|Simple cross section showing current|
water levels in the swamp
Case in point are the two extremes:
Deep Lake Strand and Pinecrest. Deep Lake Strand is the driest, only holding water in the deepest part of the strand, whereas Pinecrest (and to the east) water is still flooding well into the prairies.
As for the cause, that would be canals:
In one case whisking it away and in the other piling it up.