Folsom spillway megaproject began as 3D printed model

Published Feb. 8, 2016

SACRAMENTO, Calif. – In 2017, the U.S. Army Corps of Engineers Sacramento District will complete one of its largest and most complex dam projects—the Folsom Dam auxiliary spillway.


Folsom spillway scale animation

How big is the Folsom Dam spillway? An animation shows the approximate scale of the spillway control structure in comparison to the height of a human and the statue of liberty.


But before engineers even began constructing this colossus of concrete and steel, the main components were prototyped using 3D printing technology.


 Dogging assembly - then and nowAn animation shows the dogging assembly as a 3D printed model and the full-scale steel structure in operation today.

 Control structure - then and nowAn animation shows the control structure as a 3D printed model and the full-scale structure today.


A short video produced three years ago showed the basic process of designing and 3D printing one of the secondary dam’s components, a dogging assembly.


Corps modeling manager Kevin Russ explains the 3D design and printing process for the dogging assembly model.

Today, the dogging assembly is fully constructed and operational. The assembly is a manually operated steel tube that locks the main control structure’s massive 105-ton bulkhead gates in the open position so dam maintenance operators can safely work on the structure.


Corps civil engineer Cheuk Wan explains the purpose and operation of the dogging assembly.

“3D printing has really helped the way we design projects and made it a lot easier to conceptualize unique dam components like the dogging assembly”, said Cheuk Wan, Sacramento District civil engineer. “We were able to physically see if everything worked and moved correctly before we started full-scale construction.”

I know what you’re probably thinking, “Can engineers 3D print the full-scale dam?” We’re not there just yet, but 3D printing has revolutionized the way the Corps prototypes important flood risk reduction projects like the Folsom Dam auxiliary spillway, and they already have plans to use this ever-evolving technology in upcoming infrastructure projects.


 Isabella Dam 3D labyrinth weir

A 3-dimensional computer sketch shows the planned structure for the Isabella Dam Safety Modification Project's labyrinth weir. Engineers will use 3D printing to prototype several components of the project before construction.