In 1999, Beijing Drainage Group Co.Ltd (BDG) and Tsinghua University participated in Sino-German cooperation projects about " Technology of Groundwater Recharge utilization of Municipal Wastewater " and "Study on Advanced Wastewater Treatment Technology for Groundwater Recharge Projects ", in December 2001 pilot test of groundwater recharge by reclaimed water from sewage treatment plant was built in Beijing Gaobeidian, with size of 500m3/d, the total investment of 1.5 million RMB and the area of 2000m2.It began to be on operation in July 2002. The secondary effluent was treated through flocculation, sedimentation and filtration, then after treatment of activated carbon adsorption technology for advanced treatment in Gaobeidian sewage treatment plant, finally, the effluent that infiltrated through sand filter flowed into ground. To date, this pilot is the only groundwater recharge project with reclaimed water in urban area.     

Based on the original data from demonstration project, in 2006, the research direction and treatment process was improved. Ozone disinfection was adopted in the new treatment process. In May 2006, demonstration project of groundwater recharge was completed with the new treatment process, and the treatment capacity of the new pre-treatment equipment was 20m3/h.    

 The study on the pilot project provided much data and experience on groundwater recharge in China, and it has great significance for protection of the environment and solving the water shortage. In future, in accordance with practical condition the pilot project will continue to be improved.                                                                                                                                           

Wanghe Underground Reservoir

Wanghe Underground reservoir which was built in Laizhou achieved significant ecological, social and economic benefits as a water supply project.

Wanghe underground reservoir project was planed to invest about 147 million RMB with the total designed capacity of 56.93 million m3 and the total area of 68.5 m2, including water retaining barrier projects and water supply plant. At present, the project has been invested 75 million RMB, and the length of underground dam was 13 kilometers; impervious wall, more than 1000 the infiltration wells and 200 artificial infiltration ditches were built. Now the average water level around the rubber dam and artificial lake was 3.1 meters high, and in some place the water table was raised nearly 8 meters. And periodic sampling tests showed that chloride content in groundwater was lower than before, and the groundwater quality met Quality Standard for Drinking Water, and the projects solved drinking water problem for 10 villages in coastal area. Wanghe underground reservoir is effective for storing water, and the average annual infiltration is about 32 million m3/a, which provides 13 million m3 for agricultural irrigation, so that Wanghe underground reservoir is a successful project as groundwater recharge project.

Huangshui River Underground Reservoir

Huangshui river underground reservoir was built in downstream of Huangshui River with backwater area of 51.8 km2, total storage capacity of 53.59million m3 and the maximum regulating storage capacity of 39.29 million m3.

Dagujia River Underground Reservoir

The area of Dagujia River Basin in Yantai city is 2296 km2, including one large surface reservoir, two medium-sized reservoirs, 136 small reservoirs, 14 barrages and one large underground reservoir. The total storage capacity of Dagujia underground reservoir is 205.2 million m3, and the regulating storage capacity is 65 million m3; the completion of underground reservoir is effective to prevent sea water intrusion and underground water conservation, more importantly, it effectively alleviated deterioration of water environment caused by sea water intrusion and excessive exploitation of water, and the underground reservoir also becomes a beautiful scenery of this city.

Dagu River Underground Reservoir

 Dagu River is the largest river in Jiaodong Peninsula, in 1998 Dagu river underground reservoir was built in the middle and lower reaches of the valley plain along the ancient river channel with the total area of 421.7km2, the difference from north to south of 51km and the average width of 8km. The total storage capacity of underground reservoir is 384.13 million m3, and the regulating storage capacity is 238 million m3, the reservoir not only prevents the sea water intrusion, but also increases the water storage by intercepting water from the upstream.

Balisha River Underground Reservoir

Balisha River groundwater reservoir located in Longkou city with full length of underground dam of 756m, the height of underground dam fluctuates a great due to topographic condition, the material of underground dam is cement, which was injected underground using high pressure jet grouting technique. Impermeable Wall of the Dam contributes to the uplift of water table and intercepting underground flow.