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Longs, and one trip arriving at home. While this is counted as two trips for Longs, there is no impact to traffic, as the vehicle is already on the roadway. The effect of employing these two concepts reduces the number of vehicle trips resulting from the project. These individuals believe, based on their research of the traffic engineering manuals that created these assumptions, that .using more conservative assumptions would show more traffic at the Santa Rita/Valley intersection than the traffic study shows and that the traffic report therefore understates that traffic. For example, the Home Depot project generates 773 PM Trips. Of these, the number of trips that are internal only was calculated to be 316. This reduces the on street trips to 457 trips. Of these 457 trips, 215 trips were calculated to be already on the adjacent street, leaving a total of 242 new trips that are on the roadway system as a result of the project. Both internal capture and pass by reductions are standard practice in the Transportation Planning industry. The Institute of Transportation Engineers has conducted numerous studies and published "The Trip Generation Handbook" to guide the transportation planning industry in this standard practice. Most of the data within the handbook is from the 1990's and some of the study data is limited in terms of sample size; however, the procedures and numbers have been the standard used in the transportation planning industry for the last 15 years. The residents' greatest concern is the use of a pass-by rate for the project which was based on only 3 studies and that even a small discrepancy in the assumptions would cause an unacceptable amount of traffic on the roadway. Regarding weekday traffic, staff understands the concern of a possible underestimation of the traffic production; however, the City's Traffic Engineer believes that the assumptions in both internal capture and pass-by are reasonable in this case due to the location of the shopping center site on two major arterials which carry significant amounts of commuter traffic, some of which would be expected to stop at the shopping center to visit more than one business on its way to and from work. Although pass-by is a standard trip reduction, the City's Traffic Engineer removed the pass-by assumptions from the trip generation calculation for both the weekday and weekend trip generation to show the impact of the pass-by assumptions. These pass-by trips were added back into the roadway network, and the intersections were analyzed for level of service impacts. The level of service remained the same with the added trips (although the delay slightly increased). Regarding weekend traffic, the supplemental traffic study used the pass by and internal capture rates that have been established for weekday p.m. peak hours. It is likely that there is some level of internal capture and pass-by on the weekend, so it was decided to use these reductions to maintain consistency between the 2006 Dowling report and the supplemental report. However, there are not any published data for weekend internal capture and pass-by that can be used to determine the quantity of these weekend trips; therefore, staff has now eliminated these reductions from the weekend analysis and has re-calculated the levels of service for the critical intersections. Even Page 7 of 14