The northeastern region of Minnesota recently experienced more than 6 inches of rain in some areas, flooding highways and raising concerns of the possibility of flash flooding. The heavy rain that fell in the area earlier this month raised the level of the Nemadji River which washed out sections of Highway 23 in Carlton County. Parts of surrounding states Wisconsin and Michigan have also dealt with flash flooding issues from the heavy rain, with one fatality in Wisconsin and a state of disaster declared in Michigan.
Flash flooding is a very serious problem because it can quickly cause widespread damage and put those in the area at serious risk. It only takes 6 inches of moving flood water for someone to drown and 2 feet of moving water to move vehicles. Significant stretches of Highway 2, Highway 23, and Highway 63 were washed out and experienced serious damage as a result, making it very dangerous to try and drive on these highways. Flash flood warnings were in effect for parts of Carlton and Pine counties in Minnesota after the storms.
Residents of Minnesota should be aware of the possibility of a flash flood occurring in their area. If you live near a lake or river, you should be especially cautious as the heavy rain earlier this month showed how fast a river can rise and overtake highways. Flash floods are damaging and deadly as they cause more weather-related fatalities in the U.S. than any other type of severe weather. The following tips will help you understand the causes and risks of flash floods, as well as what to do if flash flooding is expected in your area.
Main Causes of Flash Floods
Knowing the main causes of flash flooding can help you get prepared for the possibility before a flood takes over your property. Never underestimate the power of flash floods, they can occur very quickly even without heavy rain fall. The following are the most common causes of flash floods:
- Heavy rain: This is one of the biggest causes of flash floods as a heavy downpour can build up quickly, especially in areas with poor drainage, and it can cause rivers and lakes to rise and overflow.
- Rain over a long period: When rain falls steadily over a long period of time, it can eventually build up to cause flooding.
- Dam/ levee failure: A dam or levee that holds in large amounts of water can fail at any time and cause a fast, serious flood.
- Built up rainfall or snowmelt: The moisture from rain or snowmelt can overflow drainage and sewage systems beyond their capacity.
- Wildfires: Wildfires harden the ground which makes it unable to absorb water.
- Urbanization: Urban areas with few spots of grass and soil are more likely to experience flash flooding due to increased runoff and lack of absorption.
Areas at Risk of Flash Flooding
It is important to understand which areas at most at risk for flash flooding so you can avoid these areas during a storm, or brace for the possibility of a flood if you live in a high risk area. Flash flooding is typically a high risk in these areas:
- Areas with low elevation
- Areas around lakes, rivers, and other bodies of water
- Areas near levees and dams
- Areas around canyons
- Anywhere with low ground including creeks, stream beds, and ditches are vulnerable to flash flooding.
Flood Watch vs Flood Warning
When flash flooding is a possibility in your area, the National Weather Service gives alerts that are categorized as a flash flood watch or warning. While both alerts are cause for alarm, it helps to know the difference between the two:
- Watch: If a flash flood watch has been issued, this means that one can occur given the conditions, but it hasn’t happened yet.
- Warning: If a flash flood warning is issued, then the flooding has either already started or is expected to start within the next hour or sooner.
Steps to Take if a Flash Flood is Imminent
Flash floods are especially dangerous because they result in massive flooding in a very short period of time, and the water likely contains debris including rocks and building materials that can cause extensive damage. If your area has a flash flood warning, make sure you follow these steps to stay safe:
- Evacuate: if a flash flood is occurring, it is best to evacuate immediately. Leave your belongings behind and get yourself and your family to higher ground.
- Secure the home: You can take measures to secure your home if there is time to do it safely. Start by shutting off your utilities and unplugging major appliances. Avoid touching any electrical equipment if you are wet or if water has already flooded your home. You should also move valuable items to the highest levels of your home and bring in outdoor furniture if you can.
- Avoid walking in moving water: As mentioned above, it only takes 6 inches of moving water to knock a person over and cause a drowning. You should never walk through moving water and be very cautious when walking through non-moving water.
- Avoid driving through flood water: Driving in flood water is extremely dangerous. Remember, it only takes 2 feet of moving water to move a vehicle. If your vehicle is moved by the flood water, stay in your vehicle, but move to the roof of the vehicle if is starts filling with water.
Flood Damage Cleanup from SVMPS
The flash flooding that affected northeast Minnesota a couple of weeks ago shows just how quickly flash flooding can occur and how dangerous it is. We urge all residents throughout the state of Minnesota to review these safety tips and take the necessary action to protect your property and yourselves from harm. If you do experience damage from a flash flood on your property, SVMPS is ready to provide emergency flood damage restoration services, 24 hours a day. Our professionals will arrive on your property quickly to help contain the flooding and start the water damage restoration process to prevent serious complications including structural damage and mold growth.
You can reach SVMPS for emergency response by calling (800) 245-4622 in the Minneapolis and St. Paul, MN areas.