I-64 Embankment Study
Volkert, Inc. &Schnabel Engineering Consultants, Inc. for
the Rivanna Water & Sewer Authority
I-64 Embankment Study
• Hydrology/ hydraulic study
• Geotechnical evaluations
• Hazardous spill risk analysis
Site Location, Properties, Land Use
The Rocks LLC
City of C’ville
City of C’ville
Proposed Normal Pool
Existing Upper Dam Existing
Lower Dam
Proposed Dam
I-64 Drainage Areas & Flow Paths
Proposed Normal Pool
8’x8’ Box
Proposed Ped Bridge & Boom
8’ x 8’ Box Culvert Profile
683
675
683695
702
• Modeled 5 hydraulic conditions for 8-ft-by-8-ft box:– Existing– Repaired – 72-in liner with full reservoir– 72-in liner with low reservoir– Blocked
• All conditions acceptable
H&H - Summary
I-64 Embankment, South Side
Embankment Stability Analysis
Condition Calculated Required
Proposed Normal Pool Balanced 1.55 1.5 Acceptable
100-yr Flood Unbalanced
(Culvert Clogged)1.52 1.3 Acceptable
Rapid Drawdown 1.54 1.1 Acceptable
Seismic 1.31 1.1 Acceptable
Settlement
• Tendency for Heave– Resisted by > 100ft of overburden
• Predicted Settlement = 3½”– In line with previous evaluations– Occurs gradually (est. 3 yrs)– Minimal dif. settlement: gradual and uniform
Geotechnical - Summary
• Modeled I-64 embankment considering:– Stability– Settlement– Seepage– Seismic
• All conditions acceptable
Hazardous Spill
• Risk Mitigation analysis
• 2 steps recommended– Floating boom– Filter curtain
Boom
Curtain
Boom
Conclusion
With proposed upgrades, I-64 embankment and culvert will function safely and adequately in conjunction with the proposed dam.
QUESTIONS?