Sichuan Deploys 81 Rainfall Radar Stations to Bolster Mountain Flood Early Warnings

Sichuan Province has completed a network of 81 specialized water-resources rainfall-measuring radars to address long-standing monitoring gaps across rugged mountain canyons and uninhabited upstream catchments. According to local authorities and state media, the network currently covers more than half of the province's land area and over 68% of identified mountain flood hazard sites. By transmitting real-time precipitation data every five minutes, the system has extended flood warning lead times and enabled pre-emptive evacuations during severe storms, with plans underway to add 58 more stations this year.

Traditional ground-based rain gauges often fail to cover uninhabited upstream valleys and complex terrain due to logistical and communication barriers. By networking phased-array rainfall radars, authorities can substantially improve spatial precipitation estimates and warning lead times, providing a practical model for zero-casualty emergency evacuations in disaster-prone mountainous regions.

Sichuan Province has established an operational network of 81 dedicated rainfall-measuring radars across its rugged river basins, significantly expanding monitoring capabilities in areas vulnerable to flash floods and debris flows, according to a report by People's Daily. The province, characterized by steep valleys and complex mountainous topography, has long contended with severe hydrological monitoring blind spots. In many upstream catchments along the Longmen Mountain range and other remote mountain systems, difficult terrain and limited telecommunications have historically prevented the installation and maintenance of standard ground rain gauges. To address this vulnerability, water resource authorities accelerated the deployment of phased-array rainfall radars. In Mianzhu City, an area frequently threatened by sudden mountain torrents, a 25-meter-tall radar station erected on a mountain summit in Guangji Town transmits precipitation data every five minutes. Local officials note that the high-frequency system tracks rainfall distribution, intensity, and cloud movement across previous blind spots, giving downstream communities crucial lead time to organize evacuations before torrents reach inhabited valleys. According to data from the Sichuan Provincial Department of Water Resources, the 81 networked radars now cover 51.25% of the province's land area, 57.34% of designated flash-flood risk zones, and 68.09% of recorded hazard points. Officials state that the networked array delivers high-resolution areal rainfall estimations, extending forecast horizons and enhancing predictive precision. The operational utility of the radar network was demonstrated in mid-July when torrential downpours struck Mabian County, triggering a major mountain torrent in Gaoshitou Village. Radar-enabled early warnings allowed local emergency authorities to relocate several thousand residents ahead of the floodwaters, resulting in zero reported casualties. To institutionalize these capabilities, the Sichuan Provincial Department of Water Resources developed an integrated radar data processing platform and accompanying mobile application. The system supports a tiered warning framework spanning provincial, municipal, county, and township levels, pairing risk assessments with local emergency response manuals. Provincial authorities plan to advance the construction of an additional 58 rainfall radar stations within the year, aiming to achieve full coverage across all high-risk mountain flood zones in the province.