The Turning Point – Part 1: Rocky, the Big 10 and Clay

Everything up to this point has been but a prelude to the DRGW assault on the Rockies. This assault begins with the siding of Rocky (MP 18.0) at the foot of the Big 10 Curves. Rocky is a 7330 foot siding with a house track and the junction with the Rocky Flats branch. The Rocky Flats branch is the last significant industrial work east of the Moffat Tunnel. On the main line, to the west of Rocky, lies the Big 10 Curves, a series of 10-degree railroad curves (radius of about 574 feet or 43 inches in N-scale)  along the inside of a natural amphitheater and then along the outside of a bluff that allows the DRGW to gain critical elevation for its assault of the front range of the Rockies. The line which up to this point was nominally headed west, swings towards the north, then 270 degrees back through the south to the east, and then another 180 degrees to the west, before another 90 degree swing to bring it to the north, and into the 5780 foot siding of Clay (MP 21.2).

Looking over the Big 10 Curves facing southeast. That is Denver in the distance, with Clay siding in the foreground. Rocky siding is just to the left of the picture on the lower level of the loops. Photo by David Langdon.

Rocky Siding - the Big 10 Curves - Clay Siding from Google Maps.

Looking at the area on Google Maps gives another view. The main line enters from Barbara Gulch and crosses under the US Highway 36, running between Golden and Boulder, and enters Rocky Siding.

A train led by UP6773 leaves Rocky east bound for Barbara Gulch. The snow cleared out of the upper and lower loops forming the Big 10 can be seen in the background. February 8, 2012 by Cameron Turner.

UP5715 leads a train under the US-36 bridge into Rocky Siding, June 4, 2015 by Cameron Turner.

Rocky extends into the natural amphitheater, providing a significant siding for trains to pass, as well as serving the junction to the Rocky Flats Branch. That branch leaves Rocky on a 4% grade to climb to a grade crossing across US-36, and then CO Highway 72, as it heads north along US-36. Exploring the area with Google Earth in 3D yields a number of interesting views.

Google Earth View looking south west. The Rocky Flats branch exits to the lower right hand side of the picture, while the mainline to Barbara Gulch exits the lower left. The mainline headed west exits along the upper right hand side of the image.

Another Google Earth Image looking north. In this view, Barbara Gulch exits the lower right hand side, and the upper Big 10 curve is on the left side of the image.

Wrapping along the lower bowl, also called the Little 10 Curve, the mainline climbs on a 2% grade before reversing course to climb around the outside of a bluff that forms the Big 10 Curve. Trains on this bluff are protected from the high winds that can exist in the area by a set of abandoned hopper cars welded to a set of rails on the inside of the curve. Nature has overgrown many of these cars.

Installed in  November or December of 1971, a string of hopper cars filled with dirt made a suitable windbreak to protect cars from high winds in the area. Photo by Ray Kenley.

The hopper cars placed in 1971 have become the basis for a number of trees and bushes to grow in the winds. Nonetheless, the winds affect their growth as can be seen by how they lean towards the cars. Photographer Unknown.

Even the dirt in the cars has proven to be a suitable place for grasses and weeds to grow. Photo by Loco Steve.

Google Earth view of the windbreak. Here, the hopper cars are vague rectangles of foliage.

More details about the windbreak can be found here. Past the windbreak, the line turns and enters Clay siding. Originally named Fireclay for the clay mined in the area and used to make bricks, the siding name was shortened to Clay. Today, it has been renamed Eisele for a UP official. The siding is short, and thus rarely used. Furthermore, the siding itself is on "soft" ground, and hence its use is restricted to light trains. I've only seen it used for passenger trains to pass freight trains. All in all, each of these three elements are a fundamental component to modeling the area.

Cameron Turner