Category Archives: Parking Structures

Interview with Douglas Perlin, author of a2parking Android application

This interview of Douglas Perlin, author of the a2parking Android application for locating Ann Arbor parking structures, was done via email. It is lightly edited to include hyperlinks.

  1. When did you get the idea to do an a2parking application, and how long did it take you to go from idea to first version?

In October or November 2011 I was looking at the a2dda website and happened to see the parking space availability on one of the pages. I thought it would be nice to have a phone app that could pull up the parking availability data.. It took about a week or two to get the first version up on google play. The original version was kind of clunky I used jsoup to extract the data from a2dda web page and wrote a little code to clean it up.

  1. How long has the software been out in the world?

The app was first published to google play on November 11, 2011. Sometime around the opening of the new Library Lane parking structure the data and web page disappeared. I guess a2dda or Republic Parking was upgrading the system. I guess sometime around August 2013 the data was made available through a JSON link but I wasn’t aware of it at that time. For some reason in early March of this year I was thinking about removing the spaces page since it was coming up blank and just leaving the navigation page. I logged into my Google app.things account and there was an email from Republic Parking informing me about the JSON data so I decided to upgrade the app and that’s what you see now.

  1. Who do you envision as using the system?

I guess I never really thought about it. Probably someone from out of town looking for directions to parking structure.

  1. Have you talked at all to the DDA or to Republic Parking?

I never talked to anyone at DDA or Republic Parking. I did send email to DDA from my regular email account to find out what happened to the data in when it disappeared. I got a quick response letting me know that the system was being upgraded. The thing that really surprised me was when my app.things account received and email from Republic Parking with the JSON link information since I never really wrote to them and my email to the DDA was from a different account. Not sure how they found out about the app.

  1. Is there more information you’d like to gather regarding parking data (e.g. pricing, trending of availability, historical or predictive numbers)?

The menu has an information screen choice which lists structures and lots and when one is tapped it will pull hours and pricing from the JSON link. I’m not really tracking the trends or making predictions.

  1. What’s your favorite parking place? Your favorite free place to park?

Hahaa! I’m a local. I’m pretty good at finding free places to park. That being said I prefer to take the bus and cabs when I come into town since its way cheaper than a DUI.

  1. Tell a little bit about yourself and how you got started programming.

I’m retired. I was a Network Administrator/Network Security Officer for many years. Programming is just a hobby and I’m pretty much of a hack at it since I don’t devote a lot of time to it. I started programming on an Apple II in basic. Then as time passed I moved on to more languages like Pascal, C, perl, and then Java. In the case of the parking app I just wanted to learn how to write a phone app.


“a2parking” app provides Android users with access to real time information about Ann Arbor parking structures

A2parking-icon“a2 parking” is an Android application that provides real time updates of available parking spaces in Ann Arbor parking structures. It is based on data published on the Ann Arbor Downtown Development Authority web site, and in addition to showing spaces free in structures it has one-touch access to directions to your favorite lot or structure.

Download from Google Play: a2 parking.

This has been a long time coming; an interview with Steve Smith of Republic Parking in 2008 described the basic outlines of this data.

Ann Arbor Library Lot exit problems on New Years Eve 2013

Kai Petainen writes that the downtown “Library Lot” parking structure so full on New Years Eve that when everyone went to leave it at once, the lines were so long that people’s paid tickets ran out of time. This caused additional delays of up to 45 minutes on exit and confusion as people had to turn around to re-pay.

I have heard of previous times where other unattended structures (notably Liberty Square) have had similar problems with the prepaid ticket system in busy events. I look forward to a postmortem on this at the next Ann Arbor Downtown Development Authority board meeting, January 8, 2014 at noon.

Ann Arbor DDA has a new web site, and real time parking information is available again

The Ann Arbor DDA has launched a new web site, and one of the features of it is a map with information available in real time about parking availability at various structures.

The structures are in a shade of pale blue, and the lots are in pale green; my current location is marked with a bubble.

If you're looking for just space available information, there's a JSON file with that data; you'll have to unpack it to map structures to their ID numbers. I don't know how stable the URL for that data will be ( over time.

As always, if you're going to be fetching a file as part of an application you are building, and you fetch it repeatedly, please cache the data for a reasonable time and use common sense not to surprise anyone with what you are doing.

Public hearing December 7, 2011 to discuss increase of hourly parking rates in Ann Arbor

Notice of Public Hearing

Under Paragraph 8 of the City/DDA Parking Agreement, the public must be provided with an opportunity to speak at a public hearing before changes are made to hourly parking meter rates. A public hearing has been scheduled to elicit feedback on a proposed change to increase the hourly parking meter rate $0.10/hour, from $1.40/hour to $1.50/hour in September 2012.

Wednesday, December 7, 2011 at 12 noon

Ann Arbor Downtown Development Authority Office

150 S. Fifth Avenue, Third Floor Ann Arbor, MI 48104

Partial failure of retaining wall near Earthen Jar, Jerusalem Garden at Library Lot

A portion of a retaining wall failed on March 24, 2011 before 5:00 p.m. at the Ann Arbor "Library Lot" construction project, and Earthen Jar and Jerusalem Garden have been evacuated as a result.

Picture 12

Contractors from Christman, Soil and Materials Engineers, DTE Energy, and Doan Companies were on site at 9:00 p.m. to stabilize the sinkhole that formed when a portion of the retaining wall gave way. 


I spoke with senior project manager Adrian Iraola of Park Avenue Consultants, who got on site about when I did shortly after 5:00 p.m; he said that "any incident is serious", and reported that a portion of the retaining wall had broken as depicted in this photo taken at the site.



Via @mcburton:

I can confirm, the wall beneath Earthen Jar has collapsed a little. lot of people milling around.

The site is located at 319 S Fifth Avenue, on a block that also contains the downtown branch of the Ann Arbor District Library and the downtown branch of the University of Michigan Credit Union.

Previous incidents at the site include

  • March 22, 2011. Teen rescued after falling into hole near University of Michigan Credit Union. (Ann Arbor Chronicle)
  • March 8, 2011. Two steel workers injured after partial collapse of reinforcing steel. (Photos:
  • Late November or early December, 2010. Small breach in southern retention wall near Ann Arbor District Library; no injuries. (

Two businesses are directly affected by this cave-in.

Earthen Jar, at 311 S Fifth Ave, is temporary closed due to the cave-in. Their web site has been updated.

Picture 11
Jerusalem Garden has also closed temporarily. A sign was on their door at 5:00 p.m.


Updates as they are available; as with all stories this will be updated before it's done, and some updates may take weeks should they require FOIA requests to be fulfilled.

The immediate aftermath, some days later:

The Ann Arbor Chronicle story of Sunday, March 27: "Column: Library Lot – Bottom to Top; A retaining wall breach; conference center idea could sink". Dave Askins speaks with a civil engineer and the project manager about the failure of the retaining wall; plus, reading the council tea leaves on whether the project will be approved.

The story of Sunday, March 27: "Ann Arbor conference center proposal: Some say it'll work, some say it won't, City Council must decide". The story runs with a photo which was taken before the retaining wall breach, and the story and its comments omit discussion of the wall and focus on the council decision.

Damn Arbor blames Cthulhu. "You heard it here first friends. All hail our new Mayor Cthulhu."

Update 3: add partial chronology 7:48pm. 3/24

Update 4: add jar, garden links 8:02 p.m. 3/24

Update 5: add J-G sign, accident 3/8, construction worker night photo. 11:22 p.m. 3/24

Update 6: add reverse angle pile closeup, update credits. 12:15 a.m. 3/25.

Update 7: add reference to 3d incident, 12:51 a.m. 3/25.

Update 8: Add Ann Arbor Chronicle, stories of 3/27; Damn Arbor from 3/24.

Edward Vielmetti likes the falafel at Jerusalem Garden and the okra at Earthen Jar. 16 CFR 255 notice: Ali Ramwali, owner of Jerusalem Garden, gave me a Turkish coffee once gratis (and it was delicious). 

Thanks to Matt Burton, Bill Merrill, Ryan Burns, Spencer Thomas, Kip DeGraaf, Lucy Ann Lance, Richard C. Adler, Kyle Mulka, Eric J. Klooster, Joe Minock, Stephen Clark, and the editors of Damn Arbor for their assistance in assembling this story.