DCCM was contracted by the Houston Country Club to provide engineering services for the channel slope repair on the south bank of Buffalo Bayou (HCFCD Unit No. W100-00-00) along the golf course fairways of holes 8 and 10. The project was previously designed by another firm and partially constructed but never closed out due to channel bank failures associated with a deep geotechnical failure below the slope. DCCM and contractor, BRH-Garver, as well as a geotechnical consultant, Professional Service Industries (PSI), and developed a structural solution with closely spaced drilled shafts to stabilize the failed channel slopes and to prevent future channel bank failures.

The project consisted of two separate stretches of bayou being repaired. For one alignment, we performed a slope up from the existing bench and lower the top of bank. For the other channel section, DCCM added a variable height wall to be able to match the existing top of bank. The limits of the channel repair work was 1,225 feet along the fairways of hole 8 and 850 feet along the fairways of hole 10 for a total distance of 2,750 feet.

The scope of services included the following:

• Designing the structural elements required to establish a stable slope system
• Coordinating the design and details of construction with the design/build contractor and the owner’s representatives
• Coordinating with PSI geotechnical engineers for a design of a stable slope system
• Preparing plans, specifications, and estimates (PS&E)
• Preparing hydrologic and hydraulic (H&H) impact analysis report
• Obtaining applicable signatures and permits from City of Houston and Harris County Flood Control District (HCFCD)
• Issuing a Letter of Map Revision at project completion
• Preparing as-built construction documents to finalize City of Houston and HCFCD permit requirements

As a result of teaming with a local geotechnical firm, a deeper global failure was discovered at the location of the failures. A previously unknown slickenside soil layer was encountered at a depth below previous project borings. DCCM resolved this problem by extending drill shafts below this layer of weakened soil immobilizing the failure.