Universal Studios Orlando hired Fender Marine Construction to install a water inflatable cofferdam to isolate a lagoon in order to allow for pump repair by others. Universal Orlando directed Cloud 9 Services, Inc., the parent company of Fender Marine Construction, to perform the pump repair work inside the cofferdam. We used the dewatering method to pump water away from the work area. The work was completed and the cofferdam was removed on schedule.
What is a cofferdam
Cofferdams are enclosures built across or within bodies of water to allow construction projects to take place. They can be built in many shapes and from a variety of materials. Water is pumped out of the cofferdam to allow workers to function in a clear, dry area. Due to working in the water, sometimes it will leak in or breaks may occur causing flooding. Cofferdams are designed to easily pump out any water inside the working space. After the job is done, workers dismantle the structure and the site is left clean.
Why use inflatable cofferdam
Traditional cofferdams are the basic version of the structure. They are usually made of sheet metal or wood and can be pretty expensive if the job is small. For this job at Universal Orlando, we used an inflatable cofferdam because the area was tight and smaller. Inflatable cofferdams are filled with water to inflate and keep them sturdy. This type of structure proves safer with its softer design. Traditional cofferdams use rocks and other potentially dangerous materials that may injure workers. Inflatable cofferdams are also easier to install and can be ready to use the same day as construction.
Dewatering and cofferdams
Dewatering is the process of removing ground water from an area. In this case, dewatering was used to clear the workspace inside our cofferdam. This is an especially important process to incorporate when doing repairs as water can damage the project. An inflatable uses the onsite water to fill up and as its pumped from the area, it’s returned to the original body of water. Dual tubes act as a stabilizer to keep the cofferdam from rolling due to the outside water pressure. Once the dam is inflated, the combination of weight, mass, and pressure stabilizes the cofferdam so a dry and safe job may be carried out.
Different types of dewatering
There is a variety of methods for dewatering depending on the job being done. Sometimes cofferdams are used along with their process. The methods of dredging and vacuum dewatering are two that are used frequently in construction.
Dredging is used to clean out the bed of a body of water, like a river, by scooping out mud, weeds, and other debris. Inflatable cofferdams are even utilized to provide a barrier to keep water out of the area being dredged. This process prevents debris and sediment from flowing downstream and filling channels and harbors.
The second method is vacuum dewatering. This process improves durability and strength in concrete by reducing water in the cement immediately after mixing it. This is usually done on floors. Some examples include: parking lots, industrial floors, and deck slabs of bridges.