Jung Jeng Lake located in Mei Nong in south of Taiwan, is the origin of Mei Nong Hakka culture. Owing to stockbreeding hogs, cultivation and domestic wastewater in the upstream of Jiang Tz Liau River that finally flows into Jung Jeng Lake for years, the lake thus suffered extremely serious problem of eutrophication.
In addition, the water hyacinth remain seeds in the lake and reproduce resulting in speeding up the lacustrine silt that would greatly shorten the life of Jung Jeng Lake. Using artificial lagoon and artificial floating island were found able to improve the water quality of lake. Therefore, we could sightseeing resource, historic site, and ecological resources of Mei Nong. This research applied the advantages of ecological engineering methods to restore the Jung Jeng Lake, and thus the southern Taiwan unique Hakka tourism can be presented.