Silt Pond and Spillway Renovation

Client: City of Lake Tapawingo, Missouri

Increased development combined with minimal maintenance over the last 20 years reduced the effectiveness of the three silt ponds upstream of “B” cove at Lake Tapawingo, Missouri.  The Lake Tapawingo Development Company asked Affinis Corp. to develop a restoration plan for the silt ponds as well as improve Beach Drive located on the dam of the downstream pond.  During the schematic design phase, our engineers completed hydrologic and hydraulic analyses of the existing 131-acre drainage area, evaluated three improvement options, developed a phased-construction plan, and prepared opinions of probable construction cost for each alternative.

Because it provided the most effective means of sediment control and peak flow reduction, the Development Company’s Board selected the improvement option that combined the two lower existing ponds into one pond, used the upstream pond for sediment control, constructed a triple, 8-foot by 2-foot reinforced concrete box bridge at Beach Drive as an emergency spillway, and constructed a baffled-apron spillway to slow runoff velocities entering “B” cove.

Affinis provided survey, design, legal descriptions, permitting, and as-needed construction observation services for the project.  We also attended homeowners’ meetings and board meetings.

SIGNIFICANT DESIGN ITEMS:

• Hydrologic and hydraulic analysis
• Alternative analysis
• Property and topographic surveys
• Structural design
• Erosion control and water quality improvements
• Public information

COMPLETION DATE: 2007

COST: $294,000

PROJECT PHOTOS (Click to enlarge)

UNDER CONSTRUCTION