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HomeMy WebLinkAboutAECOM-Tech Mem - Cont 933 & 934-8/7/20171 TECHNICAL MEMORANDUM FOR UNIVERSITY AVENUE RECONSTRUCTION FROM MIDWAY DRIVE TO US 63 WATERLOO, IOWA CITY CONTRACT NO. 933 & 934 Prepared For: City of Waterloo, Iowa 715 Mulberry Street Waterloo, Iowa 50703 Prepared By: AECOM 501 Sycamore Street Suite 222 Waterloo, Iowa 50703 June 20, 2017 University Avenue Technical Memorandum Roadway & intersection Design TABLE OF CONTENTS Page INTRODUCTION 1 TYPICAL CROSS SECTION 1 Discussion 1 Technical Details 1 Project Management Team Recommendation 5 -LANE SECTION VS 4 -LANE SECTION 2 Discussion 2 Technical Details 2 Project Management Team Recommendation 3 INTERSECTION DESIGN (ROUNDABOUT VS TRAFFIC SIGNALS) 4 Discussion 4 Technical Details 4 Project Management Team Recommendation 6 SPEED LIMITS 6 Discussion 6 Technical Details 6 Project Management Team Recommendation 6 BUS TURNOUTS AND BUS STOPS 6 Discussion 6 Technical Details 7 Project Management Team Recommendation 8 AESTHETIC IMPROVEMENTS 8 Discussion 8 Technical Details 8 Project Management Team Recommendation 8 SUMMARY 8 60528991/400/06-05-2017/Final - University Tech Memo 06-20-2017.docx June 20, 2017 UNIVERSITY AVENUE TECHNICAL MEMORANDUM CITY OF WATERLOO, IOWA JUNE 20, 2017 INTRODUCTION The University Avenue project extends from Midway Drive to Highway 63 in Waterloo, Iowa. Since the transfer of jurisdiction in 2016, the City of Waterloo has begun preliminary design and reviewed the alternatives presented in the Environmental Assessment (EA). The City of Waterloo has actively sought public input on the proposed alternatives presented in the EA, including a Public Informational Meeting held on March 21, 2017. This Technical Memorandum summarizes the review of key alternative design elements with respect to the project purpose. The project purpose is to reconstruct University Avenue for a 30+ year life, optimize the corridor operations to move people across and through the area safely and efficiently, develop a Complete Street corridor that is functional and appealing for non -motorists and motorists alike, provide opportunities for future aesthetic enhancements, and to support growth and revitalization. The design elements summarized in this memo are typical cross sections, intersection design, speed limit, bus turnouts and bus stops, and aesthetic improvements. TYPICAL CROSS SECTION Discussion: The existing University Avenue corridor is currently a 6 -lane facility with raised medians from Midway Drive to Highway 63. The corridor currently has minimal pedestrian, bicycle and bus accommodations. The existing cross section has 11 -foot lane widths with 2% -foot curb and gutter sections and a 12 -foot median section. As part of the design process, the project team considered both the typical 12 -foot wide lanes and the narrower 11 -foot wide lanes throughout the corridor. The project team also considered sidewalks and shared use path typical widths and cross section locations. Technical Details: Based on current standards and traffic forecasts, the EA recommended a typical 4 -lane section throughout the corridor. The Iowa Statewide Urban Design and Specifications (Iowa SUDAS) recommends typical roadway sections have 12 -foot travel lanes with 3 -foot curb and gutter sections; however, Iowa SUDAS has an allowable typical roadway section with 11 -foot travel lanes and 2 -foot curb and gutter sections. Narrower lane widths may be selected in reduced -speed urban areas to manage or reduce speed and shorten crossing distances for pedestrians. The EA recommended a 16 -foot raised median. The 16 -foot median allows for 12 -foot turn lanes and pedestrian refuge areas to be installed at the intersections. Current design standards require sloped curbs on streets with design speeds greater than 40 mph and standard curbs for design speeds of 40 mph or below. The reduction from a 6 -lane section to a 4 -lane section allows for the addition of shared use path and sidewalks throughout the corridor. The EA proposed a 10 -foot shared use path on the south side of the roadway, with a 6 -foot sidewalk on the north side of University Avenue for pedestrian and bicycle accommodations. The Iowa SUDAS typical shared use path width is 10 feet to accommodate two-way bicycle traffic, and 5 -foot sidewalks are encouraged and required for pedestrian passing at maximum intervals of 200 feet. Project Management Team Recommendation: The recommended typical cross section for University Avenue from Tunis Drive to Highway 63 is a 4 -lane section, with 12 -foot wide lanes, 2 -foot standard sloped curb and gutter sections, and 16 -foot median. The typical cross-section would also have a 10 -foot shared use path on the south side and a 5 -foot sidewalk on the north side of University Avenue. The recommended typical cross section for Midway Drive to Tunis Drive will be discussed in the 5 -Lane Section vs 4 -Lane Section below. 60528991/400/06-05-2017/Final - University Tech Memo 6-20-17.docx -1- June 20, 2017 - I - 12' 510EIVAGK Recommended Typical Cross Section for University Avenue Tunis Drive to Highway 63 O. 12' 12' 16' GL E. 0. 12' 12' _ 10' f11RU 1NRU LANE LANE 2' GURO - ANO &U11ER ME0IAN 72' KOAOVIAY 1NRU f'rIRU LANE LANE - 2' GUKO ANO GU1fEK 5 -LANE SECTION VS 4 -LANE SECTION ,101.11 -u 1RAIL Discussion: University Avenue from Midway Drive to Tunis Drive is currently a 6 -lane cross section with raised median. The EA proposed a 4 -lane cross section with a raised median. On University Avenue between Midway Drive and Tunis Drive, a 5 -lane section was reviewed because of the high number of commercial driveways in this 1,500 -foot long stretch of roadway. The 5 -lane section would benefit the adjacent properties by increasing access to and from the businesses. Technical Details: The 4 -lane section with divided median maintains the limited access restriction currently on University Avenue and reduces the number of conflict points along the roadway by eliminating the left -turn conflicts. A 5 -lane typical section has two lanes in each direction, with a Two -Way Left -Turn Lane (TWLTL) in the center. The 5 -lane section has the potential of increasing the number of crashes due to the increase of conflict points compared to the 4 -lane cross section with divided median. However, the TWLTLs work well on streets with relatively low design speeds, high driveway densities and turning demands. TWLTLs safely reduce delays for through vehicles while allowing full access to the adjacent properties. South Duff Avenue in Ames, Iowa, and 2nd Street in Coralville, Iowa, both have roadways with similar traffic volumes, adjacent land uses and number of access points. These two roadways have benefited from the construction of a 5 -lane section. In discussion with the City Engineer for the City of Coralville, the City has seen a decrease in the number of crashes since the construction of the 5 -lane cross section and has been very pleased with the way the TWLTL has worked on Highway 6. The Director of Public Works for the City of Ames stated he would highly recommend going with a 5 -lane section. He did state there have been issues at some intersections, and the City will be adding medians at the intersections for the dedicated left turns approaching the intersection. In these locations, the driveways will be right-in/right-out. The estimated additional cost of a 5 -lane section from Midway Drive to Tunis Drive versus a 4 -lane section is approximately $50,000. The following table shows a historic comparison between existing University Avenue, 2nd Street in Coralville and South Duff Avenue in Ames. 60528991/400/06-05-2017/Final - University Tech Memo 6-20-17.docx -2- June 20, 2017 University Avenue Comparison to Similar Corridors University Avenue 2nd Street (Hwy 6) South Duff Avenue 17,600-18,900 (2013) 20,000-27,000 (2014) 20,800-26,400 (2015) 27.3 258 45 20.2-40.4 544 35/40 77.8 391 30/40 Project Management Team Recommendation: The recommendation for University Avenue from Midway Drive to Tunis Drive is a 5 -lane typical cross section with a 35 mph speed limit, 12 -foot lanes, and 2 -foot standard rolled curb and gutter sections. It is also recommended to construct medians at the intersections for the dedicated left -turn lanes to control the driveways near the intersections and avoid these conflicts. The TWLTL is recommended to be 16 feet wide to provide adequate room for the 12 -foot dedicated left -turn lanes at the intersections. Recommended 5 -Lane for University Avenue from Midway Drive to Tunis Drive Recommended 5 -Lane Typical Cross Section for University Avenue from Midway Drive to Tunis Drive _ I OE41,i. 14' GL W. 5. 12' J 12' fHKU lHKU LANE LANE — 2' GUKO ANO GUt1EK GL ti. 12' GON1 I NUOUS t11KU iHKU LEft 1U1KN LANE LANE LANE 2' WKS. ANO t&Ut1EK 66' KOAOIYAY 4UL11-USE L' 1KAIL 60528991/400/06-05-2017/Final - University Tech Memo 6-20-17.docx -3- June 20, 2017 INTERSECTION DESIGN (ROUNDABOUT VS TRAFFIC SIGNALS) Discussion: The existing corridor consists of traffic signals at Midway Drive, Progress Avenue, Tunis Drive, frontage road intersection at Casey's, Falls Avenue, Sager Avenue, Ansborough Avenue, Wallgate Avenue and Fletcher Avenue. The intersection of University Avenue and Greenhill Road has on and off ramps. The project team evaluated the costs, safety and economic impacts of both the construction of traffic signals and roundabouts on University Avenue from Midway Drive to Highway 63. Technical Details: Per the 2013 University Avenue Safety Analysis Technical Memorandum, both roundabouts and traffic signals have operational benefits for the University Avenue corridor. Roundabouts reduce the severity and frequency of severe crashes. The reduction is due to eliminating crossing conflict points and reduced speeds through the intersections. Coordinated traffic signals reduce delay throughout the corridor and, per the 2011 University Avenue Traffic Study, signals operated more efficiently for all intersections with the exception of Progress Avenue and Ansborough Avenue, as shown in the table below. Midway Drive Progress Drive Tunis Drive Greenhill West Ramp Greenhill East Ramp Casey's/Becks Falls Avenue Sager Avenue Ansborough Avenue Wallgate Avenue Fletcher Avenue Roundabout & Traffic Signal Comparison B/10.2 B/12.7 Minimal C/26.5 C/23.7 Minimal B/13.2 C/17.0 Minimal N/A 6/11.5 Minimal N/A B/11.3 Minimal A/6.0 C/15.3 Minimal 6/16.7 C/21.1 Minimal A/7.3 B/12.0 Minimal C/36.9 C/23.4 Minimal A/1.6 C/18.0 Minimal 6/19.7 C/16.6 Minimal Source: 2011 University Avenue Traffic Study Severe Severe Severe (impact reduced if intersection moved) Minimal Severe Severe Severe (study completed before bank moved in) Minimal Moderate Moderate Minimal None None None None None None None None None None None Severe Minimal Moderate Improved Moderate Severe Severe Severe Minimal None None The estimated construction cost for a roundabout on University Avenue is $550,000 versus the construction cost of a typical traffic signal intersection of $660,000. However, the estimated construction costs do not include the necessary right-of-way required to construct a roundabout if right-of-way is required. At Progress Avenue, a roundabout will require significant right-of-way beyond the existing right-of-way limits. The roundabout at Progress Avenue would require the total acquisition of two properties identified in the EA at 3840 University Avenue (in the northeast quadrant) and 3909 University Avenue (in the southwest quadrant) and approximately 10,000 square feet of additional right-of-way at 3910 University Avenue (in the northwest quadrant) and 3821 University Avenue (in the southeast quadrant). The two total acquisitions are estimated at $1,620,000. The total acquisition of the two properties would include demolition of the existing buildings and associated relocation costs. The estimated price for commercial fee acquisition is estimated at $21.00/square foot, for an estimated total of $210,000. 60528991/400/06.05.2017/Final - University Tech Memo 6-20-17.docx -4- June 20, 2017 At Ansborough Avenue, construction of a roundabout will create issues with accessing the frontage roads and fire station, along with the right-of-way impacts to the adjacent businesses. The roundabout at Ansborough Avenue had previously been eliminated as an alternative through the EA process due to the impacts. At Wallgate Avenue, the existing traffic has decreased due to the closure of Edison Elementary School in 2011. The school was a traffic generator and, due to the closure, the traffic volumes no longer warrant a traffic signal at Wallgate Avenue. At Hackett Road, the installation of a roundabout would increase access for Hackett Road and the businesses on Hackett Road south of University Avenue. The roundabout at Hackett Road is shown to have minimal right-of-way impacts to the adjacent businesses. The roundabout at Hackett Road may increase the traffic on Hackett Road south of University Avenue; however, discussion on this issue had suggested guide signs may be posted to direct traffic to the north for Greenhill Road access. The City of Waterloo completed a Vissim Simulation comparing a roundabout to the Greenhill Road ramps to evaluate the impacts to the progression of traffic through the corridor. The simulation showed no significant increase in delays for the proposed roundabout compared to leaving the ramps for Greenhill Road in place. The proposed roundabout at Hackett Road would add roughly 3,810 square yards of pavement and have an estimated additional cost to construction of $275,000, with the additional cost of right-of-way estimated at $110,000. The total estimated additional cost for a roundabout at Hackett Road is $385,000. Currently, the University Avenue and Greenhill Road intersection operates safely per the 2013 University Avenue Safety Analysis Technical Memorandum and operates below the state average crash rates for the University Avenue corridor from Tunis Drive to the frontage road intersection at Casey's. Hackett Road Roundabout Greenhill Road Ramps At the south Greenhill Road ramps, the existing ramp traveling from Greenhill Road to eastbound University Avenue has a short merge taper between the ramp and the frontage road intersection at Casey's. The proposed solution to the merge taper would be to add a lane from the ramp to the frontage road intersection. This added lane would be marked as a turn -only lane, with a merge area on the far side of the intersection. Project Management Team Recommendation: The recommended intersection control for University Avenue is the coordinated traffic signal alternative, with the exception of Wallgate Avenue. Both Progress 60528991/400/06-05-2017/Final - University Tech Memo 6-20-17.docx -5- June 20, 2017 Avenue and the Greenhill Road ramps operate safely with the current configuration, and evaluation of the Progress Avenue and Hackett Road roundabouts resulted in increased costs for construction. The Progress Avenue roundabout has substantial costs in right-of-way acquisition and the Hackett Road roundabout has increased costs for construction and potential impacts to traffic with Hackett Road south of University Avenue. It is recommended the intersection of University Avenue and Wallgate Avenue remove the existing traffic signals and control Wallgate Avenue with a 2 -way stop at University Avenue. SPEED LIMITS Discussion: The roadway has a current posted speed limit of 45 mph from Midway Drive to Highway 63. West of Midway Drive, the City of Cedar Falls has decreased the speed limit on University Avenue from 45 mph to 35 mph with the reconstruction. The project team has evaluated the existing speed limit of the corridor and the possibility of lowering the speed limit to create a business -friendly corridor to enhance economic development and to increase safety for all modes of transportation. Technical Details: The speed of a corridor is contingent upon several different factors including, but not limited to, safety, capacity, access points, driver expectation and intersections. The Waterloo portion of University Avenue operates at below-average crash rates with the posted speed limit of 45 mph. The 2011 Green Book recommends urban arterial streets should be designed, where practical, to permit running speeds of 20 to 45 mph. Speeds in the lower portion of this range are applicable to more crowded business areas, such as University Avenue from Midway Drive to Tunis Drive. This section of University Avenue has a number of conflict points with drives directly onto University Avenue; and with a recommended 5 -lane cross section from Midway Drive to Tunis Drive, a relatively lower design speed is appropriate. University Avenue from Tunis Drive to Highway 63 is proposed to be a 4 -lane with raised median and will have partial access control with access to adjacent properties primarily from side -road intersections. The existing frontage roads are designed to separate the local traffic from the higher speed through traffic. Since 2008, the City of Waterloo has invested approximately $2.4 million into the University Avenue frontage roads from Greenhill Road to Ansborough Avenue. These public improvements assist with access control, safety, speed and efficiency of the University Avenue corridor. This section of University Avenue adequately meets driver expectations for a higher running speed due to the minimal driveway conflict points and traffic signal spacing. Project Management Team Recommendation: The recommendation for University Avenue from Midway Drive to Tunis Drive is a posted speed limit of 35 mph. The recommendation for University Avenue from Tunis Drive to Highway 63 is 45 mph. BUS TURNOUTS AND BUS STOPS Discussion: The Metropolitan Transit Authority (MET Transit) operates in both Waterloo and Cedar Falls. The information received from MET Transit indicates that the ridership is highest for the following bus stops: North Star Community Services (3420 University Avenue), Exceptional Persons Incorporated (EPI) (3675 University Avenue), Falls Avenue, and Ansborough Avenue. On University Avenue, two existing bus shelters are located at the Falls Avenue intersection. The project team is evaluating the use and possible locations for constructing bus turnouts as a part of the design. The Bus Stop ADA Improvements Project was originally going to improve a number of bus stops along University Avenue. Bus stop improvements along University Avenue have been pulled from the Bus Stop ADA Improvements Project and will be included with the University Avenue Project. 60528991/400/06-05-2017/Final - University Tech Memo 6-20-17.docx -6- June 20, 2017 EPI/Tunis Drive North Star Community Services Falls Avenue Ansborough Avenue Technical Details: The Transit Cooperative Research Program (TCRP Report 19 - Guidelines for the Location and Design of Bus Stops) recommends bus turnouts have a minimum of 5:1 tapers and stopping area lengths of 50 feet for each standard 40 -foot bus. Bus turnout locations typically include bus shelters with paved bus stops. The MET Transit buses have front -door loading and unloading. The majority of the MET Transit buses are 30 feet in length; however, they do have three buses that are 37 feet in length. The North Star Community Services bus stop currently has the highest ridership. This location currently has front -door service in the mornings and afternoons for Route 8. MET Transit would ideally transition away from front -door pickup and drop-off and would like bus turnouts installed in front of North Star Community Services. The removal of front -door pickup and drop-off improves the bus route efficiency. Routes 6 and 7 have several riders going to and from North Star Community Services, utilizing the bus stops at the frontage road intersection at Casey's and Beck's. The closest location for riders for pickup and drop-off would be a mid -block turnout across from North Star Community Services. The EPI and Tunis Drive bus stop currently has the second highest ridership. The majority of the riders are going to or leaving EPI. The riders would be able to utilize the pedestrian crossings at the Tunis Drive traffic signals. The proposed bus turnout is near the Hanna Cabin Marker in the southeast corner of the Tunis Drive intersection. The bus stops will need to meet ADA requirements and be connected to the shared use path or sidewalk adjacent to the pads. The locations for the bus stops have been selected and approved by MET Transit. When on -street bus stops or bus pads are utilized, it is recommended to have the stops on the far side of the intersection because farside stops have the least effect on capacity, followed by mid -block stops. For 60528991/400/06-05-2017/Fina! - University Tech Memo 6-20-17.docx -7- June 20, 2097 nearside and farside stops, the front or back of the bus shall have a minimum 10 -foot separation from the crosswalk. Project Management Team Recommendation: The recommended locations for bus turnouts are near North Star, with turnout on the north and south sides of University Avenue. The location for the south side turnout will need to be adjusted to be a farside stop at the intersection of the Casey's and Beck's frontage road and University Avenue. The second recommended location for bus turnouts is near EPI, with turnouts on the north and south sides of University Avenue. This location would utilize the pedestrian crossings at the Tunis Drive traffic signal. The bus turnouts and amenities will be designed as part of the University Avenue Project; however, due to funding constraints, the bus turnouts and pads will be constructed and the shelters, benches and other amenities will be delayed until funding is available. The two existing bus shelters at Falls Avenue are recommended to be reused for the Falls Avenue bus stop. AESTHETIC IMPROVEMENTS Discussion: The project team will develop a roadside landscaping conceptual plan for the University Avenue Project. As a part of this work, the project team will identify areas and design concept level aesthetic improvements with preliminary costs, including plantings and streetscape elements. Technical Details: These amenities will need to be located in areas that will not impact the roadway users or block the required sight triangles. The selected plantings will need to consider the existing local conditions of competition, soil moisture and type, available nutrients, etc. Locations for future streetscape elements will be identified in areas that would be highly visible, while not creating conflicts for the roadway users. Project Management Team Recommendation: Recommend developing a landscape design for the future installation, as funding becomes available. SUMMARY The recommendations for the University Avenue Project are as follows: • coordinated traffic signals with a 10 -foot shared use path on the south and a 5 -foot sidewalk on the north; • 5 -lane section with a 35 mph speed limit from Midway Drive to Tunis Drive; • 4 -lane section from Tunis Drive to Highway 63 with a 45 mph speed limit; • bus turnouts at North Star Community Services and Tunis Drive; and • development of a landscape design for future installation, as funding becomes available. The above recommendations for the University Avenue Project follow the project purpose for the reconstruction of University Avenue optimizing the corridor operations to move people across and through the area safely and efficiently. The design is a Complete Street corridor that will be functional and appealing for non -motorists and motorists alike and will provide opportunities for future aesthetic enhancements and support growth and revitalization. 60528991/400/06-05-2017/Final - University Tech Memo 6-20-17.docx -8- June 20, 2017