Rivers are an important part of life on earth and the basis of human existence and development. Among all the earth's diversified ecosystems, rivers are one of the most common forms.

The United Nations 2030 Sustainable Development Goals clearly stated that everyone should have access to safe drinking water, water pollution should be reduced and river ecosystems should be protected. With that in the backdrop, and in order to raise the awareness of people from all walks of life on river protection and governance, the China institute of water resources and hydropower research (IWHR) has initiated a trial research on evaluating the happiness of rivers since 2020. The Chinese institute has released world river happiness report 2021 on March 22, to find out how happy these bodies of water are. Watch the video to find out how rivers are evaluated on being happy.