Image: cropped frame from PACIFIC ELECTRIC RAILWAY BOOSTERS CLUB INTERURBAN TROLLEY TRIP LOS ANGELES CA RED CARS 17304e
The Railroad Boosters (now Pacific Railroad Society) were southern California railfans who sometimes chartered trips on trolleys and trains. The video at the link is from a 1939 trip they took from Los Angeles to points north of San Bernardino on the Pacific Electric red cars. At 5:32 you can see where tank cars were filled with Arrowhead water near the famous Arrowhead Hotel.
This is a silent amateur movie that offers a glimpse into the greater L.A. area. A few seconds are blank (6:10 to 6:20) followed by seemingly random shots of trolleys that may or may not have been part of this trip. In the comments section of the youtube link there are some mentions of locations seen.
This film was saved and made available by Periscope Film LLC. Learn more about them and how to support their work at https://www.patreon.com/PeriscopeFilm .