DRAFT

Draft Purpose and Need Statement

As part of the Environmental Review Process for I-515/US 95/US 93 Downtown Access Project

Federal Highway Administration, Division Nevada Department of Transportation

NDOT Project Number 74291 FHWA Project Number SPI-515-1(040)

May 2020

I-515 Downtown Access Project Draft Purpose and Need Statement

1 ACRONYMS AND ABBREVIATIONS 2 AASHTO American Association of State Highway and Transportation Officials 3 EA Environmental Assessment 4 EIS Environmental Impact Statement 5 FHWA Federal Highway Administration 6 HOV high-occupancy vehicle 7 I-15 8 I-515 Interstate 515 9 MVM million vehicle miles 10 NDOT Nevada Department of Transportation 11 PDO property damage only 12 PEL Planning and Environmental Linkages 13 US 93 U.S. Highway 93 14 US 95 U.S. Highway 95

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I-515 Downtown Access Project Draft Purpose and Need Statement TABLE OF CONTENTS

Acronyms and Abbreviations ...... iii

Why is This Project Needed?...... 1-1 1.1 Project Limits ...... 1-2 1.2 Why is the Project Needed? ...... 1-4 1.2.1 Deteriorated Bridge Condition ...... 1-4 1.2.2 Reduce Travel Delay and Traffic Congestion ...... 1-10 1.2.3 Improve Safety ...... 1-17 1.2.4 Importance of I-515 ...... 1-20 1.3 Project Background ...... 1-20 1.3.1 I-515/Charleston Boulevard Interchange Improvement Environmental Assessment ...... 1-21 1.3.2 I-515 Alternatives Development Study ...... 1-21 1.3.3 I-515 Southbound Auxiliary Lane and Viaduct Rehabilitation Project 1-23 1.3.4 Downtown Access Project Builds off Previous Studies ...... 1-24 1.4 Public, Local Government, and Agency Input on Need for the Project . 1-24 1.5 Purpose of the Project ...... 1-24 1.6 References ...... 1-25

Figures Figure 1-1a. Project Vicinity ...... 1-3 Figure 1-1b. Project Limits ...... 1-5 Figure 1-2. Viaduct Deterioration ...... 1-7 Figure 1-3a. Morning Rush-Hour Average Speeds ...... 1-11 Figure 1-3b. Evening Rush-Hour Average Speeds ...... 1-12 Figure 1-4. Average Speeds on I-515 South ...... 1-13 Figure 1-5. Average Speeds on I-515 North ...... 1-13 Figure 1-6. I-515 North Closely Spaced Ramps in Downtown ...... 1-15 Figure 1-7. Locations of Traffic Issues ...... 1-16 Figure 1-8. Summary of Study Area Crashes on I-515 and Interchanges, July 2011 to July 2014 ...... 1-17 Figure 1-9. I-515 Corridor Crashes by Roadway Segment, July 2011 to July 2014 ...... 1-19 Figure 1-10. I-515 Corridor Crash Rates per Million Vehicle Miles (MVM) by Roadway Segment, July 2011 to July 2014...... 1-19 Figure 1-11. Studies in the Project Vicinity ...... 1-22

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I-515 Downtown Access Project Draft Purpose and Need Statement

1 CHAPTER 1

2 WHY IS THIS PROJECT NEEDED?

3 The Nevada Department of Transportation (NDOT) and the Federal Highway Administration 4 (FHWA) are studying alternatives to address structural issues on the Las Vegas Viaduct, reduce 5 congestion, and improve safety on the 3.5 miles of Interstate 5151 (I-515) between Rancho 6 Drive on the west and Mojave Road on the east in Las Vegas, Nevada. A key deficiency is the 7 condition of the 1.6-mile-long Las Vegas Viaduct that carries I-515 over the Union Pacific 8 Railroad and several local streets and parking lots. This project is referred to as the Downtown 9 Access Project.

What is a Viaduct? A viaduct is a type of bridge with several spans of almost the same length. Viaducts typically connect two points with similar heights. They are built to cross railroads, multiple cross-streets, or both. Part of the Las Vegas Viaduct is shown below.

1 U.S. Highway (US) 93 and US 95 are also routed along this segment of freeway. While they are important routes, this document will refer to Interstate 515 (I-515) rather than I-515/US 93/US 95.

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-1 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 Chapter Summary 2 This chapter has the following major sections: 3 • 1.1 Project Limits 4 - Explanation of where the project is 5 • 1.2 Why is the Project Needed? 6 - Deteriorated condition of the Las Vegas Viaduct 7 - Reducing travel delay and congestion 8 - Improving safety 9 - Importance of I-515 to the and beyond 10 • 1.3 Project Background 11 - Explanation of how this project relates to recent NDOT studies of I-515 12 • 1.4 Public, Local Government, and Agency Input on Need for the Project 13 - A brief summary of meetings held with local government, organizations, and the 14 public [to be completed in 2020] 15 • 1.5 Purpose of the Project 16 This chapter summarizes detailed technical information regarding bridge 17 conditions, traffic operations, traffic forecasts, and safety.

18 1.1 Project Limits 19 I-515 extends 14 miles between the Las Vegas Which way is north? 20 “Spaghetti Bowl” interchange at I-15 and the I-215 Drivers on I-515 see signs for 21 interchange in Henderson, with several interchanges I-515 North and I-515 South 22 serving both cities and unincorporated areas of Clark because I-515 is generally a 23 County (Figure 1-1a). At its northwest end, I-515 north-south freeway. However, in the project area for the 24 provides access to and I-15. At Downtown Access Project, I-515 25 its southeast end, I-515 connects to the Las Vegas lies in more of an east-west 26 Beltway (I-215) and I-11 in Henderson. direction. “Southbound” vehicles (on I-515 South) are headed east 27 The Downtown Access Project is between the toward Henderson, and 28 recently completed Project NEON to the west, which “northbound” vehicles (on I-515 29 reconstructed I-15 and several of the ramps North) are headed west toward 30 connecting I-15 to I-515 the Las Vegas Spaghetti Bowl. 31 (http://ndotprojectneon.com/), and planned 32 improvements to I-515 from Eastern Avenue to Charleston Boulevard to the east, which are 33 scheduled to be built in 2022 (https://www.nevadadot.com/projects-programs/programs- 34 studies/i-515-charleston-boulevard-interchange-environmental-assessment).

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1 Figure 1-1a. Project Vicinity

2

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-3 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 The Downtown Access Project’s western limit is Rancho Drive, west of I-15 (Figure 1-1b), 2 because there is traffic congestion on I-515/U.S. Highway 95 (US 95) through the Spaghetti 3 Bowl that this study will address. The project’s east limit is Mojave Road a few blocks east of 4 Eastern Avenue. The north and south limits are far enough to include I-515 connections to local 5 streets and tie back into I-15, but the recently 6 completed Project NEON improvements will not be What are Functionally 7 affected. Obsolete and Structurally Deficient Bridges? 8 1.2 Why is the Project Needed? Bridges that cannot reliably support the load of vehicles may 9 1.2.1 Deteriorated Bridge Condition be considered structurally 10 The Las Vegas Viaduct is approximately 1.6 miles long, deficient. Bridges with not enough 11 from 21st Street (west of Eastern Avenue) to Mesquite room for full shoulders and/or full- width lanes or not enough 12 Avenue west of the Union Pacific Railroad tracks, and clearance over the road below 13 made up of two multispan bridges that connect just the bridge, are deemed 14 east of 4th Street. There is a full interchange at Las functionally obsolete. If the road 15 Vegas Boulevard, an on-ramp to westbound I-515 from below the bridge is too narrow 16 4th Street, and an off-ramp from eastbound I-515 to because of the narrow spacing of the bridge’s columns, that could 17 Casino Center Boulevard. The Las Vegas Viaduct is be another factor in identifying 18 functionally obsolete, and its structural integrity is the bridge as functionally 19 degrading due to age. Just east of the Las Vegas obsolete. 20 Viaduct, the bridge carrying I-515 over Eastern Avenue 21 is structurally deficient. The functional and structural condition of the Las Vegas Viaduct and 22 bridge over Eastern Avenue is a primary factor in NDOT’s decision to perform the Downtown 23 Access Project.

24 West Viaduct 25 NDOT built the west viaduct, which extends about 0.4 mile between 4th Street and Mesquite 26 Avenue, in the late 1960s with a planned service life of 50 years. The west viaduct is at the end 27 of its planned service life and is in poor overall condition. 28 NDOT surveyed some elements of the west viaduct in 2018, as documented in the Inspection 29 Report for Bridge G-947 (NDOT 2018a). The survey identified several areas that are 30 experiencing extensive concrete cracking, spalling (e.g., breaking, flaking, or pitting), expansion 31 joint failure, and water intrusion. In some places where concrete has fallen away, it has exposed 32 the steel reinforcing bars, which then began to corrode (Figure 1-2).

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1 Figure 1-1b. Project Limits

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I-515 Downtown Access Project Draft Purpose and Need Statement

1 Figure 1-2. Viaduct Deterioration

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I-515 Downtown Access Project Draft Purpose and Need Statement 1 Additionally, the columns that hold up the viaduct are 2 seismically deficient because the viaduct was not built What is Seismically 3 to meet current seismic performance requirements. Deficient? 4 The report also indicates that the vehicle load level The west viaduct is seismically 5 that can be carried is below an established FHWA deficient because the reinforcing steel in its columns was not 6 threshold, and the west viaduct’s ability to carry designed to prevent the viaduct 7 oversized loads is reduced. from collapsing during a large- 8 Although the west viaduct is in poor overall condition, scale earthquake. The vertical reinforcing steel in the bridge 9 NDOT does not classify the west viaduct and its columns is not adequately 10 interchange ramps as structurally deficient. However, anchored into the underground 11 one bridge carrying the I-515 South off-ramp to Casino base of the columns, and the 12 Center Boulevard is classified as functionally obsolete horizontal reinforcing steel ties in the columns are too widely 13 because the bridge deck is not wide enough to meet spaced to prevent damage during 14 NDOT standards for traffic lane and shoulder width. In an earthquake. 15 addition, the west viaduct’s seismic risk rating is over 16 twice as high as NDOT’s action threshold value. The 17 west viaduct would require costly retrofitting measures to comply with current seismic design 18 standards in the short term. NDOT estimated that about 100 west viaduct columns would have 19 to be wrapped with steel column casings to meet NDOT’s current seismic standards. Some of 20 the columns that would have to be wrapped extend over 9 feet below ground. 21 The need to rehabilitate or replace a bridge is based on its existing structural condition (such as 22 load-carrying capacity) and functional condition (such as width of the bridge and clearance 23 underneath the bridge). NDOT constructed the Las Vegas Viaduct and other bridges in the study 24 area to have a 50-year service life. The 50-year service life can be extended through 25 rehabilitation, but the cost of rehabilitation eventually approaches the cost of completely 26 replacing the bridge. 27 NDOT is currently planning to spend approximately $30 million on short-term improvements to 28 the viaduct in 2021 (see Section 1.3.3) to ensure it is safe until the entire viaduct can be 29 replaced. NDOT does not usually schedule extensive rehabilitation projects like this when there 30 is a plan to make extensive repairs or replace a bridge in a few years, but in this case, the short- 31 term rehabilitation is needed to preserve the Las Vegas Viaduct until the more extensive repairs 32 or replacement take place as part of the Downtown Access Project in approximately 2027. 33 Because of the 6-year lag between the short-term rehabilitation and the long-term repair or 34 replacement, there will be little or no “throwaway” cost. NDOT typically wants 5 years of useful 35 life from short-term rehabilitation before a long-term solution is implemented. In this case, 36 there will be at least 6 years between the short-term rehabilitation and the long-term solution.

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-9 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 East Viaduct 2 NDOT completed the 1.2-mile-long east viaduct in 1985. NDOT considers the east viaduct and 3 associated interchange ramps to be in a relatively good state of repair based on the results of 4 its 2017 bridge inspections. However, the travel lanes in the one-half mile segment of the east 5 viaduct between 21st Street and Maryland Parkway have a series of peaks and valleys, resulting 6 in a poor-quality “roller coaster” ride for users. The latest NDOT bridge inspection report (NDOT 7 2017a) documents minor repairs needed in the short term, with more significant longer-term 8 repairs recommended if funding is available. The east viaduct is not classified as structurally 9 deficient nor is it considered functionally obsolete. 10 As expected for a 35-year-old bridge, various elements of the east viaduct are reaching the 11 point where major maintenance/minor rehabilitation is needed to repair existing deficiencies 12 and ensure its longevity. In addition, NDOT’s assessment of the east viaduct’s seismic 13 performance identified the need for retrofitting a portion of the columns that hold up the 14 viaduct.

15 Bridge Over Eastern Avenue 16 The I-515 bridge over Eastern Avenue is structurally deficient. Its superstructure is rated as a 4 17 in its most recent inspection. A 4 rating (out of 10) is defined by FHWA as poor condition. The 18 overall sufficiency rating is 58 out of 100, the lowest of any bridge in the study area. In 19 September 2019, NDOT received a grant from FHWA to replace this bridge. NDOT will replace it 20 in the 2023-2025 timeframe, before the Downtown Access Project is built. The grant allows 21 NDOT to design the replacement bridge to match the plan for the Downtown Access Project 22 developed as part of this study. 23 In the study area, the vertical clearance under several bridges is less than NDOT’s standard of 24 16.5 feet for new construction. However, the vertical clearance under all study area bridges 25 exceeds the minimum threshold for existing bridges over highways (15.0 feet) and for bridges 26 over local streets (14.0 feet).

27 1.2.2 Reduce Travel Delay and Traffic Congestion 28 The congestion on I-515 in the project area is caused by closely spaced ramps and high traffic 29 volumes, which drastically reduce speeds and increase delays (Figures 1-3a and 1-3b). In 2009, 30 the traffic volume on I-515 in the project area was approximately 155,000 vehicles per day. 31 Based on 2019 traffic counts, traffic volumes have increased 17 percent to approximately 32 182,000 vehicles per day. Congestion is highest on I-515 North in both the morning rush hour 33 and evening rush hour. 34 One way of measuring congestion on a highway segment is the average speed. Figures 1-4 and 35 1-5 illustrate existing average speeds on the various segments of I-515 South and North. In 36 several segments, average speed is below 35 miles per hour, and as low as 18 miles per hour, 37 while the posted speed limit is 65 miles per hour.

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1 Figure 1-3a. Morning Rush-Hour Average Speeds

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1 Figure 1-3b. Evening Rush-Hour Average Speeds

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1 Figure 1-4. Average Speeds on I-515 South 2 Speeds

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4 Figure 1-5. Average Speeds on I-515 North 5 Speeds

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MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-13 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 Another way of measuring congestion on a highway segment is the increase in travel time. 2 Based on recent traffic data, it takes an additional one minute and 16 seconds to travel through 3 the study area during morning rush hour and an additional 2 minutes and 19 seconds to travel 4 through the study area during evening rush hour compared to the time it would take without 5 congestion. 6 Recently, NDOT studied traffic congestion on the entire Las Vegas freeway system. The 7 Southern Nevada Traffic Study (NDOT 2018b) noted that merging and weaving traffic and the 8 lane drop on I-515 near I-15 all contribute to high levels of congestion on I-515.

9 Interchange and Ramp Spacing 10 There are two spacing distances that are critical to providing safe and efficient access to the 11 study area freeway system: interchange spacing and ramp spacing (see the graphic below for 12 definitions). According to American Association of State Highway and Transportation Officials 13 (AASHTO) guidelines (2011), minimum interchange spacing is 1 mile and on-ramp and off-ramp 14 spacing is 1,600 feet in urban areas. 15 Interchange Spacing and Ramp Spacing

16

17 Interchanges in the study area were built close together to serve dense local development; the 18 interchanges at , Casino Center Boulevard, and I-15 are spaced less than 1 19 mile apart. On I-515 North, the Las Vegas Boulevard entrance ramp is too close to the Casino 20 Center Boulevard entrance ramp, and both are too close to the exit ramp to I-15 South (see

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-14 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 Figure 1-6). The space between the Casino Center Boulevard entrance and the exit to I-15 South 2 is only 500 feet. Similarly, on I-515 South, the entrance from I-15 is closer than it should be to 3 the Casino Center Boulevard interchange, which in turn is too close to the Las Vegas Boulevard 4 interchange. 5 When vehicles enter or exit the freeway at closely spaced ramps, they must cross paths with 6 other vehicles. Crossing two or more lanes traveling in the same direction is referred to as 7 “weaving.” In general, speeds decrease and congestion increases as the weave segment 8 shortens. Figure 1-6 shows an example in the study area. 9 Closely spaced on- and off-ramps also create bottlenecks when merging traffic attempts to 10 enter a freeway and vehicles in the right freeway lane are either unable to move left because of 11 traffic volume or are reluctant to move left because they will exit at the next off-ramp. As the 12 freeway and ramp volumes increase, the problem is exacerbated, leading to congestion and an 13 increased risk of crashes. Closely spaced interchanges and ramps contribute to the congestion 14 and high crash rates on I-515. 15 Figure 1-6. I-515 North Closely Spaced Ramps in Downtown Las Vegas

16 17 Backups at On- and Off-ramps 18 Poor operations on local streets at ramp termini can cause backups on the exit ramps, and poor 19 freeway operations can cause congestion on entrance ramps and local streets. At Casino Center 20 Boulevard and Las Vegas Boulevard, traffic backed up on the I-515 on-ramps sometimes spills 21 back onto these streets, causing congestion and increasing the potential for crashes. At Eastern 22 Avenue, the backups on the off-ramp sometimes cause backups onto I-515. It is unsafe for one 23 freeway lane to be stopped or at low speeds while traffic in the adjacent lane is moving much 24 faster. 25 Figure 1-7 illustrates the locations of the traffic issues described above.

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1 Figure 1-7. Locations of Traffic Issues

2 3 Source: NDOT 2017b

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1 1.2.3 Improve Safety 2 (This discussion will be updated in 2020 when updated crash data are available.) Roadway 3 safety is measured by the frequency and severity of crashes over a 3-year period. The annual 4 rate of crashes is compared to other similar roadways statewide. An important objective of any 5 transportation improvement is to minimize overall crash potential, and Nevada has a Zero 6 Fatality goal focused on eliminating all fatalities and serious injuries on public roadways. 7 Reducing the overall crash potential of a roadway or intersection also reduces congestion. 8 The crash analysis for this Environmental Impact Statement (EIS) used data from the Road 9 Safety Assessment Report for I-515/US 93/US 95 from Rancho Drive to Wyoming Avenue Grade 10 Separation (NDOT 2015) for the period July 2011 to July 2014 and includes crashes along I-515 11 and at on- and off-ramp intersections with crossroads. NDOT is in the process of preparing an 12 updated crash analysis using 2016-2018 crash data. That information will be added to a future 13 version of this document.

NDOT’s mission is to continually improve the safety of Nevada’s highways and freeways for the users of these systems. Traffic safety engineering goals are to implement safety features and enhancements that decrease the frequency, rate, severity of, and potential for crashes involving motor vehicles, pedestrians, bicycles, and wildlife on state- maintained roadways in Nevada.

14 For the 3-year period (2011 to 2014), a total of 865 crashes occurred in the 3.5 miles of I-515 15 from Eastern Avenue to Rancho Drive. Of these, 596 were property damage only (PDO) crashes, 16 and 269 were injury crashes, resulting in 417 injuries (Figure 1-8). No fatal crashes were 17 recorded. The crash rate was higher than NDOT statewide crash rates for roadways of similar 18 classification. Figures 1-9 and 1-10 show that the I-515 corridor experiences higher overall 19 crashes, injury crashes, and PDO crashes than the state average. 20 Rear-end crashes are the most common crash type within the corridor. This is a common crash 21 type on congested roadways where vehicles must accelerate and decelerate over short 22 distances. The high number of rear-end crashes may also be due to higher-speed free-flow 23 traffic in the through lanes adjacent to slow and stopped traffic. 24

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1 Figure 1-8. Summary of Study Area Crashes on I-515 and Interchanges, July 2011 to July 2014

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1 Figure 1-9. I-515 Corridor Crashes by Roadway Segment, July 2011 to July 2014

2 3 Source: NDOT 2017b 4 Figure 1-10. I-515 Corridor Crash Rates per Million Vehicle Miles (MVM) by 5 Roadway Segment, July 2011 to July 2014

6 7 Source: NDOT 2017b

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-19 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 Figure 1-8 also illustrates the number of crashes along the I-515 corridor by time of day and 2 crash severity. The figure shows an increase in all crash types from 7:00 AM to 9:00 AM, and 3 from 2:00 PM to 7:00 PM. These time periods coincide with the I-515 morning and evening 4 peak traffic periods. 5 Crashes at I-515 interchanges within the traffic study area for the 3-year analysis period are 6 summarized below. 7 • I-515/Eastern Avenue Interchange: Ninety-four crashes occurred at the interchange on- 8 and off-ramps, including 62 PDO crashes and 32 injury crashes, resulting in 42 injuries. 9 Rear-end crashes accounted for 67 percent of the total crashes. 10 • I-515/Las Vegas Boulevard Interchange: Seventy-one crashes occurred at the 11 interchange on- and off-ramps, including 50 PDO crashes and 21 injury crashes, resulting 12 in 30 injuries. Rear-end crashes accounted for 77 percent of the total crashes. 13 • I-515/Casino Center Boulevard Interchange: Fifteen crashes occurred at the interchange 14 on- and off-ramps, including 13 PDO crashes and 2 injury crashes, resulting in 2 injuries. 15 Rear-end crashes accounted for 40 percent of the total crashes.

16 1.2.4 Importance of I-515 17 I-515 provides important local connections within the city of Las Vegas and regional 18 connections between Las Vegas, Henderson, and Boulder City. Its importance will be enhanced 19 if it becomes part of a larger interstate network linking Las Vegas and Phoenix. NDOT and the 20 Arizona Department of Transportation are currently evaluating corridors to link the two cities, 21 including the I-515 corridor. Congress established the I-11 corridor in 2012, and FHWA 22 approved the establishment of I-11 from the Arizona state line to I-215 on May 29, 2014. NDOT 23 has already installed signs designating US 93 as I-11 from the Mike O'Callaghan - Pat Tillman 24 Memorial Bridge at Hoover Dam to the I-515/I-215 interchange in Henderson (Interstate Guide 25 2019). 26 I-515 is recommended for high-occupancy vehicle (HOV) lanes in the future, under NDOT’s 27 Southern Nevada High Occupancy Vehicle Plan Addendum (NDOT 2018d). The plan 28 recommends one HOV lane in each direction on I-515 as part of region-wide HOV lane system. 29 NDOT will consider HOV interchanges at Maryland Parkway and City Parkway, both of which are 30 in the Downtown Access Project study area. The safety, structural condition, and traffic 31 congestion issues described earlier would not allow I-515 in its current layout to accommodate 32 the HOV recommendations from the plan.

33 1.3 Project Background 34 The high traffic volumes on I-515 between the Spaghetti Bowl and Charleston Boulevard, 35 coupled with bottlenecks caused by insufficient interchange and ramp spacing, contribute to 36 impaired traffic flow and a higher-than-expected number of crashes. As a result, NDOT began a 37 series of studies along I-515 from the Spaghetti Bowl to Charleston Boulevard to identify and

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-20 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 evaluate operational and safety improvements that could be implemented by NDOT in 2 coordination with future capacity improvements along I-515. The most comprehensive of 3 NDOT’s studies in the I-515 corridor was the I-515 Alternatives Development Study Concept 4 Report (NDOT 2017b). The concepts developed in that study were incorporated in the projects 5 described below. 6 The I-515 studies between the Spaghetti Bowl and Charleston Boulevard and the projects 7 identified within them are summarized below. Figure 1-11 provides an overview of the short- 8 and long-term projects within and immediately adjacent to this Downtown Access Project to 9 assist the reader in understanding the relationship among several studies and projects that 10 NDOT is planning in the segment of I-515 between Charleston Boulevard and the Spaghetti 11 Bowl.

12 1.3.1 I-515/Charleston Boulevard Interchange Improvement Environmental 13 Assessment 14 In 2016, NDOT and FHWA formally began the I-515/Charleston Boulevard Interchange 15 Environmental Assessment (EA) following a City of Las Vegas study (City of Las Vegas 2015) that 16 evaluated alternatives to improve traffic operations along Charleston Boulevard and the I- 17 515/Charleston Boulevard ramps. The I-515/Charleston Boulevard Interchange EA study limits 18 along I-515 extended from the east half of the Eastern Avenue interchange to Wyoming 19 Avenue. The purpose of the project was to reduce crashes, congestion, and travel delays by 20 improving the movement of traffic on Charleston Boulevard and I-515 (FHWA and NDOT 2019). 21 Several components of the I-515/Charleston Boulevard Interchange EA originated from the 22 I-515 Alternatives Development Study. The EA for the I-515/Charleston Boulevard Interchange 23 was approved by FHWA and NDOT in May 2019, with the final environmental approval in 24 September 2019. NDOT has programmed construction to begin in 2022.

25 1.3.2 I-515 Alternatives Development Study 26 NDOT began the I-515 Alternatives Development Study in 2015 to develop and evaluate short- 27 and long-term alternatives to reduce congestion and traffic delays and improve safety between 28 the Spaghetti Bowl and Charleston Boulevard. 29 In 2016, the I-515 Alternatives Development Study developed and began screening 35 30 conceptual improvements in a four-step screening process.

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1 Figure 1-11. Studies in the Project Vicinity

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1 Ultimately, NDOT decided to pursue six projects from the concepts that survived the screening 2 process. A brief description of projects is found in Table 3-3 of the I-515 Alternatives 3 Development Study Concept Report (NDOT 2017b), and their status is as follows: 4 1. City Parkway Exit Ramp – The proposed ramp to City Parkway from the 5 US 95/northbound I-15 ramp did not satisfy 2017 FHWA access criteria and the change 6 in interstate access was denied by FHWA. 7 2. Las Vegas Boulevard and Casino Center Boulevard Interchange Improvements – This 8 project will be considered in coordination with potential capacity improvements along 9 this section of I-515. 10 3. Eastern Avenue Interchange Improvements – This project will be considered in 11 coordination with potential capacity improvements along this section of I-515. 12 4. I-515 South Auxiliary Lane between I-15 and Charleston Boulevard – NDOT advanced 13 this project and plans to build it in 2021-2022. 14 5. Pecos Road Interchange – This project will be considered in coordination with potential 15 capacity improvements along this section of I-515. Pecos Road is between Eastern 16 Avenue and Charleston Boulevard, outside the limits of this project. 17 6. Braided Ramps/Collector-Distributor Road Between Las Vegas Boulevard and I-15 – 18 This project will be considered in coordination with potential capacity improvements 19 along this section of I-515. 20 In June 2017, NDOT produced the I-515 Alternatives Development Study Concept Report (NDOT 21 2017b) documenting the transportation deficiencies along I-515, the alternatives development 22 and refinement process that led to the six projects described above, and the natural resource 23 and socioeconomic impacts of the six projects. The I-515 Alternatives Development Study 24 Concept Report can be found at https://www.nevadadot.com/home/showdocument?id=16753. 25 Chapter 2 of the report describes existing conditions in the I-515 study corridor, and Chapter 3 26 describes the development and screening of the 35 alternative concepts and the six projects.

27 NDOT used FHWA’s Planning and Environmental Linkages (PEL) approach (FHWA 2019) in 28 conducting the I-515 Alternatives Development Study. A PEL study is a collaborative approach 29 to transportation decision-making that considers environmental, community, and economic 30 goals early in the transportation planning process to inform the subsequent environmental 31 review and reduce the time required to gain approval of National Environmental Policy Act 32 documents such as this Draft EIS. More information about the PEL approach can be found at 33 https://www.environment.fhwa.dot.gov/env_initiatives/PEL.aspx.

34 1.3.3 I-515 Southbound Auxiliary Lane and Viaduct Rehabilitation Project 35 In 2018, NDOT combined the I-515 Southbound Auxiliary Lane Project (Project 4 above) with a 36 short-term viaduct rehabilitation project and advanced it to final design. As part of the project,

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-23 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement 1 NDOT will spend approximately $30 million to improve the driving surface of the Las Vegas 2 Viaduct by adding an asphalt overlay and performing other short-term rehabilitation work, such 3 as: 4 • Replacing a hinge seat on the segment that carries the exit ramp to Casino Center 5 Boulevard. 6 • Replacing worn-out expansion joints, repairing cracks and spalling, and repairing the 7 deck. 8 • Performing a partial seismic retrofit of the Las Vegas Viaduct between 21st Street and 4th 9 Street. NDOT will wrap the columns on the east viaduct in steel casing but will not wrap 10 the 100+ columns holding up the west viaduct. 11 • Adding an auxiliary lane on I-515 South between I‐15 and Eastern Avenue. NDOT will 12 reduce lane and shoulder widths to 11 feet to accommodate the auxiliary lane without 13 widening the viaduct and acquiring new right-of-way. 14 NDOT is planning to construct the short-term improvements in 2021.

15 1.3.4 Downtown Access Project Builds off Previous Studies 16 In summer 2019, NDOT began this Downtown Access Project to address the deteriorating Las 17 Vegas Viaduct, improve traffic operations, and reduce crashes on I-515 between the Eastern 18 Avenue interchange and Rancho Drive. While the I-515 Alternatives Development Study Concept 19 Report discusses the existing condition of the Las Vegas Viaduct (NDOT 2017b; Chapter 2) and 20 provides recommendations for required long-term improvements to the viaduct, the 21 Downtown Access Project is not one of the six projects evaluated in detail in the report. It 22 should be noted, however, that NDOT and FHWA will use to the extent practicable the 23 environmental impact analysis and engineering work conducted for projects 2, 3, and 6, which 24 are located between Eastern Avenue and the Spaghetti Bowl. These projects and associated 25 concepts are shown on Figure 3-6 of the I-515 Alternatives Development Study Concept Report.

26 1.4 Public, Local Government, and Agency Input on Need for the 27 Project 28 (To be completed) 29 • Summarize public input from a planned summer 2020 public meeting. 30 • Summarize City of Las Vegas input from various meetings. 31 • Summarize input from state and federal resource agencies, in response to initial scoping.

32 1.5 Purpose of the Project 33 The purpose of the project is to: 34 • Improve the poor condition of the Las Vegas Viaduct;

MAY 2020 CHAPTER 1: WHY IS THE PROJECT NEEDED? 1-24 DRAFT – WORK IN PROGRESS I-515 Downtown Access Project Draft Purpose and Need Statement

1 • Improve poor traffic operations that are currently caused by high traffic volumes; and 2 • Reduce crash rates that are currently higher than other urban freeways in Nevada. 3 The project purpose and need set the stage for NDOT and FHWA to develop and evaluate 4 alternatives to address these issues. NDOT and FHWA will evaluate the alternatives based on 5 how well each alternative addresses the project’s purpose and need. Additional factors to be 6 considered in the evaluation are input from resource agencies, local governments, tribes, and 7 the public, as well as project costs and impacts to the human and built environments.

8 1.6 References 9 American Association of State Highway and Transportation Officials (AASHTO). 2011. A Policy on 10 Geometric Design of Highways and Streets (Green Book). 11 City of Las Vegas. 2015. City of Las Vegas I-515 and Charleston Boulevard Interchange 12 Alternatives Feasibility Study. 13 Federal Highway Administration (FHWA). 2019. Environmental Review Toolkit: FHWA Initiatives 14 to Accelerate Project Delivery - Planning and Environment Linkages (PEL). 15 https://www.environment.fhwa.dot.gov/env_initiatives/PEL.aspx. 16 Federal Highway Administration (FHWA) and Nevada Department of Transportation (NDOT). 17 2019. I-515/Charleston Boulevard Interchange Environmental Assessment. 18 https://www.nevadadot.com/home/showdocument?id=16657. May. 19 Interstate Guide. 2019. Interstate 515 Nevada. http://www.interstate-guide.com/i-515-nv/. 20 Nevada Department of Transportation (NDOT). 2015. Road Safety Assessment Report for I- 21 515/US 93/US 95 from Rancho Drive to Wyoming Avenue Grade Separation. 22 Nevada Department of Transportation (NDOT). 2017a. Inspection Report for Bridge I-947. 23 October 30. 24 Nevada Department of Transportation (NDOT). 2017b. I-515 Alternatives Development Study 25 Concept Report. https://www.nevadadot.com/home/showdocument?id=16753. June. 26 Nevada Department of Transportation (NDOT). 2018a. Inspection Report for Bridge G-947. 27 November 29. 28 Nevada Department of Transportation (NDOT). 2018b. Southern Nevada Traffic Study Final 29 Report. http://www.ndotsnts.com/assets/SNTS_Final_Report_Interactive.pdf. November. 30 Nevada Department of Transportation (NDOT). 2018d. Southern Nevada High Occupancy 31 Vehicle Plan Addendum. https://www.nevadadot.com/safety/roadway-safety- 32 improvements/high-occupancy-vehicle-hov-lanes-express-lanes.

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