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This page intentionally left blank 2 BARTON SPRINGS ROAD BRIDGE OVER BARTON CREEK PROJECT Bridge Concept Engineering Report CIP ID #5873.031 AUSTIN, TEXAS OCTOBER 2023 PREPARED FOR The City of Austin PREPARED BY URS – an AECOM Company Texas P.E. Firm Registration No. F‐3162 13640 Briarwick Drive Suite 200 Austin, TX 78729 Telephone: 512‐454‐4797 Website: aecom.com 3 Date: October 26, 2023 This page intentionally left blank 4 Contents Executive Summary .....................................................................................................................9 1 Project Summary .................................................................................................................11 1.1 1.2 Background ............................................................................................................................... 11 Project Objectives ..................................................................................................................... 11 1.3 Description of the Bridge Project Process ............................................................................. 12 1.4 Project and Report Scope ........................................................................................................ 13 2 Project Area ..........................................................................................................................15 3 Existing Conditions ............................................................................................................16 3.1 3.2 Bridge Cultural/Historical Conditions .................................................................................. 16 Bridge Structural Condition ................................................................................................... 16 3.2.1 3.2.2 Traffic Conditions ............................................................................................................ 17 Preliminary Environmental Conditions ........................................................................ 18 4 Alternative Development and Selection Process .........................................................23 4.1 Initial Assessments (2018‐2019) .............................................................................................. 23 4.1.1 4.1.2 4.1.3 4.1.4 Early Geometric Concepts .............................................................................................. 23 Bridge Rehabilitation Feasibility .................................................................................... 24 Bridge Replacement Concepts ........................................................................................ 24 Design Reviews and Funding Pause ............................................................................. 24 4.2 Bridge Alternative Development (2021‐2022) ...................................................................... 24 4.2.1 4.2.2 4.2.3 4.2.4 4.2.5 Design Charrette .............................................................................................................. 25 City Department Vetting and Alternative Refinement ............................................... 25 Initial Agency Vetting ..................................................................................................... 25 Bridge Alternatives (Comparison of Options) ............................................................. 25 Additional Agency Vetting ............................................................................................. 32 4.3 Public Involvement .................................................................................................................. 32 4.3.1 4.3.2 4.3.3 Open House ...................................................................................................................... 32 Public Comment Summary ............................................................................................. 32 Post Open House Discussions ........................................................................................ 33 5 Proposed Improvements ...................................................................................................34 5.1 5.2 Bridge Cross‐Section ................................................................................................................ 37 Bridge Aesthetic Design .......................................................................................................... 37 5 5.3 5.4 Roadway Design ...................................................................................................................... 38 Park Area Design ..................................................................................................................... 39 5.4.1 5.4.2 5.4.3 5.4.4 Structure/Tree Protection and Mitigation ..................................................................... 39 Zilker Park – Zilker Eagle ............................................................................................... 40 Zilker Park Hike/Bike Trail ............................................................................................. 40 Umlauf Garden Retaining Wall ..................................................................................... 40 5.5 Structural Design ...................................................................................................................... 41 5.6 Utility Design ............................................................................................................................ 42 6 Construction Phases and Methods ..................................................................................44 6.1 6.2 6.3 6.4 Construction Phases ................................................................................................................ 44 Foundation and Substructure Construction ......................................................................... 45 Superstructure Construction .................................................................................................. 46 Construction Sequence/Maintenance of Traffic ................................................................... 46 6.4.1 6.4.2 6.4.3 6.4.4 Phase 1 ............................................................................................................................... 47 Phase 2 ............................................................................................................................... 48 Phase 3 ............................................................................................................................... 49 Final Construction ............................................................................................................ 50 7 Project Cost ..........................................................................................................................51 Appendices Appendix A ‐ Early Studies A‐1 ‐ Section 106 Report – Sept 2016 A‐2 ‐ Bridge Inspection Report – Jan 2017 A‐3 ‐ Traffic Memo – Jan 2018 Appendix B ‐ Bridge Initial Assessments B‐1 ‐ Initial Geometry ‐ Feb 2018 B‐2 ‐ Rehabilitation Feasibility ‐ May 2018 B‐3 ‐ Public Works Management Briefing ‐ July 2018 B‐4 ‐ Preliminary Renderings ‐ Sept 2018 Appendix C ‐ Restart Assessments C‐1 ‐ Project Update – Nov 2021 C‐2 ‐ Draft Interim Bridge Status Memorandum – Feb 2022 6 C‐3 ‐ Design Charrette ‐ March 2022 C‐4 ‐ Rehabilitation vs Replacement Memo – September 2022 C‐5 ‐ MMA Memo City Staff to Council – Nov. 2022 C‐6 – Bridge Alternative Cost Estimates C‐7 – Geotechnical Data Report C‐8 – Proposed Project Construction Cost Appendix D – Agency Discussions D‐1 ‐ Initial TX Historic Commission Meeting – June 2022 D‐2 ‐ Initial US Army Corps of Engineers Meeting – Nov. 2022 D‐3 ‐ Section 106 Evaluation – January 2023 D‐4 ‐ THC Review of Section 106 Evaluation – March 2023 Appendix E – Public Engagement E‐1 ‐ Open House – April 2023 E‐2 ‐ Public Comments – April 2023 E‐3 ‐ Mobility Committee Presentation ‐ May 2023 Tables Table 3‐1. Preliminary Federal/State/City of Austin Permits and Approvals for the Barton Springs Road Bridge Project ................................................................................................. 20 Table 4‐1. Comparison of Bridge Replacement Options ................................................................... 26 Table 4‐2. Comparison of Bridge Rehabilitation/Replacement Concepts ....................................... 27 Table 7‐1. Preliminary Overall Project Cost Estimate ........................................................................ 51 Figures Figure 2‐1. Project Limits ....................................................................................................................... 15 Figure 3‐1. Deterioration of Longitudinal Beam ................................................................................. 17 Figure 3‐2. Preliminary Environmental Constraints Map ................................................................. 19 Figure 5‐1. Bridge Rendering View Looking North ........................................................................... 34 Figure 5‐2. Bridge Rendering View North and East Under Bridge ................................................. 35 Figure 5‐3. Proposed Project and Key Components .......................................................................... 36 Figure 5‐4. Typical Cross‐Section ......................................................................................................... 37 Figure 5‐5. Example of Zilker Park Monuments ................................................................................ 39 7 Figure 5‐6. Bridge Plan and Elevation ................................................................................................... 41 Figure 6‐1. Bridge Phased Construction .............................................................................................. 45 Figure 6‐2. Phase 1 Cross‐Section, Looking East ................................................................................ 47 Figure 6‐3. Phase 2 Cross‐Section, Looking East ................................................................................ 48 Figure 6‐4. Phase 3 Cross‐Section, Looking East ................................................................................ 49 Figure 6‐5. Final Completed Cross Section, Looking East ................................................................ 50 8 Executive Summary This report summarizes the logistical process and technical findings related to the recommendation of the preferred bridge alternative for the new Barton Springs Road Bridge over Barton Creek in Austin, Texas. The purpose and need for this project is centered on safety‐related bridge improvements that address existing conditions such as the age of the existing bridge structure and structural deterioration, as well as insufficient bike/pedestrian paths. The body of this report discusses the inputs and outcomes related to the bridge decision making process. The original project scope included consideration of two bridge rehabilitation options and three options for bridge replacement. The bridge alternatives were developed and then evaluated as a result of the collaboration of key City departmental stakeholders through a series of meetings. The outcome of this process was the recommended Bridge Replacement Option 3 ‐ a replacement bridge consisting of a three‐span concrete girder structure supported by two lines of custom “Y” Piers which flank the center channel of Barton Creek. Figures E‐1 and E‐2 are renderings of the recommended bridge option from different vantage points. Figure ES‐1. Bridge Rendering View Looking North 9 Figure ES‐2. Bridge Rendering View North and East Under Bridge As part of the project, a combination in‐person and virtual public open house was held in April 2023 and solicited public feedback on the proposed design alternatives. Public sentiment was mixed and varied from making no changes, to voicing favor for both rehabilitation and replacement alternatives. The recommended design limits in‐water obstructions for users while maximizing the views through and under the bridge. The bridge piers are oriented transversely to the structure which helps to create the greatest sense of openness when viewed from Barton Creek below. The western abutment for the bridge has been relocated to the west. This is important on the park side of the bridge because it increases the amount of usable space underneath the bridge and along the creek, accommodating new multi‐use paths and the Zilker Eagle train. The pedestrian and bicycle accommodations on the deck of the bridge are significantly enhanced from the existing condition. The new bridge will have very wide sidewalks and mixed‐use paths on either side that can accommodate the significant crowds during key park events. The project will reconnect bike and pedestrian facilities to connect to existing Zilker Park facilities. The Barton Springs Rd./Azie Morton Rd. intersection will be revised to accommodate the additional Azie Morton right‐turn lane, as well as the revised roadway and bike lane layouts. The existing Umlauf Garden retaining wall at Azie Morton Rd will be replaced, addressing the hillside instability adjacent to Umlauf Gardens. Utilities in the immediate vicinity of the bridge and intersection will be either replaced, relocated, or potentially upsized/improved during the construction. Preliminary project cost estimates were prepared. The overall preliminary project cost estimate is $36,660,000. 10 Project Summary Background 1 1.1 The City of Austin is evaluating design for rehabilitation or replacement of the Barton Springs Road Bridge over Barton Creek. The location of the bridge, at the entrance to Zilker Park, is a focal point of key community events such as the Austin City Limits Music Festival, South by Southwest Conference and Music Festival (SXSW), Barton Springs, Trail of Lights, and Blues on the Green. Barton Creek and nearby Barton Springs are key community locations and focal points of environmental and social sensitivity within the context of many events. Barton Springs Rd. and the associated bridge is also a key connection for vehicular, bike, and pedestrian access linking Mopac to downtown and the South Lamar/Congress corridors, as well as providing the primary northern entrance to the Zilker and Barton Hills neighborhoods via Azie Morton Rd., located immediately east of the bridge. The three‐span open spandrel concrete arch bridge was originally built in 1925 and was expanded to the north in 1946. The current bridge is 212’ long and 58’‐8” wide. The age of the structure has warranted progressively more detailed inspection and condition assessments over time. In addition, the bridge geometry is functionally obsolete with respect to bikes and pedestrians, and the roadway west of Azie Morton is un‐aligned with the roadway east of Azie Morton. The City’s preliminary bridge deck concept approximately doubles the width of the bridge deck to accommodate wider sidewalks on either side of the bridge, two bicycle lanes, four travel lanes, and a median to match the cross section of Barton Springs Road established by a previous reconstruction of that roadway east of Azie Morton. The bridge is currently a bottleneck, with congestion for all modes of travel at the Barton Springs Road/Azie Morton intersection. The proximity of the bridge and Azie Morton intersection (including structural cantilevered sidewalk) specifies the two features are integral to one another. For that reason, in addition to the evaluation of the bridge structure, the City is interested in understanding the potential for reducing congestion at this intersection and entrance to Zilker Park via assessment of potential improvements to the combination of roadway, bridge, and intersection. Reducing congestion will provide future benefits to the local neighborhoods, commuters (all travel modes), local businesses, as well as Zilker Park users and event attendees. Project Objectives 1.2 The purpose and need for this project is centered on safety‐related bridge improvements that address the following items: 11 Age of structure/structural deterioration; Insufficient bike/pedestrian paths (functionally obsolete); Bridge roadway lanes not aligned with lanes east of Azie Morton; Hillside instability (rock fall) and obsolete retaining wall on Azie Morton east side of intersection; Elevated/overhanging sidewalk integral to intersection – past movement/cracking; and Bridge/intersection congestion. In addition to the project objectives, the bridge alternatives needed to provide the following performance features: Four (4) traffic lanes, per the historic bridge layout. Roadway geometry and alignment improvements. Intersection improvements to decrease traffic delays. Two (2) new, dedicated bike lanes. Two (2) pedestrian sidewalks, with significant width increases beyond the existing. Varying bridge configurations that cross Barton Creek. Provisions for maintaining and/or improving the various existing modes of travel from the existing sidewalks, pathways, and hike/bike trails adjacent to and under the bridge. A 75‐year design life. Context‐sensitive aesthetic design solutions sympathetic to stakeholder guidance and input. Description of the Bridge Project Process 1.3 The overall process for the Barton Springs Rd. Bridge project will follow the general phases listed below: Preliminary Selection and Concept Engineering. This phase assesses the feasibility of bridge rehabilitation or replacement. The evaluations will consist of assessments such as bridge structural engineering, architectural, roadway, and bike/ped mobility, as well as environmental feasibility. These options will be developed and analyzed, and the evaluations vetted by City of Austin stakeholder departments and management. Public involvement will be conducted. The result of the Preliminary Selection phase will be a vetted/recommended bridge design option; this phase will be documented in this Bridge Concept Engineering Report (BCER). The approved/confirmed design option will then proceed to the design phase. 12 Preliminary (30%) Design. This phase consists of the 30% Design and the Preliminary Engineering Report. The primary outcomes of this phase include obtaining detailed design information from onsite topographic and bathymetric surveying, engineering field investigations, and environmental field investigations. This detailed information will allow for preliminary engineering of the total project, including bridge, roadway, retaining walls, utilities, and remaining wall work within the identified limits of construction. It will also allow for early coordination with federal, state, and local permitting agencies to vet the design and determine the available strategies for obtaining permits/approvals of the design to support later construction efforts. Final Design and Permitting. Includes detailed design for all disciplines, and obtaining permits and approvals from all federal, state, and City agencies and departments. Within this phase, detailed design calculations, drawings, specifications (instructions to contractors on materials, testing, and performance requirements), and estimated construction costs are developed and submitted to the City for review and vetting. The design is submitted and vetted in the 60%, 90%, and 100 phases. During each of these phases various design disciplines develop the details of their respective designs, as well as coordinate between designs for the overall project objectives. Some of the design disciplines include bridge/structural; retaining walls; roadway/traffic engineering; signalization/signage/pavement marking; drainage and water quality; environmental and landscape disciplines for tree and overall environmental protection; and utility design for relocation or replacement of existing utilities in conflict with construction. All the work will undergo permit applications and related discussions with agencies for the various permits and approvals that are anticipated and that are discussed later in this report. Bidding and Construction. This phase includes soliciting and obtaining bids from construction contractors; reviewing and recommending the bids for approval; and City approval of the bids for contracting. This phase will then include City contracting with the construction contractor; and then managing the construction process to completion. Project and Report Scope 1.4 The original project scope for the concept phase included consideration of two potential bridge rehabilitation options and three options for bridge replacement. A general description of these options is: Rehabilitation Option 1: This option has a focus to rehabilitate but preserve the existing structure. This option includes consideration of a retrofit bridge railing system to upgrade the substandard existing railings. This option also includes consideration and 13 feasibility of a complementary structure or other means to adequately address additional capacity desired for bike and pedestrian traffic on both sides of the bridge. Rehabilitation Option 2: This option focuses on rehabilitating the existing structure and enhancing the deck by widening it to incorporate wider sidewalks and a bike lane on both sides. The deck would either be placed on the existing substructure or a widened, expanded substructure, as necessary. Replacement Options: Three options were originally set aside to address complete reconstruction of the bridge, to be designed to modern structural codes and to include a wider bridge deck to allow for realigning the Barton Springs Road intersection for improved safety, bike lanes on both sides, and wider ADA compliant sidewalks. As the project developed, the following three replacement options were identified: - Replacement Option 1 – Single Span Concrete Arch, generally spanning the entire creek. - Replacement Option 2 – Two‐Span structure with piers located in centerline of Barton Creek. - Replacement Option 3 – Three‐Span structure with piers located in the general vicinity of the current/existing bridge piers. This report summarizes the development and evaluation of the above bridge alternatives. It includes the design work and the input and outcomes of the decision‐making processes resulting in the conceptual development of a recommended bridge option. 14 Project Area 2 The Barton Springs Road bridge project is located where Barton Springs Road crosses over Barton Creek. The limits of the project are shown in Figure 2‐1, and include the bridge over Barton Creek, the transitional roadway from the bridge west into Zilker Park at Lou Neff Road, the Azie Morton/Barton Springs intersection, and the transitional roadway and sidewalks along Azie Morton immediately south of the intersection. Figure 2‐1. Project Limits 15 Existing Conditions Bridge Cultural/Historical Conditions 3 3.1 The original Barton Springs Road bridge was built in 1925 and widened to its current configuration in 1945. The bridge is located adjacent to Zilker Park, which is listed in the National Register of Historic Places (NRHP); the bridge is considered a contributing resource to the Park. The Barton Springs Archeological and Historical District (formed in 1985) is also located within the Zilker Historic District and the downstream boundary of this district is in close proximity to the bridge. It is understood that all planning and design work will also include coordination and discussions with key cultural/historic preservation stakeholders such as the Texas Historic Commission (THC). Appendix A‐1 includes the Section 106 Technical Guidance Memo, which was provided early in the project, to identify the level of effort to conduct coordination with agencies. Section 106 refers to Section 106 of the National Historic Preservation Act of 1966 (NHPA), providing guidance to agencies to consider the effects on projects on historic properties. Bridge Structural Condition 3.2 A detailed bridge inspection was performed in 2016, including an arms‐length inspection of most structural members, via snooper truck. The Bridge Inspection and Condition Assessment Report for Barton Springs Road Bridge (included in Appendix A‐2) was submitted in January 2017. The condition assessment report indicated that the overall bridge was in fair condition; however, the deck (with integral longitudinal joint), floor beams, and spandrel columns had exhibited the most degradation, although all structural components had exhibited degradation. 16 Figure 3‐1. Deterioration of Longitudinal Beam As a result, any rehabilitation desiring increased service life would need to remove the deck, floor beams, and spandrel columns, essentially stripping the structure down to the arch ribs as a starting point. As indicated in the report, these results, by definition, removed the original Rehabilitation Option 1 (as described in Section 1.2) as a feasible alternative, since the intent of that option was a ʺlow‐impactʺ, “preserve‐structure” rehabilitation option from visual, construction, and cost standpoints. Based on the above, the team focused on Rehabilitation Option 2 and on potential bridge replacement options moving forward. Traffic Conditions 3.2.1 A Traffic study and memo was submitted in January 2018 (Appendix A‐3). Traffic counts and modeling were conducted to analyze existing levels of service and to perform an intersection analysis to reduce congestion and delays in the intersection. This was done to help guide decisions on how to treat the Azie Morton/Barton Springs intersection; due to the proximity of the intersection to the bridge, the intersection and bridge concepts needed to be treated together. 17 The traffic study recommended adding a right turn lane from Barton Springs Rd. to Azie Morton and another right turn lane from Azie Morton to Barton Springs Rd. This was vetted with ATD in 2017‐18 and incorporated into the conceptual plans at that time. Preliminary Environmental Conditions 3.2.2 A conceptual boundary of the limits of the project area impacts were developed and used to identify proximate environmental resources and considerations. At this stage there was no distinction made between bridge rehabilitation and replacement alternatives since their limits of construction operations are so similar. Figure 3‐2 was developed based on the preliminary findings; this figure shows some of the anticipated environmental constraints in and around the project area. This map or similar maps will be developed and updated as future, more detailed investigations are conducted. Table 3‐1 provides a preliminary list of environmental permits and approvals that have been identified as potentially applicable, and which will be further vetted in the design phase of the project. Further investigations and data collection may show that some of these potential requirements are not applicable. 18 Figure 3‐2. Preliminary Environmental Constraints Map 19 Alternative Development and Selection Process 4 As indicated in Section 3, several studies were performed (circa 2016‐2018) to identify existing conditions of the bridge structure as well as the existing traffic and environmental/permitting issues. These were precursor studies to allow for further alternative development and evaluation. Sections 4.1 to 4.3 present summaries of these additional evaluations, studies, and meetings which comprised the process used to develop, evaluate, and recommend the preferred bridge alternative. City Departmental stakeholders assisted in the evaluation of designs and provided guidance from a broad range of perspectives. The City’s participant team members included: City of Austin – Transportation and Public Works (TPW) City of Austin – Parks and Recreation Department (PARD) City of Austin – Austin Water (AW) City of Austin – Austin Energy (AE) City of Austin – Watershed Protection Department (WPD) City of Austin – Historic Preservation Office (HPO) Other stakeholders have had input into the design, either directly with team member meetings and discussions, or from participation in public engagement efforts. Some of these additional stakeholders include: U.S. Army Corps of Engineers (USACE) U.S. Fish and Wildlife Service (USFWS) Texas Historic Commission (THC) Texas Commission on Environmental Quality (TCEQ) Save our Springs Alliance (SOS) City of Austin citizens through in‐person and virtual Open House Initial Assessments (2018‐2019) Early Geometric Concepts 4.1 4.1.1 Appendix B‐1 includes preliminary plan views of the bridge and roadway geometries for Rehabilitation and Replacement bridge options. These were developed in February 2018 and discussed with City TPW at the time. 23 4.1.2 Bridge Rehabilitation Feasibility In 2018, structural modeling was done to determine the feasibility of the Rehabilitation Option 2. In May 2018, preliminary results of the rehabilitation structural modeling were discussed with TPW. Appendix B‐2 provides the presentation slides from that meeting. The outcome was that a feasible rehabilitation solution was available. 4.1.3 Bridge Replacement Concepts In Summer of 2018 early bridge replacement option concepts were developed vetted with TPW staff. This included preliminary development of a Maintenance of Traffic plan, which was developed to ensure that four lanes of traffic were able to be maintained during construction. In July 2018, a briefing was provided to TPW to update on the status; Appendix B‐3 includes the slides from the briefing, with topics including project overview; bridge inspection; rehabilitation feasibility; maintenance of traffic during construction, and conceptual sketches for bridge replacement. In September 2018 bridge replacement option renderings were developed and discussed with TPW staff. Appendix B‐4 includes a copy of the renderings developed. 4.1.4 Design Reviews and Funding Pause A draft of an Interim Bridge Status Memorandum was developed in late 2018 and vetted with the City in January 2019. During the first months of 2019, various tasks were discussed and explored for moving the project forward, including: Potential for CAMPO funding (in May 2019 it was determined that TxDOT had utilized those funds); Potential for federal BUILD Grant funding; and Potential for early public input and strategy and cost for public involvement. In July 2019, the project was paused due to a lack of further funding, to complete the remainder of the Concept Engineering and Public Involvement. 4.2 Bridge Alternative Development (2021‐2022) The design team performed additional structural modeling in late 2021 to provide a similar level of structural vetting for the replacement options, as had been performed for the rehabilitation option in 2019. The modeling and associated renderings were discussed with Public Works management team in November 2021. Appendix C‐1 includes a copy of the slides from this meeting. 24 The draft Interim Bridge Status Memorandum (referenced in Section 4.1.4) was finished in draft form in February 2022, and was distributed to the City’s stakeholder departments/groups in advance of the Design Charrette. Appendix C‐2 includes a copy of this memorandum. 4.2.1 Design Charrette A Design Charrette was held March 2022, and was attended by multiple City stakeholder departments. The meeting oriented the group and reviewed the background and history, and the process for selecting an alternative for the bridge. The design team recommended a bridge replacement for the general project direction. Appendix C‐3 includes a copy of the agenda and the slide deck from that meeting. The meeting provided general input from various departments, and it was understood that additional input would be provided as the slides were studied more in depth. One outcome was the decision to contact the Texas Historical Commission (THC) for general orientation and to obtain their initial input into general project direction. 4.2.2 City Department Vetting and Alternative Refinement Various additional meetings were held with City Departments in Spring and Summer 2022. The primary outcome of these meetings was a revision to the geometry for both the rehab and replacement options. ATD comments resulted in the following primary alternative revisions: The right‐turn lane from Barton Springs to Azie Morton was removed; Road lanes were narrowed; and Bike lanes and pedestrian paths were widened. Initial Agency Vetting 4.2.3 In June 2022, the design team met with THC and presented the project, after incorporating the general revisions to alternatives from departmental input. Appendix D‐1 includes the slide deck from this meeting. The outcome from this meeting was that THC requested that the U.S. Army Corps of Engineers (USACE) be contacted for consultation (as lead federal agency). The THC also requested some additional documentation in memorandum form for their review, prior to public outreach, to review the feasibility of both rehab and replacement options. 4.2.4 Bridge Alternatives (Comparison of Options) As a result of the input from City stakeholders and THC, the rehab and replacement alternatives underwent additional review and comparisons. The Rehab vs. Replacement Memorandum was developed (August 2022 draft and finalized September 2022) to provide documentation and a matrix of the comparisons between all alternatives, and highlighting 25 report was developed in draft in October 2022, and is included in Appendix C‐7, and provides additional information on subsurface conditions in and around the bridge. 4.2.5 Additional Agency Vetting The Rehab vs Replacement Memorandum was submitted to both the THC and USACE in November 2022. A meeting with USACE was held in November 2022 to discuss the project and initiate consultation. Meeting notes from this call are included in Appendix D‐2. In addition to the memorandum, a Section 106 Evaluation was developed to provide the THC more information on the implications and effects of both alternatives on historic properties. The memorandum was developed in draft form in December 2022 and submitted to THC in January 2023. It is included in Appendix D‐3. The THC responded to the memorandum in an email in March 2023, agreeing with the Section 106 Evaluation, and indicating that the project could proceed with either rehab or replacement options and that both options had similar cultural/archeological impacts. The email from THC is included in Appendix D‐4. Public Involvement 4.3 The design team began preparations for the city‐wide open house in late summer 2022. The targeted time frame for the Open House was November 2022. During the course of coordination with other departments, it was requested that the bridge Open House be delayed allowing for the progress of other studies and public outreach in progress at the time. The bridge open house was postponed to Spring 2023. 4.3.1 Open House The Open House was held April 2023 (originally scheduled event in March was cancelled by a severe storm the day of). The open house was a combined in‐person open house, and virtual open house. The virtual session began in early March and continued through roughly the middle of April 2023. Appendix E‐1 contains both a copy of the boards that were present in the in‐person open house, as well as the slide deck that was provided for the virtual open house. Public Comment Summary 4.3.2 Public comments were gathered in two ways: on paper during the in‐person meeting and online as part of the virtual public meeting. Overall there were 1,677 views of the public meeting; 189 participated in the online survey. Overall sentiment varied with the major sentiment categories of either favoring rehabilitation, favoring replacement, or not wanting any changes. A public meeting summary was developed and is included in Appendix E‐2. 32 Post Open House Discussions 4.3.3 Various additional discussions have taken place with City management in the time frame after the public engagement process. Public Works management provided a briefing to the City’s Mobility Committee in May 2023. Appendix E‐3 includes the slide deck from the presentation. 33 Proposed Improvements 5 The recommended Bridge Replacement Option 3 is a three‐span concrete girder structure supported by two lines of custom “Y” Piers which flank the center channel of Barton Creek. Figures 5‐1 and 5‐2 are renderings of the recommended bridge type from different vantage points. Figure 5‐1. Bridge Rendering View Looking North 34 Figure 5‐2. Bridge Rendering View North and East Under Bridge The following sections provide additional information on the recommended alternative. Figure 5‐3 below includes an overall view of the proposed project with the proposed bridge and additional key ancillary project components. 35 Figure 5‐3. Proposed Project and Key Components 36 Bridge Cross‐Section 5.1 The proposed cross‐section for the Barton Springs Road Bridge over Barton Creek was developed after consultation with City’s transportation engineers and bike/pedestrian coordinators, and consists of: 1. One (1) – 5‐ft. center median; 2. Two (2) – 10‐ft. inside lanes; 3. Two (2) – 10‐ft. outside lanes with 1.5‐ft. striped shoulder; 4. Two (2) – Traffic barriers assumed to be nominal 2‐ft. wide; 5. Two (2) – 10‐ft. bike lanes; 6. Two (2) – Interior pedestrian barriers that separate bikes and pedestrians, assumed 2‐ft. nominal width; 7. A 13.66‐ft. multi‐use path on the North side of the bridge and a 17.66‐ft. multi‐use path on the south side of the bridge; and 8. Two (2) – Exterior pedestrian barriers, assumed 1‐ft. nominal width. The proposed bridge typical sections are shown in Figure 2.1. The roadway utilizes a standard crown section with 2 percent cross slopes to facilitate drainage. The deck will drain via the gutter line to inlets located at either end of the bridge. The overall deck width is derived from the needs of Maintenance of Traffic (described in more detail in Section 6.3). That is to say that the overall deck width is needed to ensure that four lanes of traffic stay operational during construction. Figure 5‐4. Typical Cross‐Section Bridge Aesthetic Design 5.2 The design for the recommended bridge is a three‐span concrete girder structure supported by two lines of custom “Y” Piers which flank the center channel of Barton Creek. This design limits in‐water obstructions for users while maximizing the views through and under the bridge. The bridge piers are oriented transversely to the structure which helps to create the greatest sense of openness when viewed from the river below. In addition, a large number of users will be 37 beneath the bridge and on the trail system. These users will experience views of the bridge from an oblique angle. The orientation of the piers provides the greatest amount of visual interest for users at these different vantage points. The forms of the piers utilize curved and arching shapes which pay homage to the existing bridge. The western abutment for the bridge has been pushed back slightly. This is especially important on the park side of the bridge because it increases the amount of usable space underneath the bridge and along the creek, accommodating new multi‐use paths and the Zilker Eagle train. The pedestrian and bicycle accommodations on the deck of the bridge are significantly enhanced from the existing condition. The new bridge will have very wide sidewalks and mixed‐use paths on either side that can accommodate seating areas with integral planters, custom railing systems, and adequate lighting. Barriers separating the travel lanes from the shared use path along with a raised and planted center median will help to create a more pedestrian and urban experience. Roadway Design 5.3 Roadway design for the bridge approach was derived from allowable geometry around physical constraints in the environment. There are two significant constraints on either side of the Barton Springs Bridge. On the East side is the intersection with Azie Morton. Barton Springs Road, westbound, has a left turn lane for traffic turnings south onto Azie Morton. The same turn lane must be tapered away before the bridge begins. To do this, the turn lane was centered on the proposed alignment. This allowed both the East and West approaching lane to share the taper and decrease the lane shift for each direction of traffic across the intersection. The second significant constraint on the West side of the bridge is the two Zilker Park Monuments. 38 Figure 5‐5. Example of Zilker Park Monuments These monuments are historical in nature and must be avoided in the development of this project. One monument is on the North side of the road and there is another on the South side of the road. The geometry used to preserve these monuments was chosen to facilitate the desires of this project and meet the cityʹs design criteria. Park Area Design 5.4 A review of opportunities for park/pedestrian improvements were developed in the Interim Bridge Status memo (see Appendix C‐2 for more detail). Structure/Tree Protection and Mitigation 5.4.1 Key historic structures such as the existing park monuments and the pecan grove picnic area will be protected from disturbance during the work; these important facilities are part of the historical character of the park. Heritage trees that have the potential to be in conflict with the bridge construction have been assessed; these trees can be moved/re‐located to mitigate 39 potential damage or alternatively can be stabilized and protected depending upon the degree of conflict. These aspects of the work will be coordinated with City stakeholders throughout future design efforts. Zilker Park – Zilker Eagle 5.4.2 The preliminary plan includes the provision of additional space for the Zilker Eagle track. The plan will be vetted and coordinated with the Parks Department and the overall planning needs for Zilker Park. After the project construction, new tracks will need to be placed in/around the bridge abutment and reconnected with the existing track at some determined distance from the bridge. The proposed design provides a shift of the abutment to the west and provides an opportunity for more horizontal and vertical space for the train and riders, as well as pedestrians. Zilker Park Hike/Bike Trail 5.4.3 The hike/bike trail immediately under the proposed bridge will likely be in conflict with the bridge construction; as a result, it will likely require replacement in the vicinity of the bridge. In addition to potential construction conflict, the existing east‐side trail underneath the bridge has also exhibited erosion/undercutting from Barton Creek. As a result, the proposed project will also likely include bank stabilization in these areas, in coordination with ongoing efforts from the WPD. The existing west‐side trail underneath the bridge includes a pedestrian bridge that is located to avoid the existing arches. For the recommended design, the pedestrian path will be able to be re‐located onto the bank adjacent to a re‐located west abutment, with the additional space made available on this side. This will require a retaining wall and additional bank stabilization at the toe of the wall, as is likely on the east bank. 5.4.4 Umlauf Garden Retaining Wall The Umlauf Sculpture Garden and Museum is part of the City’s Parks and Recreation Department. The existing Umlauf Garden retaining wall and hillside on the east side of Azie Morton at the southeast corner of the Barton Springs Rd. intersection has exhibited instability in the recent past. This hillside is directly below the Umlauf home and workshop. The enhancement of the right‐turn lane at Azie Morton will be combined with the construction of a replacement retaining wall to stabilize this hillside. Construction of these elements early in the project’s construction sequence will also allow for Azie Morton roadway to shift to the east, maintaining traffic flow for the neighborhood while also providing additional construction space near the bridge. 40 Utility Design 5.6 Existing utilities on the bridge consist of the following: 6” coated steel gas line; and 6” cast iron water line. In addition to the utilities connected to the bridge, there are various overhead utilities for energy and communications spanning Barton Creek. Additionally, there are underground and overhead lines adjacent to Azie Morton Rd. The gas line and water line on the bridge will be replaced. In preliminary discussions with Austin Water (AW), the 6” line will be replaced by an upsized 12” line. Preliminary discussions with Texas Gas indicated that they would self‐perform a gas line replacement and bore under the creek. Additional discussions and coordination with Texas Gas will be conducted during the design phase. The roadway and bridge work will require existing electric lines to be relocated. Austin Energy (AE) will design the relocation of their own poles and overhead transmission and/or 42 distribution lines. The design team will coordinate same with project construction phasing. It is also typical for Austin Energy to coordinate the use of their overhead power poles for communication line purposes. This will be coordinated and confirmed during the design phase as well. 43 6 6.1 Construction Phases and Methods Construction Phases 44 6.2 Foundation and Substructure Construction 45 6.3 Superstructure Construction 6.4 Construction Sequence/Maintenance of Traffic Extensive effort was expended to thoroughly consider Maintenance of Traffic (MOT) within the preliminary design of this project. MOT on this key arterial street will be critical during the construction of this bridge project. A preliminary construction sequence and phasing plan was developed with the intent of maintaining all four lanes of traffic operational during construction. The sequencing and lane management are important to avoid overloading existing structures and sequentially accommodating the new foundations. 46 Phase 1 6.4.1 Phase 1 is described in Figure 6‐2, looking to the East. Figure 6‐2. Phase 1 Cross‐Section, Looking East Step 1. Maintain traffic along Barton Springs Road generally in existing locations with appropriate protections (concrete barriers and advanced warning devices) installed to inform and protect traveling public and to protect construction workers, materials, and equipment. The initial bridge work consists of constructing new bridge foundations, superstructure, and decking north and south of the existing bridge. The existing traffic would continue as normal while these new bridge elements are constructed offline. Construct north and south portions of Barton Springs Road bridge/approach pavement with appropriate permanent and temporary barriers as well as retaining wall and pavement cantilevered sidewalk along east side of Azie Morton Road. Step 2. The west and east ends of both new bridge segments will be connected to the existing roadway and sidewalk network. This will require some temporary traffic routing. 47 6.4.2 Phase 2 Phase 2 is described in Figure 6‐3. Figure 6‐3. Phase 2 Cross‐Section, Looking East Update MOT signs, structures, and devices to facilitate Phase 2 work. Split west‐bound (WB) traffic along Barton Springs Road. One lane will be routed onto the new bridge constructed during Phase 1, and the other lane will be routed down the existing outside lane of WB traffic. Split east‐bound (EB) traffic along Barton Springs Road. One lane will be diverted to what was the inside lane of WB traffic, and the other will be routed onto the new bridge constructed in Phase 1. The EB lane will be able to turn right onto Azie Morton or straight on Barton Springs Road. Shift EB pedestrian traffic from the existing bridge to the new bridge constructed in Phase 1. Demolish southern half of bridge. This is the existing EB (and circa 1925) bridge elements. Construct southern interior portion of proposed Barton Springs Road bridge and approach pavement. Splice together girder and decking with previous decking from Phase 1. 48 6.4.3 Phase 3 Phase 3 is described in Figure 6‐4. Figure 6‐4. Phase 3 Cross‐Section, Looking East Update MOT signs, structures, and devices to facilitate Phase 3 work. Shift and split WB traffic along Barton Springs Road. One lane will continue on the bridge built in Phase 1. The other lane will be shifted south onto the new bridge built in Phase 2. Split EB traffic along Barton Springs Road. One lane will remain on the bridge built in Phase 1. The other lane will be routed onto the bridge built in Phase 2. Maintain pedestrian traffic as it was in Phase 2. Demolish northern half of bridge. This is the existing WB (and circa 1945) bridge elements. Construct northern interior portion of proposed Barton Springs Road bridge and approach pavement. 49 6.4.4 Final Construction Final work is described in Figure 6‐5. Figure 6‐5. Final Completed Cross Section, Looking East Update MOT signs, structures, and devices to facilitate final tasks for bridge completion. Remove temporary features no longer needed. Route all Barton Springs Road traffic onto permanent approach pavement and bridge completed in previous phases – shift lanes toward median to extent necessary to construct barriers between roadway and pedestrian areas. Construct final bike/pedestrian barriers. Shift vehicle and pedestrian traffic into final proposed locations after miscellaneous elements are completed. Install and complete utilities and finishing works. Remove all remaining temporary features and perform final site cleanup for project acceptance by the City. 50 Project Cost 7 A conceptual project cost estimate has been developed for the Barton Springs Rd. Bridge project. Quantities were estimated from conceptual layouts presented above. As discussed in Section 4.2.4 preliminary construction costs for the bridge and overall project were developed. Unit costs were based on a review of City of Austin and Texas Department of Transportation average low bid unit prices along with past experience of comparable projects. A 25% contingency was applied to construction costs due to the preliminary/conceptual level of the design at this juncture. Construction costs are provided in 2023 dollars and are subject to change. The total construction cost for the proposed Bridge is $27,600,000. The detailed total construction cost is provided in Appendix C‐8. The total construction cost was summarized, and design and management costs added, to provide an overall estimated project cost, provided in Table 7.1. Table 7‐1. Preliminary Overall Project Cost Estimate 51 Appendices Appendix A - Early Studies A-1 - Section 106 Report – Sept 2016 BARTON SPRINGS BRIDGE AUSTIN, TEXAS SECTION 106 TECHNICAL GUIDANCE MEMO September 16, 2016 Physical and Locational Description: The Barton Springs Bridge is a concrete, open spandrel deck arch bridge located in the Zilker Metropolitan Park in Austin, Texas. The bridge has three open spans which sit on concrete piers. The abutments extend into the ground. The decking and sidewalk terminate at the end of the abutments. The total length of the bridge is 212.0 feet and the length of the largest span is 70.0 feet. The deck width is 48.0 feet. The bridge has open spindle handrails positioned between concrete posts. The Barton Springs Bridge is located within the Zilker Metropolitan Park, a City of Austin recreational area. The Park comprises over 350 acres and has many recreational activities. A hike and bike trail as well as the Zilker Zephry miniature train which runs under the bridge adjacent to the north abutment of the bridge. The Park was listed in the National Register of Historic Places (NRHP) on 1997, and the Barton Springs Bridge, which is a contributing resource to the NRHP, is located within the Park. The Barton Springs Archeological and Historical District are also located within the Zilker NRHP and the boundary is immediately adjacent to the Barton Springs Road Bridge (Exhibit 1 Map of Zilker Park and the NRHP boundary). History of the Bridge: Bridge was constructed in 1926 by A.A. Mundy of Austin (Contractor) and The Terrell Bartlett Engineers Inc. of San Antonio, Texas (Exhibit 2). The bridge was widened in 1946 to accommodate more traffic (Exhibit 3). Proposed Modifications to the Bridge: Prior to beginning the design for the Barton Springs Bridge, a Bridge Conceptual Engineering Report (BCER) will be prepared. The report, prepared by the Bridge Design Team will address three general design options as defined below Option 1: Restore Load Capacity and Preserve Existing Structure The first option will be to rehabilitate and preserve the existing structure in accordance with the Secretary of Interiors Standards for Rehabilitation. This option may include among others, consideration of a retrofit, classic-style, bridge railing system to upgrade the substandard existing railings. This option may also include consideration and feasibility of a complimentary structure 1 | P a g e or other means to adequately address additional capacity desired for bike and pedestrian traffic on both sides of the bridge. The four goals of Option 1 include: a) Improve deck and structural superstructure (and substructure if necessary) to accommodate traffic loads; b) No expansion of sidewalks or deck; c) Replace railings; and, d) The design of potential companion bridge(s) for bike/pedestrian use. The replacement of the classic-style railing and barrier system will need to meet current safety standards. The design of the new barriers should preserve the historical character of the existing railings as closely as possible. This can be accomplished by developing a custom design which would require crash-testing of the system. This can be expensive and time consuming and may not be feasible for a project of this limited scale. Another approach includes the development of railings and barriers that are based on existing, crash-tested designs which can be modified slightly to preserve the character of the bridge. This approach has been used successfully on other historic bridge restorations include the First Street Viaduct in Los Angeles, CA and the Venetian Causeway in Miami, FL. A companion bridge(s) may be designed to add additional pedestrian and bicycle capacity. This bridge should complement the existing bridge, while utilizing the most current design techniques and materials to create a new bridge that is clearly of its time Section 106 Requirements and Review for Option 1: It is critical that early and continued coordination and discussion be held with the THC in order to keep the project moving in a timely basis. Prior to the creation of any rehabilitation and/or retrofit designs for the Bridge, it is recommended that the City initiate coordination between the Texas Historic Commission (THC) (State Historic Preservation Office - SHPO). Early coordination would consist of: Meeting with the THC to discuss City’s purpose and need of the project; Discussion of rehabilitation and retrofit designs and options for the bridge; Discussion of what the THC perceives are the significant elements of the bridge; Discussion of any perceived impacts to the NRHP Zilker Park; Discussion of any impacts to the Barton Springs Bridge as a result of constructing a companion bridge immediately adjacent to the current bridge; and, Discussion of public involvement since the bridge is within the NRHP Listed Zilker Park. It is recommended that the attendees for this meeting include City officials overseeing the Bridge project, bridge engineers, bridge architect, and the architectural historian. This meeting will provide the bridge engineers with guidance as to what the THC would prefer in terms of design and materials. While the Barton Springs Bridge is currently not listed on the NRHP, it is an element within the NRHP listed Zilker Park. Preliminary review of the Bridge and its history would indicate that the 2 | P a g e bridge would be individually eligible for listing. During the discussion with the THC, it will be asked whether the THC would like to see a formal Section 106 recording of historic properties report prepared by an architectural historian. At the meeting, the THC will be asked if they (THC) would make the NRHP determination based on their own recommendations, thereby avoiding the process of preparing a historic properties report. If the THC requests a formal report in order to fulfill the Section 106 recording of historic properties process, a formal report would then be prepared that outlines the history of the area, the construction data of the bridge, the historic significance of the bridge and whether it is eligible, meeting the established four criteria for eligibility for listing on the National Register of Historic Places (NRHP). The report would also discuss any potential impacts to the NRHP Zilker Park as a result of the rehabilitation and/or retrofitting of the bridge. The report will include the design drawings and materials proposed for the rehabilitation and retrofitting. Once the report is submitted to the City, who will then submit to the THC, the THC has 30 days to review the document and provide their comments and/or concurrence. If the THC concurs with the report, then the project can proceed without any further coordination with the THC. Time Estimate for Concurrence/Clearance: It is estimated that the process to obtain Section 106 clearance from the THC for this portion of Option 1 will take approximately three months, or 90 days after report is submitted. Section 106 Requirements and Review for Option 1 – Construction of Companion Bridge: If the City decides to construct a companion bridge next to the current Barton Springs Bridge, the purpose and need of the proposed bridge, the preliminary design, and proposed construction materials, must be presented in a written report to the THC. The report will also include an assessment as to any impacts (adverse or non-adverse) and any effects (adverse or non-adverse) as required by the Section 106 recording of historic properties process. If the THC concurs that there will be NO impacts or effects to the current bridge, then no mitigation work will be required. However, if the THC determines that there WILL be impacts and/or effects, then mitigation work will be required to document the current bridges condition and to prepare educational information for future use by the public. Section 106 mitigation measures might include a) interpretive signage in the park; b) HABS/HAER documentation of the bridge; and c) educational brochures or information to be added to the Zilker Metropolitan Park website. Time Estimate for Concurrence/Clearance: If the THC determines that there will be NO impacts and effects, it is estimated that the process to obtain Section 106 clearance from the THC for this portion of Option 1 will not take any additional time as it will be included within the original submittal of the report. If the THC determines that there will BE impacts and effects, it is estimated that the process to obtain Section 106 mitigation clearance from the THC for this portion of Option 1 will take an additional four months or 120 days after the THC’s initial concurrence of the project (time needed to prepare and complete the mitigation tasks). 3 | P a g e Option 2: Rehabilitate and Widen Existing Structure The second option presented will be to rehabilitate the existing structure and enhance the deck by widening it to incorporate wider roads, sidewalks and a bike lane on both sides. This new bridge deck option may either be placed on the existing substructure or a widened, expanded substructure as necessary. All recommended modifications must appropriately protect the character and historical significance of the original structure. This option may also include retrofit, classic-style bridge railings as noted in the first rehabilitation option. The two goals of Option 2 include: a) Widen deck for expanding roadway, bicycle, and sidewalk/pedestrian needs; and, b) Include new structural features to include superstructure and may also include additional arches/substructure. This approach will require close attention to detail, especially where new structural features, such as long outriggers, are added to the bridge to carry the wider deck. The new features should utilize forms and details that fit seamlessly with the existing bridge so that the overall look and feel of the bridge is preserved. When analyzing this option, consideration should be given to the effect of the change in overall proportions to the existing bridge. The wider deck and additional spandrel arches will change the footprint of the bridge. This change will be most noticeable to the recreational users on the creek and visitors riding on the Zilker Zephry. Section 106 Requirements and Review for Option 2: It is critical that early and continued coordination and discussion be held with the THC in order to keep the project moving in a timely basis. Prior to the creation of any designs for the rehabilitation and widening of the bridge, it is recommended that the City initiate coordination between the Texas Historic Commission (THC) (State Historic Preservation Office - SHPO). Early coordination would consist of: Meeting with the THC to discuss City’s purpose and need of the project; Discussion of possible options for the bridge; Discussion of what the THC perceives are the significant elements of the bridge; Discussion of any perceived impacts to the NRHP Zilker Park; Discussion of Section 106 process for mitigation of the resource; Discussion of public involvement since the bridge is within the NRHP Listed Zilker Park; and, Discussion of public meetings with Preservation Austin and residents of the Zilker neighborhood. It is recommended that the attendees for this meeting include City officials, overseeing the Bridge project, bridge engineers, bridge architect, and the architectural historian. This meeting will provide the engineers with guidance as to what the THC would prefer in terms of design for the bridge widening as well as materials to be used. 4 | P a g e While the Barton Springs Bridge is currently not listed on the NRHP, it is an element within the NRHP listed Zilker Park. Preliminary review of the Bridge and its history would indicate that the bridge would be individually eligible for listing. During the discussion with the THC, it will be asked whether the THC would like to see a formal Section 106 historic properties recording report prepared and presented, or if the THC would make the determination based on their own recommendations. If the THC requests a formal report in order to fulfill the Section 106 recording of historic properties process, a formal report would then be prepared that outlines the history of the area, the construction data of the bridge, the historic significance of the bridge and whether it is eligible, meeting the established four criteria for eligibility for listing on the National Register of Historic Places (NRHP). The report would also discuss the materials for rehabilitation and the design for widening the existing bridge. Discussion within the report will include any potential impacts to the existing bridge as well as to the NRHP Zilker Park as a result of the rehabilitation and widening of the bridge. Once the report is submitted to the City, who will then submit to the THC, the THC has 30 days to review the document and provide their comments and/or concurrence of the recommendations presented within the report. The report will also include an assessment as to any impacts (adverse or non-adverse) and any effects (adverse or non-adverse) as required by the Section 106 recording of historic properties process. If the THC concurs that there will be NO impacts or effects to the current bridge, then no mitigation work will be required and the project can proceed without further coordination. However, if the THC determines that there WILL be impacts and/or effects, then mitigation work will be required to document the current bridges condition and to prepare educational information for future use by the public. Section 106 mitigation measures might include a) interpretive signage in the park; b) HABS/HAER documentation of the bridge; and c) educational brochures or information to be added to the Zilker Metropolitan Park website. Time Estimate for Concurrence /Clearance: If the THC determines that there will be NO impacts and effects, it is estimated that the process to obtain Section 106 clearance from the THC for this Option will take 90 days. If the THC determines that there will be impacts and effects, it is estimated that the process to obtain Section 106 review and mitigation clearance from the THC for this Option will take and additional seven months from the THC’s initial concurrence. Option 3: Replacement of the Existing Bridge The third option would call for the complete replacement of the bridge. The two goals of Option 3 include: a) Demolition of existing bridge; and b) Replacing existing bridge with wider bridge to accommodate roadway, bicycle, and sidewalk/pedestrian needs. 5 | P a g e Recommendations for Section 106 Review: It is critical that early and continued coordination and discussion be held with the THC in order to keep the project moving in a timely basis. Prior to the creation of any designs for the new bridge, it is recommended that the City initiate coordination between the Texas Historic Commission (THC) (State Historic Preservation Office - SHPO). Early coordination would consist of: Meeting with the THC to discuss City’s purpose and need of the project; Discussion of possible options for the bridge; Discussion of what the THC perceives are the significant elements of the bridge; Discussion of any perceived impacts to the NRHP Zilker Park; Discussion of Section 106 process for mitigation of the resource; Discussion of public involvement since the bridge is within the NRHP Listed Zilker Park; and, Discussion of public meetings with Preservation Austin and residents of the Zilker neighborhood. It is recommended that the attendees for this meeting include City officials, overseeing the Bridge project, bridge engineers, bridge architect, and the architectural historian. This meeting will also provide the bridge engineers with guidance as to what the THC would prefer in terms of bridge design and materials. While the Barton Springs Bridge is currently not listed on the NRHP, it is an element within the NRHP listed Zilker Park. Preliminary review of the Bridge and its history would indicate that the bridge would be individually eligible for listing. During the discussion with the THC, it will be asked whether the THC would like to see a formal Section 106 historic properties recording report prepared and presented, or if the THC would make the determination based on their own recommendations. If the THC requests a formal report in order to fulfill the Section 106 recording of historic properties process, the City is advised to hire an architectural historian who specializes in the Section 106 process. A formal report would then be prepared that outlines the history of the area, the construction data of the bridge, the historic significance of the bridge and whether it is eligible, meeting the established four criteria for eligibility for listing on the National Register of Historic Places (NRHP). The report would also discussion of the design and the materials for the new bridge. Discussion within the report will include any potential impacts to the NRHP Zilker Park as a result of the rehabilitation and widening of the bridge. Once the report is submitted to the City, who will then submit to the THC, the THC has 30 days to review the document and provide their comments and/or concurrence of the recommendations presented within the report. The report will also include an assessment as to any impacts (adverse or non-adverse) and any effects (adverse or non-adverse) as required by the Section 106 recording of historic properties process. If the THC determines that there WILL be impacts and/or effects, then mitigation work 6 | P a g e will be required to document the current bridges condition and to prepare educational information for future use by the public. Section 106 mitigation measures might include a) interpretive signage in the park; b) HABS/HAER documentation of the bridge; and c) educational brochures or information to be added to the Zilker Metropolitan Park website. Time Estimate for Concurrence /Clearance: Since this option requires the removal and replacement of the bridge, the THC will determine that there will be adverse impacts and effects to both the bridge and the Zilker Park. It is estimated that the process to obtain Section 106 review and mitigation clearance from the THC for this Option will take an additional eight months from the THC’s initial concurrence. 7 | P a g e Exhibit 1: Zilker Park National Historic Register Boundary Map Exhibit 2: 1925 Existing Barton Creek Bridge Plans Exhibit 3: 1945 Barton Creek Bridge Widening Plans A-2 - Bridge Inspection Report – Jan 2017 A-3 - Traffic Memo – Jan 2018 URS Corporation An Company URS Corporation 9400 Amberglen Boulevard Austin TX, 78729 aecom.com Project Name: Barton Springs Road Bridge Paulinda Lanham, PMP To: Public Works Department, Project Management Division City of Austin 1/30/18 Project Ref: 60493733 Date: 1/30/18 Technical Memorandum Subject: Barton Springs Road Bridge – Traffic Analysis This technical memorandum summarizes traffic analysis at the intersection of Barton Springs Road and Robert E Lee Road as part of the Barton Springs Road Bridge project. Table of Contents Introduction .............................................................................................................................................................. 2 Methodology ............................................................................................................................................................ 3 Existing Geometry ................................................................................................................................................... 4 Traffic Volumes ........................................................................................................................................................ 5 Intersection LOS Analysis ........................................................................................................................................ 8 Recommendations ................................................................................................................................................... 9 Appendix A - Traffic Counts Appendix B - Synchro Reports URS Corporation An Company 1/9 Technical Memorandum Barton Springs Road Bridge – Traffic Analysis Existing Geometry The following are the lane configurations for each approach at the T-intersection of Barton Springs Road and Robert E Lee Road: Northbound Robert E Lee Road: one left turn lane and one right turn bay with 40’ of storage; Eastbound Barton Springs Road: one through lane and one shared through-right turn lane; Westbound Barton Springs Road: two through lanes and one left turn bay with 260’ of storage; Crosswalks: western and southern legs; Sidewalks: west side of southern leg, narrow on both sides of bridge on western leg, standard on both sides of eastern leg; and Bicycle: lanes on both sides of eastern leg, no bicycle lanes on southern leg and western leg immediately west of intersection. URS Corporation An Company 4/9 Technical Memorandum Barton Springs Road Bridge – Traffic Analysis Traffic Volumes Existing turning movement count (TMC) data was collected during the AM and PM peak periods in November 2017. The count reports are in Appendix A and also include bicycle and pedestrian counts. On the day of intersection counts, the weather was fair (77°F / no rain), and the typical bicycle and pedestrian traffic did not significantly impact intersection operations. The lane configurations and existing AM and PM traffic counts are shown in Figure 2 and Figure 3. 2020 and 2040 projected traffic counts are presented in Figure 4 through Figure 7. Figure 2: Existing AM Peak Hour Turning Movement Counts Figure 3: Existing PM Peak Hour Turning Movement Counts URS Corporation An Company 5/9 Technical Memorandum Barton Springs Road Bridge – Traffic Analysis Figure 4: 2020 AM Peak Hour Turning Movement Counts Figure 5: 2020 PM Peak Hour Turning Movement Counts URS Corporation An Company 6/9 Technical Memorandum Barton Springs Road Bridge – Traffic Analysis Figure 6: 2040 AM Peak Hour Turning Movement Counts Figure 7: 2040 PM Peak Hour Turning Movement Counts URS Corporation An Company 7/9 Technical Memorandum Barton Springs Road Bridge – Traffic Analysis Recommendations URS recommends construction of both the northbound and eastbound right turn bays at the intersection of Robert E Lee Road and Barton Springs Road. The turn bay storage lengths used in the analysis were 130’ for the northbound approach and 250’ for the eastbound approach. The turn bays will improve vehicle operations at the intersection by reducing delay for vehicles on those approaches during peak hour traffic. All proposed design for the project will include safe design for bicycle and pedestrian crossings and transitions. Additional benefits from the right turn bays include additional roadway space for maintenance of traffic during bridge construction and additional pavement and flexibility for special event traffic control operations for the many special events that occur at Zilker Park such as the Austin City Limits Festival and the Trail of Lights. The special event traffic such as buses, special event vehicles, and pedestrian traffic are in extremely high volumes, and the addition of pavement widths around this critical intersection provide more options for how to arrange the traffic patterns. URS Corporation An Company 9/9 Technical Memorandum Barton Springs Road Bridge – Traffic Analysis Appendix A – Traffic Counts C. J. Hensch & Associates Inc. 5215 Sycamore Ave. Pasadena, Texas, United States 77503 (281) 487-5417 Count Name: Barton Springs at Robert E Lee Site Code: Start Date: 11/01/2017 Page No: 1 Turning Movement Data Robert E Lee Northbound Barton Springs Rd Eastbound Barton Springs Rd Westbound Left Thru U-Turn Peds Left Right U-Turn Peds Start Time 7 00 AM 7:15 AM 7 30 AM 7:45 AM Hourly Total 8 00 AM 8:15 AM 8 30 AM 8:45 AM Hourly Total *** BREAK *** 4 00 PM 4:15 PM 4 30 PM 4:45 PM 16 17 23 13 69 20 22 24 13 79 - 48 44 51 69 Hourly Total 212 5 00 PM 5:15 PM 5 30 PM 5:45 PM Hourly Total Grand Total Approach % Total % Lights % Lights Mediums % Mediums Articulated Trucks % Articulated Trucks Bicycles on Crosswalk % Bicycles on Crosswalk Pedestrians % Pedestrians 56 78 63 58 255 615 14.8 6.9 605 98.4 10 1.6 0 0.0 - - - - 61 115 167 224 567 237 247 254 243 981 - 189 271 243 277 980 234 253 264 245 996 3524 85.1 39.3 3497 99.2 26 0.7 1 0.0 - - - - 0 0 0 0 0 0 1 0 0 1 - 0 0 0 0 0 0 1 0 2 3 4 0.1 0.0 4 100 0 0 0.0 0 0.0 - - - - 0 0 0 0 0 0 0 1 0 1 - 0 0 0 0 0 0 0 0 0 0 1 - - - - - - - - 0 0.0 1 100 0 App. Total 77 132 190 237 636 257 270 278 256 1061 - 237 315 294 346 33 63 91 130 317 108 158 108 129 503 - 22 50 49 34 27 36 87 73 223 62 60 61 66 249 - 21 34 29 26 1192 155 110 290 332 327 305 1254 4143 - 46.2 4106 99.1 36 0 9 1 0 0 - - - - 31 31 26 25 113 1088 60.7 12.1 1083 99.5 4 0.4 1 0.1 - - - - 17 28 37 39 121 703 39.3 7 8 703 100.0 0 0 0 0 0 0 - - - - 0 0 0 0 0 0 0 0 0 0 - 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 - 0 - 0 - - - - - App. Total 60 99 178 203 540 170 218 169 195 752 - 43 84 78 60 2 4 3 4 13 0 0 3 4 7 - 3 4 2 1 10 265 3 4 3 8 18 48 - - - - - - - - 13 27.1 35 72.9 48 59 63 64 234 1791 - 20.0 1786 99.7 4 0 2 1 0.1 - - - - Thru Right U-Turn Peds App. Total Int. Total 57 63 69 88 277 96 90 97 116 399 - 143 140 143 187 613 209 193 237 243 882 2171 71.7 24 2 2155 99 3 16 0.7 0 0.0 - - - - 8 22 13 19 62 19 21 37 35 112 - 57 64 86 96 303 108 80 92 101 381 858 28 3 9.6 853 99.4 4 0.5 1 0.1 - - - - 0 0 0 0 0 0 0 0 0 0 - 0 0 0 0 0 0 0 0 0 0 0 0.0 0.0 0 - 0 - 0 - - - - - 1 1 0 0 2 1 0 0 1 2 - 9 2 2 2 15 5 9 4 5 23 42 - - - - - - - - 11 26 2 31 73 8 65 85 82 107 339 115 111 134 151 511 - 200 204 229 283 916 317 273 329 344 1263 3029 - 33 8 3008 99 3 20 0.7 1 0.0 - - - - 202 316 450 547 1515 542 599 581 602 2324 - 480 603 601 689 2373 655 664 719 713 2751 8963 - - 8900 99 3 60 0.7 3 0.0 - - - - C. J. Hensch & Associates Inc. 5215 Sycamore Ave. Pasadena, Texas, United States 77503 (281) 487-5417 Count Name: Barton Springs at Robert E Lee Site Code: Start Date: 11/01/2017 Page No: 3 Turning Movement Peak Hour Data (8:00 AM) Start Time 8 00 AM 8:15 AM 8 30 AM 8:45 AM Total Approach % Total % PHF Lights % Lights Mediums % Mediums Articulated Trucks % Articulated Trucks Bicycles on Crosswalk % Bicycles on Crosswalk Pedestrians % Pedestrians Barton Springs Rd Westbound Left Thru U-Turn Peds 20 22 24 13 79 7.4 3.4 237 247 254 243 981 92.5 42.2 0 1 0 0 1 0.1 0.0 0.823 0.966 0.250 75 94.9 4 5.1 0 0.0 - - - - 970 98.9 10 1.0 1 0.1 - - - - 1 100 0 0 0.0 0 0.0 - - - - 0 0 1 0 1 - - - - - - - - - 0 0.0 1 100 0 App. Total 257 270 278 256 1061 - 45.7 0.954 1046 98.6 14 1 3 1 0.1 - - - - Robert E Lee Northbound Right U-Turn Peds Left 108 158 108 129 503 66.9 21.6 62 60 61 66 249 33.1 10.7 0 0 0 0 0 0 0 0 0 0.796 0.943 0.000 501 99.6 2 0.4 0 0 0 - - - - 249 100.0 0 0 0 0 0 0 - - - - 0 - 0 - 0 - - - - - 0 0 3 4 7 - - - - - - - - - 1 14.3 6 85.7 Barton Springs Rd Eastbound Thru Right U-Turn Peds 96 90 97 116 399 78.1 17 2 19 21 37 35 112 21 9 4.8 0 0 0 0 0 0.0 0.0 0 860 0.757 0 000 394 98.7 5 1.3 0 0.0 - - - - 109 97 3 3 2.7 0 0.0 - - - - 0 - 0 - 0 - - - - - 1 0 0 1 2 - - - - - - - - - 0 0.0 2 100.0 App. Total 170 218 169 195 752 - 32.4 0 862 750 99.7 2 0 3 0 0 0 - - - - App. Total 115 111 134 151 511 - 22 0 0 846 503 98.4 8 1.6 0 0.0 - - - - Int. Total 542 599 581 602 2324 - - 0 965 2299 98 9 24 1.0 1 0.0 - - - - C. J. Hensch & Associates Inc. 5215 Sycamore Ave. Pasadena, Texas, United States 77503 (281) 487-5417 Count Name: Barton Springs at Robert E Lee Site Code: Start Date: 11/01/2017 Page No: 5 Turning Movement Peak Hour Data (5:00 PM) Start Time 5 00 PM 5:15 PM 5 30 PM 5:45 PM Total Approach % Total % PHF Lights % Lights Mediums % Mediums Articulated Trucks % Articulated Trucks Bicycles on Crosswalk % Bicycles on Crosswalk Pedestrians % Pedestrians Barton Springs Rd Westbound Left Thru U-Turn Peds 56 78 63 58 255 20.3 9.3 234 253 264 245 996 79.4 36.2 0 1 0 2 3 0.2 0.1 0.817 0.943 0.375 253 99.2 2 0.8 0 0.0 - - - - 993 99.7 3 0.3 0 0.0 - - - - 3 100 0 0 0.0 0 0.0 - -- - - 0 0 0 0 0 - - - - - - - - - 0 0 - Robert E Lee Northbound Left Right U-Turn Peds 31 31 26 25 113 48.3 4.1 17 28 37 39 121 51.7 4.4 0 0 0 0 0 0 0 0 0 0.911 0.776 0.000 113 121 100.0 100.0 0 0 0 0 0 0 - - - - 0 0 0 0 0 0 - - - - 0 - 0 - 0 - - - - - 3 4 3 8 18 - - - - - - - - - 4 22.2 14 77.8 App. Total 290 332 327 305 1254 - 45.6 0.944 1249 99.6 5 0.4 0 0 0 - - - - Barton Springs Rd Eastbound Thru Right U-Turn Peds App. Total 48 59 63 64 234 - 8 5 209 193 237 243 882 69 8 32.1 108 80 92 101 381 30 2 13 8 0 0 0 0 0 0.0 0.0 0.914 0 907 0 882 0 000 234 100.0 0 0 0 0 0 0 - - - - 880 99 8 2 0.2 0 0.0 - - - - 381 100.0 0 0.0 0 0.0 - - - - 0 - 0 - 0 - - - - - App. Total 317 273 329 344 Int. Total 655 664 719 713 5 9 4 5 23 1263 2751 - - - - - - - - - 4 17.4 19 82 6 - 45 9 0 918 1261 99 8 2 0.2 0 0.0 - - - - - - 0 957 2744 99.7 7 0.3 0 0.0 - - - - Technical Memorandum Barton Springs Road Bridge – Traffic Analysis Appendix B – Synchro Reports Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd Existing AM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS Approach Delay EBT EBR WBL WBT NBL NBR 399 399 1900 0.95 0.99 0.964 3391 3391 34 35 928 18.1 0.86 464 611 NA 2 45.0 52.0 38.5% 46.0 4.0 2.0 0.0 6.0 Lag Yes 7.0 16.0 0 46.0 0.34 0.52 35.4 0.0 35.4 D 35.4 79 79 1900 260 1 25 1.00 1.00 0.950 1770 0.269 501 112 112 1900 0 0 0.95 0 0 Yes 2 1 981 981 1900 0.95 3539 3539 35 736 14.3 0.82 96 0.97 1011 0.76 147 0 503 503 1900 0 1 25 1.00 1.00 0.950 1770 0.950 1763 30 1481 33.7 6 0.80 629 249 249 1900 40 1 1.00 0.98 0.850 1583 1559 Yes 64 6 1 0.94 265 4 20.0 68.0 20.0 67.0 1011 NA 6 96 pm+pt 1 6 10.0 15.0 629 265 Prot pm+ov 1 4 10.0 15.0 11.1% 49.6% 50.4% 11.1% 10.0 4.0 1.0 0.0 5.0 Lead Yes 10.0 4.0 1.0 0.0 5.0 Lead Yes 63.0 4.0 1.0 0.0 5.0 61.0 4.0 2.0 0.0 6.0 62.0 0.46 0.30 23.5 0.0 23.5 C 61.0 0.45 0.63 30.6 0.0 30.6 C 30.0 63.0 0.47 0.76 37.2 0.0 37.2 D 29.6 73.0 0.54 0.30 11.8 0.0 11.8 B Barton Springs Road Bridge 11/15/2017 Existing AM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd Existing AM 12/12/2017 Lane Group Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT D 212 256 848 1177 0 0 0 0.52 EBR WBL WBT C 351 425 656 47 75 260 324 0 0 0 0.30 1599 0 0 0 0.63 NBL C 447 499 1401 826 0 0 0 0.76 NBR 82 134 40 874 0 0 0 0.30 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 62 (46%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 90 Control Type: Pretimed Maximum v/c Ratio: 0.76 Intersection Signal Delay: 31.1 Intersection Capacity Utilization 64.7% Analysis Period (min) 15 Intersection LOS: C ICU Level of Service C Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 Existing AM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd Existing PM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS Approach Delay EBT EBR WBL WBT NBL NBR 381 381 1900 0 0 0.95 0 0 Yes 19 4 0.88 433 0 882 882 1900 0.95 0.98 0.954 3295 3295 67 35 928 18.1 0.91 969 1402 NA 2 45.0 65.0 48.1% 59.0 4.0 2.0 0.0 6.0 Lead Yes 7.0 16.0 0 59.0 0.44 0.95 49.1 0.0 49.1 D 49.1 255 255 1900 260 1 25 1.00 0.950 1770 0.062 115 996 996 1900 0.95 3539 3539 35 736 14.3 1 0.82 311 0.94 1060 113 113 1900 0 1 25 1.00 0.98 0.950 1770 0.950 1736 30 1481 33.7 14 0.91 124 121 121 1900 40 1 1.00 0.98 0.850 1583 1547 Yes 50 14 4 0.78 155 4 20.0 35.0 60.0 100.0 1060 NA 6 311 pm+pt 1 6 25.0 35.0 124 155 Prot pm+ov 1 4 25.0 35.0 25.9% 74.1% 25.9% 25.9% 30.0 4.0 1.0 0.0 5.0 Lag Yes 30.0 4.0 1.0 0.0 5.0 Lag Yes 30.0 4.0 1.0 0.0 5.0 94.0 4.0 2.0 0.0 6.0 95.0 0.70 0.69 49.6 0.0 49.6 D 94.0 0.70 0.43 9.5 0.0 9.5 A 18.6 30.0 0.22 0.32 46.6 0.0 46.6 D 28.6 60.0 0.44 0.21 14.2 0.0 14.2 B Barton Springs Road Bridge 11/15/2017 Existing PM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd Existing PM 12/12/2017 Lane Group Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT D 592 #757 848 1477 0 0 0 0.95 EBR WBL WBT B 193 233 656 196 265 260 448 0 0 0 0.69 2464 0 0 0 0.43 NBL C 92 152 1401 393 0 0 0 0.32 NBR 50 76 40 723 0 0 0 0.21 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 32 (24%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 90 Control Type: Pretimed Maximum v/c Ratio: 0.95 Intersection Signal Delay: 33.5 Intersection Capacity Utilization 72.9% Analysis Period (min) 15 # 95th percentile volume exceeds capacity, queue may be longer. Queue shown is maximum after two cycles. Intersection LOS: C ICU Level of Service C Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 Existing PM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 No Build AM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 399 399 1900 0.95 0.99 0.964 3391 3391 33 35 928 18.1 79 79 1900 260 1 25 1.00 1.00 0.950 1770 0.230 428 112 112 1900 0 0 0.95 0 0 Yes 981 981 1900 0.95 3539 3539 35 736 14.3 503 503 1900 0 1 25 1.00 1.00 0.950 1770 0.950 1763 249 249 1900 40 1 1.00 0.98 0.850 1583 1559 Yes 68 30 1481 33.7 6 2 1 6 1 0.86 0.94 105% 105% 105% 105% 105% 105% 278 1062 0.80 0.82 0.76 0.97 155 487 101 660 0 642 NA 2 45.0 48.0 35.6% 42.0 4.0 2.0 0.0 6.0 Lag Yes 7.0 16.0 0 42.0 0.31 0.60 39.9 0.0 39.9 D 4 20.0 73.0 20.0 62.0 1062 NA 6 101 pm+pt 1 6 10.0 14.0 660 278 Prot pm+ov 1 4 10.0 14.0 10.4% 45.9% 54.1% 10.4% 9.0 4.0 1.0 0.0 5.0 Lead Yes 9.0 4.0 1.0 0.0 5.0 Lead Yes 68.0 4.0 1.0 0.0 5.0 56.0 4.0 2.0 0.0 6.0 57.0 0.42 0.37 28.1 0.0 28.1 C 56.0 0.41 0.72 36.5 0.0 36.5 D 68.0 0.50 0.74 32.8 0.0 32.8 C 77.0 0.57 0.30 10.3 0.0 10.3 B Barton Springs Road Bridge 11/15/2017 2020 No Build AM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 No Build AM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 39.9 D 237 285 848 1077 0 0 0 0.60 EBR WBL WBT 35.8 D 405 487 656 54 84 260 270 0 0 0 0.37 1468 0 0 0 0.72 NBL 26.1 C 446 493 1401 891 0 0 0 0.74 NBR 80 129 40 920 0 0 0 0.30 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 62 (46%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 90 Control Type: Pretimed Maximum v/c Ratio: 0.74 Intersection Signal Delay: 33.5 Intersection Capacity Utilization 66.9% Analysis Period (min) 15 Intersection LOS: C ICU Level of Service C Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2020 No Build AM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 No Build PM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 882 882 1900 0.95 0.98 0.954 3296 3296 83 35 928 18.1 255 255 1900 260 1 25 1.00 0.950 1770 0.086 160 381 381 1900 0 0 0.95 0 0 Yes 996 996 1900 0.95 3539 3539 35 736 14.3 113 113 1900 0 1 25 1.00 0.97 0.950 1770 0.950 1711 121 121 1900 40 1 1.00 0.97 0.850 1583 1541 Yes 81 30 1481 33.7 14 1 19 4 0.88 14 4 0.91 0.78 105% 105% 105% 105% 105% 105% 163 1018 1113 0.91 0.82 0.94 130 455 327 0 1473 NA 2 45.0 79.0 58.5% 73.0 4.0 2.0 0.0 6.0 Lead Yes 7.0 16.0 0 73.0 0.54 0.81 28.2 0.0 28.2 C 4 20.0 22.0 60.0 113.0 1113 NA 6 327 pm+pt 1 6 25.0 34.0 130 163 Prot pm+ov 1 4 25.0 34.0 25.2% 83.7% 16.3% 25.2% 29.0 4.0 1.0 0.0 5.0 Lag Yes 29.0 4.0 1.0 0.0 5.0 Lag Yes 107.0 4.0 2.0 0.0 6.0 17.0 4.0 1.0 0.0 5.0 108.0 0.80 0.69 42.9 0.0 42.9 D 107.0 0.79 0.40 4.7 0.0 4.7 A 17.0 0.13 0.59 67.2 0.0 67.2 E 46.0 0.34 0.28 15.6 0.0 15.6 B Barton Springs Road Bridge 11/15/2017 2020 No Build PM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 No Build PM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 28.2 C 511 614 848 1820 0 0 0 0.81 EBR WBL WBT 13.4 B 131 156 656 171 239 260 473 0 0 0 0.69 2804 0 0 0 0.40 NBL 38.5 D 109 179 1401 222 0 0 0 0.59 NBR 47 77 40 587 0 0 0 0.28 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 32 (24%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 90 Control Type: Pretimed Maximum v/c Ratio: 0.81 Intersection Signal Delay: 22.5 Intersection Capacity Utilization 75.5% Analysis Period (min) 15 Intersection LOS: C ICU Level of Service D Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2020 No Build PM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 Build AM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 79 79 1900 260 1 25 1.00 1.00 0.950 1770 0.329 612 399 399 1900 0.95 112 112 1900 250 1 1.00 0.97 0.850 3539 1583 1543 Yes 155 3539 35 928 18.1 981 981 1900 0.95 3539 3539 35 736 14.3 503 503 1900 0 1 25 1.00 1.00 0.950 1770 0.950 1763 249 249 1900 130 1 1.00 0.98 0.850 1583 1559 Yes 136 30 1481 33.7 6 2 1 6 1 0.86 0.94 105% 105% 105% 105% 105% 105% 278 1062 0.80 0.82 0.76 0.97 155 101 660 487 155 1062 NA 6 101 Perm pm+pt 1 6 20.0 20.0 10.0 74.0 61.0 13.0 9.6% 45.2% 54.8% 69.0 55.0 4.0 4.0 1.0 2.0 0.0 0.0 5.0 6.0 4 660 278 Prot pm+ov 1 4 10.0 13.0 9.6% 8.0 4.0 1.0 0.0 5.0 Lead Yes 8.0 4.0 1.0 0.0 5.0 Lead Yes 487 NA 2 45.0 48.0 2 45.0 48.0 35.6% 35.6% 42.0 4.0 2.0 0.0 6.0 Lag Yes 7.0 16.0 0 42.0 0.31 0.26 6.1 0.0 6.1 A 42.0 4.0 2.0 0.0 6.0 Lag Yes 7.0 16.0 0 42.0 0.31 0.44 38.7 0.0 38.7 D 56.0 0.41 0.31 27.4 0.0 27.4 C 55.0 0.41 0.74 37.7 0.0 37.7 D 69.0 0.51 0.73 31.7 0.0 31.7 C 77.0 0.57 0.29 6.9 0.0 6.9 A Barton Springs Road Bridge 11/15/2017 2020 Build AM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 Build AM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 30.8 C 179 220 848 1101 0 0 0 0.44 EBR 0 27 250 586 0 0 0 0.26 WBL WBT 36.8 D 410 494 656 54 85 260 322 0 0 0 0.31 1441 0 0 0 0.74 NBL 24.3 C 439 485 1401 904 0 0 0 0.73 NBR 51 96 130 949 0 0 0 0.29 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 62 (46%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 90 Control Type: Pretimed Maximum v/c Ratio: 0.74 Intersection Signal Delay: 31.1 Intersection Capacity Utilization 66.9% Analysis Period (min) 15 Intersection LOS: C ICU Level of Service C Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2020 Build AM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 Build PM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 255 255 1900 260 1 25 1.00 0.950 1770 0.185 345 882 882 1900 0.95 381 381 1900 250 1 1.00 0.92 0.850 3539 1583 1460 Yes 455 3539 35 928 18.1 996 996 1900 0.95 3539 3539 35 736 14.3 113 113 1900 0 1 25 1.00 0.97 0.950 1770 0.950 1724 121 121 1900 130 1 1.00 0.98 0.850 1583 1545 Yes 55 30 1481 33.7 14 1 19 4 0.88 14 4 0.91 0.78 105% 105% 105% 105% 105% 105% 163 1018 1113 0.91 0.82 0.94 327 130 455 4 455 20.0 27.0 45.0 70.0 60.0 108.0 2 45.0 70.0 1113 NA 6 1018 NA 2 327 Perm pm+pt 1 6 25.0 38.0 130 163 Prot pm+ov 1 4 25.0 38.0 51.9% 51.9% 28.1% 80.0% 20.0% 28.1% 33.0 4.0 1.0 0.0 5.0 Lag Yes 33.0 4.0 1.0 0.0 5.0 Lag Yes 102.0 4.0 2.0 0.0 6.0 22.0 4.0 1.0 0.0 5.0 64.0 4.0 2.0 0.0 6.0 Lead Yes 7.0 16.0 0 64.0 0.47 0.61 28.1 0.0 28.1 C 64.0 4.0 2.0 0.0 6.0 Lead Yes 7.0 16.0 0 64.0 0.47 0.49 3.7 0.0 3.7 A 103.0 0.76 0.54 24.1 0.0 24.1 C 102.0 0.76 0.42 6.4 0.0 6.4 A 22.0 0.16 0.45 56.8 0.0 56.8 E 55.0 0.41 0.24 16.1 0.0 16.1 B Barton Springs Road Bridge 11/15/2017 2020 Build PM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2020 Build PM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 20.6 C 339 410 848 1677 0 0 0 0.61 EBR 0 51 250 931 0 0 0 0.49 WBL WBT 10.5 B 160 192 656 73 122 260 611 0 0 0 0.54 2673 0 0 0 0.42 NBL 34.2 C 104 171 1401 288 0 0 0 0.45 NBR 56 84 130 671 0 0 0 0.24 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 32 (24%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 90 Control Type: Pretimed Maximum v/c Ratio: 0.61 Intersection Signal Delay: 17.3 Intersection Capacity Utilization 62.1% Analysis Period (min) 15 Intersection LOS: B ICU Level of Service B Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2020 Build PM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 No Build AM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 399 399 1900 0.95 0.99 0.964 3391 3391 32 35 928 18.1 79 79 1900 260 1 25 1.00 0.950 1770 0.089 166 112 112 1900 0 0 0.95 0 0 Yes 981 981 1900 0.95 3539 3539 35 736 14.3 503 503 1900 0 1 25 1.00 1.00 0.950 1770 0.950 1763 249 249 1900 40 1 1.00 0.98 0.850 1583 1559 Yes 44 30 1481 33.7 6 1 2 6 1 0.86 0.94 151% 151% 151% 151% 151% 151% 400 1527 0.80 0.82 0.76 0.97 701 223 145 949 0 924 NA 2 45.0 46.0 34.1% 40.0 4.0 2.0 0.0 6.0 Lag Yes 7.0 16.0 0 40.0 0.30 0.90 56.6 0.0 56.6 E 4 20.0 62.0 20.0 73.0 1527 NA 6 145 pm+pt 1 6 10.0 16.0 949 400 Prot pm+ov 1 4 10.0 16.0 11.9% 45.9% 54.1% 11.9% 11.0 4.0 1.0 0.0 5.0 Lead Yes 11.0 4.0 1.0 0.0 5.0 Lead Yes 68.0 4.0 1.0 0.0 5.0 56.0 4.0 2.0 0.0 6.0 57.0 0.42 0.72 48.7 0.0 48.7 D 56.0 0.41 1.04 73.3 0.0 73.3 E 68.0 0.50 1.07 82.0 0.0 82.0 F 79.0 0.59 0.43 13.0 0.0 13.0 B Barton Springs Road Bridge 11/15/2017 2040 No Build AM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 No Build AM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 56.6 E 397 456 848 1027 0 0 0 0.90 EBR WBL WBT 71.2 E ~759 #899 656 79 #130 260 200 0 0 0 0.72 1468 0 0 0 1.04 NBL 61.6 E ~916 #952 1401 891 0 0 0 1.07 NBR 146 214 40 932 0 0 0 0.43 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 62 (46%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 110 Control Type: Pretimed Maximum v/c Ratio: 1.07 Intersection Signal Delay: 64.5 Intersection Capacity Utilization 92.2% Analysis Period (min) 15 ~ Volume exceeds capacity, queue is theoretically infinite. Queue shown is maximum after two cycles. # 95th percentile volume exceeds capacity, queue may be longer. Queue shown is maximum after two cycles. Intersection LOS: E ICU Level of Service F Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2040 No Build AM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 No Build PM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 882 882 1900 0.95 0.98 0.954 3296 3296 87 35 928 18.1 255 255 1900 260 1 25 1.00 0.950 1770 0.049 91 381 381 1900 0 0 0.95 0 0 Yes 996 996 1900 0.95 3539 3539 35 736 14.3 113 113 1900 0 1 25 1.00 0.96 0.950 1770 0.950 1703 121 121 1900 40 1 1.00 0.97 0.850 1583 1540 Yes 29 30 1481 33.7 14 1 19 4 0.88 14 4 0.91 0.78 151% 151% 151% 151% 151% 151% 234 1464 1600 0.91 0.82 0.94 654 470 188 0 2118 NA 2 45.0 82.0 60.7% 76.0 4.0 2.0 0.0 6.0 Lead Yes 7.0 16.0 0 76.0 0.56 1.12 89.4 0.0 89.4 F 4 20.0 20.0 60.0 115.0 1600 NA 6 470 pm+pt 1 6 25.0 33.0 188 234 Prot pm+ov 1 4 25.0 33.0 24.4% 85.2% 14.8% 24.4% 28.0 4.0 1.0 0.0 5.0 Lag Yes 28.0 4.0 1.0 0.0 5.0 Lag Yes 109.0 4.0 2.0 0.0 6.0 15.0 4.0 1.0 0.0 5.0 110.0 0.81 1.11 121.1 0.0 121.1 F 109.0 0.81 0.56 5.5 0.0 5.5 A 15.0 0.11 0.96 113.7 0.0 113.7 F 43.0 0.32 0.45 31.8 0.0 31.8 C Barton Springs Road Bridge 11/15/2017 2040 No Build PM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 No Build PM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 89.4 F ~1106 #1242 848 1893 0 0 0 1.12 EBR WBL WBT 31.7 C 213 252 656 ~421 #543 260 422 0 0 0 1.11 2857 0 0 0 0.56 NBL 68.3 E 167 #320 1401 196 0 0 0 0.96 NBR 134 173 40 519 0 0 0 0.45 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 32 (24%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 150 Control Type: Pretimed Maximum v/c Ratio: 1.12 Intersection Signal Delay: 61.6 Intersection Capacity Utilization 99.9% Analysis Period (min) 15 ~ Volume exceeds capacity, queue is theoretically infinite. Queue shown is maximum after two cycles. # 95th percentile volume exceeds capacity, queue may be longer. Queue shown is maximum after two cycles. Intersection LOS: E ICU Level of Service F Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2040 No Build PM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 Build AM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 79 79 1900 260 1 25 1.00 0.950 1770 0.184 343 399 399 1900 0.95 112 112 1900 250 1 1.00 0.97 0.850 3539 1583 1543 Yes 223 3539 35 928 18.1 981 981 1900 0.95 3539 3539 35 736 14.3 503 503 1900 0 1 25 1.00 1.00 0.950 1770 0.950 1763 249 249 1900 130 1 1.00 0.98 0.850 1583 1559 Yes 44 30 1481 33.7 6 1 2 6 1 0.86 0.94 151% 151% 151% 151% 151% 151% 400 1527 0.80 0.82 0.76 0.97 949 145 223 701 4 223 45.0 46.0 20.0 62.0 20.0 73.0 701 NA 2 2 45.0 46.0 1527 NA 6 145 Perm pm+pt 1 6 10.0 16.0 949 400 Prot pm+ov 1 4 10.0 16.0 34.1% 34.1% 11.9% 45.9% 54.1% 11.9% 11.0 4.0 1.0 0.0 5.0 Lead Yes 11.0 4.0 1.0 0.0 5.0 Lead Yes 68.0 4.0 1.0 0.0 5.0 56.0 4.0 2.0 0.0 6.0 40.0 4.0 2.0 0.0 6.0 Lag Yes 7.0 16.0 0 40.0 0.30 0.67 45.4 0.0 45.4 D 40.0 4.0 2.0 0.0 6.0 Lag Yes 7.0 16.0 0 40.0 0.30 0.36 6.1 0.0 6.1 A 57.0 0.42 0.56 33.2 0.0 33.2 C 56.0 0.41 1.04 73.3 0.0 73.3 E 68.0 0.50 1.07 82.0 0.0 82.0 F 79.0 0.59 0.43 13.0 0.0 13.0 B Barton Springs Road Bridge 11/15/2017 2040 Build AM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 Build AM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 35.9 D 284 334 848 1048 0 0 0 0.67 EBR 0 27 250 614 0 0 0 0.36 WBL WBT 69.8 E ~759 #899 656 79 115 260 261 0 0 0 0.56 1468 0 0 0 1.04 NBL 61.6 E ~916 #952 1401 891 0 0 0 1.07 NBR 146 214 130 932 0 0 0 0.43 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 62 (46%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 110 Control Type: Pretimed Maximum v/c Ratio: 1.07 Intersection Signal Delay: 59.1 Intersection Capacity Utilization 92.2% Analysis Period (min) 15 ~ Volume exceeds capacity, queue is theoretically infinite. Queue shown is maximum after two cycles. # 95th percentile volume exceeds capacity, queue may be longer. Queue shown is maximum after two cycles. Intersection LOS: E ICU Level of Service F Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2040 Build AM AECOM Synchro 9 Report Page 2 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 Build PM 12/12/2017 Lane Group Lane Configurations Traffic Volume (vph) Future Volume (vph) Ideal Flow (vphpl) Storage Length (ft) Storage Lanes Taper Length (ft) Lane Util. Factor Ped Bike Factor Frt Flt Protected Satd. Flow (prot) Flt Permitted Satd. Flow (perm) Right Turn on Red Satd. Flow (RTOR) Link Speed (mph) Link Distance (ft) Travel Time (s) Confl. Peds. (#/hr) Confl. Bikes (#/hr) Peak Hour Factor Growth Factor Adj. Flow (vph) Shared Lane Traffic (%) Lane Group Flow (vph) Turn Type Protected Phases Permitted Phases Minimum Split (s) Total Split (s) Total Split (%) Maximum Green (s) Yellow Time (s) All-Red Time (s) Lost Time Adjust (s) Total Lost Time (s) Lead/Lag Lead-Lag Optimize? Walk Time (s) Flash Dont Walk (s) Pedestrian Calls (#/hr) Act Effct Green (s) Actuated g/C Ratio v/c Ratio Control Delay Queue Delay Total Delay LOS EBT EBR WBL WBT NBL NBR 255 255 1900 260 1 25 1.00 0.950 1770 0.062 115 882 882 1900 0.95 381 381 1900 250 1 1.00 0.92 0.850 3539 1583 1461 Yes 462 3539 35 928 18.1 996 996 1900 0.95 3539 3539 35 736 14.3 113 113 1900 0 1 25 1.00 0.97 0.950 1770 0.950 1714 121 121 1900 130 1 1.00 0.98 0.850 1583 1545 Yes 15 30 1481 33.7 14 1 19 4 0.88 14 4 0.91 0.78 151% 151% 151% 151% 151% 151% 234 1464 1600 0.91 0.82 0.94 470 188 654 4 654 20.0 23.0 45.0 71.0 60.0 112.0 2 45.0 71.0 1600 NA 6 1464 NA 2 470 Perm pm+pt 1 6 25.0 41.0 188 234 Prot pm+ov 1 4 25.0 41.0 52.6% 52.6% 30.4% 83.0% 17.0% 30.4% 36.0 4.0 1.0 0.0 5.0 Lag Yes 36.0 4.0 1.0 0.0 5.0 Lag Yes 106.0 4.0 2.0 0.0 6.0 18.0 4.0 1.0 0.0 5.0 65.0 4.0 2.0 0.0 6.0 Lead Yes 7.0 16.0 0 65.0 0.48 0.86 37.4 0.0 37.4 D 65.0 4.0 2.0 0.0 6.0 Lead Yes 7.0 16.0 0 65.0 0.48 0.69 11.5 0.0 11.5 B 107.0 0.79 0.88 60.1 0.0 60.1 E 106.0 0.79 0.58 6.7 0.0 6.7 A 18.0 0.13 0.80 80.8 0.0 80.8 F 54.0 0.40 0.37 25.4 0.0 25.4 C Barton Springs Road Bridge 11/15/2017 2040 Build PM AECOM Synchro 9 Report Page 1 Lanes, Volumes, Timings 3: Robert E Lee Rd & Barton Springs Rd 2040 Build PM 12/12/2017 Lane Group Approach Delay Approach LOS Queue Length 50th (ft) Queue Length 95th (ft) Internal Link Dist (ft) Turn Bay Length (ft) Base Capacity (vph) Starvation Cap Reductn Spillback Cap Reductn Storage Cap Reductn Reduced v/c Ratio EBT 29.4 C 584 691 848 1703 0 0 0 0.86 EBR 120 244 250 943 0 0 0 0.69 WBL WBT 18.8 B 245 290 656 336 #420 260 532 0 0 0 0.88 2778 0 0 0 0.58 NBL 50.1 D 162 #284 1401 236 0 0 0 0.80 NBR 124 159 130 637 0 0 0 0.37 Other Intersection Summary Area Type: Cycle Length: 135 Actuated Cycle Length: 135 Offset: 32 (24%), Referenced to phase 2:EBT and 6:WBTL, Start of Green Natural Cycle: 90 Control Type: Pretimed Maximum v/c Ratio: 0.88 Intersection Signal Delay: 26.5 Intersection Capacity Utilization 80.9% Analysis Period (min) 15 # 95th percentile volume exceeds capacity, queue may be longer. Queue shown is maximum after two cycles. Intersection LOS: C ICU Level of Service D Splits and Phases: 3: Robert E Lee Rd & Barton Springs Rd Barton Springs Road Bridge 11/15/2017 2040 Build PM AECOM Synchro 9 Report Page 2 Appendix B - Bridge Initial Assessments B-1 - Initial Geometry - Feb 2018 B-2 - Rehabilitation Feasibility - May 2018 B-3 - Public Works Management Briefing - July 2018 B-4 - Preliminary Renderings - Sept 2018 Appendix C - Restart Assessments C-1 - Project Update – Nov 2021