Here is a link to the Butte La Rose, LA Atchafalaya river gauge reading.
http://nwis.waterdata.usgs.gov/la/nw...20,63160,00060
The Henderson "Swamp" area is connected to the Atchafalaya river by way of small bayous about 10 miles to the south. There is also a small "water control" structure a few miles south of the Henderson area....along the level on the west side.
Due to the water control structure and long distance away from the Atchafalaya river, the water level in the Henderson swamp is slow to change and does not rise and fall the same as the A. river.
Then up by US 190 hwy there is another water control structure where they can release water which flows into the Henderson swamp. It is my recollection that this structure is only opened during times when the water levels north of there are really high.