The National Academies Press

Currently Skimming:

Pages 511-548

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.

From page 511... ... Appendix I Case Studies INTRODUCTION Twenty-two case studies were analyzed to support the committee's deliberations regarding needs and strategy orientation. Not necessarily representative of all Interstate needs, the case studies are illustrative examples to support reasonable judgements regarding needs analysis. Read the entire page →
From page 512... ... 512 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM TABLE I-1 Selection Criteria for Case Studies Geography Users Improvement Strategies • Urban/Metro • Interurban • Rural • Commercial/Freight • Passenger • Preservation • Operations • Capacity • Technology TABLE I-2 Brief Description of Case Study Projects, Plans Projects/Plans Description and Rationale CA, Bay Area Express Lanes The Bay Area is planning a 550-mile network of Express Lanes by 2035 to improve the operational efficiency. Metropolitan Transportation Commission (MTC) Read the entire page →
From page 513... ... APPENDIX I 513 Projects/Plans Description and Rationale CO, SMART 25 Managed Motorways, Denver This $7 million Managed Motorways demonstration project will add sensors to the lanes on the northbound side of 13 miles of I-25 south of downtown Denver. This stretch has 17 points of access or egress, including the interchange with E-470. Read the entire page →
From page 514... ... 514 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Projects/Plans Description and Rationale KY-IN, I-65 Ohio River Bridges, Louisville The primary intent of this project is to address inadequate cross-river system linkage opportunities and relating congestion impacts on the Kennedy bridge and interchange, given that no viable alternatives are available for at least 50 miles on either sides along the Ohio River. This project improves cross-river mobility through the construction of a new bridge, interchange reconfiguration, and freeway rerouting through a by-pass roadway. Read the entire page →
From page 515... ... APPENDIX I 515 Projects/Plans Description and Rationale PA, I-70 New Stanton Interchange Two substandard interchanges on the I-70 corridor in New Stanton, Pennsylvania, were consolidated into a single modern interchange with a double roundabout configuration. This interchange, which is located about 1 mile away from the I-76/I-70 system interchange, was constructed in response to higher crash rates, poor LOS at ramps, and outdated design standards. Read the entire page →
From page 516... ... 516 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Projects/Plans Description and Rationale TX, US 75 Integrated Corridor Management, Dallas The 28-mile stretch of US 75 (which effectively operates as an interstate) between Plano and downtown Dallas was selected as one of two Integrated Corridor Management demonstration sites in the United States. Read the entire page →
From page 517... ... APPENDIX I 517 Projects/Plans Description and Rationale WA, I-405 Corridor, Seattle Originally intended as a bypass route, the 30-mile corridor of I-405 in east suburban Seattle is Washington State's second most heavily traveled expressway. High growth in population, employment, and traffic congestion characterize the largely suburban region that surrounds the corridor. Read the entire page →
From page 518... ... 518 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM The case studies were grouped into four "case study categories" based on the geographical, user characteristics, and improvement strategies. • Urban Corridors/Regions: This category of case studies explores the needs of Interstates in some of the top metropolitan areas of the nation. Read the entire page →
From page 519... ... APPENDIX I 519 multiple high-volume roadways (e.g., more than one Interstate or U.S. route) Read the entire page →
From page 520... ... 520 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM roadways to Interstate design standards in rural areas. I-75 is one of the nation's most heavily traveled truck freight corridors and required reconstruction to correct design deficiencies and reduce the maintenance burden. Read the entire page →
From page 521... ... APPENDIX I 521 either qualitative or quantitative terms? The performance metrics that are being evaluated include, but not limited to, metrics relating to travel demand, travel mode, mobility, and safety. Read the entire page →
From page 522... ... 522 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM the need to meet greenhouse gas–reduction targets are both cited as drivers behind the San Francisco Bay Area Express Lanes network. The documentation for the I-15 Integrated Corridor Management project in San Diego also cites housing growth as a driver, especially in less expensive locations in southeast Riverside County, which increases commuter volumes in the corridor. Read the entire page →
From page 523... ... APPENDIX I 523 77 south of Corpus Christi, Texas, and the I-85 Kia Boulevard Interchange in Georgia. The Future I-11 project will expand existing rural capacity, while the US 77 will replace a four-lane highway in kind with a four-lane Interstate facility. Read the entire page →
From page 524... ... 524 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM involving the replacement or upgrade of older Interstate facilities that do not comply with current design standards. This includes the reconstruction of I-75 in rural Allen County, Ohio, the I-195 Iway project in Providence, Rhode Island, the I-70 New Stanton Interchange in Pennsylvania, and the widening and reconstruction of I-35 from Waco to West in Texas. Read the entire page →
From page 525... ... APPENDIX I 525 Other Drivers and Deficiencies Constraints to highway widening is cited as a deficiency with the I-15 project in Utah, as are the impacts of highway widenings with the Bay Area Express Lane Network. As a result, to the maximum extent possible, the Bay Area express lane network will be created by converting existing HOV facilities to high occupancy toll (HOT) Read the entire page →
From page 526... ... 526 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM (ETL) additions that include HOV/general purpose (GP) Read the entire page →
From page 527... ... APPENDIX I 527 in real time through sophisticated algorithms (managed motorways) Read the entire page →
From page 528... ... 528 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Light rail transit also opened along the corridor in 1998 and a concurrent flow HOV lane in 2007. Continued population and employment growth -- the Dallas region has been adding roughly 1 million people every 7 to 8 years -- has driven a need for further improvement, but without any possibility of further corridor expansion, integrated corridor management incorporating the existing freeway, light rail, and parallel arterials became an operational solution worth investigating. Read the entire page →
From page 529... ... APPENDIX I 529 Network Planning and Regional Collaboration Urban improvement approaches at the regional scale suggest several observations about network planning and regional collaboration. Here it is often difficult or impractical to isolate deficiencies and improvements at the Interstate corridor level. Read the entire page →
From page 530... ... 530 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM all partners based on the ICM system's decision support system's recommendation. Incremental Approaches Generally urban improvements with a capacity element are expensive and technically or politically challenging. Read the entire page →
From page 531... ... APPENDIX I 531 Roadway Reconstruction Costs The roadway reconstruction costs in small urbanized (population between 50,000 and 200,000) and large urbanized (population greater than 200,000) Read the entire page →
From page 532... ... 532 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM TABLE I-5 Predominant Improvement Strategies in Interurban and Freight Corridor Case Studies Selected Interurban/Freight Corridor Case Studies Capacity Improvement Approaches I-65 Ohio River Bridges Downtown Crossing: Building a new I-65 bridge with six NB lanes (Segment 2) Reconfiguration of Kennedy Interchange (I-64, I-65 and I-71) Read the entire page →
From page 533... ... APPENDIX I 533 Among the case study projects in rural areas (population less than 5,000) , the average cost of reconstructing a lane is estimated at $1.3 million per mile, while adding a lane is estimated at $2.8 million per mile. Read the entire page →
From page 534... ... 534 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM The interchange reconstruction and reconfiguration projects were predominantly driven by capacity, operational and structural needs in response to substandard or outdated design standards, higher V/C, poor level of service, higher crash rates, and structural deficiencies. Depending on the needs, these projects may entail a wide range of activities, such as reconfiguration and localized improvements, widening, structure replacement, realignment or relocation, and major improvements to intersecting roads. Read the entire page →
From page 535... ... APPENDIX I 535 than $100 million. (Four selected system interchanges from three case study projects ranged between $72 and $600 million.) Read the entire page →
From page 536... ... 536 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM reconstruction was required to address recurring issues deep within the pavement structure. Among projects in rural and small urban areas that involved widening or reconstruction, the cost of pavement installation was approximately $1.3 million per mile. Read the entire page →
From page 537... ... APPENDIX I 537 of structural and functional adequacy of the bridge. The technical study, which involved detailed structural, life-cycle cost and risk analysis of 12 different scenarios, has provided a template for MnDOT to make optimal life-cycle based decisions. Read the entire page →
From page 538... ... 538 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM to physically (trip diversion to alternative routes or modes) or temporally (shift in trip time of day) Read the entire page →
From page 539... ... APPENDIX I 539 FORECASTED FUTURE PERFORMANCE Travel Demand The case studies gathered information on both travel demand and available metrics related to mobility, travel mode share, and safety. Travel demand, in terms of average daily traffic or VMT, is expected to grow annually by geography (see Table I-8) Read the entire page →
From page 540... ... 540 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM Mobility Urban Corridors/Regions Mobility metrics reported for urban corridors focused predominantly on peak hour throughput and travel time. These metrics were generally derived using microsimulation models such as CORSIM and VISSIM. Read the entire page →
From page 541... ... APPENDIX I 541 The managed lanes are expected to carry a significant share of the vehicle throughput, particularly during the peak hour periods. The peak hour vehicle throughput indicate a share of 70:30 on general purpose and express lanes on the South East Florida Express Lane Network, 67:33 on I-66 and 45:40 on the I-15 corridor. Read the entire page →
From page 542... ... 542 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM TABLE I-10 Mobility Improvement Metrics -- ICM and Managed Motorways Demonstrations Mobility: Person-Hours Traveled/Year Improved Versus Worsened Travel Times (Differential) Reliability: Buffer Time(s) Read the entire page →
From page 543... ... APPENDIX I 543 Interurban/Freight Corridors Mobility metrics reported for interurban/freight corridors included volume/ capacity ratio, travel time and speed, and intersection level of service. For these case studies, the proposed capacity expansion strategies are expected to bring immediate improvements in freeway and interchange LOS. Read the entire page →
From page 544... ... 544 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM 2006 to 2008 (construction took place in 2012) Read the entire page →
From page 545... ... APPENDIX I 545 • Traffic Simulation Models -- Microsimulation models, including VISSIM and CORSIM, were used to simulate traffic flow and develop mobility metrics for I-66, I-405, I-65 (Kennedy Interchange) , and I-80 connected vehicle projects. Read the entire page →
From page 546... ... 546 NATIONAL COMMITMENT TO THE INTERSTATE HIGHWAY SYSTEM TABLE I-11 Summary of Project Costs Case Study Cost Estimates Urban Corridors/Regions Express Toll Lanes I-405 Express Toll Lanes $15.1 million/lane-mile (new ETL, ROW not included, includes ramps/interchanges) $3.1 million/lane-mile (HOV-to-ETL conversion) Read the entire page →
From page 547... ... APPENDIX I 547 Case Study Cost Estimates I-65 Ohio River Bridges $600.3 million (I-65/I-64 Kennedy system interchange) Read the entire page →

From page 511...

... Appendix I Case Studies INTRODUCTION Twenty-two case studies were analyzed to support the committee's deliberations regarding needs and strategy orientation. Not necessarily representative of all Interstate needs, the case studies are illustrative examples to support reasonable judgements regarding needs analysis.