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Technical Procedures 7.3 SUPPLEMENTAL ANALYSIS OF DELAY Because the CCTA Level of Service method applies fixed critical lane volumes uniformly throughout the county, the method may underestimate congestion at locations with poor geometries (older intersections with poor turning radii and small approach widths), or -- overestimate congestion at locations with excellent geometries (newer intersections with ideal conditions) and aggressive drivers. The selected method may not identify locations where severe congestion is limited to a single intersection approach, nor does it reflect significant -- peaking and congestion within the peak hour. To address these shortcomings, the following supplemental analyses may be ' performed jn ;~Clition to usin~ the CCTA's method to identify congested locations: Field measurement of delay on the congested approach or full ' intersection can be collected using the methodology described in Chapter 9, Appendix III of the 1985 Highway Capacity Manual (HCM). The measured delay should be compared with those provided in Table 9-1 of the HCM. The summary of intersection levels of service should be supplemented to reflect the results of the delay analyses when significant variations are found. 7.4 LEVEL OF SERVICE CALCULATION METHOD Signalized intersection levels of service should be calculated using the following nine steps: STEP 1: Lane Geometry Identify the number and type of lanes for each approach. STEP 2: Intersection Volumes Identify by counting (if analysis of existing conditions) or estimating (if analysis _ of future conditions) left-turn, through, and right-turn volumes for each approach for the peak (design) hour volumes in vehicles per hour for each peak hour to be analyzed. In most cases, the analysis will assess both the AM and PM weekday peak hour. For projects with peak -- periods that occur during midday or on weekends, additional time periods should be analyzed.