Why is it surprising that USGS calls it a gut Sloughs are often guts There is nothing in this article that indicates it is anything but a gut or slough not an estuary The friends may be a reliable source who knows I m told that if 3 blogs say something in agreement it can be considered reliable information If there are no reliable sources that say it s an estuary that information should be removed I would tag it as inaccurate but I am under threat of permanent community ban if I should question facts on Wikipedia in articles It s your article you want to call a slough an estuary okay I would just like readers to know it s unsourced information that appears to have nothing in the article backing it up I ve done that I wash my hands of this inland stagnant water estuary