The Lopburi Flood Situation in 2026 (B.E. 2569)

According to the Department of Disaster Prevention and Mitigation (DDPM), as reported by Daily News on 1 October 2026 (B.E. 2569), Lopburi province had flooding in five districts: Mueang Lopburi, Tha Luang, Phatthana Nikhom, Khok Samrong and Ban Mi. The flooding covered 23 subdistricts, 84 villages and 1,657 households, and at the time of the report water levels were still rising (source: Daily News, 1 Oct 2026 / 2569).

The national picture was just as serious. DDPM data as of 06:00 on 7 October 2026 (B.E. 2569), published by the Government Public Relations Department (PRD), showed 27 provinces plus Bangkok affected, covering 123 districts, 984 subdistricts and 1,154,875 households, with more than 3.1 million people affected (source: PRD).

Those numbers tell us that once the water goes down in Lopburi, local government work does not end with relief bags and pumping. It moves straight into restoring hygiene across whole subdistricts: village roads, fresh markets, community slaughterhouses, child development centres, temples and halls used as evacuation points.

Example Case: Three Days After the Water Fell, at a Riverside TAO in Tha Luang

Note: the following is an illustrative example case built from situations that commonly occur in local governments after floods. It does not describe a specific person or office.

On the third morning after the water began to drop, Somsak, the head of the chief administrator's office at a mid-sized TAO, stood in front of a subdistrict map covered with red pins. Every pin was a call from a resident: "the smell is terrible", "there are flies everywhere", "the kids are getting diarrhoea". The TAO's child development centre had been flooded almost halfway up the walls. Every stall in the weekly market was still caked in mud. The community hall, used as a temporary shelter, had only just emptied, and dozens of parents were asking when the childcare centre would reopen.

What the TAO had on hand was two or three hand-pump sprayers normally used on weeds, and a group of village health volunteers who were exhausted after days of carrying belongings to safety. The team tried disinfecting the childcare centre with a hand pump. One building took almost half a day. The liquid ran down the walls in streaks, and some corners were missed completely. The market, many times larger, had not been touched. Somsak did the rough maths: at this pace, covering every public site in the subdistrict would take a week or more, and residents could not wait that long.

That afternoon the TAO chief called an urgent meeting with three questions on the table. First, how do we get public spaces back into use as fast as possible? Second, how do we use disinfectant economically but still cover everything? Third, if the water comes again next year, how do we avoid starting from zero? The answer many local governments reach is to procure a motorised backpack mistblower as permanent equipment. That is the subject of this article.

Why a Community Needs Wide-Area Disinfection After the Water Recedes

A flood does not just bring water. It brings everything mixed into that water: sewage from overflowing drains and toilets, manure from pens and farms, rotting vegetation, rubbish and silt. When the water drops, all of it is left behind on floors, walls, furniture, market stalls and children's toys. In hot, humid weather, several groups of germs have a chance to multiply or survive long enough to reach people.

• Bacteria such as E. coli and Salmonella from sewage and animal waste, which cause diarrhoea, stomach cramps and food poisoning, plus the risk of leptospirosis from Leptospira bacteria that contaminate floodwater and mud.
• Viruses such as norovirus and rotavirus, which cause diarrhoea and vomiting and spread easily among young children, together with respiratory viruses like influenza and RSV, which pass easily between people crowded into shelters and public buildings.
• Moulds that grow on walls, ceilings, wood and fabric that stay damp, causing musty odours and triggering allergies, asthma and airway irritation.

A single household can usually manage its own home. Public spaces that the whole subdistrict shares, however, are the responsibility of local government, and the scale of that job is far beyond what small sprayers can handle. That is why community-level disinfection after a flood has to be planned as a system: the order of work, the chemical and the equipment.

Key principle: a sprayer is only a way of distributing disinfectant. How well germs are inactivated depends on the disinfectant itself, which should be a registered product used according to its label. Mud must always be removed and surfaces washed first. Disinfection is the next step, never a spray over dirt.

The Pain Points Local Governments Face After a Flood

1. The area is bigger than the workforce. One subdistrict can contain several villages, a market, a childcare centre, a school, a temple, a health promoting hospital and main roads. When many villages flood at once, disinfection has to happen in many places at the same time, while staff numbers are limited.

2. The workforce is already worn out. Officers and village health volunteers have worked hard since day one, evacuating people, moving belongings and running community kitchens. By the recovery phase everyone is tired. Tools that require constant hand pumping slow the work down further and make injuries more likely.

3. Time does not wait. The longer damp areas are left, the further musty odour and mould spread. At the same time, residents need the market, the childcare centre and public buildings back as soon as possible so they can return to earning a living.

4. Pressure to reopen. Parents want their children back in childcare. Vendors want to reopen their stalls. The local government has to be confident the site is clean enough first. Reopen too early, have children fall ill, and public trust disappears overnight.

5. Public health. The weeks after a flood are when diarrhoea, skin infections, leptospirosis and respiratory illness are commonly seen. Local government, as the level of the state closest to residents, is expected to act preventively, not wait until people are already sick.

6. Reputation and trust. Anyone can photograph a mud-covered market or a musty childcare room and post it on social media within minutes. Pictures of a well-equipped local team disinfecting in an organised way rebuild confidence.

Why Hand Pumps, Buckets and Mops Fall Short at Subdistrict Scale

Many local governments start post-flood disinfection with whatever equipment they already have. That is understandable, but once the area grows, the limits become obvious.

• Hand-pump sprayers deliver uneven pressure that depends on the person pumping. Droplets are coarse and come out in streams, so more liquid runs off than stays on the surface. Their reach is short, so the operator has to walk up to every spot.
• Buckets and mops are fine for washing floors but cannot reach high walls, gaps behind cabinets, the underside of market stalls or roof structures, and they use far more chemical than necessary.
• Small electric sprayers suit small rooms, but most need a power socket. After a flood, the electrical system may not be safe yet or may still be switched off, and their airflow is not strong enough for open areas.

Another common source of confusion is the difference between a thermal fogger (what Thai buyers often search for as "khrueang phon mok khwan") and a mistblower. A thermal fogger uses heat to vaporise the liquid into a white fog and is mostly used for mosquito control. A mistblower such as the SOLO PORT 423 uses an engine-driven fan to blast the liquid into fine droplets and carry them a long distance, without heat. That makes it the better fit for applying disinfectant onto surfaces across large indoor and outdoor areas.

The Answer for Local Government: The SOLO PORT 423 Backpack Mistblower

The SOLO PORT 423 is a motorised backpack mistblower made by SOLO Kleinmotoren GmbH of Sindelfingen, Germany. It is designed so one person can carry it and spray continuously without a power socket. That suits post-flood areas where electricity is not yet reliable, and it suits municipalities and TAOs that need to move from one village to the next within a single day.

Engine, tank, airflow, reach, weight and sound figures are according to manufacturer data from SOLO. The ULV and under-30-micron droplet figures are according to WHD product information; actual droplet size depends on the nozzle and settings used.

According to WHD product information, the unit uses quality components such as a Nikasil-coated cylinder, a BING float carburettor and electronic ignition. It has a rotatable spray tube, a long-reach nozzle and a wide-angle diffuser, a UV-resistant translucent tank with a wide filler opening, a one-hand control lever for throttle, dosing and stop, a padded harness and four anti-vibration mounts to reduce fatigue during long shifts. Other attachments, such as kits for dust or granules, exist in the SOLO range; ask the dealer about models and compatibility before ordering.

How it covers a large area. The heart of a mistblower is its air. The engine-driven fan moves up to 1,400 m³ of air per hour according to SOLO. That airstream breaks the liquid into droplets and carries them roughly 12 m horizontally. An operator can walk down the central aisle of a market and sweep the tube left and right so droplets reach under stalls and into corners, without stepping into every gap. Finer droplets than a hand pump produces also help the disinfectant settle as a thin film on surfaces, using less liquid per square metre and reducing puddles.

About the chemical: the machine only distributes the disinfectant. Germ inactivation is the job of the chemical you choose. Local governments should use a registered disinfectant at the dilution and contact time on its label. One example is Chemgene HLD4H, sold by WHD, which should be used according to its own label and safety data sheet.

10 Reasons Municipalities and TAOs Should Own a SOLO PORT 423

1. Covers public areas fast. With up to 1,400 m³/h of airflow and about 12 m of horizontal reach according to SOLO, a team can treat a market, a temple courtyard or a community hall far faster than with hand pumps.
2. No electricity needed. A petrol engine means the unit works immediately, even when village power is off or not yet safe to use.
3. One operator, fully mobile. No hoses to drag and no carts to push. It goes down narrow lanes, market aisles and up stairs.
4. 12 L tank. According to SOLO, the tank holds 12 litres, so operators spray longer between refills and spend less time walking back to the mixing point.
5. Saves chemical. Fine droplets spread more evenly than a stream. WHD product information describes the unit as ULV and says this saves chemical, which matters when emergency budgets are tight.
6. Reaches what hands cannot. The rotatable tube, long-reach nozzle and wide-angle diffuser help droplets reach high walls, the underside of stalls and roof frames.
7. Useful all year. It is not only for floods. Local governments can use it for disease control and sanitation work with the appropriate chemicals, which makes it good value as permanent equipment.
8. German engineering. Built by SOLO Kleinmotoren GmbH, and according to WHD product information it uses a Nikasil cylinder and a BING carburettor for consistent running.
9. Less operator fatigue. The padded harness and four anti-vibration mounts described by WHD help teams work longer with less strain.
10. Builds public confidence. A local team that can disinfect as soon as cleaning is done helps reopen markets, childcare centres and public buildings with more confidence. See the SOLO PORT 423

Before and After: TAO Community Disinfection With a Backpack Mistblower

This comparison is an illustrative example. Real results depend on site size, team size, post-flood conditions and the disinfectant used.

Step by Step: Community Disinfection After a Flood for Municipalities and TAOs

Step 1. Survey and prioritise. Map every site that needs treatment and rank them by how many vulnerable people use them: child development centres, health promoting hospitals, halls used as shelters, then fresh markets, public toilets, temples and village roads.

Step 2. Check building safety. Before going in, look for structural damage, cut power to any building where water reached the sockets, and cordon the area off from the public while work is under way.

Step 3. Remove mud and debris. Shovel out silt and remove rubbish and ruined materials, especially mattresses, carpets and paper that stayed wet for a long time.

Step 4. Wash. Wash floors, walls and frequently touched surfaces with clean water and detergent, because dirt reduces how well disinfectant works. Open doors and windows for ventilation.

Step 5. Prepare chemical and machine. Mix a registered disinfectant at the label dilution and fill the 12 L tank. Inspect the machine and refuel according to the manufacturer's manual with the engine off and cool, away from any flame.

Step 6. Put on protective equipment. Ear muffs or plugs, chemical-resistant gloves, goggles or a face shield, a respirator as the chemical label requires, long sleeves or coveralls and boots.

Step 7. Spray systematically. Start at the far end of the building and work back toward the door. Spray from top to bottom, sweep the tube slowly and evenly, never spray into the wind and never point the nozzle at people. In an open market, walk the central aisle and spray toward the stalls on both sides.

Step 8. Respect contact and re-entry times. Let the disinfectant stay on surfaces for the time on the label, ventilate, and reopen to the public only after the label's re-entry time.

Step 9. Record and communicate. Log the date, time, site, chemical and operator for reports to management and for answering residents. Announce which sites are ready through the village loudspeaker or the office's social media page.

Step 10. Look after the machine. Rinse the tank and nozzle with clean water, clean the air filter, store the unit somewhere dry and service it according to the manufacturer's manual so it is ready next time.

Safety When Using a Backpack Mistblower

• Hearing protection: sound pressure at the operator is 97 dB(A) according to SOLO. Wear ear muffs or plugs whenever the engine is running.
• Vibration and working time: limit each spraying session, rotate operators and take regular breaks, especially when treating several sites in a day.
• Chemical PPE: wear gloves, goggles or a face shield, a respirator, long sleeves and boots as the disinfectant's label and safety data sheet (SDS) require.
• Refuelling: always switch the engine off and let it cool before refuelling. Refuel outdoors, away from flames and cigarettes.
• Weight on the back: the dry unit weighs 11.0 kg according to SOLO. With a full 12 L tank the total is roughly 23 kg or more. Adjust the harness snugly and lift with correct posture, or have a colleague help.
• Keep people and pets away: never spray while residents, children or animals are in the area. Put up signs or warning tape.
• Re-entry times: follow the re-entry time on the disinfectant label strictly.
• Training: operators should be trained in using the machine, mixing chemicals and basic maintenance before working in the field.

Anyone, staff or resident, who feels unwell after wading through floodwater, with fever, calf pain, diarrhoea or skin rashes, should see a doctor. Disinfection reduces environmental risk; it is not a treatment for illness.

Buy Your Own Unit, or Hire a Disinfection Service?

For local governments with a large area, floods that return most years and staff who can be trained, owning a SOLO PORT 423 lets the team respond immediately without waiting in anyone's queue, and the unit can be used for other disease control work all year. For pricing and procurement terms, request a quotation directly from WHD.

Offices that are not ready to buy, or that face an urgent job beyond their team's capacity, can choose the WHD disinfection service. That is a separate service, carried out by WHD's own team with the service's own equipment and chemicals. Both options start with a phone call to the team.

Frequently Asked Questions

1. What is the SOLO PORT 423 price?

Pricing depends on quantity, accessories and your organisation's procurement terms. Please request a quotation from WHD on 065-556-6294 or LINE @whd268.

2. What is the difference between a backpack mistblower and a thermal fogger?

A thermal fogger uses heat to turn liquid into fog. The SOLO PORT 423 uses an engine-driven fan to blow the liquid into fine droplets without heat, which suits applying disinfectant to surfaces over large areas.

3. When should a municipality disinfect after floodwater recedes?

After mud and debris have been removed, surfaces have been washed and the building is safe to enter. Do not spray over mud or dirt, because the disinfectant cannot work properly.

4. How far does the SOLO PORT 423 spray?

According to SOLO, horizontal reach is about 12 m. Actual reach depends on the nozzle, wind and site conditions.

5. Which disinfectant should be used after a flood?

A registered disinfectant suited to the surfaces, such as Chemgene HLD4H sold by WHD, mixed and used strictly according to its label. Germ inactivation depends on the chemical, not the machine.

6. Is it heavy? Can an ordinary staff member carry it?

The dry unit is 11.0 kg according to SOLO, and about 23 kg or more with a full tank. A fit, trained operator can carry it, but teams should rotate and rest regularly.

7. Does it need electricity?

No. It runs on a 2-stroke petrol engine, so it works in flood-hit areas where power is not yet available.

8. Can a local government buy it as official equipment?

Yes. WHD sells the SOLO PORT 423 to government agencies and organisations, and can provide a quotation and supporting documents for procurement.

9. What if we are not ready to buy?

You can hire WHD's disinfection service as a separate job. Call 065-556-6294 or LINE @whd268.

10. Can people go back in right after spraying?

No. Wait for the contact time and re-entry time on the disinfectant label and ventilate well before reopening to the public.

Get your local team ready to restore communities after the 2026 (B.E. 2569) floods

Quotations and advice: call 065-556-6294 | LINE @whd268

Related Reading and References

• SOLO Port 423 backpack mistblower against dengue outbreaks, for municipalities and TAOs (Thai)
• Spraying against emerging diseases with the SOLO Port 423, for provincial public health offices (Thai)
• Chemgene HLD4H disinfectant
• WHD disinfection service
• Daily News, 1 Oct 2026 (B.E. 2569), DDPM report on Lopburi flooding: https://www.dailynews.co.th/news/6238476/
• PRD, DDPM data as of 7 Oct 2026 (B.E. 2569): https://www.prd.go.th/th/content/category/detail/id/33/iid/548715
• Department of Disease Control, Thailand: https://ddc.moph.go.th/
• CDC flood cleanup guidance: https://www.cdc.gov/floods/