What happened in Pattaya: Soi 3 Mueang Aroi and the railway-side road

According to the local outlet 77 Kaoded (77ข่าวเด็ด), on 23 September 2026 at around 12:30, continuous heavy rain over Pattaya City in Chonburi province left water standing at several locations. The report named the area around Soi 3 at the Mueang Aroi junction, Sukhumvit-Pattaya Road, and the road running alongside the railway near Wat Thammasamakkhi. At some points the water was reported to be about 1 metre deep. Traffic was closed at certain spots and small vehicles were barred from passing.

A metre of water on a city road rises over the door sills of almost every roadside shophouse and reaches power sockets, display fridges, counters and ground-floor stock. Turning back small vehicles shows how dangerous those points were.

The provincial picture was serious too. According to the Department of Disaster Prevention and Mitigation (DDPM), as of 2 October 2026 flooding had affected 10 districts of Chonburi province and 118,723 households. These are figures as of that report date; they can change daily as rain and drainage conditions shift, so readers should follow the latest announcements from local authorities.

The key point for anyone cleaning up is the type of flood. This was an urban flood: rain fell faster than the drainage network could take it away, so water travelled across roads, through gutters, drains, sewer manholes and shopfronts before it entered buildings. That is not clean rainwater. It is a mixture of wastewater, food waste, rubbish, road oil and sewage pushed up from overflowing pipes, which is why germ control has to be part of the recovery plan from day one.

Sources: 77 Kaoded (23 Sept 2026) https://77kaoded.news/23/09/2026/disaster/sangk/74064/ and the DDPM situation report (2 Oct 2026). Figures change daily.

The setting: food shops, shophouses, rooms to rent and homes by the railway

Sukhumvit-Pattaya Road and its side streets are working neighbourhoods: food stalls, rice-and-curry shops, repair shops, grocery stores, rented rooms, and rows of shophouses with a business downstairs and the family home upstairs. Roads beside the railway often have homes built close to street level.

Buildings like these share three weak points when water reaches a metre. First, the ground floor sits level with the road or only slightly above it, so water enters as soon as it tops the kerb. Second, the ground floor is where the money is made: the kitchen, fridges and freezers, cooking equipment, customer tables and stock. When sewage-laden water flows in, all of these come into direct contact with germs. Third, many shophouses have toilets and floor drains on the ground floor. When street water is high, water in the pipes can push back up through bathroom and kitchen floor drains.

Example case: a chicken-rice shop in a side street near Mueang Aroi

Note: this is an illustrative example of a typical situation in a flooded shopping street. It is not a real person from the news report.

Imagine Nok, who has run a Hainanese chicken-rice shop on the ground floor of a shophouse in one of those side streets for years. On the morning of the heavy rain she opens as usual. Shortly before noon the water in the street climbs quickly to the edge of the pavement, and soon it pours into the shop. Nok and her son carry the stockpot, the rice sacks and boxes of sauces upstairs, but the large chest freezer and the stainless chopping counter are too heavy, so they sit in the water for hours.

When the water drops, Nok finds a film of silt mixed with litter across the floor, cloudy residue on the counter legs, a drain smell inside the freezer, and black water that has seeped up through the floor drain in the toilet behind the shop. Regular customers are already calling to ask when she will reopen. She wants to open as soon as possible because the shop is the family's main income. But she also worries that if she opens too early, before the shop is truly clean, someone could get diarrhoea and years of reputation could disappear in a day.

What should she do first, and how will she know the shop is safe to cook in again? The rest of this article answers that.

The germs that follow an urban flood like Pattaya's

The World Health Organization (WHO) and the US Centers for Disease Control and Prevention (CDC) both explain that floodwater is commonly contaminated with sewage, human and animal waste, and chemicals. Thailand's Department of Disease Control (กรมควบคุมโรค) issues warnings every rainy season about flood-related diseases including gastrointestinal infections, skin infections, conjunctivitis, leptospirosis and respiratory illness. In a commercial urban street like the one in Pattaya, the main threats fall into four groups.

1. Bacteria from sewage and waste

When drains and sewer pits overflow, the water in the street carries gut bacteria from people and animals, including Escherichia coli (E. coli) and Salmonella. These are common causes of diarrhoea, abdominal cramps, vomiting and food poisoning. For a restaurant, the specific danger is that these bacteria settle on counters, chopping boards, containers and the hands of whoever is cooking, then travel onwards to customers through food.

2. Leptospirosis

Streets lined with restaurants, markets and rubbish points usually support a rat population living in the drains. When the drains flood, rats move upwards, and the urine of infected rats can contaminate water and mud with Leptospira bacteria. The bacteria enter the body through cuts, scratches, or the lining of the eyes, nose and mouth. People who wade for long periods to carry goods, push vehicles or clean their shop without boots are at risk. Warning signs include high fever, muscle pain especially in the calves, headache and red eyes. Anyone with these symptoms after wading must see a doctor promptly and mention the floodwater exposure.

3. Viruses spread by hands, surfaces and crowding

After a flood, people spend more time close together: neighbours help each other carry things, staff clean the shop as a team, families move in with relatives. Viruses that spread through hands and shared surfaces have an easy time. These include norovirus and rotavirus, which cause severe diarrhoea particularly in children; respiratory viruses such as influenza and RSV, both common as the rainy season turns to the cool season; and the viruses behind hand, foot and mouth disease in young children. They sit on door handles, tables, payment counters, stair rails and toys, then move to the next pair of hands.

4. Mould and musty air

Pattaya is a coastal city where the air is already humid. When plaster walls, ceiling boards, plywood, cupboards and upholstered seats soak up water, mould can start to grow quickly. CDC advises cleaning and drying within 24 to 48 hours to limit mould growth. Mould does more than leave black spots and a musty smell: its spores can trigger allergies, asthma and airway irritation. For a restaurant or guesthouse, a damp smell also changes how customers feel the moment they walk in.

Who is most at risk in this neighbourhood

Everyone who touches floodwater carries some risk, but some groups need extra care. Older people living on the ground floor of shophouses or in homes by the railway are first, because immunity declines with age and many have chronic conditions. Young children come next: they play in water, touch the floor and put their hands in their mouths. Pregnant women are a third group, and a fourth is anyone with a chronic illness such as diabetes, kidney disease or lung disease, or with a weakened immune system.

In a commercial street there is another group that is often overlooked: the workers. Restaurant staff, cooks, cleaners, hotel and guesthouse staff, delivery and taxi drivers, and labourers who wade through water carrying goods spend the longest time in contact with water and silt. They often have small cuts on their hands and feet from lifting, and many cannot afford to take time off. Their risk of leptospirosis and skin infections is higher than average. Business owners should provide protective gear and tell staff to report immediately if they develop fever or muscle pain after wading.

What flooded shop owners and families in Pattaya are dealing with

Health: diarrhoea, rashes, infected wounds, allergy flare-ups and respiratory symptoms among family and staff. Income: every closed day costs money, yet reopening too soon can cost more. Time: if mould returns or the smell lingers, the whole job is repeated. Reputation: one online review about a stomach upset or a musty room can linger for months. Family: where the upper floors are home, rebuilding the business while worrying about children and elders is a heavy load.

Why soap, detergent or bleach on their own may fall short

Step one in any recovery is washing away silt with clean water and a cleaning agent. That step is essential and cannot be skipped. Soap and detergent lift dirt and grease from surfaces, so a large proportion of germs are rinsed away with the wash water. The limitation is that ordinary cleaners are not designed for high-level disinfection. Germs lodged in tile grout, table legs and the seams of counters may survive.

Many households therefore turn to chlorine bleach, which public-health agencies do recommend at appropriate dilutions. In practice, however, there are several cautions. Chlorine is corrosive to some metals, and a restaurant is full of stainless steel and aluminium; strong solutions or repeated use can leave marks and rust. Its sharp smell interferes with kitchen work and can irritate the airways, especially in narrow shophouses with poor ventilation. It must never be mixed with ammonia or acidic toilet cleaners, because that releases hazardous gas, a mistake that happens surprisingly often when people are cleaning in a hurry.

Finally, chlorine works only while wet; once it evaporates it leaves little ongoing protection, and busy post-flood surfaces are quickly re-contaminated. Fans, air freshener and painting over mould only hide what you see or smell.

The solution: CHEMGENE HLD4H, a medical-grade disinfectant for the step after cleaning

Once silt and dirt have been washed away, the step many people skip is disinfection with a product designed for that job. CHEMGENE HLD4H is a medical-grade high-level disinfectant made in England. According to the product information, it is used in hospitals, clinics, laboratories, schools, offices, airports, homes, and elderly and child care settings.

According to the product information, CHEMGENE HLD4H is listed as effective against bacteria, fungi and mould, mycobacteria, Salmonella, and a range of viruses including influenza H1N1, RSV, norovirus, hand, foot and mouth disease virus, and SARS-CoV-2. The product page states that it kills within 1 minute, reports 99.85% efficacy against COVID-19, and provides residual surface protection for up to 14 days, which sets it apart from products that stop working once they evaporate.

For Pattaya restaurants and shophouses full of equipment in mixed materials, one feature stands out: according to the product information, CHEMGENE HLD4H is non-corrosive to stainless steel, aluminium, rubber, plastic and fibreglass. It is biodegradable, and the product page says it is safe for people, pets and medical equipment when used as directed. It comes with several dilution options, 1:30, 1:50, 1:60, 1:100 and up to 1:200, so you can choose according to the task and risk level specified on the label.

On standards, the product page lists tests and approvals from Mahidol University, NHS England, ISO 9001:2015, ISO 13485, SGS, Intertek, CE, and the European standards EN 13727, EN 14348, EN 13624 and EN 14476.

A disinfectant does not prevent flooding and is not a medical treatment; it reduces surface infection risk during recovery. Anyone who is ill should see a doctor.

Step-by-step recovery for Pattaya shops and homes: wash first, then disinfect

Step 1, safety first: before going in, make sure the main breaker is off. Do not switch on lights or plug in anything that is still wet. Check the structure, doors and floor for subsidence. In a restaurant that cooks with gas, check hoses and cylinders before use. Always wear rubber boots, rubber gloves and a mask.

Step 2, remove and sort: separate what must be thrown away. That includes all food and ingredients that touched floodwater, even if the packaging looks sealed; food from fridges and freezers left without power for a long time; sponges, hand towels, wooden chopping boards that soaked in water, and absorbent materials that cannot be cleaned. Keep hard items such as stainless pots, trays and glassware aside for washing.

Step 3, get every bit of silt out: push silt out of the building with shovels and squeegees, then wash floors, walls, counters and table legs with clean water and detergent. Scrub grout lines and corners where silt sticks. Work top to bottom and inside to outside, then rinse with clean water. This is the most important step, because every disinfectant works less well on surfaces still carrying mud and organic matter.

Step 4, dilute CHEMGENE HLD4H per the label: mix with clean water at the dilution the label specifies for surface disinfection. The product range runs from 1:30 to 1:200; choose the rate the label recommends for higher-risk work such as surfaces exposed to sewage. Label every spray bottle or bucket you mix.

Step 5, apply thoroughly and respect the contact time: spray or wipe onto surfaces that have already been cleaned, wetting them fully, and leave for the contact time stated on the label. Do not wipe off early. Focus on kitchen floors, counters, table legs, the inside and outside of fridges and freezers, toilets, floor drains, door handles, stair rails and the payment counter.

Step 6, ventilate and dry: open doors and windows and use fans to speed drying. Walls that absorbed water need to dry as fully as possible. If partition boards or ceilings have swollen and carry deep mould, consider cutting them out and replacing them.

Step 7, repeat on a schedule: disinfect high-touch points routinely, and if it floods again, start from silt removal. Throughout, wear gloves and boots, ventilate, follow the label and keep the product away from children.

10 reasons Pattaya shops and homes choose CHEMGENE HLD4H after a flood

1. Medical grade, made in England. According to the product information, it is a high-level disinfectant used in hospitals and laboratories. See product details
2. Covers sewage-borne bacteria. Listed against bacteria and Salmonella, the group behind many food-poisoning cases.
3. Covers post-flood viruses. Norovirus, influenza H1N1, RSV and hand, foot and mouth virus are all on the list.
4. Helps tackle mould. Listed against fungi, a major problem in a humid seaside city like Pattaya.
5. Fast acting. The product page states it kills within 1 minute, useful for businesses that need to reopen.
6. Residual protection up to 14 days. According to the product information, helpful while people constantly move in and out.
7. Kind to stainless steel and aluminium. Protects the counters, freezers and kitchen equipment you have already paid for. Order CHEMGENE HLD4H
8. Flexible dilution. From 1:30 to 1:200, so one bottle covers a large area, economical for multi-unit shophouses.
9. Biodegradable. A more responsible choice when large volumes are needed after a disaster.
10. Independently tested and certified. Mahidol University, NHS England, ISO, SGS, Intertek, CE and EN standards are listed. View certifications

Before and after: a roadside shop on Sukhumvit-Pattaya Road

Back to our example. If Nok takes the second route, spending an extra day or two removing every trace of silt, discarding everything edible that touched the water, and disinfecting every surface systematically before opening, she may reopen slightly later than her neighbours. But she reopens with confidence, her staff know exactly what to do each day, and her regulars can sit down to eat without a second thought.

Recovery checklist for Pattaya restaurants, shophouses and homes

Before you start

• Switch off the main breaker and have an electrician check before use
• Inspect gas hoses and cylinders in the kitchen
• Prepare boots, rubber gloves, masks and splash goggles
• Cover cuts on hands and feet with waterproof plasters
• Photograph the damage for aid applications or insurance claims

While cleaning

• Throw away all food and ingredients that touched floodwater
• Remove all silt from floors, walls, counters, freezers and table legs
• Wash hard utensils with dish detergent, then disinfect per label
• Dilute CHEMGENE HLD4H per label, apply thoroughly, wait the full contact time
• Prioritise toilets, floor drains, handles, rails and the payment counter
• Never mix different cleaning chemicals yourself

After cleaning and before reopening

• Ventilate and let every area dry completely
• Check walls, ceilings and wooden cupboards for mould daily in week one
• Use bottled water or water you are sure is safe for cooking
• Set a daily disinfection round for high-touch surfaces
• Watch family and staff for fever, calf pain or diarrhoea, and see a doctor promptly if they appear

Frequently asked questions about disinfecting after the Pattaya flood

Q: The water is gone. Can I just spray disinfectant without washing first?
A: No. Always remove silt and dirt first, because mud and organic matter reduce the effectiveness of any disinfectant. The correct order is wash, then disinfect at the label dilution and contact time.

Q: Can I use CHEMGENE HLD4H on stainless counters in a restaurant?
A: According to the product information, CHEMGENE HLD4H is non-corrosive to stainless steel, aluminium, rubber, plastic and fibreglass, which suits kitchen equipment. Follow the label for food-contact surfaces.

Q: Which dilution should I use?
A: The product offers 1:30, 1:50, 1:60, 1:100 and up to 1:200. Choose according to the task as specified on the label. Surfaces directly exposed to sewage should get the rate the label recommends for higher-risk work. If unsure, call the team on 065-556-6294.

Q: Protection for 14 days means I don't need to clean again?
A: No. The 14-day figure refers to residual surface protection according to the product information, but surfaces that are wiped, washed or soiled again need cleaning and disinfecting again, especially if flooding recurs.

Q: We have small children and pets. Is it suitable?
A: The product page states it is safe for people and pets when used as directed. Keep children and pets out of the area while spraying, let surfaces dry, ventilate, and store the product out of children's reach.

Q: I have a fever and calf pain after wading to move stock. What should I do?
A: See a doctor immediately and say you waded in floodwater, because these can be signs of leptospirosis. Disinfectant is for surfaces, not for treating illness.

Q: Where is your team, and can you deliver to Pattaya?
A: The World Health Disinfection team is based in Bangkok. Contact us about orders and delivery to Pattaya and Chonburi by phone on 065-556-6294 or LINE @whd268.

Recover your Pattaya shop or home with confidence

Wash out the silt, then finish with medical-grade CHEMGENE HLD4H, used as the label directs, to cut the risk from flood-borne germs.

Order CHEMGENE HLD4H

Call 065-556-6294 · LINE @whd268 · worldhealthdisinfection@gmail.com

Related links and references

• All Chemgene products
• Disinfection services by World Health Disinfection
• 77 Kaoded, Pattaya flood report, 23 Sept 2026: https://77kaoded.news/23/09/2026/disaster/sangk/74064/
• World Health Organization fact sheets: https://www.who.int/news-room/fact-sheets
• CDC Floods: https://www.cdc.gov/floods/
• Thailand Department of Disease Control: https://ddc.moph.go.th/

Flood information is based on news and DDPM reports as of the dates stated; figures can change daily. Product information is from the product page. Always read the label before use.