! " # $% &! October 08, 2008 Mr. Dean Papajohn, PE Civil Engineering Manager Pima County Department of Transportation Public Works Building 201 N. Stone Avenue, 4th Floor Tucson, AZ 85701-1207 RE: Final Design Concept Report La Cholla Boulevard Ruthrauff to River Road Project No. 4LCITR HDR Job No. 59914 Dear Mr. Papajohn: We are pleased to submit the Final Design Concept Report for the above-referenced project. This report was prepared by Robert Brittain, PE and was reviewed by Ted Buell, PE. Sincerely, HDR Engineering, Inc. Ted W. Buell, PE Project Manager Attachments Prepared for: Pima County Department of Transportation 201 N. Stone Avenue Tucson, AZ 85701 Project No. 4LCITR Prepared by: HDR Engineering, Inc. 5210 E. Williams Circle, Suite 530 Tucson, AZ 85711-4459 HDR Project No. 59914 APPROVED: __________________________________ Pima County Director of Transportation __________ Date La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Executive Summary This project involves the reconstruction of La Cholla Boulevard from Ruthrauff Road to River Road from a two-lane roadway into a six-lane arterial street. The entire project is located in unincorporated Pima County. Location and vicinity maps are included as Figures 1 and 2. On May 16, 2006, the citizens of Pima County approved a $2.1 billion transportation plan to be funded by a one-half cent increase in the sales tax. Current project funding includes $14,760,000 from this sales tax revenue. Other funding includes $3,691,000 in Highway User Revenue Fund (HURF) revenue and $1,549,000 in Pima County Impact Fees for total funding of $20 million. It is estimated that this project will be advertised for bids in the spring of 2010. Construction is anticipated to be complete in late 2011. This section of La Cholla Boulevard is slated to be a major arterial roadway in the Pima Association of Governments Metropolitan Transportation Plan. The widening is needed to accommodate the heavy volumes of traffic projected in the year 2030. There are also vertical deficiencies in the existing roadway profile which limit stopping sight distances. Constructing this new arterial roadway to current standards will increase traffic capacity and user safety in all weather conditions. The design speed for this project is 50 mph. It will be posted at 45 mph. The existing right-ofway width of 150 feet will be sufficient for the six-lane roadway. Landscaping will be provided in the median and parkway areas. Artwork will also be included with this project. Drainage improvements will include a new six-lane bridge over the Rillito River, and a storm drain system consisting of catch basins and pipe culverts capable of conveying a 50-year storm. No box culverts and only minimal channel work are anticipated. Driveways will be provided to every property that currently has access to La Cholla Boulevard. Median openings will be provided at all side streets except Noreen Street which is too close to Ruthrauff Road to have an opening. Existing traffic signals will be modified at the intersections of River Road, Curtis Road and Ruthrauff Road. No new traffic signals will be added. An alignment alternatives study was performed to determine how to handle access to the single family homes located at the southern end of the project. The following six main alignment alternatives were considered: Alternative A This alternative involves shifting the La Cholla Boulevard centerline to the east about 40 feet. This provides enough room to build a frontage road to serve the homes on the west side. It would require the purchase of 13 lots on the east side along with some partial takes from other properties. Alternative B This alternative involves shifting the La Cholla Boulevard centerline to the west about 40 feet. This provides enough room to build a frontage road to serve the homes on the east side. It would require the purchase of 12 lots on the west side including a City well site along with some partial takes from other properties. i La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Alternative C This alternative involves maintaining La Cholla Boulevard centered on the section line. The new road would include an additional pullout lane outside of the bike lane to provide space for the homeowners to back out a car without entering the La Cholla Boulevard travel lanes. This alternative was dropped for safety concerns. Alternative D This alternative involves maintaining La Cholla Boulevard centered on the section line similar to Alternative C, however, no pullout lanes nor frontage roads would be used to provide space for the homeowners to back out a car. Therefore, the fronting residences on both sides of La Cholla Boulevard would need to be acquired. However, no other right of way would be needed. Alternative E This alternative was created to provide an option in which right-of-way was not required from either side of La Cholla Boulevard. It involves maintaining La Cholla Boulevard centered on the section line. The median, travel and bike lanes are reduced in width. One-way frontage roads are used on both sides of La Cholla Boulevard. While no right-of-way must be purchased from the fronting residences, it will be necessary to acquire temporary construction easements to build the small slopes and reconstruct the driveways. Alternative F This alternative also maintains La Cholla Boulevard centered on the section line with the same typical section as Alternative D. However, instead of purchasing all of the homes on both sides, only eight properties would be bought. These purchased properties would be used to build circular driveways for access to the remaining homes. Variations on Alternative E Several variations on Alternative E were also considered and rejected. These variations included the following: • Replacing the median with a continuous two-way, left-turn lane. • Replacing the frontage roads with direct driveways. • Providing additional openings in the frontage road medians along with left turn bays in the main median. • Widening the frontage roads from 16 feet to 20 feet so they could function as two-way. The median would then be reduced from 18 feet to 10 feet. • Reducing the separating medians from four feet to two feet, increasing the frontage road widths to 18 feet and making them two-way. Each of these variations had safety or budgetary problems that made them unworkable. Based on the design requirements, public input and financial constraints, PCDOT recommends Alternative E. ii La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Table of Contents 1.0 Project Overview ................................................................................................................ 1 1.1 Project Location.......................................................................................................... 1 1.2 Authorization.............................................................................................................. 1 1.3 Previous Work ............................................................................................................ 1 1.4 Project Need ............................................................................................................... 1 2.0 Project Description.............................................................................................................. 4 2.1 Project Type and Termini........................................................................................... 4 2.2 Major Features............................................................................................................ 4 3.0 Project Area Characteristics................................................................................................ 8 3.1 Existing Topography and Terrain............................................................................... 8 3.2 Existing Roadway....................................................................................................... 8 3.3 Existing Rights-of-Way.............................................................................................. 8 3.4 Existing Drainage ....................................................................................................... 9 3.5 Existing Utilities, Signals, and Lighting................................................................... 10 3.6 Existing Biology....................................................................................................... 10 3.7 Archaeological and Historic Resources.................................................................... 10 3.8 Existing Visual Resources........................................................................................ 11 3.9 Existing and Future Land Use .................................................................................. 11 3.10 Intergovernmental Agreements ................................................................................ 11 4.0 Traffic and Accident Data................................................................................................. 13 4.1 Traffic ....................................................................................................................... 13 4.2 Accidents .................................................................................................................. 16 4.3 River Road Safety Assessment................................................................................. 16 5.0 Design Standards and Criteria .......................................................................................... 17 5.1 Geometric Standards ................................................................................................ 17 5.2 Design Standards ...................................................................................................... 17 5.3 Slope Standards ........................................................................................................ 17 5.4 Pavement Structure................................................................................................... 17 5.5 Design Speed ............................................................................................................ 17 5.6 Drainage Design ....................................................................................................... 17 5.7 Access Control.......................................................................................................... 18 5.8 Cross Section Elements ............................................................................................ 18 5.9 Roadway Geometrics................................................................................................ 19 5.10 Right-of-Way Width................................................................................................. 19 6.0 Major Design Features...................................................................................................... 20 iii La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.11 6.12 Horizontal and Vertical Alignment .......................................................................... 20 Access Control.......................................................................................................... 20 Right-of-Way............................................................................................................ 20 Drainage ................................................................................................................... 21 Earthwork Considerations ........................................................................................ 24 Intersections.............................................................................................................. 24 Utilities ..................................................................................................................... 24 Structures .................................................................................................................. 25 Pavement Design ...................................................................................................... 30 Signalization and Lighting ....................................................................................... 31 Construction Issues................................................................................................... 31 Design Exceptions .................................................................................................... 32 7.0 Social, Economic, and Environmental Considerations..................................................... 34 7.1 Biological Resources ................................................................................................ 34 7.2 Air Quality................................................................................................................ 34 7.3 Noise......................................................................................................................... 34 7.4 Hazardous Materials ................................................................................................. 35 7.5 Historical/Cultural Resources................................................................................... 35 7.6 Visual/Aesthetic Resources ...................................................................................... 35 7.7 Neighborhood Impact ............................................................................................... 35 7.8 Community Resource Impact ................................................................................... 36 8.0 Public Involvement ........................................................................................................... 37 8.1 Public Participation Plan .......................................................................................... 37 8.2 Community Advisory Committee ............................................................................ 37 8.3 Public Meetings ........................................................................................................ 39 9.0 Agency Coordination ........................................................................................................ 40 9.1 Environmental Review ............................................................................................. 40 9.2 Intergovernmental Agreements ................................................................................ 40 10.0 Alternatives ....................................................................................................................... 41 10.1 Location .................................................................................................................... 41 11.0 Conclusions and Recommendations ................................................................................. 61 12.0 Cost Estimate and Budget Considerations........................................................................ 62 13.0 References......................................................................................................................... 63 14.0 Abbreviation and Acronyms ............................................................................................. 64 iv La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report List of Figures Figure 1. Location Map.................................................................................................................. 2 Figure 2. Vicinity Map................................................................................................................... 3 Figure 3. Typical Roadway Cross-Section .................................................................................... 6 Figure 4. Typical Roadway Section with Frontage Roads ............................................................ 7 Figure 5. Land Use Map .............................................................................................................. 12 Figure 6. Existing Traffic Conditions .......................................................................................... 14 Figure 7. Future Traffic Conditions ............................................................................................. 15 Figure 8. Existing Storm Drain Capacity..................................................................................... 22 Figure 9. Proposed Storm Drain .................................................................................................. 23 Figure 10. Bridge Location Plan and Elevation........................................................................... 28 Figure 11. Typical Bridge Section ............................................................................................... 29 Figure 12. Alternative A Plan View ............................................................................................ 44 Figure 13. Alternative A Typical Section .................................................................................... 45 Figure 14. Alternative B Plan View............................................................................................. 46 Figure 15. Alternative B Typical Section .................................................................................... 47 Figure 16. Alternative C Plan View............................................................................................. 48 Figure 17. Alternative C Typical Section .................................................................................... 49 Figure 18. Alternative D Plan View ............................................................................................ 50 Figure 19. Alternative D Typical Section .................................................................................... 51 Figure 20. Alternative E Plan View............................................................................................. 52 Figure 21. Alternative E Typical Section .................................................................................... 53 Figure 22. Alternative F Plan View ............................................................................................. 54 List of Tables Table 1. Table 2. Table 3. Table 4. Table 5. Table 6. Table 7. Existing Utilities ............................................................................................................ 10 Accident Data ................................................................................................................ 16 Cross Section Elements ................................................................................................. 18 Right-of-Way Cost......................................................................................................... 55 Home Acquisition Requirements................................................................................... 57 Alternatives Matrix ........................................................................................................ 60 Project Cost.................................................................................................................... 62 List of Appendices Appendix A – Construction Cost Estimate Appendix B – Community Advisory Committee and Public Involvement Information Appendix C – Stage I (15%) Construction Plans (Bound Separately) Appendix D – Right-of-Way Requirements Plans (Bound Separately) v La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 1.0 Project Overview 1.1 Project Location This project is located along La Cholla Boulevard from Ruthrauff Road to River Road. Reconstruction of the Ruthrauff Road intersection will involve the addition of turn lanes and tapers along Ruthrauff Road and on La Cholla Boulevard south of Ruthrauff Road. The official title of this project is “La Cholla Boulevard, Ruthrauff Road to River Road”. The Project No. is 4LCITR. This project involves the reconstruction of La Cholla Boulevard from a two-lane roadway into a six-lane arterial street. The entire project is located in unincorporated Pima County. A location map is included as Figure 1 and a vicinity map is included as Figure 2. 1.2 Authorization The Pima County Board of Supervisors approved the contract for the design of this project in May, 2007. The notice to proceed was issued by the Director of the Department of Transportation on June 12, 2007. On May 16, 2006, the citizens of Pima County approved a $2.1 billion transportation plan to be funded by a one-half cent increase in the sales tax. Current project funding includes $14,760,000 from this sales tax revenue. Other funding includes $3,691,000 in Highway User Revenue Fund (HURF) revenue and $1,549,000 in Pima County Impact Fees for total funding of $20 million. 1.3 Previous Work The most recent work on this section of La Cholla Boulevard includes the construction of the current roadway grade and the bridge across the Rillito River in 1981, and the installation of a major storm drain in 1984. The section of La Cholla Boulevard from the bridge to River Road was built with the River Road to Omar Drive section completed in 2006. Since the new roadway will follow the existing alignment, a Location Report was not required. A Final Traffic Report was prepared by Kimley-Horn and submitted to PCDOT on February 20, 2008. An Environmental Screening Matrix and Memorandum were submitted on November 15, 2007. It is anticipated that the Final Environmental Assessment and Mitigation Report will be sent to the Board of Supervisors for approval in December 2008. Construction is anticipated to start within the first five years of the Regional Transportation Authority (RTA) plan, 2010 if no delays occur. 1.4 Project Need This section of La Cholla Boulevard is slated to be a major arterial roadway in the Pima Association of Governments Metropolitan Transportation Plan. The widening is needed to accommodate the heavy volumes of traffic projected in the year 2030. There are also vertical deficiencies in the existing roadway profile which limit stopping sight distances. Drainage is a concern today with several complaints concerning ponding problems in the right-of-way. The bridge over the Rillito River has been found to be deficient with regards to scour. Constructing this new arterial roadway to current standards will increase traffic capacity and user safety in all weather conditions. 1 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 1. Location Map 2 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 2. Vicinity Map 3 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 2.0 Project Description 2.1 Project Type and Termini This project involves the complete reconstruction of the road. The new roadway will have six travel lanes, a multi-use lane in each direction, a raised and landscaped median, and sidewalks from La Cholla Boulevard to the north bank of the Rillito River. Pedestrian trail improvements will be made to connect the La Cholla Boulevard sidewalks to the Rillito River trails on both the north and south banks. The project will also include replacing the existing two-lane bridge over the Rillito River with a six-lane bridge. The intersections of La Cholla Boulevard with Curtis Road and Ruthrauff Road will include additional right and left turn lanes. The total length of project is about one mile from River Road south to about 0.3 miles south of Ruthrauff Road. The improvements to Ruthrauff Road will extend about 1000 feet both east and west of La Cholla Boulevard. 2.2 Major Features The design speed for this project is 50 mph. It will be posted at 45 mph. The existing right-ofway width of 150 feet will be sufficient for the six-lane roadway. The typical roadway section is shown in Figure 3. Landscaping will be provided in the median and parkway areas. Vicki Scuri has been hired by PCDOT to design artwork as part of the improvements. An alignment alternatives study was performed to determine how to handle access to the single family homes located at the southern end of the project. This study is documented in Chapter 10 of this report. The PCDOT recommended alternative consists of a centered alignment with one-way frontage roads on both sides of the main arterial. To enable these improvements to fit within the existing 150-foot wide right-of-way, the lanes and median were narrowed as shown in Figure 4. Drainage improvements will include a new six-lane bridge over the Rillito River, and a storm drain system consisting of catch basins and pipe culverts capable of conveying a 50-year storm. No box culverts and only minimal channel work are anticipated. Existing utilities include 6” and 12” water, 8” and 10” sanitary sewer, 4” natural gas, telephone, cable TV, and overhead electric. It is anticipated that minor relocation of the underground lines will be required along with the overhead electric lines. Driveways will be provided to every property that currently has access to La Cholla Boulevard. Median openings will be provided at all side streets except Noreen Street which is too close to Ruthrauff Road to have an opening. Existing traffic signals will be modified at the intersections of River Road, Curtis Road and Ruthrauff Road. Street lighting will continue to be provided at signalized intersections only. Certain features of the project are included to comply with the Americans with Disabilities Act (ADA). These will ensure the project meets the accessibility guidelines. These include sidewalks meeting the minimum width and maximum slope criteria. Curb ramps will be provided at every intersection with a maximum slope of 12:1 and truncated dome warning strips at the bottom of each ramp. Crosswalks will have a maximum cross slope of 2%. 4 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Traffic signals will have wheelchair accessible push buttons. Pads for wheelchair lifts will be provided at each bus stop. The project will include the installation of landscape improvements in the medians and the roadway shoulders to the right-of-way limit in accordance with the Pima County Department of Transportation Landscape and Irrigation Design Guidelines and the Pima County Roadway Design Manual. The Arizona Community Tree Council’s Guide to Arizona Desert Shade Trees will be used as a resource in the selection of shade trees for placement near overhead electric power lines. Placement of landscape improvements will consider the extensive network of existing underground utilities in the project area and follow sight distance requirements. 5 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 3. Typical Roadway Cross-Section 6 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 4. Typical Roadway Section with Frontage Roads 7 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 3.0 Project Area Characteristics 3.1 Existing Topography and Terrain The existing terrain generally slopes gently to the northwest. Along La Cholla Boulevard, the road follows the existing terrain and slopes down from Ruthrauff Road to a low spot about 500 feet south of Curtis Road. From this point north, the road is built on an embankment which rises to a high point on the existing bridge over the Rillito River. The profile then falls to the intersection with River Road. The cross slope along La Cholla Boulevard is very mild with no major existing cut or fill slopes. There are shallow roadside ditches along La Cholla Boulevard for most of its length. The road widening can be accomplished using low 4:1 cut and fill slopes with no retaining walls or slope protection being anticipated. 3.2 Existing Roadway The existing roadway is uncurbed and has two twelve-foot travel lanes with four-foot paved shoulders for most of its length. The existing surface is asphaltic concrete. The roadway also has a northbound left turn lane and southbound left and right turn lanes at Ruthrauff Road. At Curtis Road there is a northbound left turn lane. The south leg of the River Road intersection was recently built out with curb & gutter and includes six travel lanes, double left turn lanes, a right turn lane, bike lanes, sidewalks and a raised median island. The existing bridge over the Rillito River is 52-feet wide with two 12-foot lanes and two 10-foot shoulders. There is also a six-foot sidewalk on the east side of the bridge. The existing horizontal alignment is straight with only one set of fairly flat (radius = 7600’) reverse curves located just south of Curtis Road. The vertical profile contains gentle grades varying from 0.19% to 1.79%. There is a 350’ sag vertical curve located south of Curtis Road and an 800’ crest vertical curve over the Rillito River. Both vertical curves meet a 55 mph design speed. The posted speed is 35 mph. 3.3 Existing Rights-of-Way La Cholla Boulevard has a 150-foot existing right-of-way with the following exceptions: • • • On the west side, the first 400 feet south of the River Road centerline has a 100-foot half right-of-way. On the east side, from River Road to Curtis Road, there is a 100-foot half of right-of-way. On the east side, the first 300 feet south of the Ruthrauff Road centerline has a 100-foot half right-of-way. Ruthrauff Road has a 150-foot existing right-of-way. 8 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 3.4 Existing Drainage The Rillito River has a drainage area of approximately 900 square miles upstream of La Cholla Boulevard. The Rillito River drains the south portion of the Santa Catalina Mountains, the eastern portion of the Rincon Mountains, as well as several hundred square miles of desert. Watershed elevations range from 2200 to 9200 feet; watershed slopes range from less than 1% to almost vertical relief in the mountains. The Rillito River, at its crossing with La Cholla Boulevard, is a 300-foot-wide ephemeral stream with lined banks. The streambed is comprised of medium to coarse sand with some gravel and cobbles. The bed is vegetated with a typical assortment of desert vegetation, including mesquite, cottonwood and other desert vegetation. The north and south banks of the existing channel are lined with soil cement. The existing bridge measures 353 feet long from abutment to abutment and is comprised of four equal spans. The bridge is 52 feet wide. Other than the Rillito River, the main offsite watershed is roughly bordered by the Rillito River on the north, an unnamed wash that runs parallel to and 1300 feet east of La Cholla Boulevard on the east, Wetmore Road on the south, and La Cholla Boulevard on the west. Storm runoff generated within the watershed generally flows to the northwest in streets, roadside swales, and existing storm drains. The watershed is developed with single family homes, mobile home parks and light commercial developments. The vegetative cover consists of natural desert shrub, even in most of the residential areas where property owners have generally elected to maintain the desert appearance of their land in lieu of lawns or formal landscaping. North of the Rillito River is a small drainage area currently being built into a commercial office center on the southeast corner of La Cholla Boulevard and River Road. The development plan shows that the runoff will be collected and conveyed to the south through the soil cement bank protection directly into the Rillito River. Before the construction of this development this area was drained under La Cholla Boulevard to the west through an existing 24” by 38” horizontally elliptical pipe. This pipe outlets into a drainage channel that flows to the west into the Rillito River. This channel is contained within a public open space & park easement and will be used to outfall the pavement drainage system built as part of this project. The entire watershed is located on the southern alluvial plain of the Santa Catalina Mountains. The area consists of gently sloping profiles with gradients of less than 1%. Pavement runoff is conveyed in roadside ditches to the north where it either enters the existing cross drainage system through catch basins (on the east side) or a pipe culvert (on the west side) which directly outfalls into the Rillito River. The ditches are typically quite shallow with minimal capacity. In 1984, a major storm drain was installed in La Cholla Boulevard from Ruthrauff Road to the Rillito River. At the outfall, the storm drain consists of twin 66-inch reinforced concrete pipes. It was determined, from a discussion with the Pima County Flood Control District, that two ponding/flooding problems exist within the project area: at Noreen Street and Calle Narciso. Both of these problems will be fixed with this project. 9 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 3.5 Existing Utilities, Signals, and Lighting The existing utilities were mapped by Inliner American. They found the following utilities and owners: Table 1. Existing Utilities Owner Utility Pima County Regional Water Reclamation Department 8", 10", and 15" sanitary sewer Tucson Water 6", 12", and 16" water and well site Pima County Parks and Recreation 3" & 6" irrigation (on bridge), Electrical for irrigation controllers (on bridge abutments) Tucson Electric Power 46 kV and 14 kV overhead electric Southwest Gas 4" high-pressure and 4" distribution gas Qwest Telephone (on bridge) Xspedius Communications Fiber optic telephone Comcast Cable television AT&T Fiber optic telephone Pima County Traffic 2” Conduit for traffic signals (on bridge) There are existing traffic signals at the intersections of River Road, Curtis Road and Ruthrauff Road. There are street lights at these intersections, but La Cholla Boulevard does not have continuous street lighting. 3.6 Existing Biology The project area is located within the Arizona Upland Subdivision of the Sonoran desert scrub biotic community. However, most of the native vegetation has been removed from the rightof-way over the years. The Rillito River is identified by the Pima County Regional Flood Control District as an important riparian resource and serves as a potential wildlife corridor through the project area. 3.7 Archaeological and Historic Resources There are two previously identified cultural resources within the project area, archaeological site AZ AA:12:18(ASM) which is also known as the Hodges site, and AZ AA:12:29(ASM) which is recorded as a prehistoric artifact scatter. A review of the County Assessor's web site indicates that there are no standing structures likely to be 50 years old or older within the project area. 10 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 3.8 Existing Visual Resources The background views along the corridor consist of the Santa Catalina Mountains to the north-northeast, the Rincon Mountains to the east, and Tucson Mountains to the west. The middle-ground views are a mixture of medium- and low-density residential development interspersed with native and non-native vegetation. The foreground views are of residences, businesses, and a wide, unpaved, roadway shoulder that is predominately void of vegetation. 3.9 Existing and Future Land Use As shown in Figure 5, the current land use along La Cholla Boulevard includes single family homes, mobile homes on individual lots as well as in mobile home parks, businesses and a linear park along the Rillito River. The businesses include gas stations, convenience stores, auto repair, auto sales, tavern, welder, and commercial offices. South of Ruthrauff Road, there is a fire station for the Northwest Fire District and south of that is Flowing Wells Junior High School. South of Curtis Road, on the west side of La Cholla Boulevard, are two large vacant parcels. At the southeast corner of River Road and La Cholla Boulevard, a commercial and medical office development is currently being built. Just north of Ruthrauff Road, on the west side of La Cholla Boulevard, a development plan for a Family Dollar Store was submitted to Pima County, but the project is on hold. South of Ruthrauff Road, on the west side, a Walmart Neighborhood Market is currently under construction. The existing zoning along La Cholla Boulevard is Multiple Use (MU) south of Curtis Road. The County and Tucson Electric Power parcels along the Rillito River are zoned Suburban Homestead (SH). The commercial office site on the east side north of the Rillito River is zoned under a Specific Plan (SP-RE1) while the gas station on the west side is zoned for Local Business (CB-1). Public lands within the corridor include the Rillito River and two additional parcels located on the south bank, west of La Cholla Boulevard. These parcels are currently being developed into a park. 3.10 Intergovernmental Agreements There are two existing Intergovernmental Agreements that affect this project. The first is between Tucson Water and Pima County which provides for a 50-50 sharing of expenses for any water lines that must be relocated due to the reconstruction of a road by Pima County. The second IGA is between the Pima County Regional Transportation Authority and Pima County. It provides for some of the funding of the design and construction of this project. 11 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 5. Land Use Map 12 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 4.0 Traffic and Accident Data 4.1 Traffic General A traffic analysis report was prepared by Kimley Horn (Reference 1) to document existing and future traffic conditions, and to provide recommendations for number and length of turning lanes at intersections, location of median openings, and the need for additional traffic signals. The current average daily traffic volumes along La Cholla Boulevard between Ruthrauff Road and River Road vary from 23,400 to 28,400. In the year 2030, the traffic volumes are expected to increase to between 41,000 and 44,000 vehicles per day. The proposed six lane roadway section will satisfactorily handle these quantities of traffic with Level of Service B. Intersections The three major intersections were analyzed in the Traffic Report. The existing turning movements are shown in Figure 6. The proposed turning movements are presented in Figure 7. The proposed intersection improvements for River Road will be included in a future River Road widening project. The entering traffic volumes for the River Road intersection in the year 2030 indicate the need for a grade separated intersection. Parking, Pedestrians and Bicycle Movements The existing wide right-of-way encourages parking between the existing two lane road and the adjacent homes and businesses. These informal parking spots will be lost when the road improvements are made. The wide right-of-way also currently serves several other uses including: a homeowner parks his large semi-tractor trailer in front of his house, private car sales and Tucson Water parks their maintenance vehicles in the right-of-way while servicing their well. Parking spaces that exist on private property will not be impacted by these improvements. There is existing sidewalk along River Road and Ruthrauff Road. There is also a sidewalk along the east side of La Cholla Boulevard from River Road to the south side of the Rillito River bridge. Sidewalks along both sides of La Cholla Boulevard from Ruthrauff Road to River Road will be part of the proposed improvements. Sidewalks will be extended south of Ruthrauff Road to the point where the lanes begin tapering and the curb and gutter is terminated. This will include new sidewalk down to the bus stop located on the west side. While space in the right-of-way is reserved for sidewalks during a roadway improvement project, along vacant properties the sidewalk is typically constructed by the developer when they develop their property. There are currently four to six-foot wide paved shoulders along La Cholla Boulevard which serve as bike lanes. The five to six-foot paved shoulders to be built with this project will continue to serve as bike lanes. “Bike Route” signs and pavement markings will be provided. Both pedestrian and bicycle access will be maintained to the Rillito River linear park. 13 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 6. Existing Traffic Conditions 14 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 7. Future Traffic Conditions 15 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 4.2 Accidents Crash data were obtained for the 3-year period from 2004 to 2006. During this period, there were 12 accidents on the roadway segment between Ruthrauff Road and Curtis Road, and 13 accidents between Curtis Road and River Road. The average crash rate for this roadway section of La Cholla was 1.29 crashes per million vehicle miles. Accident data for the intersections are kept separately and breakdown as shown in Table 2: Table 2. Accident Data Intersection Number of crashes with La Cholla Boulevard (2004–2006) Ruthrauff Road 4.3 50 Noreen Street 3 Calle Narciso 1 Jay Avenue 2 Curtis Road 34 River Road 105 River Road Safety Assessment The Arizona Department of Transportation (ADOT) prepared a Road Safety Assessment for the River Road/La Cholla Boulevard intersection. PCDOT reviewed this report and determined that the following recommendations should be incorporated into this project: • Restripe the southbound approach to place the bike lane between the right-turn lane and the painted gore. • Restripe the southbound departure leg to place the bike lane against the curb with a painted gore between the bike lane and the through lane. • Prohibit left turns out of the office park driveway on La Cholla Boulevard south of the intersection with a median. • Construct a southbound right turn lane onto Curtis Road from La Cholla Boulevard. • Provide ADA-compliant pedestrian signal push buttons with proper refuge locations at the Curtis Road/La Cholla Boulevard intersection. • Provide bus pullout on La Cholla Boulevard, south of River Road by means of a widened shoulder. 16 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 5.0 Design Standards and Criteria 5.1 Geometric Standards The roadway will be designed in accordance with AASHTO‘s A Policy on Geometric Design of Highways and Streets (Reference 2), the Pima County Roadway Design Manual (Reference 3), and AASHTO’s Roadside Design Guide (Reference 4). 5.2 Design Standards Design standards for this project include the Pima County Roadway Design Manual (Reference 3), the City of Tucson/Pima County Standard Details for Public Improvements (Reference 5), AASHTO’s Guide for the Development of Bicycle Facilities (Reference 6), FHWA’s Manual on Uniform Traffic Control Devices (Reference 7), and AASHTO’s Standard Specifications for Highway Bridges (Reference 8). 5.3 Slope Standards Most slopes behind the sidewalk will be 4:1. Where a steeper slope is needed to avoid or minimize right-of-way acquisition, a maximum slope of 2H:1V will be used. The geotechnical study (Reference 10) recommended that temporary cut or fill slopes not exceed 1.5H:1V for stability. 5.4 Pavement Structure Using the information contained in Section 3.13 of the Pima County Roadway Design Manual (Reference 3), a Pavement Design Report (Reference 14) was prepared. The design criteria are as follows: • Design period – 20 years • Design R-Value – 45 • Resilient modulus – 21,120 psi • Seasonal variation factor – 1.6 • Level of reliability – 95% • Change in serviceability index – 1.4 • Minimum Structural Number for Arterial Roadway – 2.64 5.5 Design Speed The design speed for this project is 50 mph. It will be posted at 45 mph. 5.6 Drainage Design The drainage design criteria applied for this project has been compiled from the scope of work and Pima County’s Roadway Design Manual, Reference 3. It has been summarized here: 17 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Rillito River. The new bridge will be designed to convey the 100-year flow without raising the floodplain significantly nor allowing it to be higher than the existing bank protection. The low chord of the new bridge will be placed at least two-feet above the 100-year water surface. The depth of the bridge piers and abutments will accommodate scour from a 500-year event. Offsite Drainage. Offsite drainage facilities will convey a 50-year storm under the roadway while containing the 100-year event with no more than a one-foot depth in flowing or ponded water within the roadway. Runoff from a 100-year storm shall not be allowed to overflow to adjacent basins. Onsite Drainage. Onsite or pavement drainage facilities shall convey the 10-year flows. The Pima County standards require that at least twenty feet in each direction be free from flooding during the 10-year flood which allows for a flow spread of up to 20 feet. Storm drains that convey a combination of pavement drainage and cross drainage will be sized for a 50-year storm. During a 100-year storm, flowing or ponded water must not exceed one-foot in depth within the roadway. 5.7 Access Control In general, this roadway will not be access-controlled. The only exception will be that driveways will not be allowed within 150 feet of the curb line of the major intersecting streets (River Road, Curtis Road and Ruthrauff Road). Exceptions may be made for existing driveways on a case by case basis. Also, frontage roads will be provided for the single family homes between Noreen Street and Jay Avenue so they will not have to back out directly into the La Cholla Boulevard traffic. See Subsection 10.1 for additional discussion on the use of frontage roads. 5.8 Cross Section Elements The roadway classification for this section of La Cholla Boulevard is urban arterial. It will be designed to AASHTO and PCDOT standards as shown in Table 3. Table 3. Cross Section Elements Typical section Width Inside traffic lane 12 feet Middle and outside traffic lane 11 feet Right turn lane 13 feet Left turn lane (against curb) 13 feet Left turn lane 12 feet Bike lane 6 feet (5 feet in frontage road area) Median 20 feet (18 feet in frontage road area) Clear zone 20 feet from vehicle travel lane per AASHTO (Reference 4) Sidewalks 5 feet wide on each side of road. Note: See Figure 3. Turn lanes will be provided at the River Road, Curtis Road and Ruthrauff Road intersections as recommended in the Traffic Report discussed in Section 4 of this report. 18 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 5.9 Roadway Geometrics Based upon the 50 mph design speed, the minimum radius that will be used with a 4% superelevation is 926 feet. The minimum horizontal curve length will be 500 feet. Angle breaks of 1˚ 08’ or less may be used in lieu of a horizontal curve. The maximum grade shall not exceed 3%. Since the new road will be curbed, the minimum grade shall be 0.5%. 5.10 Right-of-Way Width The existing minimum right-of-way width of 150 feet will be maintained for the new roadway. The only new right-of-way that will be needed is at the Curtis Road intersection to provide room for the new turn lanes and near the new bridge to provide room for paths connecting the new sidewalk to the Rillito River Linear Park. 19 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 6.0 Major Design Features 6.1 Horizontal and Vertical Alignment The construction centerline of La Cholla Boulevard will follow the section line. The only angle break will be at the quarter corner in Curtis Road where a 0º 0' 10" deflection will be required to keep the road centerline on top of the section line. The new roadway profile generally follows the existing grade except at the bridge where it has been raised to accommodate the deeper girders and provide more freeboard. Stage I (15%) construction plans are included as Appendix C. 6.2 Access Control There are 19 residential driveways that currently access La Cholla Boulevard. An alignment study was performed to determine how they were to be maintained and is documented in Section 10.0 of this report. Driveways will be provided to every property which currently have their primary access from La Cholla Boulevard. On any parcel which does not have sufficient area for a car to turn around, frontage roads will be provided. Backing out into La Cholla Boulevard will not be permitted for safety reasons. Access to vacant properties will be allowed through the normal Pima County permitting processes. The Pima County design guidelines direct that median openings be placed no closer than 660 feet to other median openings. The preferred spacing is 1320 feet. The traffic report recommended four median openings along the project length. At three locations the spacing is closer than 660 feet. The distance from Ruthrauff Road to Calle Narcisco is 587 feet while the distance from Calle Narcisco to Jay Avenue is 579 feet. The median openings at both Calle Narciso and Jay Avenue are vital to neighborhood circulation. The third location is 650 feet south of River Road and is being installed based on the approved development plan. 6.3 Right-of-Way A copy of the right-of-way requirements plan is included as Appendix D. This plan includes the names and addresses of the affected property owners. A summary of the right-of-way acquisition is provided below: Assessor Number Owner Area (Acres) 101-16-117A La Cholla/Curtis Limited Partnership 0.0044 101-13-016C Pima County 0.3022 101-13-015M Pima County Flood Control 0.0181 101-13-015K Unisource Energy Corp. 0.1868 None Unknown (Rillito River) 0.3442 20 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 6.4 Drainage An initial drainage report covering the cross drainage impacts has been prepared by HDR, Inc. (See Reference 9). The first step was to calculate the 50 and 100-year peak flows for each watershed. The results of these calculations as well as the approximate capacity of the existing storm drains are shown in Figure 8. Each of these watersheds were analyzed to determine the type of drainage improvements that would be required to convey the 50-year peak flow under La Cholla Boulevard. Alternative storm drain systems were designed and analyzed. The recommended system is graphically shown in Figure 9. Note that the 50-year peak flows are slightly different than those shown in Figure 8. This is because the 50-year peak flows used for calculating the existing conditions were derived using ratios of the 100-year storm. For determining the size of the new storm drain, rainfall intensities were needed, so the hydrology model was rerun specifically for the 50-year storm resulting in some minor differences. In addition to the new storm drain there will be a new three-span bridge over the Rillito River. The completed bridge will pass a 100-year storm of 32,000 cfs with two feet of freeboard. The new piers will withstand the scour from a 500-year storm (62,000 cfs). A complete summary of the new bridge is presented in Section 6.8 of this report. If the United States Army Corps of Engineers determines that they have jurisdiction over the Rillito River, a Section 404 Nationwide Permit will be required for the bridge construction. A pavement drainage system will also be designed to keep 20-feet of pavement width of La Cholla Boulevard open in each direction during a 10-year storm. 21 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 8. Existing Storm Drain Capacity 22 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 9. Proposed Storm Drain 23 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 6.5 Earthwork Considerations The new roadway profile was based on two main constraints. The first was the need to raise the profile over the Rillito River so that the new deeper bridge structure could be accommodated with two-feet of freeboard over the 100-year floodplain. This will also increase the headroom over the bike paths that cross under the bridge. The second constraint was to match the existing grades along the single family homes with the new frontage road grades to minimize the impact to the front yards of the homes. The new profile generally resulted in excavation along the homes and embankment at the Rillito River bridge. The initial earthwork quantities are 18,300 cubic yards of excavation and 17,400 cubic yards of embankment. Therefore, approximately 900 cubic yards will need to be wasted or hauled out. The draft geotechnical report (Reference 10) recommended that a design R-value of 45 be used for designing the new pavement structure. This should eliminate or minimize the amount of on-site material that is found to be unsuitable as subgrade. It also evaluated the onsite soils for their suitability as trench backfill for the new storm drains and determined that they are suitable both within and outside of the roadway prism. As far as structure backfill and shading material, there are some local areas that may provide suitable material but it is recommended that the contractor assume this material will have to be imported. 6.6 Intersections The proposed improvements for the Ruthrauff Road intersection include dual southbound and eastbound left-turn lanes. Single left turn lanes will be provided for the northbound and westbound legs. Single right turn lanes will be provided at all four legs of the intersection. Of the three southbound travel lanes, one will be trapped into one of the left turn lanes while the other two will continue south through the Ruthrauff intersection. At the Curtis Road intersection, left turn and right turn lanes will be provided for all three legs. Single through lanes will be provided for the east/west leg. At River Road, the new roadway will tie into the existing south leg maintaining the current lane configuration which includes dual left turn lanes and a single right turn lane. The existing east, west, and north legs will remain unchanged. 6.7 Utilities The existing utilities were summarized in Section 3.5. The water and sanitary sewer lines will be impacted by the new storm drain and will be relocated under the roadway contract. The relocation of the gas, telephone and cable TV lines will be performed prior to the road construction. The overhead electric lines will also need to be relocated and this will be accomplished prior to the road work. There is a well site operated by Tucson Water located on the west side of La Cholla Boulevard just south of Jay Avenue. A catch basin will be built in the frontage road to capture the waste water when the well is flushed. No other accomodations will be needed for the well site. 24 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report The high voltage electric line relocation must be performed between September and May. The high pressure gas line relocation must be performed between April and September. If the 16” water line in Ruthrauff Road must be relocated, this work must occur between October and April. The existing bridge supports several utilities including Qwest fiber optic lines in four ducts, two reclaimed water lines used by the Pima County Department of Natural Resources Parks and Recreation (PCDNRP&R) and a Pima County electrical conduit for traffic signals. The PCDNRP&R also owns an electrical conduit with power lines that serve their irrigation controllers in the Rillito River linear park. The traffic signal conduit and the Qwest fiber optics lines will be relocated to the new bridge. No new utilities have been identified as needing to be carried by the new bridge. No prior rights for the facilities located within the public right-of-way, owned by private utility companies, have been identified. Under an existing intergovernmental agreement, half of the water relocation costs incurred by Tucson Water will be paid for by Pima County. Also, all of the sewer relocation costs incurred by the Pima County Regional Water Reclamation Department will be reimbursed by project funding. 6.8 Structures General A Bridge Selection Report (Reference 11) was prepared for the La Cholla Boulevard Bridge over the Rillito River. The existing four-span bridge was constructed in 1981 and carries two lanes of traffic. This bridge will be removed. The new bridge will be constructed along a similar alignment as the existing bridge but will be constructed as two separate side-by-side structures, each carrying three lanes of traffic. A plan and elevation and typical section showing the new and existing bridge are presented in Figures 10 and 11 respectively. The new bridge is located approximately 700 feet south of the River Road intersection. It is possible that this intersection will be rebuilt into a grade separated interchange at some point in the future. This reconstruction may result in a shifting of the traffic lanes on La Cholla Boulevard in the vicinity of the Rillito River Bridge. If this occurs, some retrofitting or reconstruction of the open median between the two bridges may be required. Existing Bridge The existing La Cholla Boulevard Bridge over the Rillito River is scour critical for the 500year superflood event, and therefore, at risk of catastrophic failure during extreme flooding. There is also a significant amount of cracking in the bridge deck which will require the deck to be replaced or retrofit at a minimum in the next ten years. The abutment diaphragms and beams have cracks and spalls that will need to be repaired due to exposed rebar, but these cracks do not affect the overall structural capacity. Larger than normal differential settlement has been seen at the north abutment that causes rideability concerns. Approach guardrails do not meet current safety standards and the bridge barriers are not sufficient for pedestrians or bicyclists. The existing bridge would have to be strengthened for the superflood event and widened on both sides in order to make it viable with the proposed alignment. It has been determined that the existing bridge will be replaced. 25 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Bridge Geometrics The proposed cross section of both the northbound and southbound bridges will be comprised of a 1-foot-wide concrete parapet with pedestrian railing, a 6-foot, ¾-inch sidewalk, a 1-foot, 4¼-inch concrete parapet wall with bicycle railing, a 6-foot shoulder, three 11-foot travel lanes, a 2-foot shoulder and a 1'-7" concrete barrier 3’-6” high along the inside edge of the bridge deck. The north span on the northbound bridge will be flared from 51 feet wide to 61 feet wide in order to accommodate site distances. The open area between the southbound and northbound structures will vary from approximately 20 feet at the south abutment to approximately 21 feet at the north abutment. The distance between the two structures varies because of the 50:1 taper that is required to shadow the proposed dual left turn lanes to the north of the bridge at the River Road intersection. The southbound bridge will have a length of 360 feet and the northbound bridge will have a length of 356 feet between centerline bearing of abutments. There will be three equal spans of 120'-0" and 118’-8 ¼” in the southbound and northbound bridges, respectively. Although the structures have slightly different skew angles, the centerlines of the piers and abutments will be along the same line. The span arrangement has been set so that the new foundations will not interfere with the existing pile foundations of the existing bridge. The new abutments will be set behind the existing abutments and the piers for the new three-span configuration will be placed between the pile foundations of the existing four-span bridge, thereby minimizing conflicts with the existing piles. Fifteen-foot long concrete approach slabs will be constructed at both ends of the bridge. The roadway centerline of La Cholla Boulevard, at the proposed bridge, is on a tangent alignment, bearing N 0° 38' 04" W. The southbound structure will follow this alignment. The northbound structure will not be parallel to the southbound structure, but will follow a tangent with a bearing of N 0° 28' 52" E to accommodate the 50:1 taper that occurs south of the River Road intersection. The proposed vertical alignment will be higher than the existing bridge and will be on a 650foot long crest vertical curve. The approach grade will be +2.22% and the departure grade will be -2.27%. The profile will result in just over two-feet of freeboard under the bridge during the 100-year storm event. The cross slope of the new bridge is 2%. All substructure units will have a skew of approximately 30º to the right, which matches the existing bridge. This will result in hydraulic and scour characteristics which are similar to existing conditions. The configuration of the roadway on the bridge is such that a large median area will exist between northbound and southbound traffic. Two options have been considered for the median area: a closed median and an open median. The closed median option is more visually open and can be easily modified to accommodate future traffic lanes by removing a portion of the raised median curb. However, preliminary cost estimates show that constructing this essentially unused portion of the bridge will cost an additional $1.5 million. The open median option provides the minimum bridge structure required for travel lanes. In this alternative, the median is eliminated and concrete bridge barriers are placed along the inside traffic lanes for the full length of the bridge. These barriers will require impact attenuation devices at the bridge approaches, which will need to be maintained when struck 26 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report by errant vehicles. The cost of the additional barriers and impact attenuation devices, including probable future maintenance, is significantly less than the additional cost of the median bridge structure. It is unlikely that the proposed bridge would need to be widened to the center in the future. The proposed widening will accommodate future traffic projections until at least 2030. In addition, there are no roads in Pima County today that are wider than six lanes. Therefore, because of the cost savings, the bridge will be designed with an open median. Bridge Drainage The watershed area upstream of the bridge is approximately 900 square miles. The 100-year and 500-year peak discharge rates are 32,000 cfs and 62,000 cfs, respectively. The Rillito River in the vicinity of the bridge is approximately 300 feet in top width. The streambed is comprised of medium to fine sand with some gravel and cobbles. A scour analysis for the proposed bridge was done using the Federal Highway Administration HEC-18 (Reference 12) model. Results of the 500-year scour analysis are as follows: 1. 2. 3. 4. Contraction scour = 7.7 feet Local pier scour = 18.3 feet Total pier scour = 26 feet Abutment scour = 23 feet No new channelization will be required. The existing channel cross section at the bridge consists of a 240-foot bottom width with 2:1 soil cement side slopes. The depth of the channel is approximately fifteen feet. In constructing the new bridge the existing 8-feet thick soil cement bank protection will be trimmed as needed to construct the new abutments on both sides of the wash. Excavated soil cement will be replaced with 2000 psi concrete. HEC-RAS (Reference 13) analyses of the proposed and existing bridges were conducted for the 100-year (32,000 cfs) and 500-year (62,000 cfs) flow rates. Results of the HEC-RAS analysis for the proposed bridge are as follows: 1. 2. 3. 4. 5. The 100-year water surface elevation at the upstream face of the bridge is 2260.93 feet. The 100-year flow velocity is 10.0 feet per second. The 500-year water surface elevation at the upstream face of the bridge is 2268.06 feet. The 500-year flow velocity is 11.6 feet per second. 100-year minimum freeboard = 2.0 feet. (Actual freeboard provided = 2.07 feet.) The bridge slopes in two directions, which will drain water off of the roadway and into catch basins along the outside curbs just off the bridge and deck drains equally spaced along the span adjacent to the traffic barrier. The deck cross-slope along with the crest vertical curve will draw water out and off of the bridge deck. Deck drains will also be placed at the base of the concrete parapet at approximately 40 feet on center to allow water buildup on the sidewalks to drain off the edge of the bridge. 27 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 10. Bridge Location Plan and Elevation 28 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 11. Typical Bridge Section 29 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Bridge Utilities There are several utilities within the project limits that are to remain. Only those utilities located on the existing bridge will need to be relocated or deactivated in conjunction with construction of the new bridge. Disruption of affected utilities will be minimized by relocating them to the new bridge before demolition of the existing bridge. Additionally, precautions will need to be taken during construction near the Tucson Electric Power 46KV overhead line that is approximately six feet away from the proposed southbound bridge deck. Specific requirements regarding construction in the vicinity of the powerlines will be included in the construction documents. See Section 6.7 and Figure 11 for additional information regarding bridge utilities. Bridge Substructure Multi-column bents with transverse pier caps and formed concrete columns will be used to provide a structure with similar hydraulic properties to the existing bridge. Spill-through abutments, or stub abutments, will be used at both ends of the new bridge. Soil cement is presently in place to protect the banks of the channel. The existing soil cement will be removed and replaced as required for the construction of the new abutments. Since the new abutments fall behind the existing soil cement, it is anticipated that only a small portion of soil cement will need to be removed to construct the new abutments. Drilled concrete shafts will be utilized to support the abutments and piers. The drilled shafts will have a diameter of 5'-0" at the abutments and the piers. Bridge Superstructure Four different superstructure alternatives and span configurations were considered for the new bridge, including cast-in-place post-tensioned concrete box girders, steel plate girders with a composite deck, precast prestressed concrete box girders, and precast prestressed concrete AASHTO I-Girders with a composite deck. Based mainly on simplicity of construction and minimizing permanent disturbance within the Rillito River channel, the three-span bridge with AASHTO Type V Modified Girders was recommended. The estimated cost for the new bridge is $4.7 million, not including contingencies. 6.9 Pavement Design Based on Section 3.13 of the Pima County Roadway Design Manual (Reference 3), the Draft Geotechnical Report (Reference 10) and the Final Traffic Report (Reference 1), a Final Pavement Design Report (Reference 14) was prepared. The pavement structure recommended for both La Cholla Boulevard and Ruthrauff Road consists of two inches of asphalt-rubber asphaltic concrete over three inches of asphaltic concrete over seven inches of aggregate base. All minor side streets and the frontage roads will be paved with 2.5 inches of asphaltic concrete over four inches of aggregate base. 30 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 6.10 Signalization and Lighting All intersections with side streets having an ADT over 2400 vehicles per day will receive lighting. This will include Ruthrauff Road and Curtis Road. The lighting at River Road will remain as it currently exists. Conduits for future continuous street lighting and ITS along both sides of La Cholla Boulevard between Ruthrauff Road and River Road will be considered during design. The traffic signals at Ruthrauff Road and Curtis Road will be reconstructed to accommodate the proposed intersection widenings. 6.11 Construction Issues The construction phasing scheme will be driven by the need to maintain traffic across the Rillito River. One proposed construction sequencing approach would be as follows: 1. Remove the existing steel railing along the west edge of the existing bridge deck and place temporary concrete traffic barrier a minimum of two feet away from the west edge of the deck. Traffic will remain on the existing bridge as it is today with one lane open in each direction. 2. Construct the new southbound bridge and the west half of La Cholla Boulevard from Ruthrauff Road to River Road. Traffic will be maintained on the existing bridge and on the existing two lane pavement. Additional paving will be added to the east side of La Cholla as required to maintain two lanes of traffic. 3. Relocate the utilities that are supported by the existing bridge onto the new southbound bridge. Move traffic to the new southbound bridge and the new roadway built in the previous phase. Remove the existing bridge and the existing pavement. Build the northbound bridge and the east half of La Cholla Boulevard from Ruthrauff Road to River Road. 4. Complete final striping and landscaping. Access to all homes and businesses must be maintained during construction. While driveways are being built, temporary parking may need to be provided to the residents. Refer to Section 6.7 for seasonal considerations related to scheduling of utility relocations. 31 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 6.12 Design Exceptions Introduction The study team compared the geometric design elements of the proposed La Cholla Boulevard improvements and the recommendations contained in AASHTO's A Policy on Geometric Design of Highways and Streets (2004) and the Pima County Roadway Design Manual (RDM). Design exceptions will be discussed in each category. The roadway classification is urban arterial. Lane, Shoulder and Median Widths The proposed lane widths will vary from 11 feet to 12 feet. AASHTO recommends 12 feet for a lane width but finds 11 feet acceptable for a reconstructed arterial. The RDM recommends 12 feet. The outside paved shoulder widths are 6 feet for the main section and 5 feet for the frontage road section. AASHTO recommends 8 feet minimum for an outside shoulder. The RDM recommends 6 feet. The inside paved shoulder width is one foot throughout the project per the RDM. AASHTO does not recommend a minimum as long as the median curb is mountable as it will be on this project. The RDM recommends a median width of 20 feet. An 18-foot wide median width is used in the frontage road area. Vertical Alignment and Stopping Sight Distance For 50-mph, AASHTO recommends a minimum stopping sight distance of 400-475 feet. This project is being designed using the Pima County requirement for stopping sight distance of no less than 475 feet. All new vertical curves for La Cholla Boulevard meet this criteria. Horizontal Alignment and Superelevation AASHTO recommends the superelevation is not to exceed 12% for a high speed urban street. Pima County allows a maximum superelevation rate of 4% for urban streets. There are no curves used on La Cholla Boulevard. The maximum angle point of 1˚08’ specified by the RDM will be adhered to. Design Speed For urban arterial roadways, AASHTO recommends a design speed of 40 to 60 mph. Pima County has specified a design speed of 50 mph for this project. Grades AASHTO recommends a maximum grade of 6% for urban arterials in level terrain. The RDM specifies a maximum grade of 3%, which will be followed. Due to the use of curbs on this project a minimum grade of 0.5% will be maintained. Cross Slope The AASHTO recommended cross slope range for travel lanes is 1.5% to 2.0%. The travel lanes on this project will have a cross slope of 2.0%. 32 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Bridge Width AASHTO states that the minimum clear width for new bridges on arterial streets should be the same as the curb to curb width of the street. That criteria is met on this project. Design Exceptions No design exceptions from the AASHTO controlling design criteria will be necessary. The Pima County design standards that will require an exception are for lane, paved shoulder and median widths. Pima County granted these exceptions to help minimize the right-of-way impacts to adjacent properties. 33 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 7.0 Social, Economic, and Environmental Considerations 7.1 Biological Resources The project has very limited vegetation, but does contain native plant species subject to the County’s Native Plant Preservation Ordinance and the Arizona Native Plant Law. Plants will be preserved in place, salvaged and relocated, or replaced , consistent with the Ordinance and the project landscape plan. The project may affect nesting birds protected under the International Migratory Treaty Act. Bridge demolition outside of the nesting season is recommended, or nest removal and treatment, is recommended to avoid impacts to nesting birds. Preconstruction surveys for burrowing owl will also be needed in suitable habitat for this species. 7.2 Air Quality The project is located in the Tucson Region Carbon Monoxide Limited Maintenance Area. The La Cholla Boulevard widening from River Road to Ruthrauff Road is in conformity and was analyzed for air quality impacts as part of the 2008-2012 Transportation Improvement Plan for Pima County. 7.3 Noise Sensitive receptors in the project area include adjacent residences and the Rillito River Park/Trail. A noise study (Reference 18) was prepared to evaluate the increase in roadway noise resulting from the future change in traffic, year 2030 traffic volumes under the proposed roadway design, consistent with the Pima County Department of Transportation noise procedure (PCNAP, 2008). The project will result in temporary noise impacts during project construction associated with the operation of heavy equipment. Mitigation measures are proposed to minimize short-term construction noise to the extent practicable; however, construction noise impacts will occur. The project will result in an increase in traffic noise at adjacent residences. Rubberized asphalt will be used in roadway construction and will result in a noise reduction. The resulting noise levels will exceed acceptable noise levels, based on the Pima County Noise Abatement Procedure (PC NAP) criteria of 66 dBA, at 29 residential locations north of Ruthrauff Road and at the Rillito River Park. Noise walls are recommended for installation in the medians between the roadway and the frontage roads on both sides of La Cholla Boulevard, and in front of the residences north of Jay Avenue, on the east side of La Cholla Boulevard. Noise walls at the Rillito River Park would not be effective. 34 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 7.4 Hazardous Materials A Phase I Environmental Assessment (Phase I) was conducted to determine whether there are any hazardous materials conditions of concerns within the project area (Reference 16). The results of the Phase I identified potential hazardous materials concerns regarding existing and past service stations, and closed landfill sites, and recommended further evaluation of these sites. A preliminary site investigation involving subsurface investigation and testing was conducted at these sites to determine whether there were any implications for the project (Reference 17). Results indicate that the landfills do not extend into the project right-of-way and that sampling at the service stations did not reveal any contaminants at actionable levels. Therefore, these sites are not a further consideration for the project. 7.5 Historical/Cultural Resources Two previously recorded archaeological sites occur within the project area: the Hodges Ruin (AZ AA:12:18 [ASM]), a large habitation site; and AZ AA:12:29 (ASM) an artifact scatter. Archaeological testing was conducted to assess the subsurface potential for sites and to determine the site boundaries (Reference 15). Testing did not reveal any subsurface features or artifacts associated with AZ AA:12:29 (ASM). The boundary of the Hodges Ruin near the project site has been further refined, and the project limits have been refined to avoid impacts to this site. Nonetheless, potential for subsurface features associated with the Hodges Ruin remain. As a result, archaeological monitoring with 100 feet of the Hodges Ruin will be required. 7.6 Visual/Aesthetic Resources The project will have the greatest change in visual character between Ruthrauff Road and Curtis road by converting a two-lane roadway with unpaved shoulders to a six-lane urban roadway with raised medians, curb, noise walls and a section of frontage roads. Mountain views will remain largely unobstructed, except closest to noise walls. Background views will remain expansive on approach to the Rillito River. Foreground views will be improved by landscaping and other aesthetic improvements along the corridor. 7.7 Neighborhood Impact A range of alternatives were developed for this project. Design alternatives were evaluated with the acquisition of homes on the east and west of La Cholla Boulevard, the acquisition of homes and partial takes on only one side of the roadway, and the roadway widening without the acquisition of homes. The recommended alternative is one that will not require the acquisition of homes. 35 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report The overall neighborhood effects are similar for all the alternatives because they relate to improving traffic flow and modifying access points. The addition of a raised median will require that some residents make U-turns to access side streets, which they presently access via left-hand turns. However, the medians also result in a safer roadway that results from better separating the opposing traffic. Current frontage roads are in poor condition and do not limit access to La Cholla Boulevard. One-way frontage roads will be provided for the residences that directly front La Cholla Boulevard for safe ingress and egress. The project will eliminate use of the right-of-way for parking, which will have to be absorbed on commercial and residential properties and local streets. Access to businesses and residentices will be maintained throughout the construction process. Access to the neighborhood schools, the new park at Curtis Road and the Rillito River Park is a concern expressed at the public open house. To address the access to the schools, sidewalks will be provided to the southern limits of the new curb. From that point to the end of the new pavement, graded shoulders will be built to provide pedestrians with a place to walk outside of the traffic. Access to the two parks will be provided via new pedestrian paths built on all four corners of the Rillito River bridge. 7.8 Community Resource Impact Temporary effects are anticipated during construction and include a loss of access to the portion of the Rillito River Park that passes under the bridge and a loss of bicycle access to La Cholla Boulevard within the project boundaries. Pedestrian detours will direct path-users around construction activities. Based on the traffic study, there is a possible cut-through route along Jay Avenue that will be monitored and, if needed, traffic calming measures should be considered. The project will improve overall connectivity through the provision of improved pedestrian, bicycle, and bus facilities. 36 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 8.0 Public Involvement 8.1 Public Participation Plan A Public Involvement Plan was prepared by Gordley Design Group, Inc and submitted to the County on September 6, 2007. This plan features public information meetings, a Community Advisory Committee, ongoing contact with affected parties, media relations and the development of informational materials. The goals of the plan are to educate the public about the project’s purpose and need, solicit the public’s comments on the project, review public comments and adjust the roadway design concept to address the public concerns to the greatest extent possible and within the constraints of the project, including safety and cost. 8.2 Community Advisory Committee Community Advisory Committee Meetings There have been six Community Advisory Committee (CAC) meetings held to date. The first meeting was held to go over the responsibilities of the CAC. The second, third and fourth meetings were held to discuss the Alignment Alternatives Study. The fifth meeting was held to review the results of the noise study. The sixth meeting was held to review the Draft Design Concept Report and the Draft Environmental Assessment and Mitigation Report (EAMR). The minutes from these six meetings have been enclosed in Appendix B. Future CAC meetings will be held to obtain their input on the construction plans. The CAC will also meet as needed to provide input on the artwork, aesthetic treatments, and other items for which they have jurisdiction. Community Advisory Committee Concerns The CAC has had an opportunity to review many of the features of the proposed roadway. Aspects of the County plan that the CAC is in agreement include: 6-lanes, wider bridge, turn lanes at intersections, inclusion of sidewalk, bike lanes, and bus stops. However, there are a number of significant concerns that the CAC has with the County’s recommended plan. These concerns primarily center on an approximately 1000’ length of La Cholla north of Calle Narciso on the west side and between Noreen Street and Jay Avenue on the east side. These specific concerns are listed on the next page. 37 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report • • • • • • • • • • • • • • • • • Travel lanes Sidewalk Bike lanes Access and u-turns Parking Frontage roads Proximity of roadway to existing buildings HAWK light Alley Accidents Noise Public art Landscape Well site Property values Crosswalks Bus bays These issues are described in detail in the CAC’s letters dated January 15, 2008 and January 31, 2008, copies of which are included in Appendix B. PCDOT believes all of these are important concerns, and responded in the letters dated January 24, 2008 and February 11, 2008, which are also included in Appendix B. The plan the CAC recommends (Alternative D) is a plan developed by PCDOT during the alignment study. Although this is not the plan that PCDOT recommends, it provides added benefits such as lane widths per Pima County’s Roadway Design Manual; increased buffer space for landscape, public art, and noise mitigation; and frontage roads are not required. The disadvantage is the disruption to property owners, renters, and businesses due to the property acquisition required, as well as the cost associated with that acquisition. If additional money is made available for property acquisition on La Cholla, then money must be taken away from other projects. There is also the opportunity cost. If millions of dollars are now made available for property acquisition on La Cholla, could that money be better spent by improving the River Road intersection, or building a closed median on the proposed bridge over the Rillito River, or improvements at Ruthrauff Road and I-10? While the CAC has been fairly unified on their stance, there are varying opinions on these issues within the community. One person wrote at the first Open House, “There needs to be sound barriers between roadway and housing areas.” Similarly, another person noted, “The fact that Pima County sees no need for sound abatement bothers me. I do not believe that this project would be presented to neighborhoods where the “perceived” income of the residents is higher.” In response to what they like best about the project one person shared a contrasting opinion, “No wall being put up.” Another person stated, “Forget the right-of-way purchase!” 38 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Since PCDOT does not have additional funds to allocate to La Cholla, the CAC would like to request that the Board of Supervisors allocate the needed money for property acquisition. This request will go to the Board when they receive the EAMR. 8.3 Public Meetings A public open house meeting was held on March 6, 2008. Approximately 84 people attended this meeting. A summary of the written comments received has been included in Appendix B. A second open house was held on September 11, 2008 to obtain community input on the Draft Design Concept Report and the Draft Environmental Assessment and Mitigation Report. Approximately 50 people attended this meeting. Appendix B also includes a summary of the written comments from the second meeting. There will be at least one more open house public meeting for this project. It will be held after the Stage IV plans have been submitted. The public meetings are publicized through news releases distributed to the appropriate media and through display advertisements placed with the Daily Territorial and Arizona Daily Star a minimum of 15 days prior to each meeting. Meeting announcements are mailed to the project contact list of approximately 750 addresses, which comprise impacted residents and businesses as well as elected officials. Corresponding information is posted on the dedicated project Web site. Sign-in sheets are provided to record attendance at the meetings, and attendees are asked to submit comments on the forms provided at the meetings. Comments submitted during a two-week period following each meeting are documented and summarized for the project team. A public hearing will be held before a meeting of the Pima County Board of Supervisors upon completion of the EAMR. 39 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 9.0 Agency Coordination 9.1 Environmental Review Coordination is anticipated with the following agencies: City of Tucson, Pascua Yaqui Tribe, Tohono O’odham Nation, State Historic Preservation Office (SHPO), Arizona Game and Fish Department (AGFD), U.S. Fish and Wildlife Service, U.S. Army Corps of Engineers, and the Arizona Department of Environmental Quality (ADEQ). Coordination with the tribes and SHPO will be initiated during the cultural resources consultation. Coordination with AGFD through the use of their online Environmental Review Tool was initiated on September 27, 2007. A list of species within three miles of the project vicinity was provided, as well as project related recommendations. During the preparation of the Phase I Environmental Site Assessment, a representative of ADEQ’s Tank Programs Division was contacted via telephone and the pertinent files regarding known underground storage tanks and leaking underground storage tanks cases were reviewed at ADEQ. 9.2 Intergovernmental Agreements The City of Tucson has a proposal to annex an area named “River-La Cholla Annexation District 2”. This area includes La Cholla Boulevard from just north of Curtis Road to Sunset Road. No date has been set for this matter to go to the Mayor and Council. If it is successful, an Intergovernmental Agreement will probably be required. 40 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 10.0 Alternatives 10.1 Location Alternatives Description This section documents an alignment alternative study for La Cholla Boulevard between Ruthrauff Road and River Road. The reason that an alignment study is needed is due to the presence of single family homes located on both sides of La Cholla Boulevard at the south end of the project. These homes don’t have sufficient room on their property to build circular driveways. Therefore, some approach is needed to prevent vehicles from having to back out directly into traffic. The alternatives investigated under this study include the following: Alternative A This alternative involves shifting the La Cholla Boulevard centerline to the east about 40 feet. This provides enough room to build a frontage road to serve the homes on the west side. It would require the purchase of 13 lots on the east side along with some partial takes from other properties. The layout for this alternative is shown in Figure 12 with the typical roadway section shown in Figure 13. Alternative B This alternative involves shifting the La Cholla Boulevard centerline to the west about 40 feet. This provides enough room to build a frontage road to serve the homes on the east side. It would require the purchase of 12 lots on the west side including a City well site along with some partial takes from other properties. The layout for this alternative is shown in Figure 14 with the typical roadway section shown in Figure 15. Alternative C This alternative involves maintaining La Cholla Boulevard centered on the section line as shown in Figure 16. The typical section, as shown in Figure 17, would include an additional pullout lane outside of the bike lane to provide space for the homeowners to back out a car without entering the La Cholla Boulevard travel lanes. Right of way would not be required from either side of the street, but temporary construction easements would be needed to rebuild the driveways. Alternative D This alternative involves maintaining La Cholla Boulevard centered on the section line as shown in Figure 18. However, as shown in Figure 19, no pullout lanes nor frontage roads would be used to provide space for the homeowners to back out a car. Therefore, the fronting residences on both sides of La Cholla Boulevard would need to be acquired. However, no other right of way would be needed. 41 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Alternative E This alternative was created to provide an option in which right-of-way was not required from either side of La Cholla Boulevard. It involves maintaining La Cholla Boulevard centered on the section line as shown in Figure 20. As shown in Figure 21, the median, travel and bike lanes have been reduced in width. According to the Highway Capacity Manual (2002) an 11 foot lane reduces the saturation flow rate by 3% when compared to a 12 foot lane. Also, 16 foot frontage roads are used on both sides as one-way streets. The medians between the frontage roads and La Cholla Boulevard are four feet. If noise walls are required, a median barrier could be placed in the four feet with a noise wall built on top. While no right-of-way must be purchased from the fronting residences, it will be necessary to acquire temporary construction easements to build the small slopes and reconstruct the driveways. As stated in the 2004 AASHTO, A Policy on Geometric Design of Highways and Streets, lane widths typically vary from 10-ft to 12-ft. The 12-ft lane widths are most desirable and should be used, where practical, on higher speed, free-flowing, principal arterials. The AASHTO guide states that 11-ft lanes are normally adequate under interrupted-flow operating conditions at low speeds (45 mph or less). Research on the relationship between lane width and traffic crashes found no statistically significant relationship between lane width and crash rate on arterial streets (Transportation Research Board, NCHRP Report 282, Multilane Design Alternatives for Improving Suburban Highways 1986). Alternative F This alternative also maintains La Cholla Boulevard centered on the section line with the same typical section as Alternative D as shown in Figure 19. However, as shown in Figure 22, instead of purchasing all of the homes on both sides, only certain properties would be bought. These purchased properties would be used to build circular driveways for access to the remaining homes. Under this alternative, a total of eight properties would be purchased. Variations on Alternative E Several variations on Alternative E were also considered and rejected. These variations included the following: • Replacing the median with a continuous two-way, left-turn lane. This was rejected because of the safety concerns of using a seven-lane section on a 50 mph roadway. AASHTO states on page 714 of their 2004 Geometric Design of Highways and Streets, “In general, two-way left-turn lanes should be used only in an urban setting where operating speeds are relatively low and where there are no more than two through lanes in each direction”. • Replacing the frontage roads with direct driveways. Attached to each driveway would be a paved turnaround area built within the right-of-way. • Providing additional openings in the frontage road medians along with left turn bays in the main median. This was rejected because it would force the narrow frontage roads to function as two-way rather than one-way. 42 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report • Widening the frontage roads from 16 feet to 20 feet so they could function as two-way. The median would then be reduced from 18 feet to 10 feet. This caused two problems. The narrowing of the median can’t begin until the south end of the median nose for the left turn bay Calle Narcisco (approximately Station 55+50). This median geometry not only allows for the left turns onto Calle Narcisco, it provides for the required shadowing of the southbound left turns onto Ruthrauff Road. The taper must be at 50:1, therefore, the 10-foot wide median can’t be achieved until approximately Station 57+50. As a result, we are forced to take right-of-way from six homes on the east side and two homes on the west side. Second, since we only have a 10-foot wide median at Jay Avenue, we can’t provide a southbound left turn lane. Therefore, this movement would be forced down to Ruthrauff Road to make a u-turn. • Reducing the four-foot separating medians to two feet and provide 18-foot frontage roads that are two-way. A sub-alternative to this option was using a concrete barrier in place of the two-foot median. The one-way frontage road was determined to be preferred over the narrow two-way for several reasons including: • It is safer operationally at the intersections with the side streets. • It allows the median width to remain at four feet instead of only two. AASHTO recommends a minimum width of four feet. • There is not the confusing headlight interaction between the traffic on La Cholla and the frontage roads. A glare screen was discussed as a possible solution to the headlight problem, but it would be a significant maintenance problem. 43 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 12. Alternative A Plan View 44 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 13. Alternative A Typical Section 45 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 14. Alternative B Plan View 46 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 15. Alternative B Typical Section 47 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 16. Alternative C Plan View 48 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 17. Alternative C Typical Section 49 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 18. Alternative D Plan View 50 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 19. Alternative D Typical Section 51 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 20. Alternative E Plan View 52 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 21. Alternative E Typical Section 53 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Figure 22. Alternative F Plan View 54 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Right-of-Way Cost The estimated cost of the right of way for each alternative was provided by Pima County Real Property. The estimated right of way costs for each alternative are as shown in Table 4: Table 4. Right-of-Way Cost Alternative Right-of-way cost A $4.3 million B $3.6 million C $0.3 million D $3.8 million E $0.3 million F $2.0 million The costs for Alternatives A, B, D and F may be mitigated to some extent since much of the acquisition will be total takes which will have unneeded areas that might be able to be reconfigured and resold. Alternatives A, B, D and F will result in excess property that could be reassembled and resold or it could be used for buffering the adjacent neighborhoods as discussed below. Since the remnant properties are so narrow, Real Property estimates that they would have minimal resale value. Alternatives C and E have no right of way cost, however, they will have some cost for temporary construction easements because the new sidewalk would be only one to four feet from both the east and west existing right of way lines in the area of the single family homes. Alternative F also includes the cost for temporary construction easements on those parcels that are not total takes. Environmental Environmental issues common to all alternatives: All alternatives would require archaological monitoring for construction activities within 100 feet of the Hodges Ruin, including utility work. Alternatives A, B, D and F would acquire residences along the project area. As a result, any buildings acquired would be subject to asbestos and lead surveys and demolition permitting through the National Emission Standards for Hazardous Air Pollutants (NESHAP) program with Pima County Department of Environmental Quality (PCDEQ). Alternative A – The shifting of the alignment to the east would place the roadway closer to a construction waste landfill located in the southeast quadrant of the intersection of La Cholla Boulevard and Curtis Road. Subsurface hazardous materials investigations at the edge of the right-of-way adjacent to the landfill, and revealed minimal material; however, additional material could be present further east, and would require additional investigation. Nonetheless, construction waste landfills are normally less of a concern than general residential landfills. 55 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report A Circle K gasoline station in the northeast quadrant of the intersection of La Cholla Boulevard and Ruthrauff Road would be impacted. Hazardous materials testing did did not reveal any contaminants in the subsurface of the project right-of-way; however, this does not preclude the presence of contaminants in soil beneath this site, and would warrant additional investigation. By acquiring the first row of mobile homes along La Cholla Boulevard, traffic noise would be buffered by distance to the remainder of the mobile homes in the area. Noise mitigation walls would be possible for the remainder of residences. Alternative B – The shifting of the alignment to the west would place the roadway closer to a general residential landfill located in the southwest quadrant of the intersection of La Cholla Boulevard and Curtis Road. Subsurface hazardous materials investigations at the edge of the right-of-way adjacent to the landfill, and revealed minimal material; however, additional material could be present further east, and would require additional investigation. General residential landfills are normally more of a hazardous materials concern than construction waste landfills. A former gasoline station in the northwest quadrant of the intersection of La Cholla Boulevard and Ruthrauff Road would be impacted. Hazardous materials testing did did not reveal any contaminants in the subsurface of the project right-of-way; however, this does not preclude the presence of contaminants in soil beneath this site, and would warrant additional investigation. By acquiring the first row of residences along La Cholla Boulevard, traffic noise would be buffered by distance to the remainder of the residences in the area. Noise mitigation walls would be possible for the remainder of residences. Alternatives C and E – Maintaining the existing alignment and eliminating right-of-way acquisitions would prevent the roadway from approaching either the general residential landfill located in the southwest quadrant of the intersection of La Cholla Boulevard and Curtis Road or the construction waste landfill located in the southeast quadrant of the intersection of La Cholla Boulevard and Curtis Road. Neither the former gasoline station in the northwest quadrant of the intersection of La Cholla Boulevard and Ruthrauff Road nor the Circle K gasoline station in the northeast quadrant of the intersection of La Cholla Boulevard and Ruthrauff Road would be impacted. No buildings would be acquired; therefore, asbestos and lead surveys and demolition permitting through the NESHAP program with PCDEQ would not be required. Noise mitigation through the use of noise abatement walls could not be accomplished under Alternative C. For Alternative E, noise walls could be built on top of the frontage road median barriers. However, the length of the noise walls will be limited by the need for an attenuator at one end and the sight visibility required at the side street intersections. Alternatives D and F – Maintaining the existing alignment and eliminating right-of-way acquisitions in areas other than the residential areas would prevent the roadway from approaching either the general residential landfill located in the southwest quadrant of the intersection of La Cholla Boulevard and Curtis Road or the construction waste landfill located in the southeast quadrant of the intersection of La Cholla Boulevard and Curtis Road. 56 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Neither the former gasoline station in the northwest quadrant of the intersection of La Cholla Boulevard and Ruthrauff Road nor the Circle K gasoline station in the northeast quadrant of the intersection of La Cholla Boulevard and Ruthrauff Road would be impacted. By acquiring the first row of residences along both sides of La Cholla Boulevard under Alternative D, traffic noise would be buffered by distance to the remainder of the residences in the area. Noise mitigation walls would be possible for the remainder of residences, including those north of Jay Avenue on the east side of La Cholla Boulevard. Under Alternative F, since only a few of the residences would be acquired, noise mitigation through the use of noise abatement walls could not be accomplished along the single family homes. Noise walls would be possible north of Jay Avenue. Displacement of Residences Some of the alternatives would require either single family homes, duplexes or mobile homes to be purchased with their residents being required to relocate. Some of the homes are owner occupied while others are rentals. The number of relocations for each alternative is as shown in Table 5: Table 5. Home Acquisition Requirements Alternative Single-family home acquisitions Duplex acquisitions Mobile home acquisitions A 0 3 16 B 11 0 0 C 0 0 0 D 10 3 8 E 0 0 0 F 5 2 2 Impacts to Businesses Impacts to existing businesses consist of either complete acquisition or a partial take in which the business can continue to operate. Under Alternative A, the Circle K on the northeast corner of Ruthrauff Road and La Cholla Boulevard would be a total take. Partial takes would be required from the businesses located along the east side of La Cholla Boulevard, just south of Curtis Road, but they would be able to continue to operate. These businesses include Finish Line Collision Repair Center, Specialty Auto, Montgomery Auto Repair, and Montgomery Automotive & Trailer Sales. For Alternative B, the Family Food Store on the northwest corner of Ruthrauff Road and La Cholla Boulevard would be a total take. There is also a parcel for which a development plan has been submitted to Pima County for a Family Dollar Store. This development is currently on hold. Alternatives C through F do not directly impact any businesses. 57 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Bridge Location Moving the bridge further west under all of the alternatives will create the need to lower the bike path under the bridge and thereby require the reconstruction of the storm drain outfall. Alternative B causes the greatest shift to the west, but the bridge location is similar with all of the alternatives. Impacts to Utilities The impact to the underground utilities will be similar for all of the alternatives. This impact will mainly occur due to the construction of the new storm drain system. This will require the relocation or lowering of water, gas, telephone and traffic signal conduits. Sanitary sewer lines will need to be relocated or replaced with ductile iron pipe at the storm drain crossings. It is the impact to the above ground facilities, including overhead Tucson Electric Power (TEP) lines, in which the alternatives differ. Alternative A will require the relocation of the overhead joint 46 kV & 14 kV electric lines along the east side of La Cholla Boulevard from Ruthrauff Road to just north of Jay Avenue. Between Jay Avenue and Curtis Road, there are another four distribution poles that may need to be moved. However, there will be new rightof-way into which TEP can relocate. This alternative will also impact a valve station for a 4” high pressure gas line owned by Southwest Gas located on the northeast corner of Ruthrauff Road and La Cholla Boulevard. Alternative B will require the relocation of an overhead 46 kV electric line from Calle Narciso to Curtis Road into new right-of-way. This alternative will also move the bridge closer to the large steel TEP poles and overhead lines at the Rillito River. While this shouldn’t require the relocation of the TEP line it will make drilling the new bridge piers more difficult. Alternative B will also impact the Qwest telephone line from Ruthrauff Road to the north end of the single family homes. Although the underground line probably won’t be affected there will need to be relocation of some pedestals. Finally Alternative B would require the relocation of a Tucson Water well site, which must be within 500 feet of the existing location. Alternative C will require the relocation of the overhead TEP lines on both sides of La Cholla Boulevard along the single family homes. However, since new right-of-way is not being purchased, this will put TEP in the position of having to either buy their own easements across the private properties or put their lines underground both of which will be expensive propositions. TEP recently put 1000 feet of 46kV and 14 kV lines underground at a cost of $750,000. Also, the transformer for the Tucson Water well site located on the west side will need a 15’ by 15’ transformer easement on private property if the poles can’t be maintained. Qwest will need 5’ by 5’ easements on private property for their pedestals. The large expense for undergrounding the TEP lines makes it an improbable option. For Alternative E, TEP will need to relocate their overhead lines. This will have to be accomplished by using high, long spans since undergrounding will probably be too expensive. Qwest will need 5’ by 5’ easements on private property for their pedestals. Alternatives D and F will have the least impact to the above ground utilities. 58 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Traffic Operations Alternatives A, B, D and F use standard roadway typical sections that have been successfully used in Pima County. The frontage road provides a secure separation between the vehicles backing out of the driveways and the high speed traffic on La Cholla Boulevard. The roadway section for Alternative C is not typically used locally nor is it described in the AASHTO Roadway Standards. Therefore, PCDOT will probably be assuming an increased liability in using Alternative C. Also, the pullout lane built in Alternative C will be an attractive area for on-street parking which would defeat its ability to be used for its intended purpose. Alternative E uses narrower traffic lanes (11’ versus 12’) and bike lanes (5’ versus 6’). As described previously, while these narrower lanes meet AASHTO requirements, the wider lanes are preferred on high speed arterials. Alternatives C and F are the only alternatives that have residential driveways that connect directly to La Cholla Boulevard. 59 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Alternatives Matrix A summary of the impacts for each alternative is provided in Table 6. Table 6. Alternatives Matrix Criteria Comments A B C D E F Cultural resources There are no known cultural sites in the area of the single family homes. □ □ □ □ □ □ Hazardous materials Alternatives A and B require the acquisitions of existing or old gas stations. They also move the new road closer to old landfills. ۞ ۞ □ □ □ □ Noise impacts on neighborhood Alternatives A, B, D, and E allow for noise wall mitigation, although the extent of walls for E may be limited by sight distance. Alternatives C and F do not allow for walls. □ □ ۞ □ ● ۞ Residential displacements Assumes that relocations from singlefamily homes are more difficult than mobile homes. ● ۞ □ ۞ □ ● Business impacts Alternatives A and B involve total business takes. ۞ ۞ □ □ □ □ Utility impacts These mainly involve costs to Tucson Electric Power. ● ۞ ۞ □ ۞ □ Traffic operations □ □ ۞ □ ● ● Bridge impacts □ ● □ □ □ □ □ □ ۞ □ ۞ ● 17.8 17.8 4.3 3.6 0.3* 3.8 0.3* 2.0 2.4 2.4 2.4 2.4 2.4 2.4 24.5 23.8 20.2* 23.5 20.9* 21.9 Aesthetic impacts Alternatives A, B, and D have plenty of room for landscaping. Construction cost ($ millions) The construction cost difference is minor. Right-of-way cost ($ millions) Estimated cost provided by Pima County. Planning and design cost ($ millions) Total project cost ($ millions) Budget from Regional Transportation Authority is $16.3 million 17.5 17.3 18.2 17.5 □ = no impact or minor impact ● = moderate impact ۞ = major impact * = R/W cost is uncertain because severance damage is unclear. These costs are based on preliminary design plans from the fall of 2007. As design progresses, the estimates are changing as well. Final Direction Considering safety, operations, cost and impacts, PCDOT recommends Alternative E. 60 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 11.0 Conclusions and Recommendations This project should be designed as described in this report. The design criteria to be used are listed in Section 5.0. Other important criteria for this project include: • • • • • • Alignment Alternative E shall be used to prepare the final design. Noise walls shall be designed for those locations anticipated to have a noise level of 66.0 dBA or above in the next twenty years. If noise walls are not feasible, the use of rubberized asphaltic concrete may be considered as mitigation. Existing native vegetation shall be salvaged and replanted in accordance with the Native Plant Preservation Ordinance (NPPO). No new traffic signals are warranted for this project. Existing traffic signals at Ruthrauff Road, Curtis Road and River Road shall be upgraded as necessary to accommodate the proposed roadway improvements. A new bridge shall be designed to replace the existing bridge over the Rillito River. The spans and piers of the new bridge shall be offset from those for the existing bridge to ease construction of the new piers and eliminate the need to pull the old piles. The superstructure shall consist of a concrete deck over Type V (Modified) AASHTO precast concrete girders. Dual left turn lanes shall be designed for the northbound and eastbound legs of the Ruthrauff Road intersections. No additional improvements shall be made to the River Road intersection. 61 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 12.0 Cost Estimate and Budget Considerations The project cost shown in Table 7 below is based on the preliminary design performed to date and will be refined as more detailed plans are prepared. Table 7. Project Cost Task Construction Cost Cost $19,000,000 Artwork $250,000 Right-of-way $500,000 Design and planning $2,400,000 Construction administration $2,800,000 Total $24,950,000 For a breakdown of the construction cost see Appendix A. Note that the construction cost differs somewhat from the costs given previously in Table 6. This is due to the alternatives study being performed in the fall of 2007 and the design has been refined since then. However, the difference in cost between the alternatives shown in Table 6 is still valid. The private utility relocation will be paid for by the individual utility companies, and therefore, is not included in the budget. The utility relocation costs that will be borne by this project have been included in the construction cost. The total cost to Pima County for this project is estimated to be $25.0 million. The budget for the project is currently $20.0 million. 62 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 13.0 References 1. "Final Traffic Engineering Study For La Cholla Boulevard, River Road to Ruthrauff Road", Kimley-Horn and Associates, Inc., February, 2008. 2. "A Policy on Geometric Design of Highways and Streets", American Association of State Highway and Transportation Officials, 2004. 3. "Pima County Roadway Design Manual", Pima County Department of Transportation and Flood Control District, Second Edition, December, 2003. 4. "Roadside Design Guide", American Association of State Highway and Transportation Officials, Third Edition, 2006. 5. "Standard Details For Public Improvements", City of Tucson/Pima County, 2003 Edition, Revised April 19, 2004. 6. "Guide For the Development of Bicycle Facilities", American Association of State Highway and Transportation Officials, 1999. 7. "Manual of Uniform Traffic Control Devices", U.S Department of Transportation, Federal Highway Administration, 2003 Edition. 8. "AASHTO Standard Specifications For Highway Bridges", American Association of State Highway and Transportation Officials, 17th Edition, 2002. 9. "Stage I Drainage Report For La Cholla Boulevard, Ruthrauff Road to River Road W.O No. 4LCITR", HDR, Inc., December, 2007. 10. “Draft Geotechnical Report, La Cholla Boulevard – Ruthrauff Road to River Road”, NCS Consultants, LLC, June 2, 2008. 11. "Draft Bridge Selection Report For La Cholla Boulevard, Ruthrauff Road to River Road W.O No. 4LCITR", HDR, Inc., February, 2008. 12. "Evaluating Scour at Bridges," U.S Department of Transportation, Federal Highway Administration, Hydraulic Engineering Circular No. 18, Fourth Edition, May, 2001. 13. "HEC-RAS River Analysis System User’s Manual," Hydrologic Engineering Center, U.S Army Corps of Engineers, Version 3.0, January, 2001. 14. “Final Pavement Design Report, La Cholla Boulevard, Ruthrauff Road to River Road”, HDR, Inc., July, 2008. 15. “Cultural Resources Assessment of the La Cholla Boulevard—Ruthrauff Road to River Road Project,” Cook, Patricia; Desert Archaeology, Inc., 2008. 16. “Phase I Environmental Site Assessment, North La Cholla Boulevard: West Ruthrauff Road to River Road,” HDR Engineering, Inc., 2007. 17. “Preliminary Site Investigation, North La Cholla Boulevard: West Ruthrauff Road to River Road,” HDR Engineering, Inc., 2008. 18. “Final Noise Report, La Cholla Boulevard, Ruthrauff Road to River Road,” HDR Engineering, Inc., 2008. 63 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report 14.0 Abbreviation and Acronyms AASHTO American Association of State Highway and Transportation Officials ADEQ Arizona Department of Environmental Quality ADOT Arizona Department of Transportation AGFD Arizona Game and Fish Department Corps U.S. Army Corps of Engineers County Pima County DCR Design Concept Report EAMR Environmental Assessment and Mitigation Report EA Environmental Assessment EPG Environmental Planning Group (ADOT) ESA Endangered Species Act FEMA Federal Emergency Management Agency FHWA Federal Highway Administration GIS geographic information system LOS level of service Manual Pima County Department of Transportation Roadway Design Manual (2003) NEPA National Environmental Policy Act NPDES National Pollutant Discharge Elimination System PAG Pima Association of Governments PCRWRD Pima County Regional Water Reclamation Department PLSS Public Land Survey System PS&E plans, specifications, and estimates ROE right-of-entry R/W right-of-way TDM transportation demand management USFWS U.S. Fish and Wildlife Service 64 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Appendix A Construction Cost Estimate La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Appendix B Community Advisory Committee and Public Involvement Information Includes: • Community Advisory Committee meeting minutes • Open House No. 1 Meeting Summary • Open House No. 1 Comment Summary • Open House No. 2 Meeting Summary • Open House No. 2 Comment Summary • Summary of Public Participation Plan • Letter from PCDOT to the CAC dated December 7, 2007 • Letter from the CAC to PCDOT dated January 15, 2008 • Letter from PCDOT to the CAC dated January 24, 2008 • Letter from the CAC to PCDOT dated January 31, 2008 • Letter from PCDOT to the CAC dated February 11, 2008 La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Appendix C Stage I (15%) Construction Plans (Bound Separately) La Cholla Boulevard: Ruthrauff Road to River Road Final Design Concept Report Appendix D Right-of-Way Requirements Plans (Bound Separately)