Effectiveness of groundwater extraction in Beijing since the ingauration of the first phase of the South-to-North Water Diversion Project, China

Abstract

This study assess the effectiveness of groundwater pressure extraction in Beijing since the opening of the first phase of the South-to-North Water Diversion Project, using survey and evaluation methods. Firstly, an analysis of water consumption structure and the usage of diverted river water in Beijing in recent years was conducted. Secondly, the volume of groundwater pressure extraction in Beijing after the project's inauguration was examined, revealing a decrease from 1.96 billion m³ in 2014 to 1.35 billion m³ in 2020. The proportion of water supply reduced from 52.3% in 2014 to 33.3% in 2020, leading to an optimized water supply structure. By the end of 2020, groundwater pressure extraction in Beijing is estimated at 446 million m³, with a substantial reduction in over-exploitation of groundwater. Groundwater resources have been effectively replenished, and the strategic reserve capacity has been enhanced. Furthermore, this study evaluates the change in groundwater levels as an indicator of the effectiveness of pressure extraction. The declining trend of groundwater levels in Beijing has been effectively mitigated, and there has been a consistent rebound in groundwater levels over the past five years.