maxerickson
I imagine the gnis node is an obscure name for the dam for the smaller impoundment at 32.563, -90.148. Only that impoundment is visible on older maps like https://prd-tnm.s3.amazonaws.com/StagedProducts/Maps/HistoricalTopo/2/13772/4892778.pdf and using https://geonames.usgs.gov/pls/gnispublic/ to look at the gnis info shows that the entry was created quite a while ago (where Lake Caroline seems more recent).