Machado Lake Ecosystem Rehabilitation

Our subsidiary, OHLA USA, Inc., executed a $75 million contract to improve water quality in the Ken Malloy Harbor Regional Park’s 45-acre Machado Lake. By removing contaminated sediment, installing systems to remove pollutants from incoming stormwater, and constructing treatment facilities, the project ensured continued water quality moving forward. OHLA used a hydraulic vacuum to dredge the lake to remove sediments and invasive species. The team installed hydrodynamic separators at the three primary project storm drain inflows and created wetlands throughout the job site. The crews constructed four fishing piers on CIDH piles, two fishing zones, two pedestrian bridges, an underwater capping system, and a sand habitat on the lake bottom. The scope of work also included rehabilitating a campground located within the 290-acre park. The park was landscaped with 600 new trees, and new pathways were added throughout with interpretive signs and features.

The scope of work included in-lake improvements: dredging the lake sediment and capping the lake bottom with an AquaBlok® bio-layer cap, constructing oxygenation and phosphorous removal systems, removing invasive riparian vegetation, constructing an in-lake sedimentation basin, and rehabilitating the dam structure at the south end of the lake. Storm drain facility improvements included installing five Continuous Deflection Separation® (CDS) systems at the major storm drain inlets to the lake. The vegetation, habitat, and park improvements consisted of invasive plant removal, planting of native species, park irrigation and landscaping, and installing recreational features such as fishing piers, fencing, and walkways. The scope also included improvements to the campgrounds located at the south end of the site.