Flood Causes

Flooding is a global phenomenon and the #1 natural disaster in the U.S. and worldwide. Its effects are devastating and can result in significant loss of life, damage to property, and disruption to communities. But what are the exact possible causes of floods?

Let’s look at the most common natural and man-made flood causes.

Natural Causes of Flood

Heavy Rains

Flash floods occur within minutes to hours of excessive rainfall, often with little or no warning. These are typically caused by heavy rain, dam or levee failure, or a sudden release of water held by an ice or debris jam. Such debris jam causes a river or stream to overflow, leading to rapid flooding. Regardless of where you reside, you are encircled by systems and infrastructures intended to drain rainwater into basins and reservoirs. The system does its work most of the time, and you never have to worry about where the water goes when it pours.

However, when it rains severely, such systems become overburdened, and the water does not drain as rapidly as it should. In brief, drainage systems become clogged, and water rises – occasionally into residences. This is usually only seen after there has been an extended period of heavy rain.

Overflowing Rivers

Flooding in your region does not always have to be caused by heavy rainfall. For instance, if you live by a river and places upstream from you suffer intense rainfall, it might cause a significant overflow where you live. Most big rivers have many dams or levees to manage huge quantities of rainfall, and government bodies regulate the majority of river systems.

However, those authorities are often forced to make difficult judgments regarding how to run dams. They can frequently regulate the water and prevent floods, but not always.

Tsunamis and Storm Surges

Rain isn’t always to blame for floods. Storm surges from hurricanes and tropical cyclones, as well as tsunamis triggered by undersea earthquakes, can create considerable flooding. It can also occur during high tides in coastal areas. Thunderstorms can bring heavy rainfall in a short period, overwhelming storm drains and leading to urban flooding. This type of flooding is common in cities where impervious surfaces like parking lots prevent water absorption, increasing the flood hazard.

Thanks to modern technologies, we typically know about tsunamis and tropical storm surges before they come, but that’s not usually the case. For instance, in 2004, a quake off the Indonesian coast caused a tsunami and coastal flooding that came onshore with little notice.

Reservoirs, Rivers, and Lakes with Slanted Sides

Flooding is common when rapid runoff into reservoirs, rivers, and lakes occurs. This is frequently the scenario with canals, rivers, or streams with steep banks.

Lack of Vegetation

Trees, bushes, and other vegetation help avert floods by reducing runoff. However, water flows are unrestrained when there is minimal vegetation, like in an arid area or during a drought. A flash flood can occur because of strong rainfall following a drought. Luckily, basins and reservoirs can usually prevent this. Flash floods may be fatal in regions where there is no way to redirect the water.

Melting Snow

Most people living close to mountains are braced for spring floods, which occur due to snowmelt, generating ever-larger torrents that pour down the mountain. They know that if there is a lot more snow than usual, they should expect higher than usual water levels and perhaps floods.

Man-made Causes of Flood

Damaged Dams

Much of the USA’s infrastructure was developed in the 1900s, and it is beginning to show its age. When heavy rains fall, and water levels go up, aged dams might break, dumping cascades of water on unprepared residents.

This is what occurred in the aftermath of Hurricane Katrina in New Orleans in 2005. The failure of the levees exacerbated the flooding significantly more than it might have been normally. While we have grown to rely on twentieth-century architecture, and most of it performs a good job, there’s still the potential that a structure could collapse.

City Drainage Basins

Most of our cities are constructed primarily of concrete as well as other waterproof materials. When a city drainage basin is composed of concrete, there’s no soil for water to soak into. As a result, when such drainage basins load up, low-lying regions will flood.

This is especially true in major cities like Los Angeles and Houston. When severe rains fall, the basins meant to drain them are often overwhelmed.

Deforestation and Urbanization

Deforestation and rapid urbanization significantly alter the natural landscape, reducing the amount of vegetation that can absorb rainfall. When forests are cleared for agricultural or urban development, the water absorption capacity of the soil decreases, leading to increased surface runoff. In urban areas, the construction of buildings, roads, and other impermeable surfaces prevents water from soaking into the ground. This increased runoff can overwhelm drainage systems and lead to flooding, particularly in low-lying areas.

Secure Your Home with Neptune Flood Insurance

The average coverage claim following flooding in 2017, the year of Hurricanes Irma and Harvey, was $82,459. The following year, there was also a lot of flooding. Residents living 200 miles from the coast were flooded as a result of the Hurricane Florence rains. Many people did not anticipate being flooded and did not have flood insurance.

Could you afford to rebuild your home and replace all your belongings? Neptune Flood offers peace of mind from the unexpected. If you live in a designated flood zone, your mortgage holder requires flood insurance. However, as happened this year, devastating floods can happen in areas where flooding isn’t anticipated. Also, many homeowners with no mortgages don’t carry flood insurance.

Get a flood insurance quote from Neptune Flood in less than two minutes. Discover how affordable it is. Knowing you’re covered will let you sleep at night.

Frequently asked questions

1. What steps should I take immediately after a flood?

After a flood, ensure your safety first. Avoid floodwaters, check for hazards like downed power lines, report any damage to authorities, document damage for insurance claims, and start the cleanup process once it’s safe to return.

2. What are the health risks associated with floods?

Health hazards resulting from floods encompass contaminated water, mold growth, physical injuries, and stress.

3. How do I know if I need flood insurance?

Check flood maps and consult your insurance agent. Floods can occur in unexpected areas, so insurance is recommended even if you’re not in a high-risk zone.