According to the Beijing Water Authority, from July 29th to 30th, the total precipitation in the city reached 1.649 billion cubic meters, generating 478 million cubic meters of water resources within the city, including 132 million cubic meters of surface water and 346 million cubic meters of groundwater. 

As of 8:00 am on July 31st, the total water storage in the city's large and medium-sized reservoirs reached 3.548 billion cubic meters, an increase of 47 million cubic meters compared to before the rain. Six reservoirs, including Miyun Reservoir, Guanting Reservoir, Ming Tombs Reservoir, Huairou Reservoir, Zhaitang Reservoir, and Daning Reservoir, achieved 100% flood retention, collectively increasing water storage by 37.82 million cubic meters. Among them, Miyun Reservoir received an inflow of 34.3133 million cubic meters, equivalent to an increase in water storage capacity equivalent to 17 Kunming Lakes.