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PROJECT MEMORANDUM MEETING MINUTES PALMDALE HSR SAP I 1 TO: Mike Behen, City of Palmdale FROM: Roland Genick DATE: 03.29.2019 SUBJECT: City Preferred Vertical HSR Alignment Background Over the past several months the City of Palmdale (CoP) and the California High Speed Rail Authority (CHSRA) have worked collaboratively on a number of potential vertical alignments for a new HSR rail alignment through the CoP. Over the course of that process it has become apparent that two components of the City’s overall Station Area Plan (SAP) and the resulting Palmdale Transit Areas Specific Plan (PTASP) matter most with respect to how the new HSR alignment engages the City. As a result, the CoP has established two main goals that any HSR alignment through the City needs to achieve: - Provide a safe and comfortable, east-west connection across the HSR alignment along Avenue Q and Palmdale Boulevard for all users. This connection needs to be of high Urban Design quality and particularly address needs for bicyclists and pedestrians - Deliver a high-quality passenger experience and overall Urban Design experience for users approaching the station from it’s main public plaza at 5th Street and Avenue Q3 Discussion To achieve the goals established above, the CoP has explored potential alternative vertical alignments to those currently under consideration by CHSRA. The alternatives explored were focused on reducing the amount by which Avenue Q and Palmdale Boulevard need to be lowered to cross underneath the HSR alignment, and on achieveing a more intuitive passenger experience by providing a “below track” passenger concourse at the station. This memorandum transmits two alternative alignments as well as a composite illustration of how the proposed alternative alignment compares to the currently proposed CHSRA alignment. It also transmits two alternate longitudinal sections for Avenue Q and Palmdale Boulevard, illustrating the benefits of their shallower profiles. Lastly it includes pictures of a sample underpass in the the City of Belmont in California that might serve as an inspiration. Specifically, this Memo transmits: 1. A depiction of the currently planned CHSRA alignment for reference (Existing Alignment - CHSRA - 2019.03.29.pdf) 2. A conceptual alternative alignment maximizing east-west connectivity along Avenue Q and Palmdale Boulevard. This alternative pushes the HSR alignment to an elevation that allows Avenue Q and Palmdale Boulevard to stay as close to existing grade as possible while still respecting constraints by CHSRA, UP, and others. (Alternative Alignments - Depressed Plaza 1B _2019.03.29.pdf) 3. A conceptual alternative alignment that balances interests of the CHSRA with inerests of the CoP. This alternative lowers Avenue Q and Palmdale Boulevard as needed but elevates the HSR alignment to levels that make this lowering compatible with the safety and urban design goals established by CoP. (Alternative Alignments - Depressed Plaza 1A _2019.03.29.pdf) ---PAGE BREAK--- MEETING MINUTES PALMDALE HSR - AREA PLAN I 2 4. A composite section that illustrates the differneces between the CoP and CHSRA alignements. This exhibit illustrates that the suggested changes are minor, but are exercised in in a way, and in locations where they truly matter. (Alternative Alignments - Parsons vs CHSRA _2019.03.29.pdf) Specifically, it illustrates: o The difference in vertical alignment at Palmdale Boulevard is minor o Theprofile of the station is virtually identical o The difference in vertical alignment at Avenue Q is negligible 5. Sample photographies of bridges similar to those envisioned for the HSR crossings at Avenue Q and Palmdale Boulevard within the City of Belmont. (Ralston Crossing – City of Belmont) Conclusion To achieve the goals established by the CoP, the vertical profile of a HSR alignment currently contemplated by the CHSRA will need to modified to adequaltely address east-west connectivity, urban design, and quality of user experience. Based on a comparative analysis of the alignments currently under consideration, CoP establishes the following requirements that need to be met for any HSR alignment through the City: - Bottom elevation of any bridge structure across Palmdale Boulevard needs to be a minimum of 7 feet above existing grade. - Bottom elevation of any bridge structure across Avenue Q needs to be a minimum of 10 feet above esxisting grade. - Access to any HSR platform needs to be from a below track passenger concourse. Adhering to the minimum requirements above will allow for the delivery of a HSR station that is consistent with the vision established under the Palmdale HSR SAP.