Headlines: The week in review

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1. posted under Alain Miguelez “History of the Ottawa Underground Tunnel” Jan 26 2010. Presently relevant because of earthquake of June 23 2010

   Mr. Miguelez,

   This is the best presentation I have yet read on the historical aspects of a downtown Ottawa train tunnel. However, you omitted the 1910 CPR proposal filed at the city registry to run tracks on the bed of a drained Rideau Canal and to bore a tunnel 50 feet under the surface of downtown Ottawa and to run steam engine trains under Wellington Street toward the then called Union Station in LeBreton Flats.
   I do not share your conclusions, however, because you are overlooking some very real and pertinent problems to this DOTT project. Foremost is the unpredictable cost due to engineering issues while another is an inadequate foresight in the transition needs of the entire region in this second decade of the third millennium. I describe the present DOTT plan as “tunnel vision”.
   The 1910 CPR proposal and the fact that Herbert Samuel Holt, a major investor in the Canadian Pacific Railway as well as being the chair of the Royal Bank of Canada, a rich man and a civil engineer, may have led the Conservative Prime Minister, Robert Borden, to appoint Holt as chairman of a Federal Plan Commission to plan the future growth of the city of Ottawa and the city of Hull. Edward H. Bennett, an American architect, was also appointed to this Commission and hence the Holt-Bennett Plan of the “Holt” Commission.
   Mr. Miguelez, you neglect to say that two tunnels were envisaged: one under Wellington St. for the steam railroad trains and one somewhat under Sparks St. for electric streetcars that would end up close to the newly built Union Station for a quick transfer to trains going east to Montreal or north to the Hull train station and beyond over the then recently built Alexandra Bridge. This plan, known as the 1915 General Plan for the Cities of Ottawa and Hull of the Holt Commission and tabled in the middle of the First World War, was also proposing a federal district to carry out its proposals. Then, as well as now, such a concept was and still is deemed unacceptable by the governments of Ontario and Quebec.
   The cost of a downtown tunnel in Ottawa is presently estimated at 2.1 billion dollars. This is an incredible sum. If each of those dollars would be a kilometre, the sum would be fourteen times the mean distance between the earth and the sun. If each of those dollars were merely an inch it would travel 1.3 times over the circumference of our planet. This is a capital cost of great magnitude to be totally paid with taxpayers’ dollars.
   We really have no idea how much this tunnel will cost because we can only make learned guesses at what is underneath our streets and buildings. The mass behind the cliff face upon which the Parliament Buildings are built is primarily limestone with random cross-sections of black shale. Furtively throughout are water-permeable small faults diverging from the Gloucester fault. This fault, starting somewhere between Ottawa and Cornwall and ending somewhere in the Gatineau hills, meets the Eardley fault near the downtowns of Ottawa and Gatineau. It crosses somewhat perpendicularly the Ottawa-Bonnechere Graben, a topographic depression and still seismically-active ancient rift valley in the Canadian Shield. The Ottawa River flows through this graben.
   Recent events of the seismic activity of the Ottawa-Bonnechere Graben are the 1935 Temiscamingue earthquake (6.1 on the Richter scale) and the Lake Kipawa earthquake east of North Bay in 2000 (Richter 5.1). A 4.5 Richter earthquake happened in Thurso on February 24, 2006. In comparison, the Haiti earthquake measured 7.0 on the Richter scale.
   The Ottawa-Gatineau area, being the 4th largest metropolitan area in Canada, is also listed by the Geological Survey of Canada as the third in Canada as an urban area most at risk of an earthquake. This first at risk is Vancouver on the Pacific Rim and the second is Montreal which shares the same seismic zone as Ottawa.
   Montreal had a Richter 6.2 earthquake in 1732. The Geological Survey of Canada estimates that there is a 10% chance of an earthquake in the next 50 years that would be strong enough to damage buildings in Ottawa. Of course, being built upon solid rock, there would conceivably be less damage to the Ottawa-Gatineau downtown buildings than to houses built on soft soil and Leda clay in the areas south of Orléans. However, structural damage with water and air intrusions would probably happen in the underground of Ottawa.
   In 1961, an addition the Bell Telephone building at the corner of O’Connor and Slater was built on Slater Street. After completion, the basement floor started to heave and this necessitated the continual re-alignment of the generators and switching units plus freeing the partition walls from the ceiling. Over a period of time, this heave reached 10 cm (4 inches) over a floor area of 223 square meters. Although the building was more than 2 kilometres away from the Gloucester fault, it was believed that the damage was due to the numerous minor faults emanating from the Gloucester fault. An investigation was done by scientists from the National Research Council.
   This investigation came to the conclusion that building across a fault zone permitted the entry of air that reacted with the water and sulphides present in the fault’s cracks that created an acidic medium that activated dormant bacteria to oxidize inorganic compounds in the shale which converted to substances with a larger mass and so on ….
   Let us keep in mind that this proposed downtown Ottawa tunnel transit system is much more than just a tunnel. It involves the building from the surface to deep underground of stations, entrance rooms, hallways, escalators, stairs, platforms and various servicing areas. All of these will have to be built by detonating through limestone and shale. Any structural and geological problems would necessitate cementation at great cost.
   I do not believe that burrowing a multi-billion dollar black hole under the vaults of the Bank of Canada is such a great idea.