North Shore of Lake Tahoe, CA Boat Ramp Repair – 2003
An 8' high AquaDam® starts off from the shoreline with a walkway built over the top of it. The start of the AquaDam® extends up the wall and onto the walkway. This is an 8' high x 50' long close-ended AquaDam® with an attachment collar. The AquaDam® is partially filled. You can see the pump in the top middle part of this picture. When starting make sure the ends are elevated higher than the maximum height of AquaDam® after it is fully inflated.
The sides of this AquaDam® were folded in, during manufacturing, for transportation purposes. This unit was unrolled by hand and not by internal water pressure. This allows the AquaDam® to float so it can be moved into the exact location necessary. The sides will unfold out later when inflated with water.
The first AquaDam® is now ready to receive the next AquaDam®. Multiple connections are used here to achieve the require length. You can see the end of the collar (black) in the water at the end of the AquaDam®. The other half of the collar is around the last 20' of the AquaDam® that has been inflated with water.
An 8 foot long x 100 long AquaDam is unrolled by hand down the boat ramp and out into the water. The black inside fill tube portions are shown here folded back over the top of the white AquaDam. Now the AquaDam will float and can be moved in position to make a connection.
The second AquaDam® is being moved into place so that it can be inserted into the connection collar of the first AquaDam®. Each AquaDam® has the same dimensions, one is white and the other black.
The black inner fill tubes have been inserted up through the top of the connection collar. Blue discharge hoses have been inserted into the fill tubes and down past the hole cut into the top of the connection collar. The hose has to be past this point. The remainder of the black fill tube will be sucked back down into the cavity during the filling process. The end of the first AquaDam® is used as a platform to set the pumps on. The water used to fill the AquaDam® is pumped directly out of the lake.
Because of water quality concerns (dirty water) the client's permits called for a floating, silt boom curtain with a chain (yellow) to surround the entire project for additional protection measures. The white AquaDam has to make a rounded turn towards the end. The attachment collar is folded up on the end of the AquaDam. A rope is around the middle of the AquaDam is causing a funny indentation in the corner where it bends.
After the AquaDam® has been inflated pumps are moved out to the end so an additional AquaDam® can be attached. The black part of the AquaDam® in the picture is the attachment collar from the end of the first AquaDam®. The bottom right-hand corner shows the two black inside tubes protruding up through the black outside material which makes up the attachment collar. All of the boat walkways have been moved to one corner of the marina. The client's permit did not allow for that portion of the marina to be excavated.
The third AquaDam® (black) has been attached to the end of the second AquaDam® (white). The third AquaDam® abuts into a wooden bulkhead. The water-filled cofferdam is complete. Notice the portion of AquaDam® along its side that is pushing on the entrance to the marina wall.
The connection collar is white. The fill tubes are clear, making them appear white. They come up through the top of the connection collar. The third AquaDam® bends in an arc back to the shoreline. AquaDam's are very versatile and can bend around the metal sheet pilling. This area was the deepest (approximately 6 feet.) However, this portion of the AquaDam® did not make a good seal because of the bend.
This entire boat ramp needed to be replaced and the area out to the AquaDam® was to be excavated of its fill material, deepening the marina.
This is the actual boat ramp below water level. It is over 50 years old. It has been patched together over the years. You can see the fine silt that surrounds it which is scheduled for excavation.
The water has been pumped out, revealing the poor condition of the boat ramp and surrounding walls. All of this area is scheduled for new construction.
You can clearly see the sandy muck and other obstacles that were a hindrance to the effective operations of the marina. The owner of the marina was not satisfied with the AquaDam's claiming there was too much leakage under the AquaDam® and decided to call off the project. The discharge of water over the top of the AquaDam® and into the greater Tahoe Lake was deemed unacceptable by the client. Aqua Dam, Inc. (before installing the AquaDam's) stated to the client that seepage would occur under the AquaDam (and into the work area) and that dewatering pumps would need to run to have a continually dry work area.