Project Name: Intrenchment Creek Viaduct Rehabilitation

Over 100 years old, the Intrenchment Creek Viaduct is a 48-inch pipeline that conveys sanitary sewer flows to the Intrenchment Creek Water Reclamation Center.  The pipeline was constructed as a cast-in-place, reinforced concrete viaduct structure to create an elevated creek crossing.  The aerial portion of the structure span is approximately 300 feet and is 40 feet above Parker Creek.  Over time, the viaduct has developed structural deficiencies and currently has evidence of severe cracks in its wall foundation that warrant repair/rehabilitation to restore the structural integrity of the pipeline. 
 
The scope of this project includes: 
Phase 1: Conducting a structural evaluation, surveying, and non-destructive testing of the viaduct: 

•   Determining the size, strength and reinforcement of supporting structure 
•   Completing as-built survey of the viaduct and the retaining walls  
•   Determining the remaining strength of the concrete cover around the pipe and rebar 
•   Determining the size of the foundations supporting the structure 

 
 
Phase 2:  Rehabilitating the viaduct as needed:  

•   Installing either a Cured-in-Place pipe (CIPP) or PVC Spiral Wound Liner 
•   Inserting a fiber glass pipe into the existing sewer 
•   Grouting the annular space between the existing structure and the new pipe

 
 
Justification: 

•   Enhances flow capacity of the viaduct 
•   Reduces Infiltration/Inflow or extraneous flows into the sewer system 
•   Contributes to reductions in sanitary sewer overflows 
•   Provides adequate conveyance capacity for existing and new customers 

 
Project Type: Wastewater Collection 
Proposed Project Start: 05/03/2017
Proposed Construction Start:  05/02/2017
Scheduled Completion: 12/15/2020  
Project Budget: $950,000 
Council District(s): 1, 2, 3, 4, 5 
NPU(s): E, J, K, L, M, N, O, S, T, V, W, Y, Z  
Project Status / Phase: Complete / Construction