Flooding and Pest Control
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During flooding, protecting life and property is the primary focus. But it is also critical to move quickly and step up the intensity of pest control to help protect your operation.
Flooding Creates Prime Conditions for Pests
Business owners and building managers: If you’re in an area affected by flooding, your focus is certain to be on cleanup and recovery. But in your rush to re-open, don’t ignore common pests that invade during and after floods.
"Flooding creates conditions which can allow pests to flourish and cause harm – from spreading disease to causing material damage to hurting your company’s reputation,” said Bennett Jordan, PhD BCE, Ecolab staff scientist.
Flooding, rising water and clogged sewer systems send rodents and wildlife running for food and shelter inside structures and under piles of debris. Standing water, along with garbage and other rotting materials, provide resources that flies, mosquitoes, ants and other occasional invaders need to breed. And moisture at building foundations may drive millipedes, centipedes and pill bugs indoors. Overall, pests tend to seek higher, dry ground during flooding. So even businesses that remain dry in a flood area risk infestation.
“The severity of pest problems after a flood depends on when and where it occurs and the size of the pest population before waters rise,” said Douglas Gardner, an Ecolab corporate scientist who has extensively studied rodents. Early spring flooding in colder parts of the country – places where pest populations may have been reduced by frigid weather – is less likely to create to pest issues than late spring flooding in warmer areas with strong pest populations.
Pest Control When Flooding is Predicted
If flooding is predicted for your area, it can pay off to talk with your pest control parter about reducing risks. Before waters rise, Ecolab pest control experts recommend that you:
- Identify and seal cracks and other openings under doors and flooring, at pipe chases and in false ceilings.
- Keep in mind that a mouse can enter through a space no bigger than a dime and a rat through an opening the size of a quarter. In southern and some coastal areas where roof rats live, it’s wise to inspect for and seal access points around the entire building, from the roof to below ground.
- Place rodent bait stations around the structure perimeter to monitor for rodent activity. Non-toxic bait may be used as a monitor only, and snap traps may be useful to identify the species of rodents in the area.
- Remove standing water where possible and address poor drainage.
Post-Flooding Pest Control
As waters recede, “It’s critical to move quickly and step up the intensity of pest management efforts,” said Gardner. “Pests can produce very large populations in a short time.” For example, a female house mouse can begin reproducing at five weeks of age and add 30–35 offspring to the population in a year. Insects can lay eggs and proliferate extensively in a matter of days.
As recovery begins, Ecolab pest control experts stress the need for ongoing rigorous inspection, sealing and monitoring. Vigilance should continue well after waters subside as some rodent populations have been known to surge weeks later, after they have recolonized.
As you work with your pest control professional, Ecolab pest scientists recommend the following actions to help reduce rodents, ants, mosquitoes, flies and other insects that normally live outdoors but come indoors in search of food, water and shelter.
Rodents:
- Inspect for structural damage. Look for exterior holes and other openings, keeping in mind that some rodents are excellent climbers. Carefully inspect under doorways and around the foundation, check around pipes and under false ceilings and flooring where rodents can run largely undetected. Prioritize, repair and seal access points. Install commercial-grade door sweeps.
- Assess exterior bait stations. Replace those that may have washed away or been damaged.
- Repair and replace sodden structural materials. When making repairs, use only industrial-grade materials, the only kind that can stand up under rodents’ powerful chewing. Also, when repairing walls, ask your pest services provider about interior treatments that can act as an additional pest barrier.
- Keep doors closed as much as possible. Inside frequently used doors set multi-catch traps for mice and monitor for intrusions. If there is evidence of rodents indoors, set baited snap traps inside. The traps may not catch all the rats, but they will provide evidence of where additional efforts are needed.
- Increase outside bait availability and the number of bait stations if monitoring indicates movement of rats and mice in your building.
- Remove debris from your property and store garbage in tightly closed containers; debris and garbage provide ideal harborage for rodents.
- Continue to actively monitor, seal and take other corrective actions as needed.
Ants, Mosquitoes and Flies:
- Inspect the property for breeding sites and identify pest species present.
- Eliminate standing water outdoors and indoors, including in drains. If drains cannot be dried completely, ask your pest service provider to apply treatments that interrupt the development of insect larvae.
- Promptly store or remove garbage. Organic material can decay and create prime breeding grounds for insects.
- Inspect for structural damage and repair or replace damaged windows and door screens, and close up spaces or cracks in the building’s exterior.
- Inspect and consider entry points. Keep doors and other entry points closed as much as possible, and place insect bait stations inside and outside doorways.
Contact Ecolab to learn how Ecolab Pest Control can help you reduce the risk of pest pressure in your facility, whether it be from a natural disaster or day-to-day activity.
More Pest Resources
Large flies pose a serious food safety risk and breed in places every restaurant has: Dumpsters and garbage.
An outside-in approach to fly control helps you minimize risk and protect your profit and brand.
To win the fight against rodents, teach employees how rodents can enter your facility, the signs of their presence and the damage they can cause.
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