OGF:Making realistic streetcar systems
Why a streetcar-net?
If you feel that an underground railway network (i.e. subway, metro, U-Bahn, ...) is too expensive for your town or your town is too small for it (approximately less than 1 000 000 inhabitants) - then a streetcar-system may be a better transportation than a bus-only system. Usually streetcar-systems are in towns of 80.000 inhabitants or more, but some smaller towns in Europe have some streetcar-lines as well. Also several small villages may have a streetcar-line to an important touristic place (e.g. to the beach or to the railway-station).
Many towns in with a metro network also have streetcar lines, for instance San Francisco, Boston and Philadelphia (USA), Milano (Italy), Lyon (France), Moscow and St. Petersburg (Russia), Berlin and Munich (Germany), Vienna (Austria), Prague (Czechia), Cairo (Egypt), Hongkong (China) and some other towns.
Many streetcar tracks have the same gauge as the railway in that country, usually the standard gauge of 1.435 m (4' and 8 1/2" inch) or a broader gauge like in Russia and some other countries. Other streetcar networks use narrower gauges like meter gauge. There are also other gauges - in the German towns of Braunschweig (Brunswick), Lübeck and Kiel the spur was 1.100 m. Maybe in your town there are an old and a new net of streetcar-lines with different spurs as drawn in Cordoba in Latina. Beside the obvious consequence - the size and capacity of the trams, there may be other reasons to pick a certain gauge. If the gauge matches that of the main railways, tram-trains are possible, while narrow gauges have the advantage of allowing narrower curves.
Radius of curves
Modern tramways need a radius of 25 m or more. Systems in 1.000 m spur and with short wagons with 2 axles may have curves down to 10 m in extrem cases (real world = Lisboa, Portugal). Clearly such curves allows only low speed. So please make your curves so wide, as far it is possible. To get smoother curves in real life streets are changed and houses are demolished - so as in real life you can do it at your map, if you create a new streetcar line.
Electification of previously horse drawn trams mainly occured 1892 to 1900. Thanks to Frank J. Sprague. Standard is direct current (DC) with roundabout 500 to 700 Volt. Only few horse-trams survived as touristic attraction or in very very lonely areas.
So it makes no sense at mapping, to set tags at your streetcar-lines as "electricified" and "overhead wire" and "volts" and what it may give. This is mostly redundant. (O.k. - some new trams p.e. in Bordeaux and Nizza / France have short pieces of underground electrification. As I know, there are the same problems with this solution as around 1900. If you will have such tracks without overhead-wire, you may tag this.)
System of line-numbers
In the beginning lines only have colours or a symbolic line signal as stars, crosses, letters and so on (see  at this webpage in german language]). In Germany first Hamburg in the year 1900 give the lines a number. If there are no more as roundabout 25 lines, you can give your lines a letter - but this is unusual for streetcars.
One number is eaual to the other. So in real life in many towns the system of numbering is more or less chaotic. But it is state of the art, to give the line-numbers a structure. As in Hamburg, Germany line numbers assigned in the year 1900 had a clear structure in the beginning - but some years later lines changed their way and this structure was lost more and more. In other towns it may be so in the same way.
But for the people in your town and the tourists it is helpful, to have a significant structure at the line numbers. So, if you like, you can have a numbering system. There are many possibilities. You could assign the lower numbers to the radial-lines in a clockwise order and then he higher numbers are for tangential lines. You could also reserve the numbers divisible by ten (10, 20 or 30, maybe even 0) for lines going in circles. In many cases the line numbers don't fully run in a sequence - often you have a gap. So you can have as example numbers 1 to 8, 10, 12 to 16, 19 to 22 or so. You may also want to group line numbers which are easy to memorize, e.g. 1, 11 and 21 may share most of there routes. Or you may have suffixes, instead of a line 3 there may be lines 3a and 3b. In the heart of the city often it is crowded traffic and therefore line did not end there. Most lines run through the town, so that two of the radial lines are connected to one longer line. In many cases the two ends don't need the same capacity, so often one end is served by an additional line to even that out.
If there is also a metro network in your city, then you can leave the lower numbers for the metro lines and let the line-numbers of the streetcar start with the next number divisible by 10. In real life in Paris /France the metro-lines are 1 to 14 and the bus line numbers started in the 20-ies - a system with good oversight. If your metro lines have letters, surely you can start the streetcar-lines with "1".
Older Streetcars do have short wagons with two axles not longer than 10m. Often these streetcars run with two trailers, so the streetcar train was roundabout 30 m long. Since 1900 are longer cars in use with four axles, later with one trailer. Today in Germany the longest streetcar-train allowed by law is 75 m.
So please think over it, what trains shall run at your system. However long this trains are, so long must be
- the place in the depots
- the place at the stops
- the platform at underground-stations (if you have such in your streetcar-system)
- the second track in a loop
- at lines with one track the short second track for passing of two trains
Service-tracks and depots
Your streetcars need service and a place in the night, sheltered from vandalism. This depots often are in the outer suburbs for several reasons
- in the heart of the city is no place among the existing buildings
- the price for the ground is cheaper outside
- normally the first rides go into the city to get to work and the last ride go back to sleep
How many depots you need? Calculate with the line in km (L) for both directions, the speed of your line in km/h (S) and how often will appear a train at the stops. 30 km (L) and 20 km/h (S) means, that a train needs 90 minutes for the tour of 15 km and back again 15 km. If there should be a service every 10 minutes, you need 9 trains for this line as minimum. If your peak-hours-service is every 5 minutes, logically you need 18 trains. So you can add all your streetcar-lines and on this addition put 10 or 20% to be at the safe side. A reserve is needed for trains to repair and special service for sport or cultural events.
On each track of your depot you can store one or two trains. If you will store two trains on one track, logically your depot must be longer as two of your streetcar-trains. Between two tracks should be some place for service - so four to six meters difference is necassary from track to track.
- one train on a depot track = more switches, but all trains can move independent
- two trains on a depot-track = fewer switches, but trains in the second row must wait that the track is free
One of the depots should have the main-service station for your streetcar-system. It is helpful to have railway-sidings there for the new streetcars coming from the wagon-factory. Depending on the gauge, the tracks may even be connected.
To serve your streetcar network, your depot has to connect with the outer end of the line. If other lines are also served from this depot, then it has to connect to the service tracks for that line. Anyway, it would even be better to connect your depot in both directions.
Not for all lines it is necessary to have an depot. Often other lines are connected with service-tracks, used only to get to and from the depot. There is a special tag for service-tracks: you use the normal tag for streetcar-lines and than add: "service = yard". These tracks on the map have a thinner grade.
If there is a short distance for the service-tracks, there are two tracks connecting the different lines. For longer distances one track may be enough, because in the morning the streetcars go out of the depot and at evening they come home. So this traffic moves only in one direction. Streetcar companies calculate: What is cheaper? Two switches or 500 m of a second track? Therefore at short distance there are two tracks and at longer distance one track and two switches.
Loops and triangles
At the end of a line or at important points at the line the trains terminate. This point of changing the direction can be constructed in different manners.
At the earlier times lines ended only with one switch to a short ending track. As it was usual, to set trailers after the electric car, at the end you change the direction in a complicated manoevre (see graphic). This in Hamburg / Germany was done til 1959 at one terminus of line # 5. But since around 1900 tramway-companies had begun to build loops (or in a few cases triangles) at the end of the lines for an changing the direction more easily.
Triangles need fewer space. The problem is, that the streetcar must reverse. Therefore triangles are usually only at places where a loop can not realisized. The stops can be at the place "A" to leave the train and "B" for getting in or the stops are at "C", so the train can turn without being disturbing by passengers.
Triangles can also be in the middle part of a line to turn the line as optional terminal, if there are any traffic-problems (demonstrations, accidents and so on).
The simplest methode to turn the direction is a loop. Loops are not only at the end of the line, but also at important places and to turn those trains, which do not run the whole line, but terminate before (may be for denser service in the peak hours). If more as one line terminates in a loop, then a second track there is helpful for spending the possibly different waiting line.
At branching of lines there might be a good place for a loop. The red tracks in the graphic show the tracks necessary to turn lines for the outer branches of the lines.
If there is no place, a loop can be around a block of houses. In other cases the loop lays in the middle of a greater square. For modern tramways please calculate a diameter of your loop of 50 m (radius = 25 m). Older systems or systems with 1.000 m gauge may have a diameter of 30 m.
Set a node on your track and tag it with (railway = tram_stop). For the name you can set a second tag. The name can be
- only the line-number or the line-numbers (p.e. 5 or 6.23 or 6 and 23 or 4-7 or 4 to 7)
- line number and name of the stop (p.e. 17 - Avenida Halcon or 3.15.16 - 67th S.)
- only the name of the stop - but then you can not follow the lines easily
If your name is too long, then it may not appear at the map or only at higher zoom-level. Therefore it is better to use short names for the stops (p.e. "Danton" instead of "Dantonstreet" or "56th S." instead of "56th Street / Chestnut Avenue" ). The name of a stop most is the name of a crossing street, an important place or an important building. Normally the name of the stop is not the name of the street which the line runs on.
Set a stop for both directions. You can set the stop before or after a crossing street. Both methodes have their fans. To set the stop after the crossing street means that the tram may continue its journey once the doors are closed without need to synchronize with the traffic lights.
If you have a branching of lines, set the stops at the tracks where both lines run. If you had a simple crossing of lines, set the stops for both lines near the junction for short passenger-ways - but not where you have the switches for the service-tracks. If you had a triangle of lines, preferably set three stops after the triangle. So the lines in the same direction stop at the same place.
The graphic shows the place of the stops given you drive on the right side. Otherwise, you must set the stops at the triangle at the opposite track.
To draw streetcar-lines
The tag is (railway = tram). If your line runs over a bridge, then also tag with (bridge = yes) and (layer = 1). If your line runs in a tunnel, then also tag with (tunnel = yes) and (layer = -1). Take layer 2 or -2, if there are other items with layers as 1 or -1, so the levels are clear and different. For service tracks please add the tag "service = yard".
If you tag a name to your tram-track (p.e. "lines 5 and 6"), this name will be visible in TopoMap-style at zoom-level 16 and in the histor-style in the zoom-levels 15 to 18, as well as in the standard-style. The ref tag of the tracks is not shown on the map.
One or two tracks?
It is better style to draw both tracks. This is the standard at OpenStreetMap too. To draw both tracks is important then, if the tracks run for the different directions in different streets (one-way street) as it in the real life often must be done in the heart of a town, where the streets are narrow.
Only if your line in the outer suburbs shall have only one track, then draw only that one. In this case do not forget short pieces with two tracks, where trains can pass each other. If your line there shall run every 10 minutes, you must have a passing place roundabout every 1.500 km (because both trains have only 5 minutes time for the way, if there are the next train from the other direction).
Drawing parallel lines
For drawing parallel lines, the editors have a special tool.
For "Podlatch 2":
- draw the first track of your line
- best work then is to change in zoom-level 18
- mark the line, to be doubled
- click the tool with 6 red points and two lines at bottom right
- you get a thin black line - move them near your first streetcar-track 3 m away (on screen roundabout 1 to 2 mm). There should be only few place between both lines.
- tag the thin line as (railway = tram)
- connect the new line with the old line
Tracks in the middle of the street
Since the beginning of the horse-tram till today often the streetcar-tracks lay in the middle of the street. The "broadness" of an OGF-street is only virtual, the street is only a line. So do not try to set a streetcar-line on the street-line. If you will later change someting at the steet or at the streetcar-line, you only get problems.
Better set the track (working in zoom-level 17 or better 18) parallel to the street in very short distance, but with own nodes. If your line here runs in both directions, set one track to the right and one to the left of the street.
Tracks with own right if way
Tracks can alos have their own right of way. So often the tracks lie in the middle of broad streets - may be with a row of trees aside. If you show this on the map, you draw two parallel streets - one for each direction. Many urbanisations from the 1880-ies are planned with such way for a streetcar-line in the new suburb. This "streetcar-street" does not need to be a primary or secondary street, but can be only a broad tertiary or residential street.
This soloution has one handicap: To reach the streetcar, the passengers must cross the street. To avoid this, the main street can be at one side of the streetcar-tracks and at the other side is only a small street in one direction for the local traffic.
At busy points of the streetcar-system (e.g. the main railway station) many lines come together. Here you can make more than two tracks to sort the lines by their destinations.
Tracks in a tunnel
Streetcar-lines may run in a tunnel, to avoid places with heavy traffic. At both sides of the tunnel you must think about a ramp. This ramp can be up to 100m long, where no crossing traffic is possible. If you do not want to construct a tunnel for the streetcar, you can construct a "flyover" for the most important line of the car-traffic.
Modern streetcars (p.e. in Germany in the cities of Cologne or Hannover, but in other countries too) in the inner city run some kilometres in tunnels and come to the surface in the outer suburbs. Sometimes - like in Bruxelles / Belgium - this is the first step for a metro-line. Here the stops are like metro-stations and it is necessary to tag a platform as a line with (railway = platform) at both sides of the tracks or in the middle of both tracks. Needed too then are entrances to the station as a node with (railway = subway_entrance).
To give this modern lines a better image, they are called in Germany not more streetcar, but "Stadtbahn" - means "Townrail". There is a gradual change from streetcar via light railway to a "heavy" metro-line / subway-line.
An example for streetcars in a tunnel in the OGF-world is in Gentofte (Latina) - see 17, -13.11742, 42.16618
Disused tracks and tracks in construction
You can tag disused tracks with (railway = disused). This may be a line without traffic, because this streetcar-line is substituted by bus or metro / subway, but the tracks are laying in the ground til now. On the map this is shown with a line with points.
Tracks in construction please tag with (railway = construction) and (construction = tram). On the map you see a line with small quadrates. Please draw both tracks here too.
To show your line in the OGF-wiki, you can set the line into a relation. All tracks of one line are to bound into one relation. But not the tracks of other lines. Each line is to put in an individual relation. Tracks, where run two or more lines are put in two or more relations. First work for this is, to take the scissor-tool and make pieces of tracks, where the lines separate.
That means, you create a new relation with (type = route), (route = tram) and (name = line-number or town-name and line-number) and (ref = shortcut of town and line-number).
Please tag one direction of each line with the role "forward" and the other direction as "backward". Add stations to the relation with the role "stop".
At the example of the graphic is set to four relations for four streetcar-lines
- to the red relation = tracks A, C, E and M
- to the orange relation = tracks H, G, F and M
- to the green relation = tracks B, C, D, G, J and K
- to the purple relation = tracks A, C, D, G, J and L
If you set at the OGF-wiki a link like "opengeofiction.net/relation/number of the relation" then your line you can be shown in the OGF-wiki as an orange line at the map. As example this is realisized at the Streetcar-system of of Aerwinya - please see as example there the lie 4 
Questions or comments? Things you would add or subtract? Feel free to share your thoughts on the Discussion page.