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Grand Avenue Widening Project Environmental Impact Report Section 3.0 Impacts of Alternative 1 Related to Trans ov rtation Potential Traffic Impacts Under Alternative 1 Future Travel Lanes and Traffic Control Devices. Two future scenarios were analyzed for the 2020 horizon year: a build scenario and the No Project Alternative. The 2020 No Project Alternative assumes completion of all ongoing and programmed transportation improvements, without the proposed widening on the project segment of Grand Avenue. The intersection geometry assumed for the 2020 No Project Alternative is the same as the existing intersection geometry for the project segment of Grand Avenue, as shown previously in Figure 3.5-1. The 2020 build scenario assumes the proposed improvements on Grand Avenue are in place by 2020. Under the 2020 build scenario, two alternatives were considered. Both alternatives provide for widening Grand Avenue to six lanes. Alternative 1 provides the widening in a 100 foot wide right-of-way. Alternative 2 provides the widening in a 120 foot wide right-of-way. The additional 20 feet of right-of-way under Alternative 2 provides for an expanded landscaped median and bicycle lanes consistent with the City of Santa Ana Master Plan of Bikeways. The proposed intersection lane configurations under both alternatives are the same. Alternatives 1 and 2 would provide comparable capacity on the project segment of Grand Avenue. Therefore, the LOS analysis for the 2020 build scenario is considered applicable to both alternatives. Figure 3.5-5 shows the assumed intersection geometry under the 2020 build alternatives, reflecting the widened approaches on Grand Avenue. To accommodate the proposed widening, the exclusive right tum lanes on the northbound and southbound approaches of majority of the study intersections would be converted to shared through/right turn lane. In addition to the increase through lanes on Grand Avenue, there are significant improvements to the intersection geometry at First and Seventeenth Streets. At First Street, additional left turn lanes, to provide dual left turn lanes, are provided on the northbound and southbound approaches. Exclusive right tum lanes are provided on the eastbound and northbound approaches. At Seventeenth Street, an exclusive right turn lane is added to the northbound and westbound approaches, and left turn lanes are added to the northbound and southbound approaches, to provide dual left turn lanes on Grand Avenue at this intersection. Future Traffic Volumes. The 2020 traffic volumes used in this study are based on 2020 traffic forecasts prepared by PBQ&D for the Santa Ana Couplet Study, which generated turning volumes at four of the seven study intersections (at Seventeenth Street, I-5 northbound ramps, Santa Ana Boulevard/I-5 high occupancy vehicle (HOV) ramps and First Street). These forecasts were adjusted to ensure consistent traffic volumes between intersections. The traffic forecasts showed an overall traffic growth rate of approximately one percent per year in the City of Santa Ana. This rate was used to develop peak hour traffic forecasts for the remainder of the study intersections (at Fruit Street, Orange County Register driveway and Fourth Street), and daily traffic volumes for midblock locations. F:IPROJ-ENVIGrand eirWew Text- GrandlSection 3 Sp1itlSection 3.5.doc Page 3.5-10