Transportation officers have been busy attempting to undo the knot that’s rush-hour gridlock on Interstate 25 south of Denver by testing a tech-heavy and precision-based site visitors administration strategy — and the outcomes are in.
With CDOT’s coordinated ramp metering system in full operation, afternoon commuters saved 2.5 minutes on common in journey time driving the 14 miles from Ridgegate Parkway in Lone Tree to College Avenue in Denver. That was a 14.3% enchancment over the time spent traversing that stretch of I-25 earlier than the know-how was turned on.
The distinction was even sharper throughout the heaviest hour of the night commute, with drivers chopping off greater than 4 minutes in journey time between Douglas County and Denver — a 19% enchancment in journey time from earlier than the Good 25 Managed Motorways Pilot Program launched final yr.
Morning rush-hour outcomes had been much less spectacular, with a median 2% time financial savings for commuters throughout the a.m. peak in comparison with pre-pilot situations.
The pilot ran final spring and summer season on the northbound lanes of I-25 and officers on the Colorado Division of Transportation have been deciphering the outcomes since.
“These programs have the power to significantly enhance the effectivity of freeway networks,” mentioned Ben Kiene, a site visitors operations engineer with CDOT. “There’s much less cease and go. You’ll decelerate however speeds get better.”
Now the trick is making the know-how — which makes use of real-time software program algorithms to exactly management the intervals at which autos enter the interstate from on-ramps right down to fractions of a second — everlasting and extra widespread.
“There was sufficient there that we wish to discover increasing additional,” mentioned Angie Drumm, CDOT’s metro Denver deputy director of site visitors and security. “So as to develop it, it could require funding within the detectors and controllers that management our ramp metering.”
However that requires cash. CDOT is making use of for a $1.5 million federal grant that might enable it to plan for a good larger implementation of the coordinated ramp metering know-how — presumably all the way in which from Lone Tree as much as Thornton.
It’s a $50 to $60 million proposition however the payoff in journey time financial savings may very well be large, Kiene mentioned. That’s as a result of the effectivity of site visitors circulate from the fixed and minute manipulation of the time automobiles wait on entrance ramps earlier than merging onto the freeway is amplified as extra ramps are integrated and extra knowledge about situations down the highway are folded into the system.
“If we had been in a position to implement this throughout a a lot bigger system, you could possibly have actually important outcomes,” he mentioned.
That was confirmed in Melbourne, Australia, the place the coordinated ramp metering strategy was utilized throughout a a lot wider space than 14 miles of Denver’s southern suburbs. The outcomes gathered on the M1 freeway had been spectacular: The variety of autos getting via elevated by 25% throughout peak commuting intervals, journey speeds improved 35% to 60% throughout peaks and crashes went down by 20% to 50%.
Justin Schmitz, director of public works and mobility for Lone Tree, praised the pilot program for bettering site visitors situations on I-25 final yr. As as to whether tighter management of car actions on on-ramps bled over to elevated stacking on the town’s streets close to interchanges, Schmitz mentioned that was an issue the town needed to cope with.
“Probably the most important space impacted was on northbound RidgeGate Parkway,” he mentioned. “The challenge workforce labored all through the pilot to enhance queueing situations to reduce the impression of that spillover.”
However with development within the southern tier of the metro space persevering with at a strong tempo, Schmitz mentioned CDOT has to strive what it could to enhance the circulate of site visitors.
“Persevering with to spend money on sensible know-how such because the metering know-how on the I-25 hall is essential as density on this a part of Colorado will increase,” he mentioned. “Working to enhance journey experiences in and across the Metropolis of Lone Tree aligns with our organizational objectives as nicely.”
CDOT’s Drumm agreed, saying there isn’t a quick prospect of widening the closely traveled roadway via the Denver Tech Heart.
“Increasing capability is just not in our 10-year plan,” she mentioned. “That is a technique we might assist.”
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