Westlake Lake Management Association


Private HOA Dredging, Dewatering & Disposal

Westlake Lake Management Association (WLMA), a nonprofit organization that maintains the lake in Westlake Village, underwent a first ever, high-tech lake dredging procedure by means of a mobile treatment plant. The lake opened in 1968.

The dredging, being done by JND Thomas Company was necessary due to the accumulation of sediment and other debris over the years. Most of the sediment and other trash came from storm drains and from the growing number of developed lots that produced an erosion of topsoil over the years. David DuVarney, lake operations manager, said that most of the material being removed is on the Ventura County side but added that workers are dredging the entire lake. "The fish, along with the turtles scatter far away from all the commotion the dredging creates. They are perfectly safe." The dredger works like a giant vacuum cleaner that sucks up sediment and debris and then pumps it through a pipeline to the mobile treatment plant. Unwanted materials are then filtered out while preserving the water which is returned to the lake. After the dredging is complete, the lake will not only be cleaner, but it will also be deeper, providing a better environment for the lake’s wildlife.


JND deploying a maintenance dredge, floating pipeline, a booster pump and a portable mechanical dewatering plant for processing lake sediment. Approximately 80,000 instu cubic yards of material was removed at 2,500 gpm thru 6,000 feet of pipeline in a continuous “closed loop” system. All dredging operations were performed under direct supervision and in compliance with all local, state and federal regulatory agencies consistent with issued permits. The dewatering aspect of the project was located adjacent to the lake with NO sediment ever coming into contact with the ground. The dewatered sediment was directly conveyed into trucks where it was hauled to the disposal sight. All water used from the lake during the dewatering process was returned back to the lake under the 30 ml per liter permit requirement. No noise complaints.



Relevant Project Elements

  • Hydraulic Maintenance Dredging at an Active Recreational Facility
  • Mobilization and Demobilization of a Mobile Multi Component Dewatering Plant
  • Full Compliance; Storm Water Permits, Regional Water Quality & Air Resources Boards
  • Continuous Operation of Multiple Engine Driven components within minimum “Noise” level
  • Return Water from Dewatering Operations Averaged 19ml per Liter