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A data question really, though there may be a useful geo-processing solution.

Context: I am calculating "drivetime" catchment areas using PgRouting and OSM / OSM2PO. If my employer/client is to use this as information for decisions, then I think the base data needs to be good.

Problem: The fact is that in a large city say, London speed limits exceed traffic speeds due to congestion. Therefore, my polygons are not really valid (except at times of low activity).

Question: Thus, I'd greatly value any help (all ideas good) with how to update my OSM speeds on an area by area or road by road basis. (E.g: Is there crowd-sourced data (from mobiles)? Can I get access to traffic flow data? Has somebody else tackled this?).

Many thanks, John

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A couple of months back, I had tried to find this kind of information, but drew a blank. I know several organization (like Google, TomTom etc) do collect and use this data, but I couldn't find the data even though I was willing to pay for it. –  Devdatta Tengshe Oct 4 '12 at 12:11
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An easy way to approximate the date more appropriately would be to create a lookup table for road types during day parts. For example, if you are trying to analyze distance traveled during rush hour, you could assign the roads in the highway category (that have a posted limit of 60 mph) with a speed of 45 mph (or as appropriate) for the morning and evening rush, but the posted limit speed during the rest of the day. Then you just point your query to the appropriate field and run the analysis with the predicted speed. –  RyanDalton Oct 4 '12 at 14:23
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2 Answers

up vote 2 down vote accepted

Waze is one route - but uses Ordnance Survey data (at cost) in the UK.

http://www.waze.com/wiki/index.php/United_Kingdom

http://www.waze.com/livemap/ (US only)

Sabre Roads is another project (waze links to this)

"perhaps the most complete archive of information on the British and Irish road network"

http://www.sabre-roads.org.uk/wiki/index.php?title=Main_Page

Trafficmaster (at cost)

Those blue long cameras mounted on blue poles is your best source: There are 5,200 cameras - they monitor congestion live http://www.trafficmaster.co.uk/content/1/60/real-time-traffic-information.html

(you will need an account and they will charge you to access to the live data - trafficsales@trafficmaster.co.uk)

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I think I have heard of Trafficmaster (perhaps via NW Analyst?) but not the other sources. I'll be looking into them. Thanks! –  John Steedman Oct 11 '12 at 10:54
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I was looking for the same information and found the following:

They are not live speeds but averages by time and region. You have to dig around a bit but you should be able to assign reasonably accurate speeds to your OSM network in different fields for different conditions.

I'd be interested to find out what you used in the end.

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Any such data sources you know of for U.S. roads, specifically (in my case) the state of New Mexico? (I've looked around a lot, but then I'm not good at web searching.) TKX. –  Catlike Dec 30 '13 at 20:12
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Off the top of my head, check openstreetmap for your area of interest - roads have a max speed attribute that you could use as a starting point for generating average speeds. –  mixedbredie Jan 8 at 19:02
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