John Entwistle’s Reply to Conor Johnston: Why 17th Street is an engineered trap.


From:  John Entwistle

Date:  June 17 at 4:21 PM

Subject:  What do I think makes 17th Street between Church and Noe different from all the other streets in the City with rail tracks?

Dear Conor,

Thank you for getting back to me so fast and offering to help. I know there are things that we can do that will make this street safer.

The first step is understanding the problem which brings us to your insightful question. What makes these two blocks different from all the other streets in the City with rail tracks?  You force me to look at the big picture, the City as a whole. So I pondered a bit applying my decades of experience riding MUNI and exploring San Francisco by bike and suddenly it came to me. Most MUNI tracks are on fat streets, usually six lanes wide.


17th Street is one of the narrowest (44 feet) streets in San Francisco to contain two tracks. The only other contender for this title is Carl Street (39 feet) where the N-Judah comes out of the tunnel. To understand further I took my car out late last night and examined that situation first hand. It becomes clear immediately why Carl Street is intrinsically safer than 17th Street despite being five feet thinner.


Carl Street has several mitigating circumstances. Carl Street has a bike lane one block to the South on Parnassus and a fast moving car route one block to the North on Frederick. Carl Street itself does not attract serious car or bike traffic as it isn’t a major path to or from anywhere. That’s not all.


Carl Street uses different rail from 17th Street. Carl Street uses grooved rail which is designed for city streets such that the pavement can be sealed to the rail on both sides for a tight uniform 1.5 inch groove with no pavement erosion. And Carl Street is surfaced from curb to curb in concrete so it is smooth as glass. There is a white line keeping  parked cars to within 7’5″ of the curb. The difference between Carl and 17th Streets is night and day.


That’s kind of technical, wonkish sort of stuff fer sure. Now let’s take a fast glance at the rest of the system.


Once it hits Judah Street the N-train is on a pad in the middle of a very big street that once again has a bike path a block over. Likewise the K, L,and M lines all travel on large streets when they emerge from the Twin Peaks Tunnel. The T-third has a dedicated path in the center of the Street for most of it’s route. As does the F and E lines running the center of Embarcadero. Let’s just figure that everyone is trying their hardest not to hurt tourists on Beach Street. And Market Street is a problem but is also a work in progress with solutions being implemented and debated.


Now let’s look again at 17th Street applying this emerging theoretical framework for evaluation. Being squeezed between the hills to the South and Market Street coming in at an angle from the North 16th Street and 17th Street are real workhorses. They are the East-West route for everyone in this neck of the woods. 17th Street is the main bike thoroughfare as it should be. 16th and 18th Streets are too dangerous. The bikes need to be there and so do the cars.


So how did the tracks get there in the first place? They were temporary in the 1970’s. So the review process was minimal. The plan was to remove the tracks when Castro Street Station opened. Since they were temporary they used a more dangerous less suitable for city streets type of track with a two inch rut carved into the ash fault next to the track for the wheel flange to ride in. Over time that rut eroded into a four inch gap.


Likewise the intersection at Church Street. It is unusually comprehensive and built in a manner that has been massively improved since then. It is blatantly dangerous. You could never get a modern planning body to approve this type of track infrastructure in a civilian crosswalk. Back then this was a poor working class neighborhood and this whole plan was for a temporary detour while they built the stations on Market Street back in the 1970’s. Bike safety was not even a consideration. It was a different world back then. It never occurred to anyone to paint a line limiting cars to within 8 feet of the curb.


So here we are, 2016 and everyone is getting squeezed together on 17th Street: cars, bikes and streetcar tracks. It was never designed to be such and it doesn’t work. This results in an amazing number of accidents because the bikes and the tracks are in direct conflict. There have never been any design changes to this street to mitigate the presence of the tracks. We can’t divert the bikes and cars like on Carl Street but we can look at those MUNI tracks more critically noting that we do have better alternatives at hand for those trains.


Conor, the huge number of ambulance calls generated is the smoking gun. I think these two blocks of 17th Street are more dangerous than most other streets in the City with rail tracks because of the geography, the narrowness of the street, the large and growing number of bikes, the lack of signage or paint to guide them and the design problems inherent in these particular tracks. I believe we should fix this problem ASAP but not stop there. Having lived in Amsterdam I can close my eyes and imagine a similar system as the Dutch have with dedicated bike paths like little highways rolling everywhere.


I know this is ridiculously long but I wanted to answer your question as completely as possible. I’ve lived here a long time but had not a clue of any of this until I dug deeper. Communication is always a challenge. The tumblr blog is a good start. The address is: and it has good quotes from neighbors, graphics and video’s making the point.


The video at the bottom of the blog is from last month showing a tragic accident involving a mom and two kids. MUNI should issue a public apology for causing that situation. They have not done this yet.


I and my neighbors thank SF Board of Supervisors President London Breed and you for your generous offer of assistance in ending this carnage on 17th Street. Would it help if I asked a few neighbors to direct their own stories your way via email? This is a hot topic hereabouts.


Thanks again,


John Entwistle

3745 17th St.

SF CA 94114

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s