Flood Aftermath: Minimizing Water Pollution

Flooding can cause a lot of damage to homes and property, and it is important to know how to minimize water pollution to protect yourself and your community from environmental problems. Floodwater can contain high levels of raw sewage and hazardous substances, which can lead to water-borne diseases such as intestinal problems, skin infections, and rashes. It is important to take steps to reduce the impact of flooding, such as preparing indoor and abovegound fuel tanks, removing manure stockpiles, and securing hazardous waste. After a flood, it is crucial to remove standing water, dry indoor areas, and properly dispose of any debris to prevent further contamination and health risks.

Prepare fuel tanks and hazardous materials

If flooding is predicted in your area, it is important to take precautions to minimize the risk of pollution and potential damage to your property. Here are some steps you can take to prepare fuel tanks and hazardous materials:

Firstly, identify the location of your fuel tanks and hazardous materials. If possible, move them to higher ground away from potential flooding areas. This includes items such as vehicle batteries, propane tanks, and fuel oil tanks. Ensure that your fuel tanks are securely anchored to the floor or ground to prevent them from tipping over or floating during a flood. This can be done by using concrete anchors or straps to keep them in place.

Next, inspect the tanks for any openings that are not watertight, such as vents, fill pipes, or gauge connections. If these openings are not watertight, floodwater can enter the tank and displace the fuel, creating potential health, fire, and environmental hazards. To prevent this, empty your fuel tanks with the help of a bulk fuel distributor, and plug the vents and fill pipes. If emptying the tank is not possible, ensure that the tank is secured and will not tip over or float away. Close all valves, hoses, and dispensers securely. For underground tanks, top them off and seal the vents and fill openings to make them watertight. Alternatively, remove the tank contents and fill the tank with water to prevent buoyancy.

In addition, if you have hazardous materials or wastes on your property, ensure that they are properly stored and secured. Drums and containers should be closed, secured, leakproof, and stored away from areas that may be affected by flooding. Properly label waste containers with the contents and mark them as "hazardous waste". If possible, arrange for the proper disposal of hazardous waste before the flooding begins.

Lastly, be prepared to act quickly in the event of a flood. Have contact information readily available for the relevant authorities to report spills or leaks of hazardous materials. For example, in Minnesota, the Minnesota Duty Officer can be contacted at 651-649-5451 or 800-422-0798. Taking these proactive measures can help minimize the risk of pollution and potential damage caused by fuel tanks and hazardous materials during a flood.

Remove waste and manure stockpiles

To minimize water pollution after a flood, it is crucial to remove waste and manure stockpiles. Manure contains bacteria, nitrogen, ammonia, and phosphates, which can contaminate water bodies and cause health issues for humans and animals. Here are some detailed steps to address this:

Firstly, it is important to divert water away from manure-storage facilities to prevent overflow. This can be done by implementing proper drainage systems and ensuring that water is directed towards vegetated buffer areas or catch basins.

Next, remove any manure stockpiles from areas that could be flooded. Stack solid manure on concrete pads to reduce nutrient leaching through the soil. Place the stockpiles in open-sided sheds, ensuring they are on level surfaces and above the seasonal high-water table to minimize the risk of runoff.

Additionally, utilize catch basins and grass buffer strips near open lots to capture and filter runoff before it reaches nearby waterways. For manure pits, use impermeable concrete, synthetic, or clay soil liners to prevent nutrients from leaching into the surrounding environment.

Properly dispose of manure by taking it to a commercial compost site or landfill. Manure should be treated as recyclable waste or trash, and it is essential to follow local regulations and disposal guidelines.

Finally, cover all manure storage piles with tarps or plastic to prevent direct contact with rainwater, and ensure that contaminated water is diverted away from creeks, rivers, and storm drains. By following these steps, you can effectively reduce the impact of waste and manure stockpiles on water pollution after a flood.

Protect your health

Floodwater can be extremely dangerous to human health, as it can contain hazardous substances and sewage. To protect your health, it is important to assume that all floodwater is contaminated. Here are some ways to protect yourself and your family:

Before a Flood

• Plan an escape route if you live in an area that is prone to flooding. Identify a safe place to go, such as a local shelter or a friend or family member's house.
• Prepare an emergency kit that includes water, non-perishable food, paper plates and cups, plastic utensils, extra clothing and shoes, blankets, a first aid kit, prescription medications, cash and credit cards, and important phone numbers.
• Check your sump pump. Clean the sump pump and pit, and test it by pouring water into the pit. If you don't have a sump pump, consider purchasing one.
• Make sure your downspouts are in place so that they can carry water away from your house as the snow melts.
• If you have fuel tanks, prepare them for flooding by emptying them or securing them to concrete anchors or deadmen in the ground. Ensure that valves to hoses or dispensers are securely closed.
• If you have hazardous materials or wastes, take steps to prepare them for potential flooding. Close and secure drums and other containers, ensuring they are leakproof, and store them away from potential flooding areas. Label waste containers with their contents and mark them as "hazardous waste". If possible, arrange for the proper disposal of hazardous waste before the flooding begins.

During a Flood

• Avoid contact with floodwater, mud, and dirt if possible. Do not wade through water, even if it is shallow.
• If you must come into contact with floodwater, wear protective clothing and gear, such as rubber boots or solid shoes, rubber gloves, and goggles. Cover any cuts or scratches with waterproof bandages.
• If you are using watercrafts such as kayaks, boats, or paddleboards during the flood, make sure to clean them well afterward to avoid contamination and infection.

After a Flood

• If your home has been flooded, remove standing water and dry indoor areas as soon as possible to prevent mold growth. Remove and discard anything that has been wet for more than 24-48 hours.
• Do not use your sewage system until the water in the soil absorption field is lower than the water level around your house.
• Do not drink or wash with water from a flooded well until it has been tested and is safe to use.
• Do not swim in waterways and beaches for at least 48 hours after heavy rain or flooding. Swimming in poor water quality can lead to illnesses such as gastroenteritis.
• Do not eat homegrown fruits and vegetables that have been in contact with floodwater unless they have been thoroughly washed and are not in an area under a boil water advisory.
• If you have children, protect them from chemicals and diseases in floodwater. Be aware that behaviors such as crawling or placing objects in their mouths can increase their risk of exposure and sickness.

Clean up after flooding

Flooding can cause a lot of damage and lead to health risks, so it is important to know how to clean up after a flood effectively. Here are some detailed instructions to minimise water pollution and the potential harm caused by flooding.

Firstly, it is important to prepare for a flood. If you have fuel tanks, ensure they are securely anchored and that vents and openings are above the projected flood level. Underground tanks should be sealed to be watertight, and it is advisable to empty them before a flood. If you have hazardous materials, ensure they are stored away from potential flooding areas and are securely closed.

If you are aware of an imminent flood, unbolt toilets and plug the outlet pipe, and do the same for shower drains. Put appliances like freezers and washing machines on blocks to keep them off the floor and protect them from water damage. If appliances cannot be moved, wrap them in polyethylene film to make cleanup easier.

After a flood, remove standing water and dry indoor areas. Remove and discard anything that has been wet for more than 24-48 hours, as mould can cause serious health issues. If you have a septic system, do not use it until the water in the soil absorption field is lower than the water level around your house. If your septic system has been contaminated with chemicals, take extra precautions to avoid contact with water or inhaling fumes.

If you are cleaning up after a flood, assume all floodwaters are contaminated. Avoid contact with polluted water and soil, and wear protective clothing, gloves, and goggles if you have to handle anything contaminated. It is important to boil water before drinking it, and to avoid homegrown fruits and vegetables that may have been contaminated.

Reduce flooding from other drains

Reducing flooding from other drains is an important step in minimising water pollution after a flood. Here are some ways to do this:

Toilets

Unbolt toilets from the floor and plug the outlet pipe using the same procedure as for floor drains.

Showers and Washing Machines

Shower drains can be plugged in the same way as floor drains. Washing machines and basement sinks are usually positioned with their drain connections about 3 feet above the floor, so they may not overflow unless the water level gets that high. If necessary, these drains can be disconnected and capped or plugged with commercial plugs or braced rubber balls.

Appliances

Prepare appliances for flooding by shutting them off at the fuse box or breaker panel. Put freezers, washers, dryers, and other appliances up on wood or cement blocks to keep the motors above the water level. If high water levels are imminent and large appliances can’t be moved, wrap them in polyethylene film, tying the film in place with cord or rope. The water will still get in, but most of the silt won’t, so cleanup will be easier.

Sump Pumps

Clean the sump pump and pit, and test the pump by pouring water into the pit. Make sure the discharge hose delivers the water several feet away from the house to a well-drained area that slopes away from the house. If the hose outlet is too close to the house foundation or on flat ground, the water may simply recycle down through the house drain tile.

Fuel Tanks

Anchor fuel tanks to the floor to prevent them from tipping over or floating in a flood, which can cause fuel to spill or catch fire. Make sure vents and fill line openings are above projected flood levels. If you have a propane tank that is the property of a propane company, you’ll need written permission to anchor them, or you can ask if they can do it for you.

Frequently asked questions