Thanks to the City of Tempe Streets Dept for contacting me/us about this project. A one mile section of Mill Avenue, from Broadway Road to Southern Avenue, is set to be resurfaced (they call this a “Pavement Preservation”) soon, I think Summer 2017.
This section has edge lines enclosing a small shoulder. (“fake bike lane”). Edge lines generally should not be used on urban arterial roads in this configuration; and especially when they look like bike lanes, and thus are easily confused with bike lanes. The picture of the grate, in the shoulder should be self-explanatory.
Here’s what the City said:
Thank you for your comments on the future resurfacing project on Mill Avenue from Broadway Road to Southern Avenue. We have identified two options: 1) Remove the edge line and widen the travel lanes. (No bike lanes) 2) Add bike lanes by narrowing travel lanes. (5.5’ bike lane, 10.5’ travel lane, 10.5’ travel lane, 10’ two-way left turn lane, 10.5’ travel lane, 10.5’ travel lane, and 5.5’ bike lane.)* * The only issue we have with the above cross-section is we will have to drop the bike lanes 200’ to 300’ in advance of and following the intersections of Broadway Road and Southern Avenue as all available width is taken up by turn lanes. We will not be adding a right turn lane at Broadway Rd but are looking to remove the median island to provide dual left turn lanes. The volumes for the north to west movement have reached the threshold to warrant dual left turn lanes.
So below, I tried as best I could to “unpack” what would happen with the “add bike lanes” option. It’s best understood broken down into three segments because they each have peculiarities:
- The ~ 300′ closest to Southern
- The ~ 300′ closest to Broadway
- The almost 1-mile in between, “mid-block”
The posted speed limit is ???.
Mid-Block Cross Section
The long segment between ~ 300 feet north of Southern Ave to ~ 300 feet south of Broadway Road, about 8/10th of a mile, is the easiest visualize. Mill at Broadway and Mill at Southern are the major arterial street intersections; there are also two less major signalized intersections (Broadmor, and Alamda), as well as numerous minor intersections and driveways.
Here’s a google street view of what it currently looks like. In words, it’s two through lanes in each direction plus a center turn lane; there is an edge line on either side, forming a small shoulder. There is no bike lane, though the shoulder is understood by the majority of police, bicyclists, and motorists to be a bike lane ( #fakebikelane). This is a problem because it’s not wide enough.
The proposal to add designated Bike Lanes would simply narrow the existing 5 travel lanes a bit; I’m not sure of exact existing dimensions but the proposal is to remove something like 3 feet total from the 5 travel lanes, which when added to the existing shoulders can make BLs:
5.5’ BL, 10.5’ travel lane, 10.5’ travel lane, 10’ two-way left turn lane, 10.5’ travel lane, 10.5’ travel lane, and 5.5’ BL
This is fine, except for the grates, mentioned below. The 5.5′ nominally comes from what is typically an approx 1.5′ gutter pan next to 4′ of usable space (see usable-width-and-bike-lanes for more specifics)
Mill at Southern Ave Cross Section
This gets long to explain and a bit hard to visualize. See google maps for existing conditions.
To summarize, the proposal doesn’t change conditions for bicyclists, either for the better or for the worse.
Existing SB — The edge line disappears ~ 350′ from the intersection with Southern Ave; and the whole road widens considerably in order to accomodate extra turn lanes: an additional LTO (so there are double LTOs), and a RTO lane. There is no shoulder beyond the intersection.
Proposed SB — The BL would “drop” (simply end) somewhere around where the existing edge line now ends. There would be a mixing / transition zone; thru bicyclists using the roadway should merge into the middle of the very narrow right-hand through lane.
No one has proposed this, but I will just point out here that since there is no dedicated space for bicyclists beyond the intersection, thru bicycling should NOT be combined with the RTO lane. (for reference about combined turn lanes, see should-warner-road-bike-lane-have-a-combined-turn-lane)
Existing NB — There are two very narrow thru lanes; there is no shoulder, the shoulder begins to re-appear ~ 300′ north of the intersection. There is a bus pullout bay combined with a driveway right turn pocket of about 100′. This extra space can make things more difficult for bicyclists using the roadway.
Proposed NB — No changes, there will be no BL. Where this section meets the mid-block cross section, the right-hand through lane will gradually bend to the left and a BL will appear.
Mill at Broadway Cross Section
This section, like the Mill at Southern Section, will also have no bike lanes. Again, this gets long to explain and a bit hard to visualize. See google maps for existing conditions.
To summarize, the elimination of the shoulder in both directions might be considered by some as a drawback; this however has nothing to do with adding bike lanes, it’s a result of Tempe’s desire to add an additional LTO lane.
Existing NB — There is a small shoulder all the way to the intersection. There are two through lanes and a single LTO; notably there is no RTO lane.
Proposed NB — There will be no BL; the space that was formerly occupied by the small shoulder(s) will be used in part to create a new, second, LTO lane. (the rest of the space will come by narrowing the existing lanes slightly, and getting rid of a small raised median area).
Where the BL ends, perhaps 300′ from the intersection, through bicyclists will have to merge with the right-hand travel lane.
Existing SB — Two very narrow through lanes along with a shoulder that begins at the intersection.
Proposed SB — Same two very narrow through lanes, but the shoulder is eliminated (and no BL).
Drainage along the project area is mostly the kind that’s integrated into the gutter pan and won’t cause any problems for a 5.5′ BL. (some photos here)
There are, however, 3 like the one pictured at right. All three are on the west side of the street (so, southbound) between Broadway and Alameda and would be within the Mid-block cross section segment.
Bike lanes should have a minimum of 4 ft. (1.2 m) of clear pavement width, excluding gutter pans, longitudinal joints, and other obstructions.
— ITE TCD Traffic Control Devices Handbook, 2nd Edition… See usable-width-and-bike-lanes (emphasis added).
I didn’t have a tape measure with me but a BL stripe at 5.5′ from the curb will not have 4′ of clear pavement width in the bike lane.
Other than re-constructing the drainage, which presumably would be rather expensive, another idea would be to place the BL stripe further from the curb — I would suggest narrowing Lane 1 (the left through lane) from the proposed 10.5′ to 10′. The safety virtues of narrowing travel lanes have been much extolled, see e.g. NACTO , or another e.g. The Truth about Lane Widths… no loss of capacity, increase (for everybody) safety, slower peak MV speeds.
Narrowing Lane 2 could also be done but in a sense doesn’t change much because you’re just “robbing peter to pay Paul” (because the total amount of width available to a motorist in Lane 2 overtaking a bicyclist in the BL doesn’t change).
Who are Bike Lanes “for”?
A bike lane (BL) is a preferential use lane; other types of preferential use lanes are, for example, HOV lanes and Bus lanes.
Large majorities of bicyclists prefer to have a BL available for their use; and likewise large majorities of motorists prefer that bicyclists have a BL available (and typically will demand that cyclists use it; this is why fake bike lanes are so detrimental for cyclists, but that’s another story).
As to the question “of who are BLs for?” the common answer is likely to be that they are obviously for bicyclists in order to promote their safety. But in urban contexts this has never been well-established, and is based more on mis-conceptions of how traffic, including bicycle traffic works. The strike-from-behind is a relatively rare crash, and when it occurs catastrophically, it frequently involves a cyclist being struck from behind by a motorist who drifted from a the adjacent lane into a BL or shoulder, and not within a general purpose travel lane. (you can see a list of pure strike-from-behind here; ones where the cyclist and motorist was traveling in the same lane, and if at night, the cyclist was legally lit/reflectored)
Some local / AZ examples of bicyclists struck and killed over the past several years who were riding in a BL (or shoulder; later i’m going to separate out shoulder from BL; most of the shoulders involve rural highways and are somewhat distinct from urban BLs):
- 2009 Allen Johnson / BL
- 2009 Jerome Featherman / BL
- 2011 Albert Eugene Brack / BL (DUI, hit-and-run)
- 2012 Shawn McCarty / BL
- 2012 Marwan Maalouf / BL (hit and run)
- 2012 Terry Lee Brown / shoulder
- 2013 NR / BL (hit and run. Driver found mentally incompetent)
- 2013 Richard Welck / BL (hit and run, DUI)
- 2014 Kris Lee Chambers / BL (DUI)
- 2014 “Mikey” Pendel / shoulder (hit and run, DUI)
- 2014 James Frankiewicz / BL (hit and run, DUI)
- 2014 Helen Brandes-Weeks / BL
- 2015 Raphael D. Sagarin / shoulder (DUI)
- 2015 NR / shoulder (it was noted the driver was distracted)
- 2015 Robert Anderson / BL (hit and run)
- 2016 Donald Neu / BL
- 2016 NR / BL
- 2016 Calvin Ray Sapp / BL (hit and run)
Note that many involve criminal driver behaviors.
There’s more, 2012,13,14,15 are pretty complete; 2016 are pending dataset release in early July. i will need to cull back to get the earlier ones.