A Story from the Field: A Riverside Warehouse That Went Quiet for a Week

Hia Chai is the second generation to run a wholesale grocery business in Mueang Chachoengsao. The front of the business is a two-unit shophouse; behind it stands a high-roofed warehouse where consumer goods sit on wooden pallets and steel racking: rice, cooking oil, fish sauce, instant noodles, snacks, drinking water, washing powder, soap and tissue paper. His main customers are the small village grocery shops around town, whose owners come to collect stock every morning before opening their own doors.

When the 2026 floods came, water from the Bang Pakong River pushed into the warehouse to nearly half a meter. Hia Chai and his staff used the forklift to lift some stock onto the upper levels of the racking, but a large amount of goods on the bottom pallets sat in the water for several days. Cardboard cartons collapsed into pulp. Rice sacks swelled. Snack packets floated loose across the warehouse floor.

When the water receded, the warehouse was coated in sticky mud. A musty smell, mixed with the sour odor of wet rice starting to spoil, drifted all the way to the shopfront. Every wooden pallet had turned dark. The block walls carried a water line and the first black spots of mold. Two dead rats lay behind a pile of ruined goods. One of the workers who carried the wet stock out started getting an itchy rash on his legs, and the village shop owners were calling every day to ask when deliveries would restart.

"The stock that got wet is worth several hundred thousand baht," Hia Chai said. "Part of me hates to lose it. I wanted to wipe it down and sell it cheap. But another part of me is scared. If my customers sell it on and somebody eats it and gets sick, my family name is finished." The World Health Disinfection team's answer on this point was clear from the very first day, and it became the starting point for the whole warehouse recovery plan.

Rule Number One: Food and Goods That Touched Floodwater Are Discarded, Not Resold

Floodwater that has passed through streets, drains and septic tanks is contaminated with bacteria such as E. coli, other germs that cause diarrhea, and the Leptospira bacteria that cause leptospirosis, as well as chemicals and oil washed off the roads. These contaminants can work their way through cartons, bags, bottle caps and the seams of packaging, even when the outside looks undamaged.

Every food, drink and ingredient that came into contact with floodwater has to be taken out and discarded. It should not be wiped, washed or sold at a discount. That includes rice, instant noodles, snacks, bottled water, seasonings and canned goods. Household consumer goods that went underwater, such as washing powder, soap, tissue paper and diapers, should also be removed from sale, because their packaging is contaminated and you cannot guarantee their cleanliness to your customers.

Stock that sat on high racking and never touched the water should be checked pallet by pallet. If a carton is damp, moldy, gnawed by rats or smells wrong, remove it too. Goods that are completely dry with intact packaging can be moved to a clean, dry temporary space until the warehouse has been restored.

Photograph and list every damaged item for insurance claims or for discussions with manufacturers, and ask the municipal office or local authority how to dispose of large volumes of spoiled goods properly. Do not leave piles of ruined stock in front of the warehouse, where they quickly become a breeding ground for germs and rats.

Why the Warehouse Must Be Restored Before New Stock Arrives

Health Risks for Warehouse Staff

Warehouse workers lift boxes, drag pallets and walk through muddy areas all day. Small cuts on hands and feet easily come into contact with contaminated mud, raising the risk of skin infections and leptospirosis. Mold spores from wet pallets and soggy cardboard cause sneezing, coughing and allergy flare-ups. Rubber gloves, boots and a mask are essential every time someone works on the clean-up. This is general information, not medical advice; anyone with a fever or an infected wound after flood work should see a doctor.

Damage to the Next Delivery

If new stock is brought into a warehouse that still smells musty, has mold on the walls and damp pallets on the floor, the new cartons absorb that moisture and odor too. Rice and flour pick up smells especially easily. This second round of loss can be avoided entirely by restoring the warehouse first.

Rats and Insects Follow

Wet and rotting food attracts rats, cockroaches and flies. Getting spoiled goods out quickly and cleaning the warehouse thoroughly are critical. If you find a serious rat or termite problem, bring in a specialist pest control service directly.

The Trust of Your Retail Customers

The village shops that buy from you have to answer questions from the families who shop with them. A wholesaler who can say clearly that all flood-touched stock was thrown away, and that the warehouse was restored step by step, keeps those customers far more easily.

Common Fixes That Miss the Root Cause

• Wiping flood-touched stock and selling it at a discount: This puts consumers' health and your shop's reputation at risk. It should not be done under any circumstances.
• Hosing the floor and putting the old pallets straight back: Wooden pallets that were underwater hold contaminated water deep inside. They become a source of mold and odor. Replace them, or use plastic pallets that have been washed and disinfected.
• Pouring strong bleach across the warehouse: The fumes irritate workers' airways, and bleach does nothing for the musty smell soaked into walls and roof structures.
• Leaving the roller doors open and relying on the breeze: This helps air the space a little, but it does not kill germs in the mud left in floor joints and under racking.
• Accepting new deliveries immediately out of fear of losing customers: The new stock ends up damaged as well.

The WHD Solution: A Step-by-Step Recovery of the Emptied Warehouse

World Health Disinfection (WHD) restores warehouses and wholesale shops with two services. The first is our disinfection fogging service using CHEMGENE HLD4H through ULV equipment, which produces a fine mist that reaches floors, walls, steel racking, rack legs, roller-door tracks, the loading dock and the corners a broom cannot reach. The second is our ozone treatment service for rooms or zones that can be sealed, such as stockrooms, the office and the staff rest room, to deal with mold spores and musty odor.

We work only in areas where all stock has been removed. We do not fog or ozone goods for sale, and our service is never a reason to put flood-touched stock back on the shelves. For large warehouses that cannot be sealed completely, our team assesses how to divide the space into zones so that treatment is both effective and safe.

How the Work Is Done

1. Site survey: We check the water level, the size of the warehouse, where mold is present, the electrics, the roller doors and which zones can be sealed for ozone treatment.
2. Advice on sorting and removing spoiled stock: We help plan the order of sorting, get discarded goods out of the building as fast as possible and advise on protective equipment.
3. Mud removal and pallet replacement: Mud is shoveled out, floors and joints are washed, waterlogged wooden pallets are removed, and the floor and walls are left to start drying.
4. Equipment protection: Computers, receipt printers, CCTV and electrical control boxes are covered or removed. An electrician should check the wiring and any electric forklifts before use.
5. ULV disinfection fogging: CHEMGENE HLD4H is fogged across floors, walls, racking, the loading dock and bathrooms, and given the proper contact time.
6. Ozone treatment of sealable zones: Rooms are closed and the generator is set for the space, with a controlled dose.
7. Ventilation and re-check: Doors are opened until the ozone has fully broken down, and odor and humidity are checked before new stock is accepted.

Hidden Problem Spots in a Warehouse

Roller-door tracks and the loading dock: Mud collects in the door tracks and in the drainage channel in front of the warehouse. Dig it out completely before fogging.

Staff rest room and toilets: Staff use these every day, so include them in fogging and ozone treatment. If the family lives above the shop, see our page on residential ozone disinfection.

Trolleys, forklifts and plastic crates: Wash off all mud, dry them and bring them into the fogging area. Electric forklifts must be checked by a technician before they are used again.

Standing water around the building: Pools of water breed mosquitoes. Our mosquito fogging service can treat the area around the warehouse.

The office above or beside the warehouse: Paperwork, invoices and the office carpet often hold damp and odor long after the warehouse floor is clean. Include the office in the ozone plan, and remove or replace carpet that was soaked.

A Realistic First-Week Timeline for a Flooded Wholesaler

Every warehouse is different, but many family wholesalers follow a pattern like this. On the first day after the water drops, nobody touches the electrics until they have been checked, and the team starts photographing and listing damaged stock for insurance. On days one and two, all flood-touched food and household goods are carried out and set aside for proper disposal, following the local authority's guidance, so the warehouse stops smelling of rotting rice and stops attracting rats. On days two and three, mud is shoveled out, the floor and drains are washed, waterlogged pallets go out, and the roller doors are left open in daylight to help the building dry. Dry stock from the top racks is checked and moved to a clean temporary space. Around days three to five, once the heavy cleaning is done and the building is empty, disinfection fogging and ozone treatment are carried out, followed by ventilation and a re-check. Only then are new pallets laid and the first new delivery accepted, starting with the dispatch area so village shop customers can be served again as soon as possible. Keeping to this order is what stops the clean-up from being undone by impatience.

Why Fogging and Ozone Complement Each Other

In a warehouse, the two treatments do different jobs. Fogging deals with surfaces: the film of silt and bacteria left on floors, rack uprights, door tracks and walls after the water drains away. The fine ULV droplets settle on those surfaces and give the disinfectant the contact it needs. Ozone deals with odor and airborne spores in spaces that can be closed. As a gas, it reaches gaps behind wall panels, ceiling voids above the office and the corners of stockrooms, breaking down the molecules that cause the musty smell rather than masking them. Fogging alone can leave a clean building that still smells of the flood; ozone alone can leave a fresher smell over contaminated surfaces. Together, after proper cleaning, they give the warehouse a genuine reset before new stock arrives.

Restocking Smart: How to Lay Out the Warehouse After Recovery

Once the warehouse has been cleaned, disinfected and ventilated, the way you bring stock back in can reduce the damage next time and keep the space healthier day to day. Start by keeping every pallet at least a hand-span away from the walls, so air can move and staff can see any damp patch early. Put food and drink on the upper levels of the racking wherever possible, and keep heavy, non-food items such as cleaning products lower down, but still on pallets rather than on the floor. Use plastic pallets in the lowest positions if your budget allows, because they can be washed and do not soak up water. Mark a visible line on the wall at the height the water reached this year; it becomes a simple reminder of how high to lift stock if a warning comes again. Finally, write a short flood plan: who moves which stock, in what order, and where it goes. Families who run wholesale businesses along the Bang Pakong know the river well, and a written plan turns that local knowledge into faster action.

10 Reasons Wholesalers and Warehouses Choose WHD

1. We say plainly that food and household goods that touched floodwater must be discarded, and we never suggest putting them back on sale.
2. We work only in areas where all stock has been removed.
3. We use CHEMGENE HLD4H on floors, walls, steel racking and the loading dock.
4. ULV equipment suits the wide floor areas and high roofs of warehouses.
5. Our ozone treatment is planned zone by zone for stockrooms, the office and staff rooms.
6. We advise on replacing waterlogged wooden pallets and setting stock away from walls and off the floor.
7. Computers, CCTV and electrical boxes are covered or moved before we begin.
8. We schedule the work so the dispatch area is ready first and deliveries to your customers can restart quickly.
9. The CHEMGENE 750 ml spray is available for counters, trolley handles and other frequently touched points.
10. The Master Ozone Generator is available for businesses that want to look after stockrooms and offices long term, with guidance on safe use.

In the Owner's Words

"The team told me straight on the first day that anything the water touched had to go. It hurt to hear, but it was also a relief, because I didn't have to gamble with my customers. Once the spoiled stock was out, they fogged the whole warehouse and ran ozone in the stockroom and the office. When the new delivery came in, the musty smell had faded a lot, and my staff were happy to go back in and work."
— A wholesale grocery owner in Mueang Chachoengsao (a story from the field)

Frequently Asked Questions

Q: Goods in sealed plastic wrap went underwater. Can I wipe them and sell them?
A: We do not recommend it. Food and goods that came into contact with floodwater should all be removed and discarded, because the cleanliness of the packaging and the contents cannot be guaranteed. Follow the advice of your local public health authority.

Q: Can you fog or ozone the stock instead of throwing it away?
A: No. Our services are for the building and for areas where stock has already been removed. They are not a way to make flood-touched goods saleable again.

Q: Our warehouse is large with a high roof. Can you ozone the whole building?
A: It depends on how well the space can be sealed. In warehouses with many vents and openings, we focus on fogging the whole area and use ozone in rooms or zones that can be closed.

Q: How long until we can accept new stock?
A: Once spoiled goods are out and the mud is cleared, fogging, ozone and ventilation are usually finished in one to two days, depending on the size of the warehouse.

Q: Can we keep using wooden pallets that went underwater?
A: We do not recommend it. Wood soaks up contaminated water and becomes a source of mold. Replace them, or use plastic pallets that have been washed and disinfected.

Q: What about stock that stayed dry on the top racks?
A: Check it carefully. If the packaging is completely dry, intact and odor-free, it can be stored in a clean, dry area and returned once the warehouse is ready. Anything damp, moldy, gnawed or smelling unusual should be discarded.

Q: Do we need to close the shopfront while the warehouse is treated?
A: During fogging and ozone treatment, nobody can be in the treated area, and if the shopfront shares open air with the warehouse, it should be closed for those hours as well. Many wholesalers schedule the work for a Sunday or after closing time, so that the shop can reopen the next morning once ventilation and the re-check are complete.

Q: How can we limit the damage next time?
A: Raise the lowest racking level, keep food on upper shelves, prepare a stock-moving plan for when flood warnings are issued, and check the warehouse for leaks before each rainy season.

Get Your Warehouse Clean Before the Next Delivery

Talk to the WHD team about disinfection fogging and ozone treatment for warehouses, wholesale shops and retail stores in Mueang Chachoengsao and nearby areas. Tell us the size of the warehouse, how high the water reached and when the space will be empty, and we will plan the work around your delivery schedule. Smaller grocery shops with a single back stockroom are welcome to contact us too.

See Our Disinfection Service

Book Ozone Treatment Here

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

Related Links

• Ozone treatment for odors and chemical residue
• Mosquito fogging service
• CHEMGENE HLD4H disinfectant
• All articles
• External sources: WHO: Floods and Department of Health, Thailand