Natural Hazards

Natural hazards include risks such as flooding, slope instability, erosion, or subsidence. Development should be appropriately designed or limited where natural hazards exist in the region to avoid risks to people, property, infrastructure, and the environment. Preventing risk is more effective than responding after an event or damage has occurred.

Objectives

5-1          Prevent injury and loss of life, and minimize the potential for property damage within areas with potential for flooding

5-2          Avoid or minimize potential impacts of slope instability and subsidence on development, services, and infrastructure

5-3          Avoid development where there is the potential to cause erosion or increase the potential for erosion or slope instability

Policies

General

5.01         Identification of Hazard Lands. Municipalities should identify and map hazard lands within the Region.

5.02         Subdivision and Development on Hazard Lands. Subdivision and development shall not be permitted on hazard lands unless mitigation of the hazard is proven to the satisfaction of the municipality.

Unstable Areas

5.03         Identification of Subsidence Risks. Development applications in areas subject to mining leases shall require consultation with mining companies with local operations as well as appropriate provincial agencies to identify potential subsidence risks.

5.04         Geotechnical Report Required for Development in Unstable Areas. When considering a proposal for rezoning, subdivision, development or redevelopment on lands that may be prone to slumping, subsidence, landslides, erosion or any other instability, the municipality shall require the proponent to prepare and submit a geotechnical report assessing all pertinent hydrological, geological, and other natural or built conditions on site, and any proposed measures that would avoid and/or mitigate hazards. This report shall be prepared by a professional engineer with the appropriate specialization licensed to practice in the Province of Saskatchewan, and shall demonstrate to the satisfaction of the municipality that the proposed development may be safely accommodated on the subject property.

5.05         Mitigation Measures for Safety and Protection of Property. A municipality shall require the proponent to implement, at the proponent’s sole expense, any mitigative actions required to ensure the safety of persons and the protection of property for development on hazard lands.

5.06         Renovations and Additions to Existing Structures. Applications for the redevelopment of or additions to structures in hazard areas identified within an existing geotechnical investigation shall demonstrate, to the satisfaction of the municipality, that the additional development can be accommodated within the scope of the original investigation.

Flood Plains

5.07         Two-Zone Flood Policy. A two-zone flood management policy shall be utilized where the flood plains for the South Saskatchewan River, Opimihaw Creek, and other watercourses and water bodies are divided into the flood way and the flood fringe for a 1:500 flood or other standard as provided in provincial legislation or regulation.

5.08         Defining Flood Plains. Potential flood plains for the 1:500 flood or other standard as provided in provincial legislation or regulation of the South Saskatchewan River, Opimihaw Creek, and other watercourses and water bodies as required shall be determined based on historical information, in consultation with the Water Security Agency and other provincial agencies, and confirmed through a site-specific legal land survey that includes contour lines provided by the proponent at the time of the proposed development or subdivision.

5.09         Coordination of Flood Plain Mapping. P4G shall coordinate with the province to provide mapping of the 1:500 flood or other standard as provided in provincial legislation or regulation for the Region.

5.10         Flood Plain Maps. The flood plain maps included in the Appendix identify the flood plains within the previous Corman Park-Saskatoon Planning District, and shall be used for information prior to full mapping of the 1:500 flood or other standard as provided in provincial legislation or regulation in the Region. Flood plain policies shall not be limited to the areas identified by the attached maps and may be applied to areas deemed to be susceptible to regular flooding based upon historical data, high water marks, photographs of past flooding and in consultation with the Water Security Agency.

5.11         Restricted Development in Flood Plains. Development will be restricted in flood plains to protect against loss of life and to minimize property damage associated with flooding events.

5.12         Land Uses within a Flood Way. Except as otherwise provided for in the policies contained herein, the use of land within a flood way shall be prohibited, except for agricultural and passive open space uses.

5.13         Subdivision within a Flood Way. The subdivision of land for non-agricultural purposes within a flood way shall be prohibited.

5.14         Types of New Development Prohibited within a Flood Way. Dwellings, commercial or industrial buildings, or any building intended for public occupation or for the storage of materials vulnerable to damage by flood waters, and including structures where agricultural products are processed, treated, or packaged shall be prohibited in the flood way.

5.15         Development Agreement Required for Subdivision within a Flood Plain. Applicants for the subdivision of lands within a flood plain shall be required to enter into an agreement with the municipality acknowledging the terms of the approval including, but not limited to, requirements for flood proofing.

5.16         Limited Development within a Flood Fringe. Where development may be permitted in a flood fringe:

a.   the proposed construction shall not obstruct or divert the flow of water; and

b.   the structure shall meet the requirements of proper flood proofing and can withstand the hydrostatic and hydrodynamic effects of flood waters at the 1:500 flood or other standard as provided in provincial legislation or regulation without experiencing damage, as demonstrated in a report prepared by a professional engineer licensed to practice in the Province of Saskatchewan.

5.17         Requirements for Flood Proofing in the Flood Fringe. Where development may be permitted, flood proofing in the flood fringe shall be required to an elevation 0.5 metres above the 1:500 flood or other standard as provided in provincial legislation or regulation of the South Saskatchewan River, Opimihaw Creek, and other watercourses and water bodies as required for:

a.   public buildings and structures;

b.   dwellings;

c.   commercial and industrial buildings;

d.   septic tanks;

e.   well heads;

f.    buildings and structures containing regulated amounts of chemicals, including petroleum storage;

g.   lagoons and liquid waste management systems;

h.   intensive livestock waste disposal facilities;

i.    accessory buildings (attached and detached); and

j.    structures where agricultural products are processed, treated, or packaged.

5.18         Two-Stage Building Permit Process. Every application for a permit to construct, erect, place, alter, repair, renovate, relocate or reconstruct a building or structure subject to flood proofing shall require a two-stage permit to ensure that the building or structure is designed and constructed to meet safe building elevations.

5.19         Flood Proofing Techniques. Every building or structure subject to flood proofing requirements shall be constructed on a site raised by fill; be raised by piles; implement an alternative flood proofing technique deemed acceptable to the municipality; or a combination thereof.

5.20         Certification of Flood Proofing Techniques. All proposed flood proofing shall be designed and certified by a professional engineer licensed to practice in the Province of Saskatchewan. The submission of the design shall be accompanied by a written report identifying the limitations to the design, expected lifespan, and required maintenance.

5.21         Flood Proofing and Elevation Requirements. Every building or structure subject to flood proofing shall have all well heads, liquid waste disposal systems, mechanical or electrical systems, windows, exterior doors, or other exterior openings, located at or above the design flood elevation unless they are part of an approved alternative floodproofing technique.

5.22         Development Agreements for Flood Proofing. As a condition of approval for the construction, erection, placement, alteration, repair, renovation, relocation, or reconstruction of a building or structure subject to flood proofing, the applicant shall be required to enter into an agreement with the municipality acknowledging the terms of the approval including any reporting and maintenance requirements deemed necessary by the municipality.

5.23         Flood Proofing for Existing Buildings and Structures. Existing buildings and structures that do not conform to the flood proofing requirements in this section may continue to be used. Structural repairs, alterations and additions to existing buildings must conform to flood proofing requirements.