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2008-07-0517'31 SMITh Eng 5083857891» P314 DEIR Transportation and Circulation Analysis Appears to Be Obsolete Although the DEIR's transportation and circulation analysis superficially appears to be a reasonably detailed one, the traffic impact study on which it is based is somewhat out of date, and the traffic counts on which that traffic impact study is based are even more out of date. The traffic impact study, (DEIR Appendix C) was completed on March 24, 2004. Hence, the study itself is 2.25 years old at the time of this writing. Furthermore, the traffic counts on key state highways relied upon in the DEIR traffic analysis are taken in 2002, so they are about 4 years old as of this time of review of the DEIR. The DEIR traffic counts on local roads were taken in December 2003 and January 2004. The critical issue with older traffic data is that it tends to understate the background traffic conditions and, as a potential consequence, the traffic impacts of the project. This is particularly true of traffic data collected in 2002 and 2003 because traffic in C-1 California generally was still depressed as a result of the economic recession that was felt most heavily in 2002. Traffic counts on Interstate 5 near its interchange with State Route 132 illustrate how radically counts a few years apart can differ. On page 4.4-1 the DEIR reports that "Average Daily Traffic (ADT) on 1-5 is approximately 16,000 vehicles near the SR 132 interchange (Caltrans Traffic Data Unit, 2002)." However, for Year 2005 the same traffic data source (Caltrans Traffic Data Unit) reports that traffic on 1-5 is 20,000 south of SR 132 and 23,800 north of SR 132. Hence, in 2005 the traffic on this key area of the analysis was 25 to 49 percent higher than reported in the DEIR for a date only three years previous. Obviously, if similar levels of difference between current traffic and the older traffic reported in the DEIR are also prevailing on many of the other roads analyzed in the DEIR, the analysis and conclusions of the Transportation and Circulation section of the DEIR would be of no current relevance. In order to establish that the entire basis of the traffic analysis remains relevant, the DEIR must, at a minimum, conduct a sampling of current (2006) traffic counts on local roads in the study area and demonstrate that traffic is minimally changed from the base counts in most locations, or redo the analysis in light of the current traffic data. We also note that although the DEIR, to its credit, accounts for the very significant seasonal variation in project traffic, it fails to account for seasonal variation in background traffic. The project is set in a rural area of generally agricultural character where overall seasonal traffic, like the traffic from gravel operations, tends to peak in the summer months. The Caltrans Traffic Data Unit peaking data for the 2 same segments of 1-5 near SR 132 as discussed above illustrates this point with data from the peak month running 16 to 25 percent higher than the annual average ADT. The traffic counts on local roads used in the DEIR traffic analysis were taken in December and January, months that tend to have below average traffic in rural agricultural areas. Because of the seasonal peaking concerns, the necessary I'KAI I-II' • '1'N \IIS V U N T A ION • Ni ANTI G IS AI L"N I ilI I Lown, Road.Union GtvCA 945$7 A 510,4B9.9477 Cw 310.4899.1',8