“A two-way left-turn lane (TWLTL) is a street configuration that provides a center lane for left turning vehicles traveling in either direction. A TWLTL removes left turning vehicles from the through lanes and allows vehicles to wait in the center lane until a safe gap in oncoming traffic is available before turning left.” Source: https://www.mass.gov/doc/two-way-left-turn-lanes-informational-guide/download
Uses: • Driveway entrances or side streets are spaced too closely to place dedicated left turn lanes • Heavy volumes of left-turning traffic can cause congestion along the main roadway Source: https://iowadot.gov/design/dmanual/06c-06.pdf
Roadway with TWLTL
Multilane Roadway without Left Turn Lanes Left-Turning Vehicle
Typical Section of a Roadway with One Travel Lane in Each Direction and Two Way Left Turn Lane Source: streetmix.net
Reduced Delay for Through Vehicles Reduced Potential for Rear End and Sideswipe Collisions
Potential for Rear End Collisions Potential for Sideswipe Collisions Increased Separation Between Opposing Lanes of Traffic Reduced Delay for Vehicles Turning from the Minor Street
Two Way Left Turn Lane (TWLTL)
A TWLTL provides increased clarity during emergencies and allows emergency services vehicles to bypass stopped traffic, if necessary. https://www.mass.gov/doc/two-way-left-turn-lanes-informational-guide/download
Separated bike lanes make roads safer for all users according to a 13-year study of 12 U.S. cities. https://www.sciencedaily.com/releases/2019/05/190529113036.htm
Shared Lane Markings
Bus Lane
Shared Lanes
Bike Lane
Buffered Bike Lane
Conventional Bike Lanes
Least Comfortable Source: City of Boston Better Bike Lanes
Bicycle Comfort Scale
Quick-Build
Full-Build
Separated Bike Lanes
TrafficCalmed, Low-Volume Streets
Most Comfortable
Two Way Cycle Tracks are physically separated bike lanes that allow bicycle movement in both directions on one side of the road. Source: https://nacto.org/publication/urban-bikeway-design-guide/cycle-tracks/two-way-cycle-tracks/
Install Two Way Cycle Tracks on streets to connect cyclists with another bicycle facility or destinations to reduce the need to cross the street Barrier reduces risk of ‘dooring’ compared to a bike lane
Typical Section of a Roadway with one Travel Lane in Each Direction and a Two Way Cycle Track Source: streetmix.net
Install Two Way Cycle Tracks on streets with fewer driveways or cross streets on one side of the road Providing two-way bicycle traffic on one-way streets reduces out of direction travel
Dooring: Opening a motor vehicle door into the path of another road user. Barrier creates a protected space for bicyclists and eliminates risk of collisions with overtaking motor vehicles https://schulzelaw.com/wp-content/uploads/2016/07/Door-Zone-Bike-Law-Image.jpg
Provide Two Way Cycle Tracks when buffered bike lanes are not feasible on both sides of the street
Two Way Cycle Track
Provide Two Way Cycle Tracks along roads with high motor vehicle volumes and/or speeds
“A study of Providence, East Providence, Pawtucket and Central Falls found that temperatures in these places can be 13 degrees higher than in neighborhoods with more vegetation and fewer buildings. What’s more, paved roads and parking lots slowly release that trapped heat overnight, so the evening hours aren’t as cool as they otherwise would be. ” Source: https://www.providencejournal.com/story/news/2022/07/29/heat-wave-hotter-providence-ri-urban-low-income-nieghborhoods/10156676002/
Dark surfaces absorb more energy from sunlight than lighter surfaces, which is released over time as heat energy.
Vegetation and soil absorb and release moisture, which cools the air. Trees also provide shade, which has a cooling effect.
Homogeneous residential streets full of concrete and little shade can create “hot spots” within neighborhoods. Shaded residential areas keep neighborhoods cool during summer heat waves and lower the risk of heat-related illness for residents. Long stretches of asphalt and concrete without shade can create harsh conditions for pedestrians.
Source: https://osf.io/jr9b7?view_only=1b5c811777f546bdb808088bfa24735b
The top photo shows a thermometer reading at the corner of Rugby Street and Pavilion Avenue in Lower South Providence that was 103 degrees on July 22- 10 degrees higher than the official temperature for the city. The bottom photo shows the temperature on leafy Benefit Street on the East Side of Providence was 93 degrees on the same day, 10 degrees cooler than in Lower South Providence, where there are few trees. Alex Kuffner/The Providence Journal Source: https://www.providencejournal.com/story/news/2022/07/29/heat-wave-hotter-providence-ri-urban-low-income-nieghborhoods/10156676002/
Causes: • Reduced natural landscapes in urban areas • Urban material properties • Urban geometry • Heat generated from human activities • Weather and geography Source: https://www.epa.gov/heatislands/learn-about-heat-islands
Heat Islands
“A Complete Street is one that provides safe and accessible options for all travel modes- walking, biking, transit and vehicles- for people of all ages and abilities.” Source: https://www.mass.gov/complete-streets-funding-program
Potential Projects Include: • Bike lanes • Transit shelters • Crosswalks and curb ramps
Source: https://srpedd.org/transportation/complete-streets/swansea-complete-streets/#about
Example Complete Street Cross Section Source: streetmix.net
Pedestrian fatalities in the US are increasing each year. Speed is the number one culprit in these fatalities. https://smartgrowthamerica.org/what-are-complete-streets/
Elements of Complete Streets include but are not limited to: Curb Extensions Provide Shorter and Safer Crossings for Pedestrians
Median Islands at Pedestrian Crossings
Sidewalks/Shared Use Paths
Accessible Pedestrian Signals
Bicycle Lanes
Frequent and Safe Crossings for Pedestrians
Narrower Travel Lanes
Safe and Accessible Transit Stops Designated Bus Lanes/ Transit Priority
While Complete Streets are a process and approach to street design, there is no singular design prescription for Complete Streets. Each one is unique and responds to its community context. The context and needs of users are different in rural, suburban, and urban communities, and streets will look different as a result, even when using a Complete Streets approach. Source: https://smartgrowthamerica.org/what-are-complete-streets/
Complete Streets
Complete Streets In Context