Transition of water quality policies in Oregon, USA and South Korea: a historical socio-hydrological approach

We examined evolutionary pathways for water quality policies in relation to changing pollution events and socio-political system changes in Oregon, USA, and South Korea. Despite geographic and temporal differences, strong oversight and financial support of the governments with public pressure played a crucial role in point source control. As point sources came under control, focus shifted to nonpoint source policies that have evolved through different pathways according to the regional socio-hydrological context. In Oregon, cross-scale collaborative governance and watershed approaches have been encouraged from the beginning. While the South Korean government relied on the rules of the point source era in the early period, it emphasized collaborative and inclusive policies in the later period. The trajectories of both regions illustrate that the pivotal policies in the point source era do not necessarily guarantee successes in nonpoint source management, and hydra-headed problems such as climate change can further complicate water quality management.