Marty,
I was talking to a well known fisherman on the flats just the other day and he told me it was because of all the rains we got last year the sediment came from the rivers and now are on the Flats. He said that anytime the wind blows it stirs it up and it does not take much. He also said that it might take as long as 2 years before it settles down bearing no heavy rains.