Wednesday 20 February 2013

Road closures

Google makes my life better, for free, every day.

Here's something that it could be doing that could improve quality of life in post-quake Christchurch. It's something that should be low cost to implement as it builds on stuff Google's already doing.

Commuting in Christchurch has been a disaster for the last two years. The earthquake knocked a bunch of bridges and roads out for a while; repairs continue. Google knows about the semi-permanent closures downtown and routes traffic around them in Google Maps. But those are the closures that everybody in town knows about. More difficult to deal with are the rolling repairs - some roads will be shut down for a day to a month or more. Following SCIRT on Twitter gives some of these updates. Google Maps is pretty bad at keeping track of the small changes. Individuals can submit road closures, but it can take Google a while to respond.

But we know that Google is already scraping traffic information out of Android devices where users have given permission for Google to see location information. That's how they put up the traffic layers on the driving maps.

How hard would it be to estimate road closures based on changes in traffic movement? If traffic on a road suddenly drops off to nothing, even for users who'd been directed to use that road, odds are awfully likely that the road is now closed. And if traffic starts up on a road again, it's awfully likely that local drivers have noticed that the road's open again. Use forecast traffic combined with actual to scrape out an automated road closure reporting system. Then, route traffic around the estimated closures. Or, just give a pop-up for drivers around something that looks like a road closure: "Hey! Can you confirm for us whether the road you just avoided is actually closed?" And then experience-rate the Android devices, so if somebody starts driving closed roads for the lulz, their data stops updating the forecast.

Seems pretty simple. And it would make life here a bit better. I can't trust that Google, or the Garmin, are sending me by the most efficient route because Google doesn't know that Bridge Street is one-way westbound and that will be until about the end of the year. If Maps sends me from Uni back to home via the south side of downtown, is it because traffic is terrible on the north side of town, or is it because they're banking on my using a closed Bridge Street? When I diverted around a completely clogged Bealey Street this morning, Garmin missed that Victoria Street is today one-way southbound. And surely getting the systems set up for doing it here would let them do it everywhere.

I wish that SCIRT [the body in charge of post quake infrastructure repair] were better able to push closure updates through to Google and Garmin. Letting those systems know when roads are closed, combined with those systems' existing ability to monitor and route around traffic, should work to improve everyone's commute. Can we please please make this so? SCIRT has a few hundred back-office people last I heard. Couldn't one of them have the job of making sure that the main navigation devices know about the road closures?


  1. I haven't had a look at it myself, but someone in the office who had an Android phone mentioned that Google Now app was advising them to leave early due to heavy traffic on the way home. Not sure how real-time that information was or whether it handles road closures, but might be worth a look.

  2. Google Now hasn't done that for me yet... I ought to set that as a sticky widget. But Google Maps and Latitude regularly tell me to go home via Bridge Street. Bridge Street has been one-way-the-other-way since mid January (it was 2-way over Christmas break, and was 1-way for months prior to that).