June-July News

Why 12 Foot Wider Traffic Lanes Are Not Safer Than 10 Foot Lanes

Traffic Lanes...Wider is Not Better

One would assume that a wider traffic lane would be safer but a recent study by Jeff Speck AICP, LEED-AP, CNU-A, Honorary ASLA provided convincing data to show the opposite to be true.  During a Future of Transportation series Mr. Speck challenged the current conventions that 12-foot traffic lanes are safer than 10-foot lanes. This was especially relevant for city streets with the main problem focused on speed. Simply put, drivers tend to speed when they have more room and when they go faster accidents become more harmful.  

In a new study, Dewan Masud Karmin P.Eng., PTOE, evaluated dozens of intersections in Toronto and Tokyo. His study linked lower crash rates to narrower lanes with 10 to 10.5 foot lanes showing reduced speeds and less severe collisions. 

Narrow Lanes Are Safer

Based on this data, the ideal lane width is around 10.2 feet in Tokyo (3.1 meters) and 10.5 feet in Toronto (3.2 meters). Interestingly crash rates increased as lanes got too narrow and they also rose as lanes got wider. Karim declared that these results “clearly demonstrate why ‘conventional wisdom of lane width’ does not hold up to scientific scrutiny.”

 

Crash rates in Toronto (blue) and Tokyo (green) were lowest in lanes between 10 and 10.5 feet wide.

Tokyo (blue) tends to have narrower travel lanes than Toronto (orange), which might explain why collisions occur there at slower speeds.

Narrow Lanes Still Carry Lots of Traffic

The current rationale for larger lanes is that 12 foot lanes reduce congestion but with proper planning 10 foot lanes can provide a larger benefit as recently demonstrated in New York City. To make way for bike lanes many streets were narrowed, providing a safe alternative transportation option for city inhabitants. 

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Transportation Planning and Traffic Engineering

VN Engineers Inc. offers roadway design services from corridor studies to the management of NEPA style preliminary engineering to environmental studies. We use an integrated team approach to the design process which draws from our construction management experience. With input from our construction staff, our designers are able to produce high quality constructible and biddable plans. Working as a subconsultant we have partnered with dozens of firms to provide traffic, M&PT/MOT, signal and lighting plans. 

  • Planning Services (Roadway/Bike/Ped) 
  • Design of Signalization
  • Traffic Impact Studies
  • Illumination Design
  • Tunnel Illumination
  • Parking Loading and Geometric Design
  • Signing and Pavement Markings
  • Maintenance and Protection of Traffic during Construction
  • Data Collection Origin and Destination Surveys
  • Parking Studies
  • Traffic Management Studies
  • Traffic Calming
  • Traffic Operations Studies
  • Traffic Safety Enhancement
  • Utility Coordination
  • GIS Mapping Services

Reconstruction of I-95 Northbound in the Long Wharf Area, New Haven, CT 92-649

VN Engineers, Inc. is a subconsultant responsible for Operational Analysis and Capacity Analysis for six signalized intersections and three un-signalized intersections using SYNCHRO and Highway Capacity software.  We have collected accident data, summarized in collision diagrams and prepared warrant analysis for four intersections. 

VN also prepared PE report-outlining improvements which address safety and operations to I-84 and the Route 34 and Route 25 intersection, including acceleration lanes, deceleration lanes, taper lengths and the need for turning lanes. The design of three traffic signals and traffic signal improvements for four signalized intersections including quantities and special provisions.

Additionally, we have conducted traffic signing inventory of I-84 and surrounding roadway network.  VN has prepared preliminary and final ground mounted and overhead signing plans, including guide signs, regulatory signs and warning signs as well as any other signs required for the freeway corridor, ramps and local streets.  Prepared quantities and special provisions.

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September News

VN Engineers Wins CSCE ACE Award For Transportation Management Plan

VN Engineers was challenged with researching and addressing various issues with the Lake Avenue and West Street Corridor that are very important to the City of Danbury and its’ surrounding region. The Lake Avenue – West Street Corridor, which is classified by ConnDOT as a principal arterial, is a major feeder road for I-84 as well as a major route to Danbury’s Downtown area.

The purpose of this study was to prepare a systematic assessment and prioritization of Lake Avenue and West Street transportation corridor needs, such that a well-organized final plan of implementation would be available for use in future funding prioritization for design and construction projects.

For this study, existing conditions information was obtained and reviewed including accident data, land use, and traffic volumes. Traffic volume data from the past 12 years was reviewed in order to project existing traffic volumes in the corridor to the future 2032 design year for additional analysis. An evaluation of the roadway network was performed which included capacity analysis and a review of roadway geometry and traffic control devices. The signalized intersections in the corridor were evaluated using SYNCHRO and estimated delays, volume to capacity ratios, and Levels of Service were reported for existing, 2032 “no-build” and 2032 “recommended” scenarios. The low clearance railroad bridge, located over West Street contributes to major operational, safety, drainage, and maintenance issues in the corridor. Solutions to alleviate some or all of the issues at this location were considered and discussed. Access management, along with pedestrian, transit, and bicycle accommodations were also reviewed and recommendations were made for improvements to improve mobility in the corridor for all modes of transportation. Recommendations to address safety, functionality, and aesthetics were all selected to complement each other and provide an updated vision for the corridor. The landscape architecture firm of DALA (Didona Associates Landscape Architecture) also participated on this study and provided a vision of the streetscape design and landscape architecture along the project.

 

CSCE ACEC


Expanded Services with Video and Web Site Production

Based on the needs of key engineering/architectural clients and state agencies, VN Engineers has expanded services to include high-quality video production and website development.  Whether you are looking for a video to summarize a project, fulfill a community outreach effort or highlight an element for a project pitch, VN Engineers can help you with all your video and website efforts. 

Educational Videos (Single and Multiple Series Formats)

Corporate Videos

Public Outreach Videos

Project Summary Videos

Project Website

 

 

 


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August News

VN Engineers Partners with Parson Brinkerhoff on Grand Central Terminal Leak Remediation Project

The Grand Central Terminal Leaks Remediation project will repair water leak infiltration from surrounding buildings, streets and sidewalks into the Grand Central Terminal complex which is vulnerable to water leakage from rain, melting snow or subsurface water sources. It will consist of the viaduct roadway resurfacing, and the 45th street bridge façade work. The project will also improve the 100 year old Grand Central Terminal water proofing protection system. VN Engineers is providing construction engineering and inspection services for this project.

Construction Supervision and Inspection

 Water Proofing 

Roadway Resurfacing


VN Engineers Wins Construction Inspection Project in Florida

In partnership with Kimley-Horn VN Engineers is working with the City of Boca Raton on a Local Agency Program (LAP) that is designed to landscape the intersection of Glades Road and I-95.

Scheduled to start in September and last multiple months. VN Engineers is providing a Senior Inspector to oversee the entire project.

Construction Inspection 

 Landscape

 


Expanding GIS Mapping Services Across Multiple States

At VN Engineers our Geographic Information System (GIS) technology provides the tools for creating, managing, analyzing, and visualizing the data associated with developing and managing infrastructure. Our GIS  civil engineering group manages and share data and turn it into easily understood reports and visualizations that can be analyzed and communicated to others. This data can be related to both a project and its broader geographic context. It also helps organizations and governments work together to develop strategies for sustainable development and supporting all phases of the infrastructure life cycle.

VN Engineers provides a full array of GIS services in CT, NY, FL, RI:

GIS Mapping and Data Collection

Utility Infrastructure Modeling

Sign Management