[talk-au] (LONG) Adelaide Highway Classification (was: Highway Classification Issues)

[Darrin Smith]

On Tue, 11 Mar 2008 00:46:20 +1030
Jack Burton <jack at saosce.com.au> wrote:
 
> > Going by how metroads are used in the relevant cities there are
> > roads of lower quality that some of the roads you are proposing to
> > eliminate labelled as turnk roads (southern end of metroad 3 in
> > sydney comes immediately to mind).
> > 
> > All the met-roads in other cities are about the cross-city nature of
> > things rather than the quality of the road. I would suggest the
> > only 2 "A" routes in Adelaide that don't fit this rule are the A22
> > and the A14. And yes the southern portion of the A15 past Norlunga
> > Centre is another case that's debatable.
> 
> A6 is not cross-city either, well, at least I didn't think it was
> until I saw your comments below about seeing A6 signposted in the
> Eastern suburbs.
> 
> Nor are A5, A7, A10 or A20, but they are all significant major
> arterial routes that I think everyone would agree should stay as
> highway=trunk.
> 
> A11 isn't cross-city either, but I'm still undecided on that one.

I had a though earlier tonight which gets very close to matching the
list you've been batting for (actually a couple less) and I think
might work:

A trunk route is any A Route with a reasonable amount (25% ? 5km ?) of
3-lanes carriageways.

This automatically includes A21, A5, A7, A13, A16, A20, A1 (both ends
because of the M1), A10.

Of course the 2 annoying ones it doesn't include are A3 and A17......
So yet another attempted definition falls down :)

> > However even though I don't think they deserve it, I think it's much
> > easier to define it as "all A roads" and be able to display that
> > than make a list that everyone keeps debating about.
> 
> If highway status is to determined solely by route class, why bother
> even having a highway tag -- you could render roads based on the ref
> tag instead. And perhaps, for an alternative rendering designed to
> highlight numbered routes, that's not such a bad idea.

This argument has been given for people arguing for a physical
definition of the highway (which has led to a physical description set
of tags being propose as Ian linked to I think).
 
> But my understanding was that the highway tag should describe what you
> will find when you get there - size/capacity (relative to the city
> it's in, of course), nature of junctions, usefulness for navigation,
> etc. - whilst the ref tag should describe where it fits into the
> national or state road numbering scheme.

See this is the thing. Size/Capacity and nature of junctions are only
really of interest to local travellers who often have that information
anyway. People travelling distances want something definite to hold on
to and the route numbering schemes provide that.. I know from trips to
a couple of other countries that a route numbering scheme is a godsend,
you don't care about the quality of the roads although you can
GENERALLY guess them from the route numbering 'level', but
navigationally they are essential.

Part of the issue here is that Adelaide is so easy to get around and
has so many long single name roads and no route numbering system till
now that it just seems like a pointless overlay to people who are
living in it, but speaking to a number of infrequent visitors to
Adelaide it's provided them with all the info they need.

> > > * Glen Osmond Road from the cnr of Greenhill Road to the Freeway
> > 
> > Part of this road isn't even an "A" Route, so does this suddenly
> > open us to defining other roads as trunk if we think they're busy
> > enough? 
> 
> It's the main route into the CBD for traffic arriving in Adelaide on
> the M1, including most traffic from the East Coast.

How much of that traffic actually makes it that far? large ammounts of
the traffic has already turned at the A3 or A17, and total VPD wise
Fullarton (A1 section) is carrying more traffic north of the junction
anyway. I'm very hesitant to include any road that's not an A route
because of exactly the navigation isssue, if we're telling people it's
a major navigational route but it doesn't even have a main route marker
on it????

> > > * The portion of Fullarton Road that has an A reference
> > 
> > This is one easily questioned for example, what makes it special/
> > sure the A1 goes along it but if Glen Osmond road is a trunk to
> > carry all the traffic into the city, what purpose does Fullarton
> > Road server except to carry a few wandered who didnt make the A17
> > turn past the city? 
> 
> Hmm, good point. The bit between Glen Osmond & Greenhill Roads (A1) is
> wide, heavily trafficed and generally trunk-like. As far as the A21
> portion goes, I guess I'm contradicting myself more than a little
> here, but I think it'd look a bit silly if the A21 didn't link up to
> itself as a trunk -- after all it's a circle route. 

Illustrating how arbitrary definitions complicate issues. I was tyring
to get across that from the Arkaba corner to the A21 there should be
*1* trunk route... not 2, that's a place where I agree with Stephen,
there would be too many too close together.

> > > * Salisbury Highway/John Rice Avenue
> > 
> > This is another one I though long and hard about trunking, after all
> > it's right next to Main North Road raelly (2km seperating them)...
> 
> Yes, I can see this one is debatable. On the one hand, it's just the
> main road through Salisbury & surrounds. On that basis, it'd only be a
> secondary. But on the other hand, it's kind of still at least the
> logical extension of South Road (ignoring the bit that got turned into
> the Expressway), linking it with Main North Road, which would make it
> a trunk.

Yes, I don't think Stephen realises the "Logical Extension of South
Road" factor in things. I think this one will become clearer as we sort
some of the other debatables out.

> It's also one of the slowest-moving main roads I've come
> across in Adelaide ;)

I used to think that (I live right next to it now) even up until we'd
ben living here a few months, then I realised it was a trick of
perception... MOST of the roads like Salisbury Highway (2 lanes
each way, 60kph, many turns) around the city are thinner and a much
higher density of traffic lights etc. It's 7km from Port Wakefield Road
to Salisbury itself and it rarely takes more then 7 or 8 minutes to do
it... It just SEEMS to take forever because the road is so boring
attention wise :)

> If you think primary is a better designation than trunk, I won't
> object. I think this one could go either way.

Lets hold that thought for a bit then :)

> > > I'm 50/50 on Payneham Road/Lower North East Road -- it's a road of
> > > importance (definitely at least primary), but not the main trunk
> > > route in the area (that would be North East Road).
> > 
> > How far away does a road have to be to be another 'trunk' road? Do
> > we now apply this there too?
> 
> Point taken. I'd be happy either way with this one.

Again this one MIGHT become clearer as we sort out some of the others.
 
> > > Likewise, with the A15 (Tapleys Hill Road/Brighton Rd/Lonsdale
> > > Rd/etc. etc.). Again, it's definitely a road of importance (at
> > > least primary), but particularly at the Southern end, I'd say not
> > > the main trunk route in the area (that would be Main South Road).
> > > For example, if you look at the area South of Seaford Road, Main
> > > South Road is currently tagged as primary, whereas Commercial
> > > Road (A15) is tagged as trunk, despite Main South Road being a
> > > much longer & wider road, with higher speed limits, greater
> > > traffic, more link-style access roads, less direct intersections,
> > > better signage and servicing more destinations.
> > 
> > Actually quality wise the only way Main South Road is better than
> > Commerical road to that point now is speed. Commerical road is by
> > far a higher quality road south of point where MSR becomes the B23.
> 
> That may be true once you get past Seaford Rise (it's been too long
> since I was last down that far), but I still think that at least going
> past Seaford & Seaford Rise, Main South Road is more trunk-like than
> Commercial Road.

That's actually the area I was talking about :) Once you pass there
Main South Road comes up trumps, I'd almost suggest that Commercial
Road south of Maslins (which is where the A15 signs End) wouldn't
qualify for anything above tertiary if it wasn't for the fact it's
straight on from the A15.

> And you're right -- looking at them, the type 6 roads are almost all
> what I would consider trunks. I wouldn't like to extend the analogy to
> type 7 roads though: there seem to be far more of them on the DoT maps
> than would be a reasonable number of primary roads for Adelaide.

Yup, in fact another definition comes to mind that's so VERY close to
what you are proposing:

trunk = A road that is both an "A" Route AND defined as a class 6 by
transport sa.

That gives us: A1, A3, A5, A7, A10, A11 (initial section??), A13, the
very busy part of A14, A15 only as far south as Beach Road, A16
(including the Victoria Road route but not the crappy bit around Port
Adelaide), A17, (NONE of the A18, the fly in the ointment?? can live
with it though), A20, A21 and the heavily trucked Cavan Road section of
A22.

I don't think it fits either of our opinions quite, but it's a kind of
middle ground where we can say "It is written" to any debaters :)

> The only other city I've spent much time with in OSM is Melbourne, and
> that does not appear to be the case there (although in country Vic
> there is a defined 1:1 mapping for MABC classified roads), mainly I
> guess because most of Melbourne's metro roads still use the old state
> (formerly metro) route numbers, which tell you next to nothing about
> the type of road you're on -- for example, both the S40 & the S83
> (both major cross-city routes) are in various segments motorways,
> trunk roads and primary roads, as appropriate for the physical
> characteristics of the road in each segment.

Yes Melbourne should be interesting as it alphanumerics at some point..
Looking forward to seeing how each of the eastern cities handle this
transition :)

And I think particularily the M83 example is poorly done, a turnk
shouldn't just end in an inner-city area, only place a trunk should
just end is at the edge of the outer suburbs, otherwise that person
driving along the trunk road is going to be asking "Where do I go next,
there's no TRUNK from here to get me where I'm going"

> I think the highway tag, as the tag that causes the biggest visible
> difference to a way on the map, probably needs to be a synthesis of
> all three factors, but if forced to choose a single one, it should
> probably be physical characteristics, since ref= is already giving us
> importance and lanes=, maxspeed= & toll= providing the key metrics
> for navigation.

Ok, I'll accept that as your opinion :) 

> > I am constantly annoyed by low quality maps which are useless for
> > navigational purposes because you can never easily determine the
> > routes you are following because they are not consistently labelled
> > a seperate colour.
> 
> Isn't that a rendering problem, though? Surely better solved by
> rendering a route number shield close to each side of an intersection
> at which a given route changes roads.

But dozens of near identical route representations with a mixture of
colour representations underneath doesn't help the person trying to
navigate via the road, especially if 1 route is changing colour (M83
again) quite a few times close together because even though it's a
through route it's physical characteristics happen to radically change
a few times, the person needs to know to KEEP GOING despite the changes
and a constant colour line emphasises that.

> > Again, nothing wrong with your point, but if you follow the thinking
> > then any A route can be dropped from trunk and any other route
> > can be upped to trunk and it suddenly becomes hard for people to
> > follow the map.
> 
> Only if they're particularly trying to follow the Axy, not if they're
> just trying to find the best way to get from point A to point B.

For someone unfamiliar with somewhere, following the Axy is ALWAYS
going to be easier than trying to follow a bunch of road names the are
completely unfamiliar with, as I said above, is this kind of map
detail for the people who live there every day and know physical
characteristics anyway? or for those unfamiliar with the area trying
to understand how to get around there.
 
> Yeah, not much we can do about that unfortunately, unless perhaps we
> consider Mt Barker as a little island of "urban" and the greater hills
> districts as a sea of "not urban". Again, I'd like to hear the
> perspective of someone who lives up that way.

It's more on the end of a Tongue of Urban really, sure all the towns
aren't quite joined up, but the inter-town length are smaller than the
towns in most cases :)
perhaps we need to tuck it in a bit then, or even say "Inside the
B34" + Mount Barker :)
 
> Agreed. I don't think incorporating the entire Barossa Valley into
> Adelaide metro makes much sense. I'm also a little puzzled as to why
> on that map Mount Compass (which isn't East of Adelaide at all) is
> classed as "Eastern", but Murray Bridge (much further East) isn't...

Who knows with the wonders of government :)
I work in a school and the number of illogical government definitions of
things I see....

> > > > 3) Primary Roads in City:
> >
> > B10, B19, B31 and B23 are all immediately in any definition of the
> > Metro area. Without my definition above we also have to include B33
> > and B34 meaning I can't count ;)
> 
> ...and presumably that I'm blind ;)

Or not quite as Route-obsessed as I am ;)

> > > Here's a start for the primary roads:
> > 
> > my comments: 
> <...>
> > > * A22 (Churchill Rd/Cavan Rd)
> > 
> > I'd almost suggest that if this wasn't a trunk it'd would be primary
> > for Cavan Road and secondary for the rest, it's just not that
> > important a road.
> 
> No objection here.

Of course by the 2nd proposed definition above we could end up with a
trunk/secondary case which is kinda appropriate :) The change at Grand
Junction Road is quite surprising.

> Morphett Street is a through route - it feeds one of the only three
> bridges across the Torrens between CBD & North Adelaide. Morphett
> St/Montefiore Rd/Jeffcott St could also be viewed as a logical
> extension of Torrens Road.

Ok, the crossing of the torrens argument is a good one, I'll go with
it :)

> Hutt St feeds George St, which admittedly is only useful if you live
> in that part of the inner South, so perhaps you're right on that one.

It does distribute some traffic of Glen Osmond Road so that counts for
something I guess, but it's as we've both said it just doesn't have the
long-haul potential...
Of course this gives us an interesting issue with the east end of
Grenfell, which is primary (which I agree with, especially now that
north terrace is getting squeezed). Not wanting primaries to 'just end'
in inner city areas also it's a tricky one...
 
> South Tce is not what it used to be. Didn't realise it was still
> marked primary. I agree secondary would be better.

Cool :D
 
> On the flip side, 3 of the 4 squares in the CBD are tagged primary,
> but Hindmarsh Square is tagged tertiary. Shouldn't it be upgraded at
> least to secondary?

4 of the 6, don't forget poor old hurtle down in the south west or
Wellington up in north Adelaide :)
The 3 in a row down morphett make sense as primaries because a primary
goes *around* them, and of course the inner portions of Vic Square
makes sense for the same reason. The outer portions of Hindmarsh and
Hurtle are just minor parking lanes so I raelly don't think they
deserve more than residential. And to be honest the city was one of
those secondary/tertiary cases I wanted to talk about, there's WAY to
many elevated roads at the these levels.. 
All those east-west roads in the southern section are not really
"major through routes" some of them you can't even drive across the
city. I'd actually suggest most of them south of Grote/Wakefield should
be tertiary. And East Terrace should be residential in the south.
Pirie and from are Fine as Secondaries however, being continuation of
incoming roads across the parklands. The rest in the north that are
currently secondary should probably be tertiary. And all those little
back rounds that are currently tertiary are all 'residential' really,
they're access roads.
I have to hold myself back every time at look at it :)

> > > * Those parts of Fullarton Road not marked as trunk
> > 
> If you're talking about the Southern end of Fullarton Road, I'd argue
> that it feeds Old Belair Road. If you mean the Northern end, I'll
> defer to your judgement, as I haven't been down it for years (for good
> reason :).

Lol, it's a little better these days with a  little bit of extra line
marking, but it's still a road to avoid unless you need it :)
 
> > > * Magill Road
> > 
> > Yup, as long as we continue it up into the hills to recognise it's a
> > significant through road (Old Nortin Summit Road is now the
> > preferred through route by road design).
> 
> Bizarre -- it used to be the opposite. But agreed.

yup, but they re-arrange the corner up the top in front of that hotel
whose name currently escapes me to force everyone down the 'Old' road.

I'd suggest if we use an "Inside the B34" city definition we extend
this right out to Lobethal and just beyond to the B34 for the
'navigational' and 'through route' point of view.
 
> > > * Walkleys Road/Sudholz Road/Darley Road
> > 
> > Definitely, but how far down? Newton Road? St Bernards Road?
> > Penfolds? This one is tricky because it again peters off at the
> > southern end but the northern end is definitley important in a
> > cross-city linking kind of way. I'd consider extending it all the
> > way to Greenhill Road (doglegging into Hallett Road) merely because
> > of the navigational factor.
> 
> Better map the southern end of it then :)

All the roads I'm talking about are on there, the Dog-Leg I mean is the
Penfolds/Kensington/Hallet. It kind of nicely complete the end of that
route. Of course if a few of the other primaries around there become
secondaries as we are suggesting and most of the current secondaries
fall back to tertiary, south of Penfolds could be secondary.
The whole area is another pretty highly ranked area that needs to be
toned down in general I think :D 

> > > * Sturt Road
> > 
> > Including Shepherds hill road all the way to blackwood round about.
> > (Then we face an interesting issue re Upper Sturt Road forming a
> > well used access path to southern suburbs from Crafers? primary?)
> 
> Well used, yes. But I don't think primary. Although, this will depend
> on whether we end up calling that part of the hills metro or not.

Are you talking about Upper Sturt or Shepherds hill here? 
I guess if Upper Sturt is secondary it'll stand out enough.
 
> > > * Flaxmill/Wheatsheaf Roads
> > 
> > Why? Sure it's a nice big road in parts, but it only links a few
> > suburbs. It's not that busy a road. It's only a level 8 road from
> > Transport SA's Point of View.
> 
> Links A15 with Panalatinga Rd - much quicker/easier driving than Beach
> Rd/Doctors Rd.

Perhaps east of Main South that reason works. I really don't think it
works west of there.

> > > * Seaford Road (between A15 and A13)
> > 
> > no, Griffiths Drive is the more important one in the region now,
> > linking right through to the A13 (good shortcut when the queue at
> > Main South Road corner is too long ;)
> 
> Okay, point taken. I would have argued this one in days gone by, but
> now that Seaford Road has a roundabout too, I'll just agree.

I would have agreed with you on this one 10 years ago before Seaford
Rise really got going, but it's shifted things south in that time.

> > > * Birdge Road (Pooraka)
> > 
> > This one had me thinking, I used to drive along it a lot and the
> > traffic levels are suprisingly low at the top end.
> > i think the section form Kings/McIntyre to Grand Junction is heavily
> > enough used to warrant primary, I'm still in 2 minds about the
> > northern section, it's almost just a small service road for those
> > few suburbs.
> 
> Agreed, since I've almost never used the Northern end of it, I'll
> defer to your judgement.

*growl* Now I have to decide for myself ;)
I think we'll leave it primary for now. It doesn't ruin the look
of things overly much.

> I'd feel a little uneasy tagging a metro road with "Highway" in its
> name as anything less than primary. Even the Chandler Hwy in Kew, Vic
> (to the best of my knowledge, the shortest "Highway" in Australia) is
> primary, although admittedly it carries part of route S21, and has
> its own freeway exit.

Ok, that's a fair enough reason :)

> > > * Old Mt Barker Rd/Old Princes Hwy (hills)
> > 
> > I balk at this one, it's neither a commuter route nor more than a
> > linker of adjacent towns who are too close to use freeway exits.
> > The B route system up there (B33 out through Stirling, B34 through
> > Hahndorf and Woodside and the B37 through Mount Barker) give us
> > primaries along all the main heavy routes anyway. The M1 just eats
> > up all the other heavy duty jobs.
> 
> Having looked again at the map, I'd agree, only tag the B ref'd
> segments as primary. May be moot anyway, if we decide that's not
> metro.

True, the 'Inside the B34' definition would mean we'd have to weigh
things up on a city scale though. Still if we come to the same
decision under both rural and city rules it makes things very
definite :)
  
> > > * Unley Road/Belair Road
> > 
> > This is a funny one, all the traffic goes up
> > unley/belair/blythewood/old belair/main road but I'd suggest from a
> > mapping point of view for a 'through route' for people/systems to
> > follow to use straight up belair road. And to extend this route
> > quite a distance south, where to stop is tricky because I've always
> > been of the opinion this should have been an A or B route all the
> > way to Goolwa, but that's just me. If we follow the rural pattern
> > outside of the city then at some point this route needs to drop to
> > 'secondary' since that's what it is in the rural section. So we
> > need to decide where to stop :) I'd suggest at least to Black Road.
> 
> I'd probably continue it as a primary to the corner of Upper Sturt
> Road, then have Main Road as a secondary, but you're right, it's a
> borderline one that could go either way from thereon in.
> 
> By the way, is Belair Road/Main Road still signposted as route T57?

Would you believe I was up there on Monday and never noticed (T routes
don't register high in my radar). If only the timing was slightly
better I would have been able to keep my eyes open :D
I would stronly object to stopping it anywhere short of blackwood round
about, even if we just end up with Sheps and Main Road secondary to
that point. If we don't we end up with quite a large suburban-ish area
up there with no primary roads at all!

This is is also why I'd seriously consider extending it down to the end
of Black Road and have Black Road as a Primary too, too many people
would be too far from any cross-city route.

And even if we stop it there we're going to have a large area of near
city countryside with no radial primary routes.

> > * Heaslip road and Angle Vale road from Heaslip Road to Galwer
> > 
> > A *VERY* heavy truck route and of course the target for replacement
> > by the northern expressway, but for the moment it's a very
> > signficant 2nd entry to the city from Gawler and Beyond.
> 
> Agreed. Maybe even the other side of Angle Vale Road too, as a link
> between Main North & Port Wakefiled Roads (although that's debatable).

I did think about this, but checking the transport SA traffic stats it
would appear around 2/3 of the traffic flows along the way I suggested.
I likewise was considering primary for the whole lot and that swayed
me. If you think it's a good idea from a navigation PoV I don't
disagree :)

> > * Grove Way - whole length
> > 
> > This is a very heavily trafficed road linking Salisbury and
> > Elizabeth to the Golden Grove & Modubry areas (and via Hancock Road
> > & Lower N.E.Rd suburbs south of the Torrens)
> > 
> > * Golden Grove Road to Old Golden Grove and possibly the road up
> > through snake gully to One Tree Hill and Gawler
> > 
> > The start of this one is easy, it's a major through road/arterial,
> > how far it follows along this path as primary I'm not sure since it
> > crosses into the almost rural area but Transport SA have not chosen
> > to put any B roads in the area..
> > 
> > * Black Top Road, this road links up to the above road higher up, it
> > links One Tree Hill and Para Wirra Consevation park to the city. If
> > we extend the above far enough up to intersect with this I think
> > this should be primary, if not it should probably fall back to
> > secondary. So this is a debatable one.
> 
> I'll take your word for it (I'm not strong on that part of town).

Ok, I'll think about these futher and look for another opinion from
someone. Unlike some of the other areas in the south there's a lot less
towns up this way so secondaries all around wouldn't necissarily be
unreasonable.

Perhaps we could make then Grove Way the termination end of the Golden
Grove Road Primary also and just go secondary after that.
> 
> > * Flagstaff Hill Road & continues
> > 
> > major north-south arterial in the area, perhaps continue it all the
> > way up Chandlers Hill Road to Clarendon? And beyond? (then we get
> > into rural teritory again) It has really replaced Chandlers Hill
> > road from South road (listed below) as the main route into this
> > area, carrying twice the traffic.
> 
> Is this Happy Valley Drive? If so, it never struck me as being that
> major. Mind you, it's some time since I was last down that way, so
> perhaps you're right.

Yup that's the one, It's the major north-south route east of
Main South Road/Pantalinga Road now, sucking nearly all the
north-south traffic off Chandlers Hill Road. 
 
> > * Kenihans Road/Chandlers Hill Road
> > 
> > This is a possible inclusion, forming another east-west link between
> > black road and sheriffs road, and looking at the Transport SA
> > traffic levels in the area this combination totally blitzes the
> > chandlers hill road to main south road path for traffic levels. not
> > sure if it quite qualifies for primary though.
> 
> Not quite sure either, but if we do, then we should make the whole of
> Chandlers Hill Road primary.

According to Transport SA only 3000 cars follow the 'old' Chandlers
Hill Road path (the segment between Kenihans and the right turn at the
south west corner of the reservoir is a good indicator of full-length
drivers) as I said above Happy Valley Drive has taken all the traffic.

> > (BTW just to make it clear I know all of Adelaide pretty well, 6
> > years of Taxi driving finishing 10 years ago and a healthy interest
> > in driving around adelaide just to look at the roads means I've
> > seen a LOT of it, just so you don't think Im totally making this
> > up :)
> 
> Good. Likewise. Some years ago I used to be a travelling salesman, so
> chances are we have driven many of the same roads, albeit for
> different purposes. So between the two of us we should be able to
> come up with a reasonably good model here (although I'd still like
> some help from somebody with a more intimate knowledge of the hills).

Excellent, lots of knowledge there too, good to hear. 

> > > * Oaklands Road/Daws Road/Springbank Road
> > 
> > This is a tricky one, including blythewood road it forms the next
> > significant east-west route down from Cross Road... another
> > borderline case..
> 
> Yes, borderline, but I'd say just the secondary side of the border ;)

Ok, I'll go with that. 
 
> > > * Kensington Road
> > 
> > This one could prove interesting, there are 2 signs on Portrush Road
> > showing the A6 going along here towards the city. However I'm still
> > waiting to see at least a couple more signs between West Terrace and
> > Portrush Road before I accept the A6 goes all the way through...
> > If we assume it doesn't for the moment, then yes it's a secondary :)
> 
> Well spotted. I agree that waiting makes sense. Especially since from
> the Western end the A6 seems to disappear when it hits the city.

Yup, that's what got me consfused when I saw those signs, it very
definitely ends at West Terrace by all the signage, in fact IIRC I
went to check and even all the signs pointing to Wakefield Street on
that corner do NOT show A6. I wonder if we'll end up with 2 A6's like
we have 2 A1's split by the City, that would be REALLY sad.
 
> > > * Nottage Terrace (Medindie)
> > > * Osmond Terrace (Norwood)
> > 
> > A tricky one, since Nottage forms the link from the A10 to the
> > western side of the A21 and carries nearly 30k vpd which is more
> > than quite a number of other roads around the city...  Certainly
> > the whole of the road BEYOND there is secondary territory.
> 
> I'd suggest that the Nottage beyond the A10 would only be tertiary.
> You may be right about between A10 and A1, but it seems a little
> irksome to have such a short segment of road tagged primary. I assume
> you're okay with demoting Osmond Tce.

Yup Im happy with a tertiary for everything past the A10, that makes
perfect sense to me.
It does carry 28,000 vpd on that tiny little section which by Adelaide
standards puts it above quite a few of other roads we've labeled as
primary (of course vpd isn't really a good indicator). It's also a
level 6 road from transport SA's point of view. but only for that tiny
little bit.
If we wanted to be dedantic in many sense we could argue the same way
against the last bit of Hampstead Road from Taunton Ave to North East
beind demonted to secondary. It's not really the A17 or A10, it's just
a link between them that apparently carries less traffic than Taunton
Avenue!! (BTw I'm not suggesting we do demote it, but it's the most
similar case road I could think of to get a comparable idea)

> > Now my own 'drop' additions:
> > 
> > * Chandlers Hill Road from main South Road to Kenihans Road (See
> > Above)
> 
> Not sure. I should probably drive it again (I don't recall it being so
> minor).

This is one that has changed in my driving lifetime for sure. When I
started driving back in the late 80's and worked for a pizza delivery
story up there, before Happy Valley Drive was built it was definitely
the major in the area. As Happy Valley Drive went in the traffic
slowly shifted across there so that that road is now mostly just
access to the immediate suburbs and the shops on Kenihans Road, which
is where the Mc Donalds went in (and you know how they attach
themselves to heavily trafficed roads).
I think we're not too many years away from seeing Kenihans straightened
to run into Chandlers Hill, perhaps even the whole diagonal take out
and sold for housing development.. 
I found some evidence online about
considering an upgrade of the Chandlers/Kenihans junction to a
roundabout or traffic signals, if that happens the alignment
construction will be interesting.
Of course a thought just occured, still mapping Chandlers as primary
could be argue for the same reason as taking the primary up old belair
road. It's the main through route even if not heavily trafficed.
So I guess from that point of view it works :) 

> > If it's a divided road with >= 2 lanes it's secondary if it's not
> > anything else. That covers just about every case of current primary
> > that should be secondary you listed above. :)
> 
> Sounds like a good rule. I can't think of any exceptions off the top
> of my head. And this seems to coincide nicely with the current
> "major/minor through route within a local area" on the Aust. Roads
> Tagging wiki page, for most examples I can think of in Adelaide.

Yup that was my thinking too, it doesn't cover every possible
secondary, but everyone one it does cover IS a secondary...
So we can put it down in a list of qualifications.

> Sounds good. Might be a good reason for me to finally bother to setup
> a wiki account too :). But can I suggest you make it an Adelaide page
> (rather than SA), since we're discussing metro areas here? (correct me
> if I am wrong, but I don't think any of us have a problem with the
> existing Aust. Roads tagging guidelines for non-urban roads).

Well I thought about an Adelaide Page and realise all the Rural section
for South Australia would say at this point was "Follow the General
Aussie Rural Rules" so if we had a page for each the SA page would be
pretty short and pointless, linking off to 2 other areas.

I've updated the page to reflect more of our discussion, hope I didn't
miss anything or get anything wrong :)

We're definitely making some progress here, our Primary+ and
not-primary at all distinction is getting pretty strong across the
board.

-- 

=b