The Allen-McColloch Pipeline (AMP) is a key component of the Metropolitan Water District of Southern California (MWD) regional water system, spanning 26 miles to supply treated drinking water to the Municipal Water District of Orange County and its retail agencies. Constructed in the 1970s, portions of the prestressed concrete cylinder pipe need to be relined to ensure future water reliability.

In a recent inspection, MWD identified distressed segments of the pipeline that require urgent repairs. The initial phase of work will rehabilitate approximately 2,200 feet of pipeline located in Irvine, specifically in the Orchard Hills and Portola Springs communities, and in Lake Forest.

Construction is scheduled to begin the first week of March and continue through May. Twenty-four-hour work may be necessary, and residents may hear noise due to construction, excavation, ventilation, and equipment. Residents may also notice additional construction vehicle traffic in the area. Residents' water service will not be disrupted. 

The activities for the week of March 4–March 8 include:

• Mobilize equipment into the locations, which includes the Excavator, Lodrill, Water Buffalo, Gang Boxes, Plates, Beams, etc.
• Survey/Stake pipe cut lines and portal locations
• Pothole pipe and confirm shoring
• Receive and set up construction trailers
• Install temporary power
• Clear and grub
• Install Portal fencing/sound wall

Activities for the week of March 11–15 include:

• Install pipe and dirt ramps over existing V-ditches
• Install Best Management Practices (BMP’s)
• Survey and stake beam locations
• Drill and install beams and plates

For additional information, visit MWD's project website and click on The Allen-McColloch Pipeline Urgent Repair or email communityrelations@mwdh2o.com.