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Ever since I read Keith Kinnaird’s article about building a second railway bridge across Lake Pend Oreille, I’ve been reading the comments that have been submitted by concerned parties, and I am thinking that everyone involved are ignoring the most important risk aspect of the project: the integrity and remaining operating life of the existing railway bridge in light of the increased railway traffic envisaged by BNSF once the second bridge is put into operation. The existing railway bridge is over 110 years old, and should probably be demolished and replaced with a new bridge itself which will ensure an operating life equivalent to the new bridge design.

Everyone is focused on permitting the new parallel bridge to be built, but if there is to be a failure in the future, it will likely be from continuing to use an old bridge that may be beyond its useful life. Foundations and piling have a way of deteriorating over the years, creating latent defects, and some strengthening work to the foundations of the old bridge has been carried out by BNSF a few years ago, which is a signal that some structural deficiencies were noted and hopefully fully rectified. But is that sufficient to continue with for the next 110 years? The design expertise that existed at the turn of the last century is not as sophisticated as that which is available today, particularly in earthquake zones, which this bridge happens to be located in. Likewise, strength of materials used today are far superior to that available 110 years ago. So, I would hope that before proceeding the USACOE would address the question of structural integrity and remaining operating life to ensure all parties understand the risk involved in continuing to use the old bridge.

Another aspect of continued use of the existing railway bridge is concern for boating safety. There have been several tragic accidents occur due to inadequate clearances. The new parallel bridge design appears to improve this safety aspect by incorporating increased spacing of support foundations, however, as long as the old railway bridge remains intact, the danger to boating continues to exist. If there were two parallel railway bridges, both designed identically, with increased foundation spacing, there would be a much safer boating situation.

I support the development of this project, and am glad to see a new railway bridge going up. I would just rather see two new bridges being built rather than continuing to operate the old existing bridge. The old bridge will have to be replaced at some point in the future. My question is when will that likely be, and will it be more cost effective for BNSF to address this now rather than wait until that future date is met?

J. MICHAEL PEARSON, P.E.

Sandpoint