OnSite Services - Portadam Portable Dams - Common Configurations

Three-sided cofferdam

Before the invention of Portadam^®, river bridge pier inspection and any subsequent maintenance could only be undertaken by divers, or by the construction of expensive sheet piling cofferdams. Sheet piling is not always possible due to limited height beneath the bridge deck to facilitate the sheet pile driving machinery. If the bridge pier is in close proximity to the riverbank, a three-sided Portadam^® cofferdam would be the preferred configuration, allowing easy but more importantly, safe access for men and equipment directly from the bank. This configuration is also perfect for bank restoration work including wall repairs, gabion installation, surface water outfall construction/repairs.

Box or rectangular cofferdam

Where a bridge pier is situated away from the riverbank, as with a large multi-span bridge, the Portadam^® can be installed in a box or rectangular configuration, completely surrounding the pier. Access to the work area in this case, would be from either the bridge deck above, or an adjacent floating platform.

Flume Dam

When the complete damming of a section of flowing river is required, it is necessary to maintain a constant flow through the dry working area. This can easily be achieved by using two Portadam^® dams with the installation of a 'flume' passing between them. The "flume" is a continuous section of pipe that has been constructed and sealed into the dams at each end of the dry section, allowing river water to flow unabated.

Standard straight or curved dam

Where there is simply a requirement to create a temporary dam across a watercourse, river or canal, a simple 'bank to bank' dam configuration is used.

Temporary reservoirs structures or settling tanks

Because it is possible to incorporate internal 90° corners in a Portadam^® construction, we are able to create temporary tanks/reservoirs, subject to equipment availability, almost any volume subject to available level land space. These can be used to store contaminated liquids/water on site so that solids can be allowed to settle as well as provide valuable remote storage of clean water wherever required.

Emergency flood protection

Portadam^® can also be used to divert or hold back rising floodwaters from buildings and critical infrastructure, such as water treatment plants and electricity substations, in times of emergency. Portadam^® is installed and removed quicker than sandbags, enabling normal plant operations to continue with just the "skeletal" framework pre-installed but incorporating gaps to allow vehicular and personnel access. The vinyl membrane is then placed only at the very last moment.

Testing and Industry Approval

Portadam^® has been tested by the UK National Physics Laboratory, as well as extensive laboratory and field testing by the U.S. Army Corps of Engineers. Of the U.S. systems tested (Portadam, Sandbags, Hesco Bastion, RDFW – Rapid Deployment Flood Wall, Flood Walls and Metalith H20), Portadam was regarded as the all round best performing system.

The U.S. Army Corps of Engineers report is available to download on their website www.erdc.usace.army.mil/

Team Training

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