Hong Kong is mobilizing its defenses and bracing for potential severe flooding today as Super Typhoon Ragasa barrels towards the city, with emergency services and residents in low-lying areas taking urgent precautions based on hard lessons learned from past storms.

This morning, before a No 8 typhoon warning signal was raised at 2:20 pm, the low-lying coastal area of Lei Yue Mun — one of the identified black spots forecast to experience over one meter of flooding — was a scene of concerted preparation.

Workers contracted by the Drainage Services Department were seen stacking sandbags to chest-high levels, while restaurant owners reinforced their storefronts with sandbags and wooden boards. Fire service personnel conducted inspections, and powerful mobile pumping robots were stationed on standby.

READ MORE: South China goes all out, bracing for super typhoon Ragasa

Kwun Tong District Councilor Lui Tung-hai and the region’s Care Team members patrolled the area at around 10:40 am, distributing disaster-prevention leaflets and knocking on doors urging residents to take protective measures.

Lui highlighted the severe risk, noting that the area's lowest point sits at an altitude of just 2.7 meters. As a storm surge of four to five meters is forecast, the location could see widespread flooding.

Amid the preparations, local restaurant employee Wang Rong, who has lived in Hong Kong for only half a year, expressed anxiety as she helped barricade the business she works for. Having never experienced a major typhoon, Wang was particularly worried about potential water damage to electrical appliances, all of which had been elevated along with furniture as a precaution.

Some shops posted notices of a four-day closure and residents evacuated with their pets to safer locations.

Meanwhile, in Tai Po — another designated flooding black spot — crews had transformed the banks of the Lam Tsuen River into a defensive frontline by Tuesday morning. By 11 am, the river’s edge was lined with a radiant barrier of safety-orange — colossal inflatable dams installed by district drainage services crews. Tai Po’s low-lying areas – such as Tai Po Market and Kwong Fuk Road – face a recurrent flood risk when storms drive high tides up the Lam Tsuen River.

Gauges at the river entrance still bear the high-water marks of Typhoon Mangkhut’s record 4.5-meter surge in 2018 as a constant reminder of the community’s vulnerability to adverse weather conditions.

Moussa Nouhou, a crew member on duty since 7:30 am with his construction team, worked on installing the barriers and inflatable dams, expecting them to be operational by 12:30 pm. Nearby, another unit unspooled hoses for a high-capacity drainage robot to allow instant activation the moment the typhoon strikes.

“The river can rise fast,” one member said. “We’ll be here until the typhoon is over.”

The efforts are part of a city-wide response. Drainage Services Director Mok Wing-cheong said on Monday that 200 emergency teams were activated across Hong Kong, with multiple drainage robots deployed.

For Nouhou, who arrived in Hong Kong in 2016, the memories of Mangkhut’s rage -- of trees being uprooted -- remain sharp. Since joining a construction team in 2021, he has been battle-hardened by working on typhoon defenses, including recent flood-prevention work in Wu Kai Sha and Sha Tau Kok.

Nouhou said he now faces the threat of a new storm with steadier nerves. “We’ve been through a lot,” he reflects, “The experience, and seeing all these protections, makes me less afraid.”

A palpable sense of urgency also gripped the communities of Aberdeen and Ap Lei Chau on Tuesday morning. Residents swarmed supermarkets, stocking up on perishables and essentials, their rush creating long queues that stripped shelves of bottled water and instant noodles.

Across the districts, frantic fortifications were underway. Shop owners crisscrossed restaurant windows with tape, while staff installed makeshift flood barriers at a residential tower. In anticipation of the typhoon’s potential ferocity, trash buckets were lashed together or chained to fixed objects to prevent them from becoming projectiles.

Amidst the rising wind, a yacht pilot nicknamed Ah-Kei meticulously checked a desperate web of 14 heavy cables securing his vessel to the bank of a congested shelter — a stark contrast to the four that usually suffice. “Every extra line is a prayer for survival,” he said. Half a dozen crash pads hung like shields along the boat’s sides, a testament to the brutal battle ahead.

The 45-year-old had hoped to secure a safer berth deeper inside, as he had when Mangkhut ravaged Hong Kong in 2018. This time, he was unsuccessful. Now, on his boss’s orders, he is hunkering down for a two-day vigil aboard the vessel, stocked with supplies and tasked with ensuring its survival.

With forecasts suggesting Ragasa could surpass its predecessor's fury, Ah-Kei was clear about his priority: “I would abandon the vessel if it became too dangerous.”

Liz Cheung, who works in North Point, finished her job early at 12:30 pm, and boarded a ferry for home before the No 8 warning was issued. Her colleagues who live in the New Territories also headed home before the weather worsens.

Cheung said the government’s early warnings were more helpful than arrangements prior to typhoons Hato in 2017 and Mangkhut. However, she said that there could be improvements in the frequency and dissemination of information regarding transportation services.

Separately, the Macao SAR raised a typhoon signal No 8 at 5 pm and issued an Orange Storm Surge warning at 1pm.

The authority warned that low-lying areas may experience flooding between 1 and 1.5 meters, triggering a coordinated evacuation plan for storm surges in low-lying areas.

The Chinese mainland cities of the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) have implemented extensive precautions as Ragasa approaches.

Provincial railway services will be halted all day Wednesday, with operations expected to gradually resume in the early hours of Thursday as conditions improve.

The city of Shenzhen announced the closure of businesses and public transportation, from 2 pm and 8 pm on Tuesday, respectively.

READ MORE: HK steps up preparations as Super Typhoon Ragasa nears

Shenzhen Airport will suspend flights from 8 pm Tuesday, with services expected to resume gradually after the storm weakens on Wednesday. All ferry services at the airport's ferry terminal will be suspended through Thursday.

The Shenzhen-Zhongshan Link will close both directions at its toll stations from 8 pm Tuesday.

Authorities in Jiangmen, Zhongshan, Dongguan and several other Guangdong cities suspended classes, work, production and business operations on Tuesday.

Contact the writers at stacyshi@chinadailyhk.com