Slope Stability Management

Unstable cliffside

Medicine Hat is built around a river valley and there are several coulees and creeks within the city boundary. There are some slopes that are considered unstable.

Certain land features can indicate problems with slope stability, including tension cracks, localized slumping, slope surface erosion, bank erosion or scour, or shallow or deep seated slope failures. Unstable slopes, as well as slopes that have been repaired, are monitored by City engineering staff on a regular basis.

If your property is situated near a coulee slope or otherwise on very sloped land, slope management is important to minimize failure. Land owners are responsible for addressing slope stability concerns on their own land and for taking measures to mitigate or eliminate risks to people and land.

Slope Setback Assessment

Know the rules for your lot

If you own a property which has such a development setback boundary on it, there are things you should be aware of:

  • The location of the setback line does not have any immediate impact on your property.
  • There are no existing safety concerns associated with ownership or occupancy.
  • It is important to contact Planning & Development Services before doing any new projects on your property (fence, shed, deck, retaining wall, pond, grading, etc.)

View slope setbacks

There is a slope setback for development established by the City in order to help prevent human activity from causing or advancing potential slope failures. This means that any development (buildings, ponds, sheds, retaining walls etc.) must not occur past this line, which is too near the top of the bank.

You must adhere to all geotechnical recommendations which apply to your lot. Also, you must not alter or deviate from approved grading or drainage plans. If you do not know where this slope setback line is on your property, or you have any other questions about slope stability, contact us.

How to use iMap

How to use City iMap for Slope Management

Tips for management

Plan your landscaping

Human activities such as landscaping can further destabilize slopes.  TIPS:

  • Maintain natural vegetation on the coulee slope itself. The root structures of natural vegetation help to stabilize the earth.
  • Before building a retaining wall, check with an engineering staff member at Planning & Development Services (contact info above). 
  • Locate yard waste and other material away from the top of bank. This will help to maintain the health of the natural stabilizing vegetation. Better yet, use a compost bin!
  • See Backyard Composting - It's Only Natural (PDF)
  • Locate pools, hot tubs, ponds etc. away from the top of bank. 
  • Seek professional advice for lot grading, landscaping or construction activities.

Be water smart

  • Excessive irrigation (infiltration) is a leading cause of slope failure on private properties in Medicine Hat.
  • Do not irrigate beyond the setback line. Utilize drought-tolerant landscaping to minimize the amount of watering required.
  • In front of the setback line, water your lawn for shorter time periods with more frequent cycles. For example, water for 5 minutes in 3 cycles separated by 30 minutes in between, instead of 1 cycle for 15 minutes. Better yet, try xeriscaping!
  • Try water-efficient landscaping.
  • Do not direct roof drainage (downspouts) toward the slope. Direct the drainage elsewhere, or capture the runoff and drain it though a pipe to the toe of the slope.
  • Learn more about roof drainage by visiting basement water.

Keep an eye on it

  • Do regular inspections of your property.
  • Make sure that existing retaining walls are in good repair.
  • Make sure that existing water sources (ponds, hot tubs, irrigation lines etc.) are free of leaks.
  • On the slope, check any trees for tilting or bending, which is a sign of slope slumping.
  • Work together with neighbours to help minimize slope instabilities.

Slope failure

Private land

It is the property owner's responsibility to mitigate or repair slope stability issues and/or damage, whether the issues are the result of natural processes or the actions of the landowner. If a failing slope has created a safety concern, the City may issue orders against the owner to ensure that the property is secured and returned to a safe condition.

If your property is experiencing a slope failure, ask to speak with an engineering staff member at Planning & Development Services. The City will investigate slope stability concerns on private property and may offer suggestions. However, the City will not make direct recommendations or design solutions for issues on private land. Land owners should seek the advice of qualified professionals for recommendations or designs.

City land

If a slope on City land is deemed to have a likelihood of failure and will cause damage to City infrastructure (trails, roads, structures, etc.) the slope will be identified for repair. After public safety is ensured, an engineering consultant will likely be hired by The City to investigate the cause of the slope failure and to recommend solutions. Then, measures can be taken to repair and/or mitigate the situation.