The 2026 (B.E. 2569) Flood Picture: Thailand and the Pa Sak Riverside Market

According to the Department of Disaster Prevention and Mitigation (DDPM), as published by the Government Public Relations Department (PRD) with data as of 06:00 on 7 October 2026 (B.E. 2569), the 2026 floods affected 27 provinces plus Bangkok, 123 districts, 984 sub-districts and 1,154,875 households, more than 3.1 million people. In a situation like this, many fresh markets and open-air markets must stop trading, move stalls or set up temporary sites, while residents still need to buy food every single day.

In Tha Ruea district, Ayutthaya, MGR Online reported on 29 September 2026 that red warning flags had been raised because the Pa Sak River was only about 10 centimetres below its banks. Vendors at the Tha Ruea fresh market moved their goods to safety, the market relocated to a temporary site, and sandbags were laid, while the Rama VI Dam was releasing water. On 5 October 2026 the Royal Irrigation Department forecast that water below the Rama VI Dam would rise by a further 1.00 to 1.20 metres and asked Tha Ruea district to stay on alert.

A market forced to dismantle its stalls and flee the water tells us the hardest work is still ahead: the day the water drops and the market must reopen, when every surface has to be clean and safe enough to hold fresh food again.

Sources: PRD citing DDPM data as of 7 Oct 2026 (B.E. 2569), 06:00 (https://www.prd.go.th/th/content/category/detail/id/33/iid/548715); MGR Online reports of 29 Sep and 5 Oct 2026 (B.E. 2569) (https://mgronline.com/local/detail/9690000095127).

Example Case: The Day a Riverside Market Has to Reopen

Note: this is an illustrative example case built from situations commonly seen at riverside markets during high water. It does not describe any specific real market or person.

Uncle Sompong has looked after a small riverside fresh market for more than twenty years. When the water began creeping into the market yard, he and the vendors lifted tables, carried out chest freezers and moved their stalls to a higher road nearby. The temporary market kept food on people's tables, but everyone knew customers wanted to return to the old market with its roof, water, electricity and parking.

Days later the water slowly drained from the yard, and what it left behind silenced everyone for a moment. A thin film of mud covered the concrete floor. The drains behind the meat and fish stalls were choked with silt and smelled of rot. Stainless table legs carried a tide line at knee height. The rubbish pile behind the market had been scattered by the current and caught along the fence, and flies were everywhere.

His team of five spent two days shovelling mud and hosing down. The place started to look cleaner, but when it was time to apply disinfectant, the only tool they had was a hand-pumped garden sprayer. After almost a full day they still had not covered every stall. The spaces under tables and shelves and the long drainage channel at the back received almost no disinfectant at all, while vendors phoned every hour to ask, "Can we come back tomorrow?"

That night Uncle Sompong told the mayor: "If the market had an engine-powered backpack sprayer that could blow the mist under every stall, we could reopen faster and people would trust us more." It is the same question many market operators asked themselves after the 2026 floods.

Why Fresh Markets Are Especially Risky After Floods

Even on a normal day, a fresh market is rich in organic matter: blood and meat wash water, fish scales, vegetable trimmings and food scraps. Floodwater mixes sewage from drains, public toilets and waste piles into all of this and leaves it on floors, walls, table legs and in drains. At group level, the germs to know about are:

• Gut and sewage bacteria such as E. coli and Salmonella, major causes of diarrhoea and food poisoning. A market is exactly where these germs can most easily jump from surfaces to food.
• Leptospirosis. Markets with food waste often have rats. In a flood, bacteria from rat urine contaminate water and mud, so anyone cleaning without boots and gloves is at risk. High fever and calf pain after wading need a doctor.
• Gut viruses such as norovirus and rotavirus, which spread via contaminated surfaces and hands and can make many people ill at once.
• Respiratory viruses such as influenza and RSV, which spread easily when crowds squeeze into cramped temporary markets.
• Moulds on wood, tarpaulins, cardboard boxes and long-damp walls, causing musty smells and trouble for people with allergies.

A market's risk does not stay inside the market. Food bought there goes into every kitchen in the community, so a poorly restored market can spread diarrhoea and food poisoning across a whole sub-district. A market that is washed and disinfected systematically before reopening, on the other hand, becomes the starting point for the community's safe recovery.

Again: disinfection always follows mud removal and washing, and it is not medical treatment. Anyone who feels unwell after a flood should see a doctor.

The Pain Points Market Operators Face When the Water Recedes

1. Large areas full of corners. A mid-sized fresh market has dozens of stalls in rows, aisles between them, long drains, public toilets, parking and a waste point. Every stall has space under the table, under the shelves and behind the freezer where damp and dirt collect.

2. Vendors lose income every closed day. Vegetable sellers, fishmongers and curry-rice stalls mostly earn day to day. Each day the market stays shut is income gone, so the pressure to reopen is intense. Reopening too early, before the site is clean, puts consumers at risk.

3. Customer confidence. Customers remember that the market went underwater. If they return to bad smells or mud stains, they may shop elsewhere, and the market's reputation can suffer for a long time.

4. Market standards and inspections. Markets must meet local sanitation requirements. A systematic cleaning and disinfection procedure with written records lets operators answer officials and the community with confidence.

5. Limited labour. Vendors are also dealing with flooded homes, so the market team is small. A tool that makes the job several times faster is what markets need most.

6. Flies and smells. After the water drops, rotting food becomes a breeding ground for flies. Markets have to manage waste, wash and disinfect to cut both odour and breeding sites.

Why Hoses and Hand-Pumped Sprayers Are Not Enough for a Whole Market

Most market managers already own hoses, brooms, scrubbing brushes and pump sprayers. These are essential for washing, but when it comes to applying disinfectant across a whole market, they have clear limits:

• They cannot reach under stalls or behind freezers. Pump-sprayer droplets have no air stream to carry them, so they do not drift into the gaps where mud and moisture collect most.
• They take too long. Dozens of stalls need several people spraying all day, while the market needs to open as soon as possible.
• Large drops run off. Much of the chemical flows into the drains without wetting surfaces for the contact time on the label.
• Operators tire quickly. Pumping all day lowers spraying quality by the afternoon.
• Blasting with a hose is not disinfection. High pressure removes dirt, but disinfection needs a correctly diluted chemical that stays on the surface long enough.

An engine-powered backpack sprayer, or backpack mistblower, uses air from a fan to carry spray further and into gaps far more effectively, making it a natural fit for rows of stalls in fresh markets and open-air markets.

The Answer for Markets: SOLO PORT 423 Backpack Mistblower

The SOLO PORT 423 is an engine-powered backpack mistblower from SOLO Kleinmotoren GmbH in Germany, sold in Thailand by World Health Disinfection (WHD). The engine drives a fan that produces a strong air stream. Liquid from the tank is released into that air at the end of the tube, breaks into droplets and is blown a long way. The operator can stand in the aisle and let the mist drift under stalls and into corners, instead of crawling into each one.

Main Specifications (according to the manufacturer, SOLO)

According to WHD's product information, the unit is a ULV type producing droplets under 30 microns, which saves chemical. Real droplet size depends on the nozzle and settings.

Details Market Managers Will Appreciate (according to WHD's product information)

• A rotating spray tube with a wide-angle diffuser, ideal for working along rows of stalls and drainage channels.
• A translucent, UV-resistant tank so you always see the level, with a wide filler for quick refills of pre-mixed solution.
• A one-hand control lever to adjust throttle and flow and stop the engine instantly if someone walks near.
• A padded harness and 4-point anti-vibration mounts to reduce fatigue on long aisles.
• Made in Germany with MAHLE parts, a BING carburettor and a Nikasil-coated cylinder.

Optional kits for specialised work exist in the SOLO range. Ask WHD first so you choose what suits your market.

Not a Thermal Fogger: Get This Right Before Buying

Many market managers picture municipal staff walking through a lane with a "fogging machine" that fills it with white smoke to kill mosquitoes, so they search using that term. The SOLO PORT 423 is not a thermal fogger. A thermal fogger uses heat to turn chemical into smoke-like fog. The SOLO PORT 423 is a mistblower that uses air, not heat, to break liquid into droplets.

For a fresh market, the difference matters. Post-flood disinfection means getting a water-diluted disinfectant, mixed according to its label, to wet concrete floors, table legs, walls and drains evenly for the full contact time. It is not about releasing a cloud into the air. If the market also needs mosquito or insect control, talk to WHD about the right machine and product for that specific job.

10 Reasons Fresh Markets and Open-Air Markets Should Own a SOLO PORT 423

1. Reopen sooner. Maximum airflow of 1,400 m³/h according to SOLO lets you cover the whole market far faster than with pump sprayers, so vendors' income returns sooner.
2. Mist drifts under stalls. The air stream carries droplets under tables, shelves and behind freezers, where pump sprayers cannot reach.
3. Reach of about 12 metres. Stand in the central aisle and reach the stalls on both sides, or treat fences and waste piles from a safe distance.
4. A 12-litre tank. Spray several rows before refilling and spend less time walking back to mix chemical.
5. Chemical savings. WHD describes ULV-type fine droplets that wet surfaces evenly without excess running into the drains.
6. One person, a lot of ground. Even a small market team can finish spraying while others clean stalls and manage waste.
7. Useful all year. Beyond floods, it supports monthly deep cleans or community outbreak response under the market's sanitation plan.
8. Suits municipal and private markets. WHD positions the model for government agencies and large organisations, so a municipality can buy one as a municipal sprayer to serve several markets.
9. Durable and cost-effective long term. German-made with quality parts for repeated heavy use.
10. Expert guidance. WHD advises on disinfectants suitable for food areas, technique and machine care. See the SOLO PORT 423.

Before and After: Market Recovery When the Water Drops

Step by Step: Cleaning and Disinfecting a Fresh Market After a Flood with the SOLO PORT 423

A fresh market is a food-contact area. Every step must follow the disinfectant's label and safety data sheet (SDS) and the advice of local public health officers.

1. Check safety before entering. Inspect the roof structure, keep power off in flooded zones until an electrician has checked the system, and watch for snakes or other animals sheltering under stalls.
2. Remove all damaged food and goods. Food that touched floodwater must be thrown away, never sold. Move usable goods and containers out before spraying.
3. Shovel mud and clear drains. Remove silt from channels and grease traps, bag rubbish in heavy-duty bags and take it to the collection point.
4. Wash with water and detergent. Scrub floors, table legs, walls, chopping boards and stall surfaces, rinse, and let them drain. Grease and mud stop disinfectants working fully.
5. Choose a product suitable for food areas. Use a registered disinfectant whose label allows use on food-area surfaces, such as WHD's Chemgene HLD4H, mixed at the label rate, and follow any label instruction to rinse direct food-contact surfaces afterwards.
6. Cordon off and inform vendors. Post no-entry signs, announce the spraying time clearly, and keep everyone and all animals out of the zone.
7. Check the machine and put on PPE. Inspect the tank, hoses, nozzle and harness; refuel only with the engine off and cool; wear ear protection, gloves, goggles, a respirator as the label requires, coveralls and boots.
8. Spray to a plan. Start upwind and work along each row: under tables, under shelves, walls, drains, toilets and the waste point. Surfaces should be evenly damp but not running. Never spray into the wind or toward people.
9. Wait for contact and re-entry times. Respect the label's times, then rinse food-contact surfaces as the label directs before vendors return to set up.
10. Clean, store and record. Rinse the tank and lines with clean water, clean PPE, log date, zones, chemical and operator, and post a notice that the market has been washed and disinfected.

Once trading resumes, set up handwashing points, clean stalls daily after closing and repeat deep cleans according to the market's plan.

Safety When Using a Mistblower in a Market

• It is loud: protect your ears. Sound pressure at the operator is 97 dB(A) according to SOLO. Operators must wear earmuffs or earplugs throughout, and neighbours should be told the work schedule in advance.
• Limit session length. Engine vibration tires hands and arms. Rotate operators and take regular breaks.
• Chemical PPE. Chemical-resistant gloves, goggles or a face shield, a respirator as the label and SDS require, long sleeves and boots.
• Refuel safely. Switch off and let the engine cool before refuelling, away from charcoal stoves, gas burners and sparks. No smoking.
• Weight. 11.0 kg empty; with a full 12-litre tank the total can exceed 23 kg. Fit the harness properly and lift with good technique.
• No people, food or animals in the spray zone. Remove food, keep people and pets out and allow re-entry only after the label time.
• Train before use. Learn starting, flow adjustment, emergency stop and maintenance from the manufacturer's manual.

Frequently Asked Questions

1. How do you disinfect a fresh market after a flood?

Discard food that touched floodwater, shovel mud, clear drains, wash with water and detergent, let surfaces drain, then spray a registered disinfectant according to its label, wait the contact time, and rinse food-contact surfaces as the label directs.

2. What kind of disinfection sprayer suits a market?

Markets with many rows of stalls are best served by an engine-powered backpack mistblower such as the SOLO PORT 423, whose air stream carries mist under stalls and into corners and covers ground quickly.

3. What is the SOLO PORT 423 price?

It depends on quantity, accessories and procurement terms. Contact WHD for a quotation on 065-556-6294 or LINE @whd268.

4. Can a municipality buy it as official equipment for municipal markets?

Yes. WHD can provide specifications, a quotation and procurement documents. Confirm the equipment category with your procurement officer.

5. Can vendors sell food immediately after spraying?

No. Wait for the label's contact and re-entry times and rinse direct food-contact surfaces if the label requires it before food goes back on display.

6. How is the SOLO PORT 423 different from a thermal fogger?

It uses air rather than heat to break liquid into droplets. A thermal fogger uses heat to create smoke-like fog. For disinfecting market surfaces, a mistblower is the better fit.

7. Which disinfectants can be used in a fresh market?

Registered products whose labels allow use on food-area or the relevant surfaces, such as Chemgene HLD4H from WHD. Efficacy depends on the chemical and correct label use.

8. Does an open-air market without a roof need disinfecting?

Yes. A flooded market yard still holds mud and sewage residue. Wash first, then spray when the wind is calm and rain is not imminent so the disinfectant stays on surfaces for the full contact time.

9. What if we are not ready to buy a machine?

Markets or agencies that do not want to buy can hire WHD's disinfection spraying service, which is a separate service.

Reopen Your Market Faster, Cleaner and With Confidence

The 2026 (B.E. 2569) floods in Tha Ruea, Ayutthaya and elsewhere showed that the fresh market is the place a community most wants back, and it has to be the safest. The SOLO PORT 423 backpack mistblower helps market teams disinfect every stall in far less time. Ask for a quotation and advice today.

See the SOLO PORT 423 and Request a Quote

Call 065-556-6294 | LINE @whd268

Related Reading and References

• SOLO PORT 423 against dengue outbreaks for municipalities and SAOs (Thai)
• Spraying against emerging diseases with the SOLO Port 423 for provincial public health offices (Thai)
• Chemgene HLD4H disinfectant
• WHD disinfection spraying service (separate service)
• DDPM flood data as of 7 Oct 2026 (B.E. 2569): PRD
• Tha Ruea fresh market, Pa Sak River, 29 Sep and 5 Oct 2026: MGR Online
• Flood cleanup guidance: CDC