A pipeline that spans almost the entire length of San Diego County is back in use after engineers spent weeks patching a massive crack in the pipe’s infrastructure.

The San Diego County Water Authority (SDCWA) discovered a leak in September to a portion of its 90-inch Pipeline 4, which has carried water since 1966 from the Skinner Water Treatment Plant near Temecula down to the Otay Reservoir near Chula Vista.

NBC 7 was the only news media outlet invited inside the pipe in September before repairs began. The pipeline was shut off Sept. 16 with the cooperation of the Water Authority’s member agencies.