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“First In the Nation”
Diverging Diamond Interchange
IS 44 and MO 13 - Springfield, MO
Joseph C Rickman, PE, ACTARDistrict Traffic Engineer
MoDOT – Springfield Region
Kansas & I-44, 2008
Kansas & I-44, 2008
Norton Rd. 681 ft’
Evergreen 296 ft’
Basic Interchange Problems
Congestion15-30% left turns10-15% HGVClosely spaced signals
Crashes Pedestrian
Accommodations
Congestion
Concept Design of the DDI
VISSIM Model
inVISION Studios Simulation
Opening Day – June 21st, 2009
Opening Day Signal Timing
Interchange still under construction Norton Rd Autoscope System failed No Evergreen Rd signals due to
construction Time Travels run each plan throughout
the day
Finishing the DDI
Islands installed Pedestrian buttons added Temporary signals moved from gores Permanent advanced signals added in
islands
July 7th, 2009
Pedestrian Access
Pedestrian Access
Project Timeline
Construction began: January 16th, 2009 Lane restrictions on bridge: March 4th, 2009 Traffic moved to DDI: June 21st, 2009 Construction completed: July 7th, 2009 Last modification: August 25th,
2009
Final cost: $3.2 million
Operational EffectsSuperload on March 3, 2010
Operational Effects
AccidentsTotal Reduction 24% (50% between ramps)Injury Reduction 50%
Congestion removed on the bridge Consultant Performance Evaluation
(HDR)
Public Perception
MoDOT survey of 8 zip codes 400 sent, 75 returned
The Right Solution – 89.4%More Convenient – 95.1%Less Congested – 95.2%Safer – 96.7%
