The City of Ottawa wants to rezone St. Joseph Blvd. to allow 9-12 storey buildings.

HOWEVER, St. Joseph Blvd. is located on a plateau bisecting an escarpment in Orleans where very reputable scientists have shown it to consist of a deep layer of dangerous Leda clay that is vulnerable to liquefaction and slides, especially in earthquakes. Orleans is an “Extreme” Earthquake Hazard Zone.

The “Quick” Leda Marine Clay is subject to sliding, especially if loaded with weight - as would be the case if the City allows medium-high rise buildings to be built. The Geological Survey of Canada clarifies that there is currently No landslide safety criteria in Canada.  The Canadian Foundation Engineering Manual (CGS, 2006) emphasizes that it is best to avoid building in a landside area or potential landside area. Thus, an immediate moratorium on ANY construction in the area is required until this issue can be satisfactorily studied and all of the residents of Orleans adequately protected with RESTRICTIVE ZONING!

The potential for loss of life and damage to property is very real. It is imperative that NO multi-storey buildings be built along St. Joseph Blvd.

In the St. Joseph Boulevard Arterial Mainstreet Zoning Review:

1.       Create a new zone along ALL of ST. Joseph Blvd that sits on LEDA clay and is on or near City designated ‘UNSTABLE LANDS.’

2.       This new zone would be Restrictive Zoning (2 storey high or less, parking garage location, etc…) designed to limit the loading on the sensitive clay that underlies St. Joseph Blvd. and disturbing its surrounding properties/soils

3.       The zoning needs to go further and permanently entrench setbacks from the unstable slopes

4.       Clarification is needed for City Staff that schedule K is applied to the entire escarpment so that all City staff applies it consistently.  

5.       In the meantime, an immediate moratorium on ANY construction in the area is required until this issue can be satisfactorily studied and all of the residents of Orleans adequately protected.

6.       This microzone requires further study in light of new research, and City engineers must review

      1.     LANDSLIDE RISK EVALUATION,Canadian Technical Guidelines and Best Practices related to Landslides: a national initiative for loss reduction,GEOLOGICAL SURVEY OF CANADA OPEN FILE 7312  M. Porter and N. Morgenstern, p.16., 2013

      2.       Hunter, Motezedian. 2008. Development of an NEHRP map for the Orleans suburb of Ottawa, Ontario. Can Geotech J. Vol. 45: 1180-1188 (2008), NRC Canada

      3.       Earthquake Hazard Zones: The relative risk of damage to Canadian buildings, Paul Kovaks & Robert Sweeting, Institute for Catastrophic Loss Reduction, University of Western Ontario, 2004, www.iclr.org/images/Earthquake_Hazard_Zones.pdf

The City needs to develop a comprehensive policy to protect its citizens from a Landslide or sinkhole disaster. Similar to Ottawa’s policy 4.8.1 on Flood Plains that does a much better job of recognizing widespread catastrophe and restricting development accordingly.