The 30th Street 20a Transmission Undergrounding project provided a safer, more reliable energy source for the people of San Diego. The largest span of utility undergrounding in the history of San Diego, the project entailed converting a 20,304 foot-long 138kV electric transmission line from overhead to underground. The project also represents the highest voltage transmission (138kV) ever converted in San Diego.
The project earned the American Society of Civil Engineers (ASCE) San Diego Section Outstanding Civil Engineering Project Award for energy facilities.