Managing for Sustainability: The Development of Environmental Flows Implementation in China

Abstract

Environmental flows (e-flows) are important for river protection and restoration under degraded ecological conditions. With increasing public desire for and pursuit of sustainable development, e-flows are widely used to reflect the hydrological regime requirements for sustaining freshwater ecosystems and human livelihoods. Over the past 40 years, e-flows implementation has shifted from static minimum flows to dynamic flow components. However, e-flows standards used to manage flow releases from dams are to a great extent based on expert judgement and government supervision. These attributes make it difficult to effectively implement e-flows in the non-stationary world. The primary focus of this paper is to review the history, management systems and scientific basis of e-flows in China. Firstly, the study classifies the development phases into four periods and then analyses the underpinning legal system for e-flows implementation in each period, including the laws, regulations, policies and responsible authorities. Finally, the scientific basis and methods for e-flows determination and assessment were analyzed. The study showed that: (1) e-flows have been officially regarded as ecological flow in China, which evolved from minimum flow, and the contents and connotations are still broadening; (2) currently, there are too many authorities related to e-flows and complicated legal documents in China which lead to ineffective implementation; (3) the scientific basis of e-flows is enriched from the relationship between hydrological alteration and ecological response, so that the practices will be more holistic in China. Despite the successful practices of e-flows implementation in large rivers, there are challenges for implementing future e-flows in small rivers. This study recommended that future e-flows implementation be integrated with sustainable water management by setting clear responsibilities for governments, ministries, and other stakeholders.

A Comment on Chinese Policies to Avoid Negative Impacts on River Ecosystems by Hydropower Projects

“…2 L means large river (area > 100,000 km 2 ). 3 M means medium river (10,000 km 2 < area < 100,000 km 2 ). 4 S means small river (3000 km 2 < area < 10,000 km 2 ).…”

“…Considerable research has been done on the definition of environmental flows in China, the development of calculation methods, and implementation of environmental flows, including the selection of indicators for monitoring [15][16][17][18]. Given this level of research, no specific provisions on environmental flows have been formulated [3]. Where they do appear, environmental flows are grouped with other demands and given unclear priority.…”

“…Nearly one hundred thousand of multi-objective dams have been constructed, hydropower stations account for a half [1,2]. Hydropower stations are supposed to protect the ecosystems by clean electricity production and take into account the requirements of flood control, water supply, irrigation, shipping and fisheries [3]. The unguaranteed inflow is the direct cause of the insufficient ecological flow of some rivers and lakes [4].…”

Characteristics and Adaptability Assessment of Commonly Used Ecological Flow Methods in Water Storage and Hydropower Projects, the Case of Chinese River Basins

“…The reason may be that the Tennant method is a well-known method in the United States and the world, and it may be more suitable for the actual situation of rivers in the United States and is not as adaptable to research in China. In addition, the management of e-flow is different in rivers and damming rivers according to the policy [48]. Therefore, an adaptation study of this method in downstream areas of China's water storage and hydropower projects should be carried out.…”

Classifying Dams for Environmental Flow Implementation in China

“…Natural river ecosystems have been negatively impacted by dam construction and operation, and natural hydrological regimes have significantly changed since the 1950s [4]. Global degradation of freshwater ecosystems, biodiversity, and flood plains are related to dams [5][6][7]. Therefore, it is critical to mitigate the ecological impacts of dams while maintaining social and economic benefits.…”