For the last couple months, I've been talking about dredging a lot because this winter we'll be taking on the task of dredging the sediment from Club Lake behind the LEC and tennis courts. I've talked about the two ways to dredge...one is mechanical, which is the use of excavators. The other is hydraulic dredging, using the machine below. These photos were taken on Mirror Lake today. I got excited because the equipment was sitting as is, and gives you a better idea how it works.
The barge below, has a boom device in front of it that does two things. It disturbs the sediment as it rotates and at the same time, it pumps the water and disturbed sediment to a near by dewatering bag, shown above. These 60' x 100' bags grow to a height of about 6' tall when full of sediment. The water drains from the bag while the sediment is contained within. After a period of 1 week, the bag can be cut open, and the sediment hauled off site, in a dry state. It's my opinion, that this will be the best method for dredging our lake. The fact that we don't have to drain the lake is the primary reason. While we don't irrigate turf over the winter months, irrigation is used during the months of November and March. We can't risk not having irrigation water available during those shoulder months. The process of mechanically dredging the lake, will require the lake be fully drained. I'm not convinced there is enough time in the winter to mechanically dredge that portion of the lake.
The tentative plan is to start by November 1st, and finish by the new year, before the lake gets into freeze/thaw cycles. I'm currently working with a company in Charleston, SC who specialize in this work. Numerous sediment samples have been analyzed by a lab in Florida to be sure the composition of our sediment can be handled by this machine. This has been a fun project so far because I've learned more about this kind of work than I ever could have imagined. For those that know me, I love to learn new things. Stay tuned for more information as I learn more!
