Slopes and Unstable Terrain

Steep slopes are not generally a good place for development.  For one thing, soil, plants and anything else attached to the slopes may not be very stable.  A landslide can cause not only environment problems but economic inconvenience, damage to property and even harm to humans. 

General

As a general rule a property owner only has the right to make use of his or her property in a way that does not negatively affect the rights of others.  Consequently, if changes to a property result in landslides or the settling of otherwise stable terrain on a neighbour’s property, the neighbour may be entitled to sue, claiming compensation; in some extreme cases it may even be possible to get an order preventing the changes from being made at all.  Similarly, changes to unstable slopes affecting other rights might form the basis of a law suit.  However, this can be an expensive and difficult process.  See the Guide page on private common law rights for more information. 

Terrain stability may also be considered in respect of larger projects (whether on private or public land) that are required to do an environmental assessment, under either the B.C. Environmental Assessment Act or the Canadian Environmental Assessment Act. 

Terrain stability issues related to rivers and other water-courses are dealt with under the Dike Maintenance Act as well as on legislation and planning processes more generally related to watercourses and riparian (bank) areas.

Private Land

Development that might cause landslides can be regulated in a few different ways on private land.  First, the stability of private land should be taken into account before a subdivision application is approved under the Land Title Act (ie. when a larger property is broken into smaller units of property, usually to be developed or sold). 

Second, a Local Government may pass laws that restrict the right of a property owner to use their lands, thereby directly or indirectly limiting development on lands that may be unstable.  Tools include:

·         Zoning-bylaws limiting lot-size or type of development in areas with unstable terrain; and

·         A by-law or Official Community Plan that identifies Development Permit Areas where there are terrain stability issues and for which a special development permit will be required. 

·         Terrain stability and water flow may be considered as an application for a building permit.

Talk to your municipality or regional district to find out what mechanisms are in place to prevent development on unstable terrain.

Public Land

The legal tools that protect against development on unstable terrain on private land do not apply to land owned by the province.  Most development activities that might increase the likelihood of landslides or other terrain stability problems are governed by particular statutes.  For example, the Forest Practices Code has results related to terrain stability, as well as providing for special land use designations where more detailed planning for terrain stability must be carried out. 

Related Guide Pages:

·         Local Government – Development Permit Areas

·         Forest Practices Code – Land Designations

For more information about Slopes and Unstable Terrain:

·         Measures for Control and Management of Unstable Terrain, by S. Chatwin of the B.C. Ministry of Forests.

·         Discriminating between Landslide Sites and Potentially Unstable Terrain using Topographical Variables – A very technical paper by J. Appt and others of the Department of Forest Engineering, Oregon State University.