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Table ES.2. Percentages for Semi-Variances (SVs) for Each Regime on the I-5 Facilities County Route Regime Normal Demand Weather Special Event Incident Regime Total SV Facility Total Orange I-5 Uncong 2% 0% 2% 1% 1% 6% 100% Low Cong 9% 0% 5% 1% 3% 18% Mod Cong 13% 0% 6% 4% 5% 27% High Cong 28% 0% 12% 1% 8% 49% I-5 Totals 52% 0% 24% 7% 17% 100% SHRP 2 Analysis Tools After examining the contributions of nonrecurring events to reliability on the facility, the study team tested analysis tools from three different projects: ⢠The Reliability Analysis Tool developed under Project C11 is a sketch planning tool intended to help users incorporate reliability analysis into a standard benefit-cost framework by providing estimates of reliability impacts and monetizing those impacts using a reliability ratio and a value of travel time. The tool also provides a simple method for estimating the reliability impacts of projects. ⢠The Project L07 Analysis Tool is designed to analyze the effects of highway geometric design treatments on nonrecurrent congestion using a reliability framework. The tool has built-in, custom algorithms for modeling 16 treatments using relatively simple input data on the treatment effects and cost parameters. The algorithms are based upon work done in previous research. ⢠Project L08 developed the FREEVAL-RL tool. This tool is derived from the FREEVAL model, which implements the freeway modeling methodologies found in the 2010 Highway Capacity Manual (HCM). FREEVAL-RL is intended to test the reliability impacts of projects by dynamically modeling multiple operating scenarios along a facility using a Monte Carloâtype strategy. This tool is more complicated than the previous two tools. The study team calibrated each tool for existing conditions for each facility and then tested multiple scenarios that were developed as part of the CSMP process. Figure ES.4 provides an example of model calibration along the I-210 site using the C11 tool. The study team found that the level of detail in FREEVAL-RL requires significantly more effort than the other SHRP 2 reliability tools. The calibration process is roughly comparable to that of a microsimulation model in terms of time and technical knowledge required. 7
