I have spent a very large amount of time cleaning up TIGER in rural areas of Florida. I agree with others that the vast majority of untouched TIGER ways in un-populated rural areas classified as residential are forest roads for logging trucks at best and pure fantasy at worst, with tons of barely grass paths all over the place. Many of these roads are on private lands that you can't (or shouldn't) access anyway. Spatially accuracy is often horrific. I've reviewed a decent amount of 2017 TIGER and many areas have not been fixed. The best secondary source of data I have found are county streets from the county GIS departments, but those vary widely in quality. At the very least the county data shows you where all the forest tracks, farms tracks and imaginary TIGER streets are, because they are not there in the county data sets. Many times, a residential street having no name is a strong tip as well that it is not a residential street.

Kevin, I hear where you are coming from, but I think your case is somewhat unique. Most people aren't going to look at a GPS with OSM data in it, see a bunch of residential roads in a rural un-populated area and think, OK, that must be unedited TIGER, but I know there's a few navigable roads in there somewhere, I just need to find them, record what I found and make some OSM edits. If they know the area, they are going to think this data is junk. If they don't know the area and they head into it they will then figure out pretty quickly the data is junk. I agree with others that these roads should probably not be in OSM at all - let the locals add the real roads and tracks. But we are living with the old TIGER, and there is some potential usefulness that can come from it. So as others have said, we are willing to leave them there, downgrade them to track without a grade assigned for now, maybe make some spatial corrections, delete roads that are obviously pure fantasy, etc.

I don't think there should be any requirement to cover a certain size area when reviewing these areas. We need to be thankful that someone has taken the time to look at even a small area of rural areas that don't get much attention normally at all, especially private lands.


On 2/12/2018 6:02 PM, Kevin Broderick wrote:
If you can cover an entire area (which I'd define as a swath between the nearest state highways), I agree that downgrading to track absent other clues is one reasonable solution. One of my key points is that anyone who's spent a fair bit of time trying to use GPS maps (of any origin) in poorly-mapped areas will quickly recognize an area that is clearly an unverified TIGER import, which signals both (a) that the data is clearly questionable and (b) that it might be an interesting place to explore to find out if the roads do go through or not. The questionable map data can be very useful, especially in conjunction with other data sources, in attempting to piece together a route through an area that lacks fully maintained roadways. If a track doesn't actually exist, yes, then it should certainly be deleted, but I've ridden right-of-ways that were damn near impossible to see with leaf-on imagery and also found other routes that looked more road-like via the same imagery impassable, so I definitely wouldn't delete anything unless you can get there in person and look for evidence of a roadway, perhaps one that hasn't been maintained in decades (e.g. Class IV roads in Vermont and Class VI roads in New Hampshire).

Downgrading some ways to tracks without doing so to a whole localized network creates the appearance of a higher level of data accuracy than actually exists, which IMO is more likely to bite someone in the ass than having a localized network of roads that are mislabeled. I know it would make some of the exploring I've done via on/off-road motorcycle more difficult.

I'd also suggest that leaving tiger:reviewed at no is appropriate if you haven't been able to travel the road/track in question and determine whether it is really an unclassified road or a track, so it remains flagged for further review if someone has the time and proximity to do so.

On Mon, Feb 12, 2018 at 3:39 PM, Martijn van Exel <m...@rtijn.org <mailto:m...@rtijn.org>> wrote:

    I am very happy to see this rekindled interest in TIGER cleanup!

    Having done a fair amount of backcountry exploring, I know that
    there is a wide range of road grades and aerial imagery alone is
    not enough to decide how navigable a roads is for a particular
    type of vehicle. Or, for that matter, what its access limitations
    are. I do agree with Clifford that leaving them as poorly aligned
    'residential' roads is the worst possible situation. Yes, worse
    than deleting the road altogether. What I usually do is mark the
    road as track without a track grade tag. This seems to me to be
    the most acceptable generic solution for a remote mapper:
    acknowledging that something that could potentially be navigated
    by a 4 wheeled vehicle exists, without being more specific. Local
    knowledge can then come to the rescue to upgrade to unclassified
    if appropriate.

    Another note on the MapRoulette side of things: I would very much
    appreciate your feedback on the new MapRoulette version Clifford
    linked to. Just email me, join #maproulette on slack, or file an
    issue at https://github.com/maproulette/maproulette3/issues


    On Mon, Feb 12, 2018 at 3:08 PM, Kevin Kenny
    <kevin.b.kenny+...@gmail.com <mailto:kevin.b.kenny+...@gmail.com>>

        On Mon, Feb 12, 2018 at 12:55 PM, Kevin Broderick
        <k...@kevinbroderick.com <mailto:k...@kevinbroderick.com>> wrote:

            Please, please, please don't convert rural roads to tracks
            based on imagery alone unless it's incredibly clear (and
            that would exclude anything with forest cover).

            While many of them should definitely be unclassified, not
            residential, downgrading the main rural routes to tracks
            doesn't match local usage nor the functional topology of
            the road network in such places. There are a lot of USFS
            and BLM roads around here that are the only way to access
            significant areas, that commonly see normal passenger-car
            traffic and that can be traveled at reasonable speed in a
            sedan (or at 30+ MPH with a little ground clearance and
            driving skill),. Having these differentiated from true
            tracks (where even a stock 4x4 is likely going to be
            operating at 15 MPH or less) is incredibly helpful for
            routing and visual use of the map, and it's a lot easier
            to recognize what I'd call "areas of questionable data"
            when they haven't been aggressively armchair-mapped. Also,
            the smoothness key is really helpful for tracks and
            impossible to map from orthoimagery.

        Yes, yes, yes.

        In the rural areas that I can travel to readily, TIGER is
        downright hallucinatory (and there are few enough mappers that
        cleanup has been agonizingly slow). TIGER has roads in places
        where no road is, ever was, or even ever could be. (I've seen
        one going up a series of cliffs totalling about 2000 feet of
        ascent!) But even in 'leaves down' images, it's nearly
        impossible to see the forest roads, much less trace them, and
        there is definitely a wide variation in quality. Some of them
        are well-compacted sand and shale, that once they've been
        rolled in the spring, support driving at 30+ MPH. Others, I
        wouldn't bring my Subaru on. (Although I've been on a few of
        those in the ancient Ford Explorrer that the Subaru
        replaced.)  Some are gated, some, you simply have to decide
        for yourself that they're not drivable.

        The 'dirt roads' range from 'highway=path
        abandoned:highway=track smoothness=impassable' to
        'highway=tertiary surface=compacted smoothness=intermediate',
        with no way for an armchair mapper to tell among them.

        The old road maps that they used to give out at gas stations
        had, on many of these roads, "inquire locally for conditions,"
        which is still good advice. The signage may say, "LIMITED
        PURPOSE SEASONAL-USE ROAD: No maintenance November 1-April 15"
        - but in practice, they'll keep it open later in the Autumn
        unless the snow comes early, and when they open it in the
        spring depends on when the crews can get it clear - it could
        be weeks late if there's been a bad washout or rock slide.
        There's absolutely no way to tag and encode that sort of
        thing. Inquire locally for conditions.

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