## ② Implementing countermeasures for foreign species in rivers

One of the greatest threats to preserving biodiversity is the presence of foreign species. These species continue to spread their habitat throughout Japan, posing problems to the native ecosystem. As a countermeasure, we have circulated information such as the “Revised Version: Examples and Concept of Countermeasures in Rivers for Foreign Species (February 2011)” and are implementing measures against foreign species in various locations.

## (2) Initiatives to recover the water supply in rivers

In order to preserve a healthy river environment, it is essential to sustain a rich supply of water. For this reason, we have specified the required amount of water in the basic policies over river development, based on the habitat of plants and animals, scenery, and water quality. In addition to working to sustain the supply, we are proceeding with activities for clean river recovery in recession areas down the stream from dams of hydroelectric power plants. Meanwhile, in order to preserve and improve river environment downstream of dams, we are implementing flexible dam operation and tests for flexible operation (conducted in 18 dams throughout Japan as of 2012) to efficiently utilize a portion of the flood control capacity without hindering flood regulation. Furthermore, we work to restore the water supply of rivers in urban areas, where the average amount of naturally flowing water has diminished, by pumping treated water from sewage plants.

## (3) Promoting activities in the comprehensive management of sedimentation from mountains to coastal areas

Concerned that climate change will accelerate problems such as diminishing sand supplies to the coast, variation in river environments caused by changes in sedimentary flow, and coastal erosion caused by changes in littoral drift, in recent years, relevant institutions are working in cooperation to comprehensively control sediment flowing down from mountains to coastal areas. Specifically, we are strengthening cooperation with relevant institutions, by drawing up policies aimed at project collaboration in order to respond to problems caused by sedimentary flow from mountain streams, dams, rivers, and coast.

Source) MLIT

## (4) Environmental education on rivers

As natural environments close to communities, recently, rivers host a variety of activities such as environmental studies and natural experience activities. In addition, we are promoting the projects and disseminating of information so children can safely learn and play by riversides. Because there are hidden dangers, and proper knowledge is essential for safe activity, we cooperate with the NPO “River Activities Council (RAC),” which citizens’ groups played a central role in establishing, to promote the cultivation of river administrators. Moreover, to prevent incidents caused by sudden swells in rivers, we are implementing measures by referring to the “Action Plan to Prevent Water Accidents caused by Sudden Flooding” established in 2007, and the reports from the “WG on water accidents prevention in small and medium size rivers” which was established in response to the occurrence of the Toga River flash flood in the Hyogo prefecture in July 2008.