In the early morning hours of December 25, 2008, a 48-inch prestressed concrete cylinder pipe (PCCP) water transmission line failed under a major state highway in the southern part of Houston, Texas. The failure flooded the nearby area with water depths up to four feet and closure of Almeda Road. Service was maintained in the area due to multiple groundwater wells operating for the concurrent planned shutdown of the Southwest Pump Station refill line.Lockwood, Andrews, & Newnam, Inc. (LAN) and a local utility contractor were contacted by the City of Houston (City) Utility Maintenance crews to assess the extent of damage and restore the water line and roadway to service.Condition Assessment of the PCCP portions of the W. Bellfort 48-inch included visual observations of pipe interior, limited observations of pipe exterior, electromagnetic survey and materials testing.The failed PCCP pipe section was removed along with three adjacent pipe sections and replaced with approximately 64 LF of a 48-inch steel pipe. This paper will present the findings and conclusions of the Assessment as well as discuss measures taken to restore the roadway and water line to service quickly over the weeks between Christmas and New Years.FAILUREAt approximately 1:45am on December 25, 2008, the City of Houston received an unexpected Christmas present. A drop in system pressures at a major pump station was the first sign that a 48-inch prestressed concrete cylinder pipe (PCCP) water transmission line had failed. The failure resulted in backfill washed out under Almeda Road, a major state highway near the Reliant Stadium and Texas Medical Center, as shown in Figure 1.
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