4th Street and Woodland Avenue Roundabout
Improve safety and operations at the intersections of W. 4th Street and Woodland and W. 4th Street and Mesa Park.
This website explains the project development process, project features, and supporting information.
Project Development Process
Both intersections are currently stop controlled with full access to and from 4th Street. There are high vehicle speeds on 4th Street, and traffic has a hard time finding gaps to make turns. These attributes pose a safety risk for increased crashes. Due to the steep grade on Mesa Park Road and skew angle at 4th Street, a study was required to develop options for safety and operational improvements.
Intersection Improvement Study Recommendations
- Limit access onto 4th Street to reduce conflict points for entering vehicles.
- Provide bicycle and pedestrian facilities.
- Traffic calming geometry to reduce speeds on 4th Street for entering vehicles.
- Provide a design that accommodates truck traffic as well as emergency response vehicles.
- Include roadway lighting specifically for conflict areas, including pedestrians and bicycles.
- Minimal maintenance landscaping is recommended for any landscaping areas on the project.
- Right-of-way will be required for construction of this project.
Intersection Options Evaluated
Alternative A – Traffic Signal at both Intersections
Alternative B – Roundabout at Woodland Avenue with a median at Mesa Park Road to control access
Alternative C – Roundabout at both Intersections (cost prohibitive due to available space without encroaching onto steep hillsides or private properties)
Preferred Design Concept
Based on a cost benefit analysis, including safety and operations as well as construction and maintenance costs, the preferred alternative selected is the roundabout at Woodland (Alternative B). Below is a figure displaying the intent of the roundabout design, as well as a design visualization to give viewers a feel for how the roundabout will look and operate.
Reduces crashes by 30%
- Reduces number of conflict points from a typical intersection
- Reduces crash severity by greatly reducing head-on and T-bone collisions
- Reduces vehicle speed as vehicles approach the intersection
- Improves traffic flow and decreases time spent at the intersection
- Reduces number of vehicles queueing at the intersection
Reduces Greenhouse Gas Emissions
- Reduces time spent idling at the intersection versus traditional intersection controls
Reduces Operations and Maintenance Costs
- Eliminates costs associated with traffic signals: Power Costs
- Re-Timing and Operation Costs
- Equipment Replacement Costs
Increases Pedestrian Safety
- Reduces time-at-risk for pedestrians by having two-staged crosswalks on each leg by using pedestrian refuge islands
- Pedestrians only have to look at one direction for each crossing
- Reduces vehicle travel speeds at crosswalks
- Provides opportunities for community and corridor placemaking, softening of edges, and visual appeal by using the central islands for landscape features and decreasing the amount of pavement