Is there an environmental problem in Big Tub Harbour?

This is taken from the "Big Tub Working Group, Environmental Considerations, November 2014" report prepared on this issue (not work I can take credit for). A large amount of the observations were made by Ralph Suke.

Aerial photographs show a white ring around the Sweepstakes that represents a dead zone of silt that has been shifting (see photo from my last post). This phenomenon is not occurring around other wrecks and is not seen in aerial photographs taken before 1970 which is when boat traffic in this area began to increase in both number and size.

There is also a bank of gravelly, sandy deposit about 5 feet out from the port side of the wreck that is now heaped up about 1 foot high. This deposit has had the silt component “winnowed away” by the scouring current.

An NWRI Study describing Parks Canada monitoring from 1994 to 1998 describes measurements of silt depths taken by sinking calibrated stakes into the lake bottom around the wreck. These measurements indicated that silt was accumulating on the west side and being lost on the east side [of the shipwreck]. My own measurements indicate that the differential between silt depth on the east side of the Sweepstakes compared to the west side of the Sweepstakes has increased by 2.5 feet in the last 2 years alone (from 2012 to 2014). One can now reach right under the hull of the wreck into a shallow cave that has been scoured out under the ship. The structural integrity of the Sweepstakes is clearly in jeopardy.

The following are observations of the problem from the early 1990s:

“The historic vessels…which as a result of many factors continue to deteriorate in a much more rapid manner than would normally occur in nature”- Superintendent of FFNMP Mr. Bob Day in the 1991 Big Tub Operational Policy document.

“Bottom sediments immediately adjacent to the wreck have been scoured away leaving a depression of the order of a meter in depth”- NWRI study of 93/94

“Fine sediments are being selectively eroded on the east side (of the Sweepstakes) and settling out on the other side.”- NWRI STUDY of 93/94

The fact that there is an environmental concern in the west end of Big Tub Harbour is established by these observations. The question that remains is “what is causing the damage?”