Instructions
Haawal Flood Grating
Warning
Before using temporary flood protection barriers it is crucial that proper considerations for its use are made by someone qualified to do so.
Using any type of flood protection can have unintended consequences in areas further down the flood path. It is therefore crucial that these effects are taken into consideration.
The ground conditions must be known before using temporary flood barriers as the permeability of the ground will affect how much water is able to pass underneath the system. In use cases with leakage through the ground it may be necessary to complement the portable flood barriers with pumps.
Use gloves and other personal protection equipment when installing Flood Grating.
The barrier should be supervised at all times in situations where vandalism is a risk. Supervision is also recommended to ensure that members of the public do not stand close to the barriers during a flood. It can be dangerous to stand behind the flood barrier during a flood and this must therefore be avoided.
Floods are inherently unpredictable and dangerous. Even with qualified decisions around the use of the portable flood barriers there will always exist a risk of damage to property and personal injury that the supplier cannot accept liability for.
Installation overview
Flood Grating comes in two heights (90cm and 120cm).
The installation steps are the same for the two heights as illustrated below.
2
Insert the walls
4
Attach the support wires
Place the ground panels
1
Roll out the membrane
3
Weight the membrane
5
Step 1:
Place the ground panels
The panels are different on each side. One side is smooth and has a black square at the attachment point, while the other is rough and has a metal fitting at the attachment point.
Black Square, must face upwards
Place the Flood Grating panels on the ground with the flat side facing up, and with the pins facing away from the side that will be flooded.
The panels should be placed as closely as possible. However, there must be a gap of at least 5 mm to allow space for the wall to be inserted as described in “Step 2”.
Step 2:
Insert wall panels
The walls are attached to the bases by inserting the connecting pins of the wall panel into the row of square holes nearest the connecting pins of the base panel. (please note that the base panels and wall panels are interchangeable)
The flat side of the wall panel must face the flooding side while the rough side must face the dry side.
Step 4:
Attach the support wire
The support wire is attached by first pressing the bolt of the handle through the membrane, into the black attachment point. The handle is then rotated to tighten the bolt which also seals the hole created when penetrating the membrane.
The keys are then attached to the back of the wall (maximum 15 cm from the edge). The keys must be attached so that the wire is in slight tension.
Step 5:
Weight the membrane
Place a row of sandbags on the front of the membrane that ensure the membrane creates a seal against the ground. The sandbags should be placed with no gaps between them. The sandbags must not be overfilled to ensure they are flexible enough to adapt to uneven sections of the ground.
Step 3:
Roll out the membrane
Roll the membrane out over the base panels, as close to the wall panels as possible. Open up the membrane and fold the membrane over the wall. It is important that the membrane is able to rest against both the base and the wall.
In the event of strong winds while performing this step it is recommended to do it one module at a time. Roll the membrane past one module, and then fold it over the wall and attach the support wire as explained in step 4. Repeat this process until the whole membrane is rolled out. It is recommended to be at least 3 people when performing this step in windy conditions.
If more than 25 meters of Flood Grating is installed several membranes can be used. They must overlap with at least 1.5 meters and be attached with the included tape. The overlap must lay in the expected direction of flood current.
Important points:
Overlapping the membranes
The membranes are delivered on 25 meter long rolls. This means that if the flood barrier is longer than 25 meters, several membranes must be joined together. This is done by overlapping the membranes by at least 1 meter and then taping the seam with the included special tape. If there are water currents, the overlap should lie downstream. Be meticulous with the taping, as this, along with the water pressure pressing the membranes together, ensures a watertight seam.
Pay close attention to taping the overlap and tape the entire length of the seam.
Installation of the membrane and sandbags
The membrane is key to ensuring that the flood barrier is as watertight as possible.
To avoid the membrane being strained by the weight of floodwater, it is important that it is supported by both wall and base panels. The membrane must be installed so that it lies completely into the corner between the base and the wall. Pay close attention to this before the support wire is installed and locks the membrane in place.
The membrane should be installed correctly with support extending fully into the corner between the base and the wall.
Be meticulous in placing the sandbags along the front edge of the membrane so that they seal the membrane against the ground.
Be prepared and have a plan!
Flood situations can occur quickly and create difficult and unexpected situations. We therefore encourage all users of Haawal flood barriers to be well prepared before a potential floods hits:
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Ensure quick and easy access to the flood barriers and other equipment.
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Have a plan ready for where the flood barrier should be installed in various situations.
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Make sure those who will install the flood barrier are well-informed about how it works.
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Have a plan for filling sandbags or store sandbags pre-filled and ready for use.
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In most cases, you will need to complement the flood barrier with pumps. Have these ready, plan where the pumps should be placed, and ensure electricity or fuel is available.
If you are unsure about anything or would like extra help, Haawal can arrange training days, so feel free to contact us!