The purpose of this study is to investigate the effects of the natural river conservation work and to find remedies for them,
targeting Jangsu-cheon with high frequency of use by citizens among the rivers in Incheon Metroplitan City, Korea; for
this, this study conducted investigations and analyses of Jangsu-cheon completed in December, 2008. As a result of
investigating 3 spots for the water system of Jangsu-cheon over a total of 3 years (2009, 2010, 2014), it was found that
benthic macro-invertebrates of a total of 3 phyla, 5 classes, 11 orders, 26 families, 56 species, and 980 specimens were
distributed there. When they were analyzed by year, 18 families and 30 species in 2009, right after the natural river
conservation work, and 22 families and 37 species in 2010, 2 years after the work, were found, with 7 species increasing
in number; after that, as a result of the investigation in 2014, 22 families and 38 species were found, which tells the river
has entered the stabilization stage since the recovery in 2010.Therefore, this study could identify: the water environment
of the river was improved due to the natural river conservation work for Jangsu-cheon; in addition, Jangsu-cheon showed
good ecological environment due to the continuous maintenance of the good wetlands in Incheon Grand Park in the upper
area of the river; and the natural river conservation work of Jangsu-cheon created positive effects.