There are several major components associated with undergrounding a 500 kV line. The majority of the work will be completed using a method called “trenching.” Trenching generally refers to digging or excavating, which will be conducted with use of large construction equipment in order to install the electrical transmission facilities underground.
Most of the trenching work will be conducted within the utility right of way corridor. However, at times, Southern California Edison (SCE) crews will trench across residential streets and significant thoroughfares through the city, including Chino Hills Parkway and Pipeline Avenue. Construction activities may require periods of road and/or traffic lane closures.
The duration of the temporary lane closures will vary depending on the location:
- At most residential streets, SCE crews will temporarily close half the street during construction and upon completion, the second half of the crossing will be constructed. This work typically takes approximately ten working days per residential street.
- On Cork and Lobelia Drive, SCE crews will implement full street closures during construction working hours. This work will take approximately 15 working days per street to complete. (Note: at least one street, Cork or Lobelia Drive, will be open at all times).
- At Chino Hills Parkway, there will be two sessions of trenching work. The first session will take approximately 45 days to complete. Upon completion of the first session, crews will move to the next location while they allow the material to cure for approximately 30 days, at which time all lanes will be open. Then crews will return to complete the trenching work for a duration of approximately 45 days. This will, again, require lane closures.
- At Pipeline Avenue, this work can take up to 30 days.
Approximate hours are: Mon–Fri: 7:00 am–7:00 pm, and Sat: 8:00 am–6:00 pm. At Chino Hills Parkway: 8:30 a.m. – 7:00 p.m. Mon – Fri.
SCE understands that construction may be disruptive to daily activities of residents and area businesses. We are committed to minimizing impacts and ensuring safety of the public and project personnel during this work. Please visit the “More Information” tab on this web page for valuable information to help keep you safe when around construction areas.