Sandbags are one of the most well-known devices for keeping floodwater out of your property. Unfilled sandbags and a supply of sand can be purchased from some DIY stores and Builders Merchants, but remember that if there is a flood in your area demand may exceed supply as people rush to buy them.
If you have not purchased sandbags and sand in advance, you can use alternatives such as pillowcases or refuse sacks and fill them with garden soil. Remember that they can get heavy quickly, so do not overfill, or fill them too far away from where you want to position them.
You can prevent or reduce flooding by taking steps to stop flood water entering your home or workplace. This can be done by blocking doorways and airbricks from the outside with sandbags.
How to fill and position sandbags
Unless you have access to a sandbag filling machine, this is a two-person job – one to hold the bag open and one to fill.
- Sand is abrasive – both people should wear protective gloves.
- Do not fill bags more than half full.
- It is not necessary to tie the end of the bag.
- Remove any debris from the area where the bags are to be placed.
- Lift the sandbags by the neck, place the half filled bags lengthways across the doorway and parallel to the direction of the water flow. Tuck the opened end under the filled half of the bag and position it pointing into the water flow. Ensure it is bedded in against the door and frame.
- Place bags in layers. Like a brick wall, make sure that in the next layer each bag overlaps the one below by half.
- Stamp bags firmly into place to eliminate gaps and create a tight seal.
Pyramid Placing Method
If you need to create sandbag protection that is more than three layers high you will need to build a pyramid style. For the structure to be stable, you should build the 'sandbag wall' three times as wide as you need it to be high. It will also be more effective if you alternate the layers lengthways and crosswise. Stamp each bag in place and tuck the loose end firmly under the filled portion of the bag.
Additional Waterproofing
Lay plastic sheeting across the side of the 'sandbag wall' that will face the floodwater. Weigh down with additional sandbags.
Remember, sandbags are popular but they have disadvantages:
- During an emergency sufficient quantities may be difficult to obtain.
- They are time-consuming and require two people to fill.
- They can be difficult to handle, particularly for older people or disabled people
- When they come into contact with floodwater they tend to retain contaminants such as sewage.
- Sacking material is biodegradable and will disintegrate if left in place for long periods of time. Polypropylene bags do not do this.
- Keep your sandbags out of the rain and sunshine to make sure they last longer.
- Floodboards can avoid some of these drawbacks.