Sediment (muck) removal from larger lakes is performed when the accumulated sediment has an adverse impact on the planned use or appearance. Sediments are commonly removed to:
Restore recreational access for leisure boating, swimming, and fishing
Regain lost storage capacity in water supply reservoirs
Remove nutrient-rich sediments
Remove toxic substances
Reduce rooted aquatic plant growth
Lessen sediment re-suspension by winds and waves
Improve the fish habitat
Once a decision is made to dredge, the options are:
|Drain and Excavate||Mechanical Dredging||Hydraulic Dredging|
|The lake is drained and heavy equipment is used to excavate the sediment. This method requires access for heavy equipment to haul away the sediment. This is the least expensive method, but takes the longest time to accomplish. It has the greatest environment impact and is susceptible to rain delays.||This method removes lake bottom sediment from the shoreline using drag lines or long-reach excavators. The lake is not drained. The shoreline is leveled for the heavy equipment to work and access is needed for heavy equipment to haul away the sediment. This method is limited to 50-100 feet from the shoreline.||Hydraulic dredging uses a floating platform with a pump that vacuums sediment from the lake bottom. Sediment is pumped through a temporary pipeline to the shore. The sediment and water are separated at the final destination and the water is returned to the lake. The most cost effective approach to separate the water and solids is to construct a temporary settling basin.|
Muck Doctor uses the Hydraulic Dredging approach. The dredge floats on the water and pumps the muck through a temporary pipeline to an onshore settling basin. Muck can be pumped for thousands of feet. The dredge removes sediment very precisely using GPS tracking.
The Muck Doctor hydraulic dredging approach uses a discharge line and possibly a return line. These are the only disturbances to the surrounding environment. Other than these lines, the dredge is the only machine to be seen. It is an unobtrusive method that does not require disturbing the shoreline and requires one trip in to put the dredge in the water and one trip out when the project is complete.
When the dredging is complete the sediment has dried, it can be leveled and seeded. It can also be transported and used as an organically rich fill. Dredging improves water quality by reducing the nutrients available from the sediments. This reduces nuisance algae blooms. Deepening the lake also allows thermal stratification to develop which limits nutrient movement from deep-water areas to the upper waters.