ROAD DIETS Michael Ronkin Designing Streets for Pedestrians and Bicyclists New Partners for Smart Growth Los Angeles, February 10 2007 1
Classic Road Diet Two-way street: 4 travel lanes 2 + CTL 2
Portland OR 3
Road Diets Which road carries the most traffic? Which road has the higher speed? With a 4-lane road a fast driver can pass others With a 2-lane road the slower driver sets the speed Which road has the higher crash rate? Which is better for bicyclists, pedestrians, businesses? San Antonio TX 4
Road Diets Safety & Traffic Operations Several studies have shown crash reduction: From 7% (Zegeer et al) to 40 % (Iowa) 5
Fewer midblock conflicts Two types of crashes can be avoided with the 3-lane configuration Four-lane undivided Conflict Point Three-lane 6
Fewer intersection conflicts Four-lane undivided Conflict Point Three-lane 7
Better left-turn turn sight distance 8
21 10 3 10 3 21 Total width = 62 6 Valencia Street (SF) - before road diet San Francisco CA 9
8 5 9 10 6 10 + 4 10 6 5 9 8 Valencia Street (SF) - after road diet San Francisco CA 10
Mission District, San Francisco North-South ADTs 25000 20000 15000 10000 5000 0 Dolores Guerrero Valencia Mission S. Van Ness 1998 - before bike lanes 2000 - after bike lanes 11
Valencia Street Bicycle Volumes PM peak hour counts 250 215 bikes/hr 200 150 88 bikes/hr 100 50 0 Valencia St before bike lanes after bike lanes 12
Road diets: reclaim street space for other uses Not just for bike lanes Cambridge MA 13
What are some benefits of road diets for pedestrians? Reduce crossing distance Eliminate or reduce multiple threat crash types Install medians or crossing island to break crossing into 2 simpler crossings Reduce top end travel speeds Add sidewalk buffer from travel lanes (parking or bike lane) Reclaim street space for higher and better use than moving peak hour traffic 14
Room for crossing island Kirkland WA 15
Separation from traffic Salem OR 16
Old centerline Reclaiming road space creates room for islands Portland OR 17
Restriping benefits all users Prolong pavement life (motor vehicles no longer travel in the same well-worn ruts) 18
Keep right-turn turn radius tight 19
Better sight distance Easier to exit from driveways (improved sight distance) Corvallis OR 20
Restriping benefits transit Portland OR 21
A buffer to trees Corvallis OR 22
ROAD DIETS Other configurations 23
On-street parking Median Bike lanes Center turn-lane It s s not one-size fits all: reclaimed road space creates Seattle WA room for many uses 24
NARROW TRAVEL LANES @ 25 MPH: 10-10.5 travel lanes @ 30-40 MPH: 11 travel lanes @ 45 MPH or more (if high truck volumes): 12 outside travel lane Dimensions acceptable to OR State Traffic Engineer 25
Potential As is pretty wide CTL Spartanburg SC 26
Restriped for bike lanes Spartanburg SC 27
Before Corvallis OR 28
Unbalanced traffic flows 29
Old lane line Take advantage of uneven a.m./p.m. peaks Washington DC 30
This 5-lane 5 Main Street was converted to Pottstown PA 31
Name 4 things that changed Fewer travel lanes; added bike lanes; parallel to back-in diagonal parking on one side; new pavement Pottstown PA 32
We don t t like 5-lane 5 streets; What about 7-lane 7 streets? 33
Spartanburg SC 34
Spartanburg SC 35
Spartanburg SC 36
One-way streets HUGE untapped potential HUGE 37
Is this street operating at capacity? Boise ID 38
This area was recaptured from a 4 th travel lane; the street took on a whole new life Portland OR 39
12 T 12 T 12 T 12 T Typical one-way cross-section: Four 12 travel lanes Why? Because the space was there 40
12 T 12 T 11 T 5.5 B 7.5 P Possible scenario #1: Three travel lanes and Bike lane and parking on one side 41
7 P 11.5 T 11 T 11.5 T 7 P Possible scenario #2: Three travel lanes and Parking on both sides 42
8 P 13 T 13 T 6 B 8 P Possible scenario #3: Two travel lanes and Bike lane and parking on both sides 43
Nor radical enough for you? How about we reduce 2 travel lanes to one bi-directional lane and two bike lanes? 44
Old Centerline Single two-way way travel lane with bike lanes Geneva CH 45
Old Centerline Zeeland NL 46
Rotterdam NL 47
Can t t be done here? US Example Albany OR 48
Computer rendering Albany OR 49
Reality check Albany OR 50
Why quote Albert Einstein or Mahatma Gandhi, when you can quote yourself? The best way to prove something can be done is to demonstrate it has been done. Michael Ronkin 51