Movie showing development of storm drain tunnels (gravity mains only) in Los Angeles from 1890-1910, focusing on portions of the Ballona Watershed (Koreatown and West Los Angeles) and the Los Angeles River watershed (downtown Los Angeles). The Los Angeles River is visible as a blue line running vertically in the right side of the image, and the beginning of the open channel of the Ballona Creek as it exists today is visible as a narrow blue line extending horizontally from the left side of the frame. The different widths of the blue lines showing storm drain tunnels is representative of the sizes of the drains themselves, which range in size from approx. 1.5 feet in diameter up to 24 feet wide in the area shown here.
Until the early 20th century, Ballona Creek and its tributaries were open perennial streams extending through much of this area west of the 110 Freeway, and many of the early tunnels constructed were built around those natural channels.
Note: This visualization is based on cartographic data from Los Angeles County. Because of gaps in the attribute information in that data, this shows only about 75% of the total mileage of storm drain gravity mains in this region; however the general distribution is representative of the total extent that exists today, and this this animation of development over time is broadly accurate in its representations of the general patterns of this infrastructure development. Data visualization created by Steve Duncan, 2011.