It is recognized and protected under the Ramsar Convention held in March, 1998 and the Ramsar List of Wetlands of International Importance and it was designated as a Wetland Protected Area in February, 1999 and as a Natural Reserve (No.524) in January, 2011 by the Ministry of Environment and in February, 2012, the natural wetland areas around the Upo Wetland that need rehabilitation was designated as a wetland rehabilitation zone (62,940㎡).
The Wetland Protected Area has an area of 8.547㎢ and the Natural Reserve has an area of 3.438㎢. The area of submerged part of Upo Wetland is approximately 2.313㎢.
There are two competing views about the origin of Upo Wetland. One says that the Wetland was created 140 million years ago and the other says that it was created in B.C 4,000 which is about 6,000 years ago. However, in the sedimentary rocks near the Upo Weltand, footprints of a dinosaur which existed approximately 110 ~ 120 million years ago, fossilized raindrop patterns, insect fossils have been found and the claim that the wetland was created 140 million years ago is regarded as the more probable one.
Upo Wetland is a vast wetland full of beautiful aquatic vegetation that includes cattails, irises, reeds, water rice, water chestnuts, hornworts, arrowheads and thorn lotuses, Yellow Floating Heart lotuse, and summer migratory birds such as the Pheasant-Tailed Jacana, Grey Heron, Night Heron and winter migratory like the Whooper Swan, Falcated Duck, Eurasian Spoonbill, Bean Goose. Resident birds like the Little Grebe, Eurasian Eagle-Owl, Daurian Redstart and Common Kestrel can be found as well.
Also various living organisms such as the Northern Snakehead Crucian Carp, Common Carp, Pond Skaters, Mystery Snails, Paracercion v-nigrum (king dragonflies) and Korean Water Scorpion can be found.
The restoration project for the crested ibis which is an endagered bird species, has been carried out since 2008 in Upo Weltand.