A large display at Chongqing’s Smart Drainage Center monitors rainfall, water levels and urban drainage conditions in real time. (Photo/Chongqing Daily)
Chongqing - After weeks of intense summer heat punctuated by sudden downpours, Chongqing is using real-time monitoring to help its mountainous urban areas respond faster to flooding risks.
A coin-sized water-level sensor near Shenglin Road in Liangjiang New Area detected rising water during heavy rainfall on Aug. 2 and transmitted real-time data to Chongqing’s Smart Drainage Center.
The Smart Drainage Center's "intelligent brain," a digital monitoring and command platform, operates around the clock, with staff monitoring rainfall and water level data in real time.
That round-the-clock watch was put to the test on Aug. 2. At 11 p.m., the system detected flooding at a gas station in Kaizhou and issued another alert soon afterward. Hours later, a sensor near the Maternal and Child Health Hospital on Kaizhou Avenue reported rising water levels.
"Since yesterday evening, Chongqing has experienced a round of heavy rainfall moving from west to east. Yet the days of being overwhelmed by sudden downpours are over," said Yuan Jiang, head of the Flood Control Division of the Smart Drainage Center. "Standing water about 15 centimeters deep appeared on Shenglin Road, and the drainage team arrived within 15 minutes after receiving alerts from the system."
Yuan said Chongqing’s rainfall pattern shifts markedly in July. Rain in May and June is often a “prolonged battle,” driven by persistent warm, humid air from the southwest. July and August, by contrast, resemble a “guerrilla campaign”: localized severe convective storms can form, move and intensify quickly, unleashing heavy rain with little warning. That unpredictability makes early detection and rapid response critical.
The rainfall mainly affected central and eastern Chongqing, with Kaizhou recording 110 millimeters. The heaviest downpour struck between 10 p.m. on Aug. 2 and 1 a.m. the following day, keeping frontline response teams under pressure throughout the night.
Nighttime flooding risks once relied largely on residents’ reports and manual inspections, with multiple reporting layers slowing the response. During this rainfall, however, alerts reached local officials and frontline teams within three minutes of detection.
“The green indicators show that frontline officials have received the alert.” Drainage crews, traffic police and sanitation workers then moved quickly to clear drains, manage traffic and install pumps. Within about an hour, most of the water had receded.
Technology can issue the warning, but people still determine what happens next. Yuan said drainage crews, sanitation and community workers, business owners and other frontline responders must remain prepared, report risks and act effectively, creating a broader, community-wide flood prevention network.
To ensure no alert is missed, the Smart Drainage Center automatically sends follow-up reminders until frontline personnel respond. During the rainfall, Chongqing issued waterlogging warnings for 14 districts and counties, while warning signs and pumps were positioned in advance at all previously identified flood-prone sites.
The center issued 598 alerts in less than 24 hours. With heavy to torrential rain forecast across central and eastern Chongqing from Aug. 3 to 4, its digital platform tracked rain clouds in real time, combining smart monitoring, rapid coordination and public reporting to strengthen the city’s response to flooding.
(Li Jiayan, as an intern, also contributed to this report.)