How will the Rectangular Rapid Flashing Beacons (RRFBs) impact the traffic flow on Franklin Boulevard? Are these going to be better than signalized intersections? If yes, how?

The RRFBs are pedestrian actuated, meaning they will begin flashing when a pedestrian pushes the button. Once the beacons begin flashing, vehicles are required by law to yield to pedestrians. The flashing beacons will be timed based on walking speed. Once the pedestrian has either reached the median island or opposite sidewalk, the driver may proceed driving through the crosswalk per Oregon Vehicle Code 811.028. This method of controlling the conflict between pedestrians and vehicles at crosswalks is more efficient compared to a signalized intersection because the conflict distance or length the pedestrian has to cross before the driver can proceed driving is split into several pieces. For example, a pedestrian will cross the westbound travel lanes, then the EmX busway, then the eastbound lanes. For people driving westbound, they will only have to stop when the pedestrian is crossing the westbound travel lanes and be able to drive while the pedestrian is crossing the other segments. This would not be the case at a signal. At a signal, the time provided for a pedestrian is timed to allow a pedestrian to cross from one sidewalk to the other. Here is an example of that difference in time: 

At a roundabout, the crosswalk length to cross the westbound travel lanes is 30 feet. Using the recommended 3.5 feet per second walking speed, it will take a pedestrian less than 9 seconds to cross the westbound travel lanes. Adding perception and reaction time to that, a westbound driver will need to wait 12-15 seconds for the pedestrian to clear the crosswalk. 

At a signalized intersection, the crosswalk length to cross from one side of the street to the other is 124 feet. Using the same 3.5 feet per second, the signal would need to provide a minimum of 36 seconds. In addition to that, signals have what is called Lost Time or time where all movements are red. This is to ensure the intersection is clear of conflicts before releasing the next movements and is typically a minimum of 2 seconds. A westbound driver will need to wait a minimum of 38 seconds before getting a green light. 

In addition to the efficiency of the pedestrian and vehicle conflict at a roundabout, other benefits are realized. Shorter wait times (ie 15 seconds versus 38 seconds) will result in shorter queue lengths. This too will provide efficiencies to the drivers by reducing start up times. Start-up time is the time it takes for a driver to perceive the vehicle in front of them is moving and that they can begin moving. Start-up time may only be 1-2 seconds for the second car in the queue or waiting in line however this perception-reaction time compounds so the 10th vehicle in the queue or line has to wait an additional 20+ seconds before they begin to move. The start-up time will be the same for both a signal and roundabout however the roundabout will have much shorter queue lengths compared to a signal.

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1. What is the project?
2. Why is it needed?
3. What is the project area?
4. How has the public influenced the design concept?
5. Why spend this planning effort here and not on other roads more in need of safety improvements?
6. Is the design decided?
7. Why did the City decide to incorporate roundabouts into the concept plan?
8. How will the Rectangular Rapid Flashing Beacons (RRFBs) impact the traffic flow on Franklin Boulevard? Are these going to be better than signalized intersections? If yes, how?
9. How will cars and buses merge into two lanes at the far side of a roundabout?
10. There's a lot of bike traffic crossing Onyx St. How will people walking and biking get across?
11. Will there be enough time for vehicles turning right onto Franklin between Onyx St and 11th Ave to cross into the left-turn lanes to get onto E.11th Ave?
12. On the east end of 15th Ave, will there be any eastbound railway crossing for people walking and biking?
13. How will the Laurel Valley Hill residents access the Franklin Boulevard Corridor? What are some ways that the residents will go in and out of the neighborhood onto Franklin?
14. Will the left-hand turn from Franklin to Orchard be eliminated?
15. How will the access to Market of Choice (MoC) and Hirons for East and West-bound traffic work on Franklin?
16. How will the residents on Sylvan Street access the roundabout at the base of Riverview Street near Exit 192?
17. How will the traffic congestion following MKA events be improved or impacted with fewer traffic Lanes available on Franklin?
18. If businesses along Franklin lose street access or parking, how will the city satisfy the business requirements to operate?
19. How will roundabouts, with their promise of continuous traffic flow, affect the ability of neighborhood residents to turn west from the south side of Franklin?
20. How will the elimination of the south turn from Franklin onto Orchard impact the viability of Market of Choice and Hirons?
21. Will the new pedestrian crosswalk on the west side of Villard that crosses Franklin impede the turning ability of neighborhood residents wanting to turn west on Franklin?