E470 makes further move to banish signals - new $18m 'skiers ramp' opens

E470 Public Highway Authority (E470PHA) in Denver have opened a grand new 2.33km (7645ft) long direct connector being nicknamed the skiers' ramp because it takes northbound E470 tollroad motorists way up and over the complex roadway spaghetti to head westbound on I-70 up into the Rocky Mountains. Ramp H as it is named in the highway planners' jargon is 2 lanes plus shoulders with 493m (1616ft) of steel plate girder bridging in about ten spans, the rest embankment.

It provides a splendid highspeed ride for traffic from the southeastern portion of Denver going out west. The new construct is one of two big  high direct connector ramps planned at the staged interchange, which also needs four right turn ramps (C, D, O, and K on the plan), another long left turn ramp (T), and a loop (A) before the old signalized diamond interchange above I-70 can be dispensed with for turning movements.

The major advance occurred August 2006 when they opened the twin bridging for the mainline of E470 over I-70 called the Fly By project. That slight serve west of the E470 mainline ended the odd situation on a tollroad in which traffic going straight through was subjected to a red traffic signal periodically to let turning traffic cross the opposing direction of mainline traffic.

Signalized diamond from compromise in financing

When it was first built some ten years ago E470PHA had to make some serious compromises to stretch their money and one was to make use of a simple existing diamond interchange at I-70 called Old Gun Club Road and install signals at the top of each set of ramps.

The Fly By opened some 15 months ago allowed traffic to "fly by" the old diamond but turning movements continued to use it. Now with the opening of Ramp H only three of the old diamond IC ramps are in use by E470/I-70 traffic, and they will be progressively taken out of service as additional highspeed ramps are built.

Weekly wrecks before

Signals on the mainline of an expressway standard highway like E470 are not a good idea. There were 49 crashes there in 2005 the last full year in which the tollroad relied fully on the diamond IC. With mainline traffic removed there have been only 4 crashes in the first three-quarters of 2007, suggesting a 90% reduction in the accident rate.

Opening ceremonies for Ramp H were sponsored for E470PHA by several Rocky Mountains businesses including the Ski Train, Colorado Ski & Snowboard Expo and Winter Park Resort. They organized the skateboarders.

Ramp H was installed by Lawrence Construction under an $18m design-build contract and completed on time and on budget.

TOLLROADSnews 2007-11-06