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AECOM 12 Maintenance of Traffic During Construction/ Construction Staging The City has stated, and our study of the project has reinforced, that the maintenance of traffic during construction is very critical to the success of this project. We have discussed previously in this proposal a potential strategy to minimize the duration of traffic interference, this beingthe roll in structure alternative for the bridge superstructure, since the bridge can be manufactured onsite, while traffic is still in its existing pattern. Only when the new bridge is moved into its final location and during the construction of the majority of the approach work, is there a need to detour the traffic. We have included one possible plan fortraffic handling and construction staging, and this plan corresponds to this proposed construction scheme. Please reference Figure 6. Figure 6 shows utilizing the south side of Santa Ana Boulevard for a detour road, beginning from the [insert detour road photo sent earlier via email adjacent to this paragraph] intersection with Santiago Street on the westerly limit of the project, then turning southerly, before running parallel to Santa Ana Boulevard, finally meeting the existing street alignment and profile near the Fuller Street intersection. This detour road is proposed to be two lanes in each direction. Of course this reduction of the third lane in each direction for the detour road would require the need for further traffic studies to confirm the viability of this configuration in terms of Level of Service (LOS) for both the road and the intersections, and surrounding network of streets.The figure shows the proposed first stage of the construction, during which the majority of the improvements can be completed, with only the south side (eastbound traffic direction) of Santa Ana Boulevard, both at and near the west, and east, end tie-ins to the existing alignment and profile needing to be constructed. The next stage would shift traffic to north side of the roadway, while completing the final work elements. To evaluate the traffic impacts during construction, our approach will look at several alternatives for traffic flow through the project site, and impacts to the surrounding street and freeway network, including: The use of a reversible lane to address peak hour traffic movements. A moveable barrier could be used to provide three westbound lanes in the morning, and three eastbound lanes in the evening. Due to physical constraints at Fuller, consideration might be given to a one-way couplet using Fruit Street for eastbound traffic to Grand Avenue with westbound traffic on Santa Ana Boulevard. This couplet would be join together prior to Santiago Street. Close evaluation of the 1-5 ramps for circulation will also be a key component. With advance notification, traffic utilizing the Grand Avenue exits may instead use 17th Street and 4th Street with alternative routes, further reducing the load on Santa Ana Boulevard during construction. which had an ADT of over 44,000 vehicles per day The RFP mentions the possible need for temporarily locating the railroad operations onto shoofty tracks. This would be necessary for all other strategies for constructing the underpass bridge structure. We have included Figure 7 and this figure shows one possible plan for the alignment of the shoofly tracks, this being easterly of the existing alignment, beginningjust southerly of the 1-5 crossing, turning easterly and then running parallel to the existing tracks until well southerly of the station, and then turning easterly to join the existing track alignments. The RFP also mentions the importance of the shoofly alignments to utilize the station platforms. This alignment achieves that need, with passengers being able to access the westerly track from the existing platform, with a temporary, probably asphalt concrete, platform, which can be constructed for access to the easterly track. An SCRRA Standard Pedestrian Crossing would be required at both ends of the platform to cross the shoofly tracks for access to the easterly track. Metrolink station platform for the rail shoofly tracks Proposal for Protect Study Report Equivalent and Conceptual Engineering Plans for Santa Ana Bcutevard Grade Separation Project