Rivers in Korea are classified as national river, local stream, creek. River law and creek law respectively define quantitative standards for national river and creeks. Whereas there is no quantitative standard for local stream.
Because of no standard for local stream, Gyeonggi-Do can not deal with the requests of cities that ask their creeks to be local streams. This study is to suggest a quantitative standard for local streams.
Generally watershed area, stream length, and population of flood area are used for factors that decide the grade of streams. Firstly this study suggests that watershed area and population of flood area could be proper factors of defining local streams.
Watershed area of 3~5㎢ is recommendable for the least area of local streams. 26.3% of creeks in Gyeonggi-Do are over 3㎢ watershed area and 9.1% of creeks are over 5㎢ watershed area. In addition, population of flood area can be used as a supplementary mean.
Secondly, this study recommends a method of using three factors of watershed area, stream length, and population of flood area. It can be applied to 1,991 creeks in Gyeonggi-Do to decide priority order for being local stream.
River law also should be reformed to define the quantitative standard for local stream. Furthermore Gyeonggi-Do regulations need to be established to adjust designation of local streams and creeks.
Considering 5㎢ watershed area applied to decide local stream, it needs 1,800 billion won for stream improvement projects. On top of that, considering 1,000 persons of flood area, it costs 140 billion won.
Because stream management systems of Gyeonggi-Do are relatively stable, it needs a prudential approach throuth cooperative adjustments between Gyeonggi-Do and cities.