risks.

Note: Further information on Engineering for floor resistance is available through NRCs Guide for Flood Resistant Buildings.