I-270 Innovative Congestion Management (ICM). Montgomery and Frederick Counties, Maryland.
WRA developed the project goals, evaluation criteria, performance metrics, and procurement documents. We were responsible for the independent review of all traffic elements including traffic control devices, ITS elements and maintenance of traffic of each of the 17-individual design packages to ensure the design-build team’s plans complied with the RFP documents. WRA also prepared independent detailed cost estimates. These estimates were used as a basis for cost comparison at 30%, 65%, and 100% design completion covering all disciplines (MOT, earthwork, drainage, SWM, ESC, pavement, shoulders, landscape, and traffic) for the ramp widening, ramp metering and active traffic management system packages.
WRA’s GEC services during construction included technical reviews, over the shoulder reviews, plan and specification reviews, independent cost estimates, meetings, and coordination.
WRA developed the calibrated VISSIM model that was provided to prospective design-build teams. This model was used to populate the performance metric evaluation criteria template, which was over 200-pages. The metrics were travel time, speed, density/level-of-service, intersection operations, queue lengths and vehicle throughput. The VISSIM model and performance metrics were used to assess if the congestion relief improvements achieved the expected outcomes once constructed.
This project proposed the first ever Active Traffic Management (ATM) and ramp metering systems in Maryland. WRA assisted MDOT SHA in the review of the ATM and ramp metering concept of operations, interface control documents, and selection of qualified vendors to provide software development to operate the I-270 ICM intelligent transportation system technology.