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Displacement from Ship causing damage

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Published on Jun 8, 2011

UPDATE:
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Since publication of this footage, shipping traffic has been slowed to proper speeds and monitored by the US & Canadian Coast Guard to ensure all vesels maintain compliance.

This video was part of a series of videos studied and analyzed by the USCG to determine that the upriver vessels were traveling anywhere from 3 knots to 5 knots over the allowed 8 knot (land relative) upriver limit (10.4 knot water-relative limit) during the shipping season.

Speed limits have now been re-enforced throughout the St Lawrence seaway, and the issues shown in this video have since subsided.

http://northcountrynow.com/news/ship-...


SHIPPING TRAFFIC INFORMATION
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Great Lakes Shipping traffic scaled up in the 1970s with the addition of the "seaway cut" at the entrance of lake St. Clair. This cut allowed larger vessels to navigate the great lakes, and the narrow connecting waterways (as seen in this video). Despite vessel size increases, commercial shipping vessels have coexisted happily with land owners. In fact, for nearly 100 years - shipping traffic and effects have been non-problematic in this region, due to vessels traveling at slow speeds through navigable waterways.

However, recent technical advances in GPS and computer aided steering mean that large vessels raging from 500 - 1,020 feet in length can now navigate the waterways much faster than before. Combined with shipping companies placing increased time-pressure on vessels - this has lead to ships moving much faster than seaway engineers have engineered for. Previously large Taconite Ore carriers, such as the vessel shown, moved much slower due to human operation of steerage and navigation.

While increased speed is good for profit, the negative effect is that faster speeds through narrow waterways cause an increased amount of "Tidal Bore" due to fluid dynamics and displacement https://en.wikipedia.org/wiki/Tidal_bore

Even small increases of speed of only a few Knots can greatly magnify the effects of tidal bore exponentially (an increasint log when graphed) due to water being a "non compressible medium".

The displacement effect in this video is being caused by a 1000' long Freighter heading northbound on the St. Clair river, running at 4 knotts over the allowed speed of travel early in the shipping season.

INFORMATION ABOUT THE VIDEO AND ISLAND:
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Many the cottages on Harsens Island have existed since the early 1800's, and all have coexisted, without issue, with shipping traffic happily. The small brown cottage in this video actually dates back to 1850 (with obvious structural modifications made over 150 years).

This property in particular has been family-owned and is historically considered one of the original island cottages, with deeded family records dating back before Michigan declared statehood.

Information on Harsens Island:
https://en.wikipedia.org/wiki/Harsens...


NEGATIVE IMPACTS OF INCREASED SPEEDS DURING 2011 - 2014
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Until 2011 - This canal used to be a breeding ground for numerous fish species such as Bass, Walleye, and Sturgeon. Ship traffic in the main channel wasn't a problem in the past, as strict speed limits on freighters was maintained. Due to the washouts created during this shipping season, the breeding grounds were eliminated - and the St. Clair river sturgeon is now considered and "endangered species"
https://www.fws.gov/Midwest/sturgeon/...

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