60” x 70” Semi-Elliptical Sewer

Project Location
Culver City, California.
Construction cost
$3,742,000 - $1,000/ft
Construction Start/End
06/1997 - 06/1998


When was it constructed and how long has it been in service:
Cast-in-place construction in the early 1900’s.

Diameter of line, sewer pipe material (RCP, MCIP, brick, etc.), length of rehab portion: 60” x 70” Semi-Elliptical Sewer made of unreinforced concrete

Depth of pipe:
5 to 20 feet to crown
Depth of ground water:
No ground water
Health and safety:
Used conventional confined space entry program
Has any re-inspection been performed? What was the condition of the pipe?

Steve Nakaido, P.E.
Collection Systems Engineering Division, City of Los Angeles
Telephone: 213-847-8430


Ventilation and odor control used:
Fresh air pumped into pipe at upstream manhole, and suction fan at downstream manhole to provide adequate ventilation during the work periods. Odor control of exhaust air as required by City.
Rehab method used:
Danby Panel Lok with full annulus grouting with cementitious grout with minimum compressive strength of 5000 psi. Panel Lok flat panels arched from “J” strip anchors at invert corners. No lining of invert.
Cleaning method used (if required) and who cleaned the line:
High pressure (10,000 psi) water blasting performed by the Danby licensee (Stacy & Witbeck, Inc.).
Method of flow bypass or diversion, if used:
Full bypass pumping of 21 MGD flow.


Problems encountered during construction:
Initial specifications required monolithic grouting that, in turn, required formwork. Use of wood forms impeded cooling at the PVC surface resulting in excessive temperature differential across the grout thickness that resulted in cracking of the grout (high cement content produced high heat of hydration). Removal of forms and stage grouting resolved the problem. Grout cracks repaired by injecting epoxy grout.
Problems encountered after construction: