What Causes Floods? Top 8 Common Causes of Flooding

Heavy rainfall – if there is heavy rainfall there is less chance of it being soaked up by the soil (infiltration ) so it runs off into the river. The faster the water reaches the river, the more likely it will flood. This will increase the flood risk, as the water will not be intercepted and flow into the river.

How floods form. A flood occurs when water inundates land that’s normally dry, which can happen in a multitude of ways. Excessive rain, a ruptured dam or levee, rapid melting of snow or ice, or even an unfortunately placed beaver dam can overwhelm a river, spreading over the adjacent land, called a floodplain.

• Heavy Rains. The simplest explanation for flooding is heavy rains.
• Overflowing Rivers.
• Broken Dams.
• Urban Drainage Basins.
• Storm Surges and Tsunamis.
• Channels with Steep Sides.
• A Lack of Vegetation.
• Melting Snow and Ice.

Most flash floods are caused by slow moving thunderstorms, thunderstorms that move repeatedly over the same area or heavy rains from tropical storms and hurricanes. These floods can develop within minutes or hours depending on the intensity and duration of the rain, the topography, soil conditions and ground cover.

Where Do Floods Occur? River floodplains and coastal areas are the most susceptible to flooding, however, it is possible for flooding to occur in areas with unusually long periods of heavy rainfall. Bangladesh is the most flood prone area in the world.

Flash flooding occurs within 6 hours of the rain event. Flooding is a longer term event and may last a week or more. Flooding along rivers is a natural and inevitable part of life.

Floods can be controlled by redirecting excess water to purpose-built canals or floodways, which in turn divert the water to temporary holding ponds or other bodies of water where there is a lower risk or impact to flooding.

Some of this water collects in large, underground reservoirs, but most of it forms rivers and streams that flow into the oceans, bringing the water back to its starting point.

Water gate is a clever PVC device that uses the pressure of oncoming water to stabilize itself. While more expensive than sandbags, it has been proven to be a highly effective means of containing flood damage.

Here are some methods of flood control to protect your home from rising water.

1. Raise your home on stilts or piers.
2. Install foundation vents or a sump pump.
3. Apply coatings and sealants.
4. Raise your electrical outlets and switches.
5. Install check valves on your pipes.
6. Grade your lawn away from the house.

The use of sandbags is a simple, but effective way to prevent or reduce flood water damage. Properly filled and placed sandbags can act as a barrier to divert moving water around, instead of through, buildings. Sandbag construction does not guarantee a water-tight seal, but is satisfactory for use in most situations.

Plastic Poly Tube Flood Barrier Another interesting alternative to traditional sandbags is the plastic poly tube flood barrier. These long plastic tubes can be pretty large. Sometimes, they may be as long as 50 feet or so and they can be filled with various substances.

Absorbeez

Polypropolene sandbags are a exceptional for flood control and a favorite choice for military personnel. Our military uses these sandbags for creating temporary and sometimes permanent bunkers and housing. The huge benefit of sandbags is they are lightweight when empty making them easily transportable.

HydraBarrier is an effective alternative to sand bags when it comes to spill containment and similar water containment and prevention applications. These water barriers are durable, come in a variety of sizes, are reusable, and can be filled when needed and emptied once used. This makes storing them a simple task.

How to Make Your Own

1. You’ll need a sturdy gym or duffel bag.
2. Buy a few bags of playground sand from the local hardware store-it’s near the concrete and usually comes in 50-pound tubes.
3. Fill a heavy-duty trash bag with sand.
4. Put it in your duffel bag (which keeps the sandbag from ripping) and zip it shut.

A: A heavy bodied or sandy soil is most desirable for filling sandbags, but any usable material at or near the site has definite advantages. Coarse sand could leak out through the weave in the bag. To prevent this, double bag the material.

“People sometimes use pillow cases, refuse sacks, or even carrier bags,” says Gainey. “And it doesn’t have to be sand. You can fill them with garden soil and then stamp them down so there are no gaps, and it will do the same job. The important thing is that they get heavy really quickly, so don’t overfill them.

play sand

Traditional sand bags are an effective way to deflect water and help protect structures from flooding. Sand bags can be made of burlap, polypropylene, polyethylene and nylon.