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Environmental Modifications to Improve Crossings with No Traffic Control

The design of crossings with no traffic signal or stop sign can be altered to make them easier and safer by shortening the distance to cross, slowing down the traffic, and increasing the likelihood that drivers will yield. A great resource showing suggestions for design improvements, based on research to increase the likelihood that drivers will yield to pedestrians at these crossings, is Improving Pedestrian Safety at Unsignalized Crossings: Appendices B to O (Fitzpatrick, K., Turner, S., Brewer, M., Carlson, P., Ullman, B., Trout, N., Park, E., Whitacre, J., Lalani, N., & Lord, D., 2006 -- TCRP Report 112/NCHRP Report 562 - Improving pedestrian safety at unsignalized crossings. Transit Cooperative Research Program and National Cooperative Highway Research Program, Washington, D.C.: Transportation Research Board).

Meanwhile, photos of some examples I've seen are shown below:


Horizontal deflection:
Traffic can be slowed by requiring it to move right or left rather than go straight -- the tighter the turn required, the slower the traffic. Features that can deflect the traffic include islands, circles, and bulbouts (bulbouts are extensions or "bumpouts" of the sidewalk or curb into the street).


BULBOUTS, CIRCLES and REFUGE ISLANDS

Example 1 --

photo shows a street with two lanes going each way plus a middle turning lane.  Nine vehicles are visible on the street and another is about to enter from a parking lot.


At the street shown here, it was impossible to hear the vehicles far enough away to know whether it was clear to cross all 5 lanes. A blind man who had to cross it with his young son to catch the bus decided it was too risky.



photo shows a mid-block crosswalk of a 5-lane street.  The sidewalk on each side of the street extends one lane into the street (bulbouts).  There is an island in the middle of the street, covering the width of one lane.  The crosswalk from each side is only one lane wide from the bulbout to the refuge island, and it is well marked with 3 signs facing each direction, each with arrows pointing to the crosswalk and indicating pedestrians (one has a picture of a stop sign and says 'stop here for pedestrians').


Several years later, this same street was made much safer for pedestrians by converting the outside lanes to parking lanes and cutting them off with bulbouts (sidewalk extending into the street), and filling in the middle (turning) lane with a refuge islane. Pedestrians only have to cross one lane at a time.

Photo shows the crosswalk, which extends straight across the street from the bulbout to the refuge island (one lane), then turns slightly to the right to cross the refuge island, then continues straight across the next lane to end at the bulbout (sidewalk extension) on the other side of the street.


This photo shows the same crosswalk. The cut-through of the refuge island is at an angle, to encourage pedestrians to face the oncoming traffic before crossing


Example 2 --

Three photos below all show a 3-lane, moderately busy residential through-street where a small circular island and two bulbouts were installed to deflect the traffic, making vehicles turn and slow down.
photo shows a residential street 3 lanes wide, a cirle with plants fills the middle lane, and just before the cirlce from each direction the curb and grass extend in the street (a 'bulbout') for about half a lane, so that approaching vehicles must swerve to the left to miss the bulbout and then must swerve to the right to get around the circle

(below) To the left is a photo of the above street, to the right is a photo that has been revised to show how it looked before the circle and bulbouts were installed..
photo shows the above street from a different angle, with a bus and car going one way around the circle and a car going around the circle the other way (this is a residential street 3 lanes wide, a cirle with plants fills the middle lane, and just before the cirlce from each direction the curb and grass extend in the street (a 'bulbout') for about half a lane, so that approaching vehicles must swerve to the left to miss the bulbout and then must swerve to the right to get around the circle this is the same photo as the last, but the circle and bulbouts have been removed, so it is a 3-lane residential street with a bus and car going one direction, and a car going the other direction


Example 3 --

A circle and bulbouts were installed in the street in the photo below.
photo shows another example of a residential street 3 lanes wide, a cirle with plants fills the middle lane, and just before the cirlce from each direction the curb and grass extend in the street (a 'bulbout') for about half a lane, so that approaching vehicles must swerve to the left to miss the bulbout and then must swerve to the right to get around the circle



Example 4 --

La Jolla Boulevard in San Diego, California (left, below) was 80 feet curb to curb before it was redesigned, the crosswalk is now 13 feet curb to curb (right).
Concept by Michael Wallwork, P.E., Alternate Street Design. P.A.
photo shows an intersection 6 lanes wide -- one lane is for parking, and the middle lane is painted to designate a refuge island an arial view of the same street shows that the intersection has been replaced with a roundabout and the crosswalk moved about a half block away.  At the crosswalk, the middle lane has been replaced with a planter, the right side of the street has been narrowed to only one lane, and sidewalk on the left side of the street extends into the street and blocks the parking lane, making the crossing only one lane to the refuge island and another lane on the other side of the island.


Example 5 --

The three photographs below show a crosswalk that was shortened with a bulbout on one side of the street and a pedestrian refuge island in the middle. However detectable warnings should be installed to help blind pedestrians recognize the areas of refuge.
these 3 photos all show an intersection with a crosswalk from various angles.  The street is 5 lanes wide, including 2 parking lanes.  The crosswalk on one side of the street crosses 2 lanes (one of which is the parking lane), then passes through a refuge island that fills the middle lane, crosses one more lane and then passes through a bulbout (an extension of the sidewalk into the street) which blocks the parking lane these 3 photos all show an intersection with a crosswalk from various angles.  The street is 5 lanes wide, including 2 parking lanes.  The crosswalk on one side of the street crosses 2 lanes (one of which is the parking lane), then passes through a refuge island that fills the middle lane, crosses one more lane and then passes through a bulbout (an extension of the sidewalk into the street) which blocks the parking lane these 3 photos all show an intersection with a crosswalk from various angles.  The street is 5 lanes wide, including 2 parking lanes.  The crosswalk on one side of the street crosses 2 lanes (one of which is the parking lane), then passes through a refuge island that fills the middle lane, crosses one more lane and then passes through a bulbout (an extension of the sidewalk into the street) which blocks the parking lane


ROUNDABOUTS:

For some reason, it is not possible to hear the approaching cars at this crosswalk in Olathe, Missouri (below left) well enough to know whether it is clear to cross, even when it is quiet. A half block away on the same street, a one-lane roundabout was installed (shown below, right). The tight radius slows the traffic, and splitter islands divide the crosswalk into two short crossings. When it is quiet there, it possible to hear the cars well enough to know whether it is clear enough to cross to/from the splitter island. However, if there are not sufficient gaps in traffic to allow it to become quiet, it may still not be possible to recognize when it is clear to cross.
photo shows an intersection with a crosswalk across a street with two wide lanes photo shows a street to the right of a circular lane.  The street has one narrow lane on each side of a refuge island that is about a half lane wide (the refuge island is triangular in shape, and widens to the left of the crosswalk and becomes more narrow to the right of the crosswalk

Roundabouts are not necessarily the solution if they are not designed well, and/or if they are in a noisy environment or traffic is too heavy to provide gaps in traffic that are long enough to be perceived by hearing. The two photos below show a roundabout that was installed a block away from the quiet roundabout shown above. This roundabout is two lanes wide so the crosswalks are twice as long, the turning radius is large enough that the traffic can maintain higher speeds, and loud, constant noise from the highway on the bridge nearby makes it impossible to hear approaching traffic until it is a few seconds away. Thus, if a blind person heard nothing coming and stepped out to cross, there could be a car only seconds away from impact.
In these two photos, a crosswalk crosses two lanes from an island in the middle of the street to the sidewalk.  About 20 feet to our right, our street enters a roundabout (lanes go around a large circle) with another street entering the roundabout from under a bridge.  There is a very gentle curve such that drivers coming from under the bridge do not need to slow down much to make the turn into our street.  The two photos show cars coming from under the bridge and from the other side of the circle, with one car going past our street to continue around the circle. In these two photos, a crosswalk crosses two lanes from an island in the middle of the street to the sidewalk.  About 20 feet to our right, our street enters a roundabout (lanes go around a large circle) with another street entering the roundabout from under a bridge.  There is a very gentle curve such that drivers coming from under the bridge do not need to slow down much to make the turn into our street.  The two photos show cars coming from under the bridge and from the other side of the circle, with one car going past our street to continue around the circle.


CIRCLES
Shown below is a circle in the middle of the intersection, which slows down the traffic because it is large enough to block straight-through vehicles and require them to turn into the perpendicular street before resuming their direction.
photo shows an intersection on a residential street 4 lanes wide, including 2 parking lanes.  The corners are very rounded.  In the middle of the intersection is a circle that is wider than the street, so it extends into the side street, leaving only a narrow lane between the circle and the corners.


Vertical deflection:

SPEED HUMPS

(below) When the left photo was taken in 1994, it was not possible to hear all the approaching cars well enough to know if it was clear to cross, even when quiet (see "Challenge Photo #5").
The photo to the right shows the same intersection today -- now, when it is quiet, the cars can be heard with enough warning. The difference?
photo shows a residential street with two wide lanes.  The street slopes gently down to the right for about a half a block, then turns left and goes uphill -- we can see the street for about a half block beyond the bend at the bottom of the hill. photo shows the same street but there is a white line across the street, barely visible about a block away (half a block from the bottom of the hill.  That white line is actually a raised hump across the road.

A speed hump which had been installed almost out of sight around the bend (below) slows the traffic and makes it possible to hear them with more warning.
photo shows close-up of the speed hump, which extends across the street.  A car approaches it and starts to ride over the hump.


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