Embed Size (px)
Citation preview
March 27, 2018
City of Raleigh Neuse 72-inch Parallel Interceptor Condition
Assessment and Rehabilitation
Jim Perotti, PE CDM SmithBreanne Long, EI CORPUD
Presentation Outline
Interceptor History Inspection Approach Condition Data Results Data Evaluation
Neuse Parallel 72-inch Interceptors
History
Transport 40 MGD South Interceptor - 1973 North Interceptor – 1998 Class III and IV RCP with a
coal-tar epoxy liner
History
2014 Pole Camera Inspection Some sections installed in land
bridges (culverts laid in cut section, backfill, install pipe in cradles, minimum cover)
16-inch DIP Reclaimed water line installed between 72’s
Inspection Approach
Manned-entry• 4 man crew
‒ 2 men in pipe
Inspection Approach
Manned-entry• 4 man crew
‒ CCTV at entry MH
Inspection Approach
Manned-entry• 4 man crew
‒ Forced air at exit MH
Field Health and Safety Plan
Daily emails to project teamlocation/nature of work, weather outlook, status of lockout/tagout
Daily maps sent to Fire Dept • Work locations – road names,
manhole #s (address location not always available)
• Directions to nearest hospital
Field Health and Safety Plan
Doorhangers• 72 hours in
advance
Field Health and Safety Plan
Push Cart• 4 gas monitor, tools, 20
minute supply of air
CCTV monitoring WhatsApp
Inspection Approach - Manholes
Pre-screening of pipe conditions and debris levels
Inspection Approach - Pipes
Diameter laser measurements –at MH and every 25 feet
Pipe soundings every 10 feet Penetration tests
Bypassing Efforts
Walnut Creek PS
Bypassing Efforts
Battle Ridge
Bypassing Efforts
Battle Ridge
Hwy 50 Force Main
Bypassing Efforts
Hwy 50
Bypassing Efforts
Gravity Lines• 8-inch to 12-inch • Small trash pump with flexible hose • Allowed to enter 72
Condition Assessment Findings
Condition Assessment Findings
Modified PACP
Condition Assessment Findings
Effects from FM
Cleaning Efforts
Last 4000 feet of each section contained up to 12-inches of debris
Cleaning Efforts
Cleaning Efforts
Cleaning Efforts
Cleaning Efforts
Cleaning Efforts
Plant Influent Channel
Structural Evaluation
Pipe wall type assumptions• Type A for Class III and Type B for Class IV• 1-inch cover to reinforcement
Max burial depths for each section
Road crossings encased
Structural Evaluation
Structural Evaluation
Structural Evaluation
Rehabilitation Alternatives
Alternatives Pros ConsPotential Bypassing
Needs
Estimated Cost (based on 18,000')
Slipline (FRP) Little DisruptionInstalled in Ex. Flow
Reduced Capacity,Intermittent size
changesNone $600/LF
Open Cut (FRP)
Full CapacityFully Structural
Lengthy Disruption,Land Bridge & Major
Road X-ings
Full 72" bypass $700/LF
CIPP Little DisruptionMaintain Capacity
Not Fully Structural in all reaches,
On-site WetoutNone $1,100/LF
