Whenever we report on a new neighborhood greenway project, the discussion always turns to diversion. That is, how will the project promote or prevent a higher volume of driving on a street specifically set aside by the Bureau of Transportation to have “low traffic volume and speed where bicycles, pedestrians and neighbors are given priority.”
Last week we shared PBOT’s first swing at plans to turn NE Rodney into just that sort of street. And sure enough, many readers asked about diversion.
Reza wrote;
“Can we get some diversion please? Rodney near Russell gets a lot of car traffic from motorists going to Wonder or other nearby establishments continually circling the block for on-street parking.”
Craig Harlow wrote;
“PBOT, please start installing diverters along ALL of the n’hood greenways.”
and Amy Subach wrote;
“Diverters are essential–not speed bumps–if you want to keep cars from blasting down the stop-sign reduced route. I think speed bumps are annoying and ineffective compared to diverters. And since there is never any speed enforcement on the greenways, we need to discourage cars from using them as alternates to major arterials.”
Given what an obvious issue diversion is whenever these projects come up, I had my own hunches as to why PBOT doesn’t talk about them at the outset of a project. First, they’re controversial: Diverters not only force residents to change their behaviors, but they can also have the impact of moving traffic to another street, which almost always riles people up. Second, they’re expensive: Compared to the cost of sharrows, signage, and a few speed bumps, median islands can jack up the price of an otherwise “affordable” project. And third, because of the first two reasons, any talk of diversion can turn a quiet little project into a potential controversy — something PBOT avoids like the plague.
More common for PBOT is to get a project on the ground, then wait and see how traffic patterns evolve. Then, if diversion is needed, they have the data and neighborhood support (a.k.a. political cover) to make it happen. This is how the scenario played out on my street, N. Michigan Ave. Because some neighbors protested a full median diverter at N Rosa Parks Way, PBOT backed away from it. But they promised to come back later and put it in if it was necessary after the other changes were made. It was. So they did. And now all is well and good.
But those are just my hunches, so I decided to ask PBOT directly to find out what they’re thinking. Here’s what Rodney project manager Rich Newlands shared with me (via email), when asked about diversion on Rodney:
Our conventional wisdom is:
- Neighborhood Greenways work simply when speeds are near 20 mph and volumes below 1,000 cars/day. Diversion in other words is not an assumed pre-requsite to achieve those conditions.
- We try to be very careful when using it because sometimes it only diverts traffic from one local street to another (our policy is that diversion is allowable only if it diverts non-local traffic to a higher classification street). It can be tricky to get it to work as intended.
On Rodney:
- Diversion has always been a consideration and still is ‘on the table’.
- There is no traffic volume evidence that there is a significant cut-through traffic issue currently. Planned changes to N Williams may change that, but maybe/hopefully not. Our assumption going in in terms of travel pattern changes was focused on the impact of the new traffic signal at Cook- a semi-diverter is proposed on the east leg of Cook/Williams intersection to address this.
- I did hear a number of comments at the open house that it’s a concern (hope to have the results complied by the end of the week). However the concern was expressed more in reference to the need to retain some N/S stop signs as the answer.
- What was shown at the open house was just a starting point for this dicussion. We have an internal meeting set up this week to discuss next steps and will be meeting with Eliot NA soon to discuss more. I suspect diversion will be one of the main issues we need to discuss further. We may also want to slow down and wait for the Williams changes to happen first in order to have a better handle on how that project relates to Rodney.
So now you know. Despite the absence of diverters in the plans they showed at the open house, PBOT might still install some diversion measures as part of this project. When/if it gets installed, and whether it comes from stop signs (which would be inconvenient for cycling) and/or from medians (which would be inconvenient for driving), remains to be seen.
Stay tuned.