Quote:
Originally Posted by "W"
Right?? West side looks better than East side with weirs?
Whats up with that??
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There are several factors in play since the dredging of the ship channel that make the marshes on the SE area of Big Lake more susceptible to saltwater intrusion than the marshes on the S side of West Cove.
Probably the biggest factor is the fact that the dredging has given salt water a wide open path to the SE corner of Big Lake, but has added a significant barrier to the path to West Cove. Note that now there is both the 40 ft deep 400 ft wide ship channel and the original Calcasieu river channel leading bringing salt water into the SE part of Big Lake. The open part of the ship channel into the SE part of Big Lake is several miles long. In contrast, the dredged material was used to build up a barrier between the ship channel and West Cove, and there are only a couple openings a few hundred yards wide for the salt water from the ship channel to flow into West Cove. Recent enhancements (the three new weirs) to the water control structures in West Cove were more needed to improve flow of freshwater out of the marshes than to reduce flow of salt water back into the marshes surrounding West Cove.
The SE part of Big Lake is also subject to greater wave action and larger wind driven tidal flows owing to the greater fetch on the east side of the lake by comparison with West Cove. See:
http://en.wikipedia.org/wiki/Fetch_(geography)