# The Greta Effect

Bloomberg is reporting that Germany and Sweden are seeing a trend of reduced domestic air travel and greater rail usage. In Germany, intercontinental air traffic is up 2% year-over-year and international European traffic is down 2%, but domestic traffic has crashed in the last few months and is down 12% now. In Sweden, domestic air traffic is down 11%.

The Greta effect

Greta Thunberg famously crossed the Atlantic by sailboat to avoid personally contributing to greenhouse gas emissions. But she’s fairly practical about alternatives and said right out that she travels in such conditions to highlight how difficult complete decarbonization is. She is also very insistent on the fact that while changes in behavior are nice, collective political action is still needed.

Moreover, the young (as in, younger than me) Greens I meet in Germany are themselves practical as well. The more committed might take a train to France or Italy, but there’s not much interest in back-to-the-land 1960s communes, degrowth, or political revolution in the sense of the socialists and anarchists. Nor have I seen anti-nuclear sentiments recently – the one anti-nuclear sign I saw at the September 20th climate march, which had 100,000 people in attendance, was held by a pensioner and someone who looked 40, whereas the median age at the rally looked like 20.

It’s relatively easy to change travel behavior to avoid domestic flying in Germany as well as Sweden. Domestic rail travel pain in Germany means hourly Hamburg-Munich and Berlin-Stuttgart trains take 5:40 each. International rail travel pain means Berlin-Paris trains take 8:11 with a short transfer that I don’t trust DB or SNCF to meet. Domestic trains only get this long if many transfers are needed, in which case the main competition to the train is the car rather than the airplane, or if one needs to travel between Umeå (population 123,000) and central or southern Sweden. It’s thus likely that the shift in travel pattern reflects a change in consumer desires to avoid polluting – other explanations, such as the grounding of the 737 MAX, would equally affect domestic and European air travel.

Upcoming carbon taxation

Germany has been planning climate legislation for years, but the September 20th protest created a lot of pressure on the government to enact an aggressive package. A carbon tax will begin at €25/t-CO2 in 2021 and rise to €55/t by 2025, where the original plan was to only go up to €35/t. Sweden has had a carbon tax going back to 1991; starting in 2014, the Löfven cabinet has hiked the tax on industry to match the tax on transportation, both currently at €114/t. The effects on the German economy are to be seen, but in Sweden, economic growth has been healthy throughout this period, ahead of any not-newly-industrialized developed country save Australia (although the differences near the top are small).

In addition to the German carbon tax package, the EU is planning to levy a carbon tax on jet fuel for internal flights; so far, international emissions, including international aviation and shipping, are not subject to carbon tax. A leaked report suggests the EU is considering a tax of €330 per 1,000 liters of jet fuel, which corresponds to a hefty €130/t-CO2, the high figure coming from the fact that a ton of CO2 emitted at high altitude causes more global warming than one emitted at ground level. A very fuel-efficient plane like the A320neo consumes 2.25 liters per 100 seat-km on a 1,200 km flight, raising fares on a full flight by €9.06, which is not a game changer but is noticeable at low-cost carrier rates.

Planning for busier trains

The upshot is that demand for flights in Europe is likely to go down, shifting toward rail. The article linked above about the Greta effect says that DB expects its intercity rail traffic to double to 260 million passengers a year by 2040. The article makes no mention of which further investments in intercity rail DB is assuming, but a virtuous cycle is likely: higher ridership justifies more investment, and faster and more convenient trains attract higher ridership.

Of note, the weakness of international rail in Europe points to international connections as an investment priority. In Sweden, trains from Stockholm are fast toward Gothenburg and Malmö, averaging almost 140 km/h, and there are unfunded plans for high-speed rail connecting the three largest cities. However, Stockholm-Oslo trains are quite slow (about 6 hours for what looks like 500 km), even though Oslo is bigger than Gothenburg and Malmö and there are extensive economic and cultural connections between the Nordic countries. The Greens have called for Stockholm-Oslo high-speed rail, and the government should work with Norway on establishing such a line.

In Germany, the situation is different. London and Paris are vast cities, and Paris is within reasonable high-speed rail distance of most of Germany, with good connections on the French side and poor ones on the German one. Trains between Paris and Frankfurt take about 3:48, of which 1:47 is between Paris and Saarbrücken on the German side of the border, a distance of 380 km, and then 2:00 is between Saarbrücken and Frankfurt, a distance of about 200 km by rail and 160 by air. In Belgium, the existing high-speed line east of Brussels is compromised to the point of being slower between Brussels and Liège or Aachen than legacy lines like Stockholm-Gothenburg or London-Manchester.

The reason the map of the high-speed rail I think Germany should build is heavy on international connections is mostly that Europe is gradually building thicker international economic and social connections. However, a future with more expensive air travel and a consumer taste for greener ways of travel does not change the basic picture, and makes it more urgent.

(Map legend: blue is existing or under-construction lines, red is lines that are either in planning or not even in planning but should be built.)

Speed and capacity

DB’s forecast for 260 million annual rail travelers argues in favor of building more capacity. However, in no way does this conflict with building a dedicated high-speed rail network for Germany. On the contrary, the bypasses providing relief to congested lines are already planned to be high-speed: this was the case for the Tokaido Shinkansen and LGV Sud-Est decades ago, and this is now the case for HS2 and the planned Frankfurt-Mannheim express connection.

A largely dedicated network for high-speed passenger rail, with freight using the legacy lines, improves intercity rail reliability, allowing average speeds to rise to be closer to their theoretical technical maximums. Average speeds of 250 km/h on a few lines are plausible, as on Paris-Strasbourg or Madrid-Barcelona. Moreover, through-tunnels enabling intercity trains to run through Frankfurt and possibly Munich without reversing direction facilitate planning high-speed rail as a separate system. Timed connections with regional trains remain important, but critical trunks like Frankfurt-Cologne and Berlin-Hanover can run very frequently.

The schedule I tried writing for the above map in which domestic city pairs mostly run every half hour all day, interlining on a few trunks, assumes ridership of about 250 million. This is not the same as DB’s forecast of 260 million: this counts only high-speed rail riders, and assumes the average trip is 350 km long. To get from DB’s forecast to 87.5 billion p-km per year requires the virtuous cycle of higher ridership and more investment to work over time, but this is plausible given high levels of investment.

Green convenience

When Greta talks about systemic solutions, she understands that it’s important to make it easier to live a comfortable life without greenhouse gas emissions and harder to live one with high emissions. There are many aspects to green convenience: carbon-free electricity (largely achieved in Sweden but not in Germany), pedestrian- and bike-friendly streets, urban and periurban public transport, intercity and freight rail, passive solar design, urban density, carbon-free industrial power generation.

In every case, it’s important to seize upon any social, economic, or political trend that facilitates the green option. If people want to live in big central cities, then governments should make it easy to build housing there so that more people can enjoy the low-carbon wealth of Munich or Stockholm rather than live in cheap declining rural areas and drive. If people support solar power, then governments should leverage its political popularity and subsidize it to decarbonize electricity.

In the case of intercity transportation, a shift in taste toward intercity rail is a cause for celebration. Europe is full of intercity trunk lines ranging from ones that scream “build me now” no matter what (HS2, completing Berlin-Munich, etc.) to speculative ones. Any positive shift toward rail justifies adding ever more marginal intercity rail lines to the network. Perhaps if the network I mapped was justified before the Greta effect, after the Greta effect the most marginal parts of the network (like Stuttgart-Würzburg) are on more solid footing, while unmapped marginal lines like Munich-Prague or even Bremen-Oldenburg-Groningen become plausible.

But celebration does not mean idleness. Climate change is a systemic issue. The state must plan ahead, using the shift toward rail to plan further investments now so that they open in the 2020s and early 30s. This way, the rail network will meet near- and medium-term growth in demand, while stimulating long-term growth, to be satisfied through future investment, paid by taxes on the richer Germany of the 2030s. Good transit activists should take a page from Greta’s refusal to treat good news as grounds for letting up, and demand intensive investment in Europe’s rail network to ensure that green travel will be more convenient, featuring higher speeds rather than more sitting on luggage in the corridors of full trains.

# Fare Regulations

Public transportation companies may have the ability to raise fares arbitrarily based on market demands, for examples British buses outside London and American freight railroads. Or they may be subject to regulations capping the fare, for example Japanese railroads. Mixed systems exist as well, such as British rail fares. In Britain, the privatized, mostly deregulated approach is so commonly accepted that a Conservative recently called Labour dangerous socialists for proposing municipalizing bus systems, as in such socialist states as the US, Japan, Germany, etc. In reality, in the case of rail specifically (and perhaps buses as well), there’s a theoretical case with some empirical backing for why reasonable fare caps as in Japan can lead to more investment and more capacity, whereas wholly unregulated fares lead to hoarding and capacity cuts to create shortages.

The model

I’m stealing the economic model for this post from Paul Krugman, who used it to explain the California blackouts of 2000-1. The demand curve is inelastic: the demand is 1,000 units at $20/unit, decreasing to 900 units at$1,000/unit, at which point the curve goes flat. The supply curve is a constant $20/unit, but the market is oligopolistic (say, there are very high barriers to entry because building your own power plant is hard), and there are 5 producers, each with 200 units. If the price is regulated at$20/unit, each producer will supply 200 units. If the price is unregulated, then each producer alone gets an incentive to hold back production, since 100*1000 > 200*20, and then production will be curtailed to 900 units.

The model is simplified in a number of ways: real supply curves slope up; the part about demand going flat at 900 units is unrealistic and exists purely to avoid dealing with optimizing where at 800-something units each producer has an incentive to go back to producing more; capacity constraints involve escalating production costs rather than a God-given restriction on the number of suppliers and their capacity. But with all these caveats, it fits markets that have the following characteristics:

• There are steep barriers to entry, for example if large amounts of capital are required to enter (to build a power plant, set up a rail operating company, etc.).
• Demand is highly inelastic.
• Adding new capacity is expensive.

The issue of capacity

In rail, we can start plugging real numbers for both demand elasticity and the cost of new capacity.

In the above model the price elasticity is -0.0244 in the 900-1,000 units range, which is ridiculously inelastic, on purpose so as to highlight how the model works. TCRP Report 95 says the elasticity in a number of large cities studied is about -0.18, and a VTPI review in a mixture of cities and circumstances (peak vs. off-peak, bus vs. rail, etc.) asserts a short-term average of about -0.3. Unregulated fares will lead to supply reductions if the elasticity times the number of producers is more than -1 (or less than 1 if you flip signs); if no producer has <18% of the market, there will be supply restrictions under unregulated fares, just as a monopolist will hold back supply and raise fares if demand is inelastic.

The cost of new capacity of course depends on the line and the characteristics of competition between different railroads. It’s higher in Japan, where separate railroads run their own lines and trains, than in Britain, where different companies franchise to run trains on the same tracks. But even in Britain, getting a franchise requires a commitment to running service for many years. The significance of this is that the long-run public transport ridership elasticity with respect to fare is more elastic (VTPI recommends a range of -0.6 to -0.9), with a few estimates even going below -1.

For the purposes of this section, we do not distinguish capital from operating costs. Thus, the cost of new capacity is not given in units of capital costs, but in units of operating costs: if increasing service by 1% raises operating expenses by 2% counting the extra investment required, then we say the supply elasticity is 2. Note that supply curves slope up so the elasticity is always positive, but the elasticity can be below 1, for example if economies of scale are more important than the need to invest in new capacity.

Set the following variables: u is quantity of service, r is total revenue (thus, fare is r/u), c is total costs. The railroad is assumed profitable, so r > c. We are interested in the change in profit based on quantity of service, i.e.

$\frac{dr}{du} - \frac{dc}{du}.$

The important thing to note is that price controls keep dr/du higher in an oligopoly (but not in a competitive environment, like housing – a single landlord can’t meaningfully create a housing shortage). With price controls, we get

$\frac{dr}{du} = \frac{r}{u} = \mbox{constant fare}$

whereas without price controls, with elasticity $e_{d} < 0$, we get

$\frac{dr}{du} = \frac{r}{u} + \frac{r}{ue_{d}} = \frac{r}{u}(1 + 1/e_{d}).$

And likewise, with supply elasticity $e_{s} > 0$, we get

$\frac{dc}{du} = \frac{c}{ue_{s}}.$

Note, moreover, that price controls as construed in Japan let operating companies recover profits, letting them raise prices if they invest in more capacity, so that dr/du is actually higher than r/u.

The real world

I do not know to what extent the lack of fare regulation on many British trains contributes to capacity shortages. However, there is some evidence that the same situation is holding back investment in the United States, on Amtrak. Amtrak is a monopolist facing some fare regulations, for example congressional rules limiting the spread between the lowest and highest fares on a given train, but within its ability to set its own capacity in the medium run, it has relatively free hand, and in fact a strong incentive to maximize fares, in order to subsidize money-losing trains outside the Northeast Corridor.

Amtrak generally runs the trains it has on the Northeast Corridor, without explicitly holding back on capacity. However, this is in an environment with very low utilization rates. There are 20 Acela trainsets, but only 16 run in service at a given time, giving them the moniker “hangar queens.” There is no real interest within Amtrak at raising speed just enough to be able to run consistent service intervals, for example hourly with two trainsets coupled to form a 16-car train south of New York. Nor is there any interest in making small investments to permit such long trainsets to run – most Acela stops from New York to the south have platforms long or almost long enough for such trains, but the rest need to be lengthened, within right-of-way so that the cost is positive but low.

In the future, capacity cliffs may prove serious enough to stymie American passenger rail development. Right now the main obstacle are Amtrak itself and obstructive commuter railroads such as Metro-North, but assuming competent, profit-maximizing investment plans, it is not so expensive to invest in capacity and speed so as to permit around 4 long high-speed trains per hour north of New York (or even New Haven) and 6 south of it. But then the next few trains per hour require further bypasses, for example four-tracking most of the Providence Line. High supply elasticity – let’s say around 2 – is plausible. Then eventually a dedicated pathway to intercity trains through New York becomes necessary, raising supply elasticity even higher. In an environment with uncapped, profit-maximizing fares, a rational Amtrak management may well just keep what it has and jack up prices rather than build more capacity.

# High-Speed Rail in Small, Dense Countries

Four years ago I brought up the concept of the small, dense country to argue in favor of full electrification in Israel, Belgium, and the Netherlands. Right now I am going to dredge up this concept again, in the context of intercity trains. In a geographically small country, the value of very high speed is low, since trains do not have stretches of hundreds of kilometers over which 300 km/h has a big advantage over 200 km/h; if this country is dense, then furthermore there are likely to be significant cities are regular intervals, and stopping at them would eliminate whatever advantage high-speed rail had left.

Nonetheless, unlike with electrification, with high-speed rail there is a significant difference between Israel and the Low Countries. Israel does not have economic ties with its neighbors, even ones with which it does have diplomatic relationships, that are strong enough to justify international high-speed rail. Belgium and the Netherlands do – the high-speed rail they do have is already internationally-oriented – and their problem is that they have not quite completed their systems, leading to low average speeds.

The situation in Israel

Israel is a country of 20,000 square kilometers, with about 9 million people. Both figures exclude the entirety of the Territories, which are not served by intercity trains anyway, and have such geography that not even the most ardent annexationists propose to build any.

The country is long and narrow, and the maximum north-south distance is almost 500 km, but the cities at the ends are very small, and the population density in the South is exceptionally low. Eilat, at the southern tip of the country, is a city of 52,000, and is 170 km from the nearest Israeli city, Dimona. A low-speed line for freight may be appropriate for this geography, offering an alternative to the Suez Canal, but there is no real point in investing in high passenger rail speed. For purposes of fast intercity trains, the southern end of Israel is Beer Sheva, less than 100 km from Tel Aviv.

In the Galilee the situation is not quite as stark. The main barrier to intercity rail development is not low population density – on the contrary, the Galilee averages around 400 people per km^2, not counting the Golan Heights. Rather, the physical and urban geographies are formidable barriers: the mountainous topography forces all railroads that want to average reasonable speed to tunnel, and the cities are not aligned on linear corridors, nor are there very large agglomerations except Nazareth, which is about 100 km north of Tel Aviv. A low-speed rail network would be valuable, tunneling only under mountainous cities like Nazareth and Safed, but even 200 km/h in this region is a stretch, let alone 300. Thus, just as the southern limit of any fast intercity rail planning in Israel should be Beer Sheva, the northern limits should be Haifa and Nazareth.

The box formed by Haifa, Nazareth, Jerusalem, Tel Aviv, and Beer Sheva, less than 200 km on its long side, is not appropriate geography for high-speed rail. It is, however, perfect for medium-speed rail, topping at 160 or 200 km/h. The Tel Aviv-Jerusalem high-speed line, built because the legacy line is so curvy that it is substantially slower than a bus, only runs at 160 km/h for this reason – the distance along the railway between the two cities is 57 km and there’s an intermediate airport stop, so the incremental benefit of running faster is small. The Tel Aviv-Haifa line, built in stages in the 1930s and 50s, runs in the Coastal Plain and is largely straight, capable of 160 km/h or even faster. The Tel Aviv-Beer Sheva line is slower, but it too can be upgraded. In all of these cases, the target average speed is about 120 km/h or perhaps a little faster. A high-speed train would do better, but reducing trip times from 40 minutes to 30 just isn’t worth the expense of a new line.

Nazareth is the odd one out among the major cities, lacking a rail connection. This is for both geographical and sociopolitical reasons: it is on a hill, and it is Arab. Reaching Nazareth from the south is eminently possible, on a line branching from the Coastal Railway in the vicinity of Pardes Hanna, continuing northeast along Route 65 through Kafr Qara and Umm al-Fahm, and entering the city via Afula. Modern EMUs can climb the grades around Umm al-Fahm with little trouble, and only about 4 km of tunnel are required to reach Nazareth, including a mined underground station for the city. Continuing onward requires perhaps 8 km of tunnel.

However, so far Israel Railways has been reticent to enter city centers on tunnels or els. Instead, it serves cities on the periphery of their built-up areas or in freeway medians. It would require little tunneling to enter the center of Netanya or Rishon LeTsiyon, and none to enter that of Ashdod or Ashkelon. This is the result of incompetence, as well as some NIMBYism in the case of Rishon. Nonetheless, such short tunnels are the right choice for regional and intercity rail in those cities as well as in Nazareth, which poor as it is remains the center of Israel’s fourth largest urban agglomeration.

What if there is peace?

In Belgium and the Netherlands, there is 300 km/h high-speed rail, justified by international connections to France and Germany. What if Israel reaches a peace agreement with the Palestinians that thaws its relationships with the rest of the Arab world, justifying international connections to present-day enemy states like Syria and Lebanon as well as to cold friends like Jordan and Egypt?

The answer is that the Levant writ large, too, is a relatively small, dense area. The Palestinian Territories have even higher population density than Israel, as does Lebanon. Jordan and Syria, on the desert side of the mountains, are less dense, but if one drops their low-density areas just as one would drop Israel south of Beer Sheva, the box within which to build intercity trains is not particularly large either.

Amman is 72 km from Jerusalem; it’s an attractive target for a continuation of the Tel Aviv-Jerusalem railway at 160-200 km/h, the main difficulty being the grades down to and up from the Jordan Valley. Beirut and Damascus are both about 240 km from Tel Aviv on the most likely rail routes, via the coast up to Beirut and via Nazareth and Safed up to Damascus. The only connection at a truly compelling distance for 300 km/h rail is to Aleppo, which is not large enough and is unlikely to generate enough ridership across the language and political barrier to be worth it.

Egypt presents a more attractive case. Cairo is enormous, and there is a whole lot of nothing between it and the Gaza Strip, a perfect situation for high-speed rail. However, this is firmly in “we’ll cross that bridge when we get to it” territory, as none of the required construction really affects present-day Israeli intercity rail planning. It’s not like the Levantine Arab capitals, all of which lie along extensions of important domestic Israeli routes.

Integrated timed transfers

The Netherlands and Switzerland both have national rail networks based on the idea of an integrated timed transfer, in which trains from many destinations are designed to reach major nodes all at the same time, so that people can connect easily. In Switzerland, trains arrive at every major city just before :00 and :30 every hour and depart just after, and rail infrastructure construction is designed to enable trains to connect cities in integer multiples of half hours. For example, since trains connected Zurich and Basel with Bern in more than an hour, SBB built a 200 km/h line from Olten to Bern, shortening the trip time to just less than an hour to facilitate connections. Every half hour this line carries a burst of four trains in seven minutes in each direction, to ensure trains from many different destinations can connect at Bern at the right time.

I have argued against this approach in the context of Germany, proposing highspeed rail instead specifically on the grounds that Germany is a large country with many pairs of large cities 500 km apart. In the context of the Netherlands, the integrated timed transfer approach is far superior, which is why it is adopting this approach and refining it in ways that go beyond Switzerland’s decentralized planning. Belgium, too, had better adapt the Swiss and Dutch planning approach. What about Israel?

In Israel, timed transfers are essential to any intercity rail build-out. However, a fully integrated approach is more difficult, for three geographical and historical reasons. First, most intercity traffic flows through one two-track mainline, the Coastal Railway. Using advanced rail signaling to permit many trains to enter Tel Aviv at once is fine, but it would not be the everywhere-to-everywhere system of more polycentric countries like Switzerland.

Second, Israeli metro areas are really a mixture of the mostly-monocentric contiguous sprawl of France and the Anglosphere and the polycentric regions of distinct cities of the Netherlands and the German-speaking world. Jerusalem’s agglomeration is entirely Anglo-French in this typology, without significant independent cores, and Tel Aviv and Haifa both have substantial Anglo-French cores ringed by far less important secondary centers. The significant secondary centers around Tel Aviv and Haifa are edge cities within the built-up area that may be near a rail line, like Herzliya Pituah and the Kiryon, but are never independent town centers like the various Randstad and Rhine-Ruhr cities.

And third, Israel completely lacks the large railway terminals of Western countries that built their mainlines in the 19th century. Integrated pulses require one station track per branch coming out of the station, since the point of such timetables is to have trains from all branches arrive at the station at once. Within Germany there is criticism of the Stuttgart 21 project on the grounds that the new underground Stuttgart station will only have eight tracks, whereas there are about 14 planned branches coming out of the city.

So does this mean timed transfers are a bad idea? Absolutely not. Israel Railways must plan around timed transfers at junction stations like Lod, the closest thing the Tel Aviv region has to a German-style secondary core, as well as at future branch points. Entering secondary city centers like Netanya and Ashdod would involve tunnels and els, but more significantly to the national network, these would all be branches, and adding more branches to the mainline would require planning better transfers at the branch points and in the center.

Moreover, Israel still has significant intercity bus service, and most likely always will. Timed connections between buses and trains at outlying terminals like Ashdod are a must, and nationwide coordination of bus schedules to enable such connections is a must as well.

Intercity rail for a small, dense country

The situation in Israel – as in Belgium and the Netherlands – favors a different kind of rail development from that of larger countries like France and Japan. Short distances between major urban areas, frequent stops for intermediate cities, and cities that are not really located along easy lines call for the following design principles:

1. The maximum speed should be 160-200 km/h – lines should not be designed for higher speed if that requires more tunneling or bypassing existing mainlines, unless there is a compelling international link.
2. All trains should be electric, and run electric multiple units (EMUs) rather than locomotives, making use of EMUs’ fast acceleration to serve many stops.
3. Significant cities that do not have rail links or have circuitous links should get new lines, using short tunnels or viaducts if necessary to reach their centers.
4. Transfers at junction stations should be timed, as should transfers between buses and trains in cities with significant travel volumes to areas not served by the railway.
5. The state should coordinate timetables and fares at the national level and engage in nationwide integrated planning, since a change in one city can propagate on the schedule 100-200 km away.

In Israel, public transportation planners understand some of these points but not others. Rail planning is based on medium rather than high speed; there are some calls for a high-speed train to Eilat, but so far what I’ve seen is at least partly about freight rather than passengers. The state is electrifying most (though not all) of its rail network – but it’s buying electric locomotives as well as EMUs. New rail lines go in freeway medians and on tangents to built-up areas, as if they were 300 km/h lines, rather than low-speed regional lines for which if people have to drive 5 km they may as well drive the remaining 50 to their destination. Schedule coordination is a mess, especially when buses are involved.

Going forward, Israel should aim to have what the Netherlands has, and even more, since the Netherlands has not fully electrified its network, unlike Switzerland. Israel should aim for very high traffic density, connecting the major cities at a top speed of 160-200 km/h and average speed of about 120 km/h, with easy transfers to slightly slower regional lines and to buses. Its cities may not be Tokyo or Paris, but they’re large enough to generate heavy intercity traffic by public transportation, provided the rail network is there.

# High-Speed Rail for Germany and Capacity Issues

After feedback regarding the post I wrote last month about high-speed rail in Germany, here is an updated proposal:

Blue indicates lines that already exist or are under-construction, the latter category including Stuttgart-Ulm and Karlsruhe-Basel. Red indicates lines that are not; some are officially proposed, like Frankfurt-Mannheim and the Hanover-Hamburg-Bremen Y, others are not but should be.

Würzburg and capacity

The primary difference with the older map is that there’s more service to Würzburg, connecting it to Nuremberg, Frankfurt, and Stuttgart, in addition to the already existing line north toward Hamburg.

The reason for the added connections is not so much that they are by themselves great. Würzburg is not a large city. The through-services have some value, but the Stuttgart-Würzburg line saves travelers from Stuttgart or Zurich to Hamburg or Berlin half an hour, which is nice but not a big game-changer. The Frankfurt-Nuremberg connection is likewise of noticeable but not amazing value: Munich-Frankfurt and Munich-Cologne are shortened by about 15 minutes, and Nuremberg itself gets direct service to Frankfurt and points northwest but is only a medium-size city.

Rather, the most important reason for these connections is capacity. Today, the Frankfurt-Mannheim railway is the busiest in Germany; a high-speed line between the two cities is proposed for capacity more than for speed. However, under a more expansive high-speed rail program, this line would soon reach capacity as well. The demand for trains connecting Frankfurt to Basel, Zurich, and Munich in two hours is likely to be high, at least a train every half hour to each. Moreover, all of these cities would be connected with Cologne in three hours, and Stuttgart would be three hours from Berlin and three and a half from Hamburg. Raw demand may turn the Frankfurt-Mannheim trunk into the busiest high-speed rail trunk in the world off-peak, even ahead of the Tokaido Shinkansen and its six off-peak trains per hour in each direction. Moreover, this trunk would exhibit complex branching, in particular entering Frankfurt from either direction for through-service to either Cologne or Berlin and Hamburg.

The Würzburg connections change this situation. Trains from Stuttgart to Hamburg and Berlin do not need to pass through Mannheim and Frankfurt, and trains from Munich to Frankfurt do not need to pass through Stuttgart and Mannheim.

Half-hourly frequencies

Paris-Marseille fills about two trains per hour most of the day, Paris-Lyon counting both Part-Dieu and the airport fills around 1.5 trains per hour off-peak and 4 per hour at the peak. The TGV averages higher seat occupancy than the ICE, about 70% vs. 50%, because it varies service by time of day and has practically no seat turnover. It also runs trains with more seats, about 1,100 on a TGV Duplex vs. 900 on a single-level Velaro. This means that for the same ridership, Germany needs to run about two-thirds more frequency than France, which for the most part means matching the frequency France runs at the peak all day.

The largest metro region in Germany is the Rhine-Ruhr, with around 10 million people, not many fewer than Paris. It is polycentric, which normally works against a region – passengers are more likely to be traveling to a destination far from the central train station – but in this case works in favor of it, since the east-west network branches and makes stops at all major cities in the region. The second largest region is Berlin, with around 5 million people, twice as many as Lyon and three times as many as Marseille. Comparing this with Paris-Lyon and Paris-Marseille, an all-day frequency of six trains every hour is reasonable, two connecting Berlin to each of Cologne, Wuppertal-Dusseldorf, and the Ruhr proper from Dortmund to Duisburg.

In general, it’s best to think of this system as a series of city pairs each connected every half hour. The following list looks reasonable:

1. Hamburg-Berlin-Dresden-Prague
2. Berlin-Duisburg
3. Berlin-Dusseldorf-Amsterdam
4. Berlin-Cologne-Aachen-Brussels
5. Berlin-Bremen
6. Hamburg-Bremen
7. Berlin-Frankfurt-Saarbrücken-Paris
8. Berlin-Munich
9. Berlin-Stuttgart-Zurich
10. Berlin-Leipzig
11. Hamburg-Munich
12. Hamburg-Frankfurt-Basel
13. Amsterdam-Cologne-Frankfurt-Nuremberg-Munich
14. Duisburg-Cologne-Frankfurt-Basel
15. Duisburg-Cologne-Frankfurt-Stuttgart-Zurich
16. Cologne-Frankfurt-Leipzig-Dresden-Prague
17. Paris-Strasbourg-Karlsruhe-Munich
18. Munich-Vienna
19. Hamburg-Copenhagen

Not counting international tie-ins like Dresden-Prague, Munich-Vienna, or Aachen-Brussels, these lines total around 9,000 km with repetition, so the total service provision over 15 daily hours of full service is to be 540,000 train-km, maybe somewhat less if the weaker lines (especially Berlin-Leipzig) are served with single 200-meter trainsets rather than double trainsets. Filling seats at today’s rate, say with an average trip length of 350 km, requires ridership to be on the order of 250 million a year, which is about twice what it is today, and around two-thirds that of the Shinkansen. Germany has two-thirds Japan’s population, and the proposed network nearly doubles the average speed on a number of key city pairs, so at least on the level of a sanity check, this ridership level looks reasonable.

The half-hourly connections should be timed so that passengers have easy transfers on city pairs that do not have direct trains. For example, there are no direct Berlin-Karlsruhe-Basel or Hamburg-Stuttgart-Zurich trains, so the Berlin-Zurich and Hamburg-Basel trains should have a timed transfer at Fulda. A wrong-way timed connection between one of the Zurich-Stuttgart lines and the Munich-Stuttgart line toward Strasbourg should speed up Zurich-Munich travel, replacing the current slog through Austria.

Frankfurt, the center of the universe

Frankfurt is the most served station in this scheme, making it the key bottleneck: it has six connections in each direction, for a total of 12 trains per hour in each direction through the central tunnel. Berlin, in contrast, is the terminus on eight out of nine connections, so it only gets 10 trains per hour through the North-South Main Line (not counting Gesundbrunnen stub-ends), which has four tracks at any case.

The implication is that the Frankfurt tunnel should be used exclusively by high-speed trains, and regional trains should terminate on the surface. There may be capacity for a few regional connections in the tunnel, but unless they are extremely punctual, one delay would propagate to the entire country. An ICE network running largely on dedicated tracks would not have this problems – delays would be uncommon to begin with. In Berlin, the same is true in two tracks of the North-South Main Line; some regional trains can mix in the other two tracks, as well as on the express tracks of the Stadtbahn.

West of Frankfurt, eight trains per hour travel up the existing high-speed tracks to Cologne. This may be excessive, but six is not excessive given the sizes of the cities so connected. Passengers from all over central and southern Germany would have regular train access to Frankfurt itself as well as to the airport and some of the major cities of the Rhine-Ruhr. This is likely to be one of the two biggest long-distance bottlenecks, alongside Frankfurt-Mannheim, which is to get six trains per hour, two entering Frankfurt from the west to continue to Hamburg and four from the east to continue to Cologne.

Frankfurt’s position is not surprising given its geography. It’s near the center of western Germany’s north-south spine, right between the Rhine-Ruhr and the major cities of southern Germany and Switzerland. To its west lies Paris, two and a half hours away once a high-speed line to the French border opens. Berlin may be the larger city center, but it is located in Germany’s eastern margin, the capital of one historic state rooted in the east; Frankfurt is in a region that has always been denser and more economically developed, and high-speed rail is likely to strengthen its role as its distance from Paris and northern Switzerland is especially convenient by fast trains.

An environmental activist who saw the map asked why it was so thin in northwest Germany, mentioning a continuation of the line from Bremen to Oldenburg and even west to Groningen and Amsterdam as a possibility, as it has proven demand for intercity bus service. This connection may be prudent, I am not sure. My skepticism comes from the fact that northwest Germany does not have very big cities other than Hanover and Bremen, and medium-size cities like Oldenburg, Osnabrück, and Münster do not lie on convenient linear corridors.

Nonetheless, Oldenburg itself could be usefully served by a continuation of Berlin-Bremen or Hamburg-Bremen trains on legacy track. The same is true of a number of lines not indicated on the map, for example Hamburg-Kiel, or potentially some connections from Berlin and Hamburg to cities in Mecklenburg-Vorpommern branching off of the Berlin-Hamburg line. Moreover, among the four lines running on Frankfurt-Cologne, the one that does not run through to either Duisburg or the Netherlands could turn west to serve Aachen and maybe even continue to Brussels. Connections beyond Brussels are undesirable as Paris gets a faster direct link to Frankfurt, and London is a morass of delays due to border controls and Eurostar boarding slowness.

At the other end of the country, tie-ins to proposed tunnels across the Alps may be desirable. The problem is that these tunnels still leave the tracks with tens of kilometers of slow approaches that are not fixable without extensive tunneling. The air line distance between Zurich and Milan is 216 kilometers. The idea that a train could ever connect the two cities in an hour is complete fantasy, and even two hours is a stretch; Switzerland’s plans for the Ceneri and Zimmerberg base tunnels go down to about three hours. Farther east, the Brenner Base Tunnel’s northern portal is deceptively about a hundred kilometers by air from Munich, but half of that distance is across the Karwendel Alps and fast trains would require an entirely new route of complexity approaching that of the under-construction base tunnel.

Whither the Deutschlandtakt?

The Deutschlandtakt plan was meticulously developed over the years with the input of technical rail activists aiming to imitate Europe’s two best intercity rail networks, those of Switzerland and the Netherlands. Detailed maps of service in each region as well as nationwide for intercity trains are available, aiming to have timed connections between medium-speed trains wherever possible. But it is not the right way forward for a large country. With so many city pairs that high-speed trains could connect in two to four hours, Germany can and should build a network allowing trains to run largely on dedicated tracks, interlining so that most lines would see four to six trains per hour in each direction to ensure high utilization and return on investment.

At high service levels, trying to design lines to be utilized in bursts every half hour is not feasible or desirable. It’s more useful to space trains on intermediate connections like Berlin-Hanover to overlie to provide walk-up frequency, as high frequency is useful on short trips and encourages higher ridership. Moreover, key links like a tunnel through Frankfurt can’t really be used in bursts, as activists are pointing out in connection with Stuttgart 21. This is fine: Switzerland’s design methodology works well for a small country whose largest city would be Germany’s 16th largest, and Germany ought to see what France and Japan do that works and not just what Switzerland and the Netherlands do.

Is this feasible?

This high-speed plan does require high investment levels. But this is not outlandish. After fourteen years of stonewalling on climate change, with a flat fuel tax and more concern for closing nuclear plants than for closing coal plants, Angela Merkel has begun showing flexibility in face of massive climate change protests and announced a plan for a carbon tax.

Millennial and postmillennial Green voters lack the small-is-beautiful mentality of aging hippies. I did not see references to high-speed trains at the climate march a week ago (see selected signs on my Twitter feed), but I did see many calls for replacing cars with trains, and few small-is-beautiful signs, just one NIMBY sign against tall building and one anti-nuclear sign held by someone who looked 35-40 and someone who looked 60-70. Felix Thoma pointed out to me that as the Greens’ voter base is increasingly weighted in favor of educated millennials who travel often between cities, the next generation of the German center-left is likely to be warm to a national and international high-speed rail program.

The barrier, as always, is money. But Germany is not the United States. Costs here are higher than they should be, but they’re rarely outrageous – even Stuttgart 21 costs mostly in line with what one would expect such extensive regional rail tunnels to amount to. The core domestic network I’m proposing, that is excluding lines within Germany that are only useful for international connections like Stuttgart-Singen toward Zurich, adds 1,900 km of new high-speed rail, of which maybe 100 km is in tunnel. An investment of 60 billion euros would do it with some error margin.

A green future for Germany requires a network like the one I’m proposing. A green future can’t be one exclusively based around slow travel and return to the living standards of the early 20th century. It must, whenever possible, provide carbon-neutral alternatives to the usual habits that define modern prosperity. Trans-Atlantic travel may be too hard, but domestic travel within Germany is not, and neither is travel to adjacent countries: high-speed trains are an essential tool to permit people to travel conveniently between the major and medium-size cities of the country.

# The Future is not Retro

One faction of urbanists that I’ve sometimes found myself clashing with is people who assume that a greener, less auto-centric future will look something like the traditional small towns of the past. Strong Towns is the best example I know of of this tendency, arguing against high-rise urban redevelopment and in favor of urbanism that looks like pre-freeway Midwestern main streets. But this retro attitude to the future happens everywhere, and recently I’ve had to argue about this with the generally pro-modern Cap’n Transit and his take about the future of vacations. Even the push for light rail in a number of cities has connections with nostalgia for old streetcars, to the point that some American cities build mixed-traffic streetcars, such as Portland.

The future was not retro in the 1950s

The best analogy for a zero-emissions future is ironically what it seeks to undo: the history of suburbanization. In retrospect, we can view midcentury suburbanization as a physical expansion of built-up areas at lower density, at automobile scale. But at the time, it was not always viewed this way. Socially, the suburbs were supposed to be a return to rural virtues. The American patrician reformers who advocated for them consciously wanted to get rid of ethnic urban neighborhoods and their alien cultures. The German Christian democratic push for regional road and rail connections has the same social origin, just without the ethnic dimension – cities were dens of iniquity and sin.

At the same time, the suburbs, that future of the middle of the 20th century, were completely different from the mythologized 19th century past, before cities like New York and Berlin had grown so big. Most obviously, they were linked to urban jobs; the social forces that pushed for them were aware of that in real time, and sought transportation links precisely in order to permit access to urban jobs in what they hoped would be rural living.

But a number of other key differences are visible – for one, those suburbs were near the big cities of the early 20th century, and not in areas with demographic decline. In the United States, the Great Plains and Appalachia kept depopulating and the Deep South except Atlanta kept demographically stagnating. The growth in that era of interregional convergence happened in suburbs around New York, Chicago, and other big then-industrial cities, and in parts of what would soon be called the Sunbelt, namely Southern California, Texas, and Florida. In Germany, this history is more complicated, as the stagnating region that traditionalists had hoped to repopulate was Prussia and Posen, which were given to Poland at the end of the war and ethnically cleansed of their German populations. However, we can still see postwar shifts within West Germany toward suburbs of big cities like Munich and Frankfurt, while the Ruhr stagnated.

The future of transit-oriented development is not retro

People who dislike the auto-oriented form of cities can easily romanticize how cities looked before mass motorization. They’d have uniform missing middle built form in most of the US and UK, or uniform mid-rise in New York and Continental Europe. American YIMBYs in particular easily slip into romanticizing missing middle density and asking to replace single-family housing with duplexes and triplexes rather than with anything more substantial.

If you want to see what 21st-century TOD looks like, go to the richer parts of East Asia, especially Tokyo, which builds much more housing than Hong Kong and Singapore. The density in Tokyo is anything but uniform. There are clusters of high-rise buildings next to train stations, and lower density further away, even small single-family houses fronting narrow streets far enough from train stations that it’s not economical to redevelop them. It offends nostalgic Westerners; the future often does.

In the context of a growing city like New York or London, what this means is that the suburbs can expect to look spiky. There’s no point in turning, say, everything within two kilometers of Cockfosters (or the Little Neck LIRR station) into mid-rise apartments or even rowhouses. What’s the point? There’s a lot more demand 100 meters from the station than two kilometers away, enough that people pay the construction cost premium for the 20th floor 100 meters from the stations in preference to the third floor two kilometers away. The same is true for Paris – there’s no solution for its growth needs other than high-rises near RER stations and key Metro stations in the city as well as the suburbs, like the existing social housing complexes but with less space between buildings. It may offend people who associate high-rises with either the poor or recent high-skill immigrants, but again, the future often offends traditionalists.

The future of transportation is not retro

In countries that do not rigidly prevent urban housing growth the way the US does, the trend toward reurbanization is clear. Germany’s big cities are growing while everything else is shrinking save some suburbs in the richest regions, such as around Munich. Rural France keeps depopulating.

In this context, the modes of transportation of the future are rapid transit and high-speed rail. Rapid transit is preferable to buses and surface trains in most cities, because it serves spiky development better – the stations are spaced farther apart, which is fine because population density is not isotropic and neither is job density, and larger cities need the longer range that comes with the higher average speed of the subway or regional train over that of the tramway.

High-speed rail is likewise preferable to an everywhere-to-everywhere low-speed rail network like that of Switzerland. In a country with very large metro areas spaced 500 km or so apart, like the US, France, or Germany, connecting those growing city centers is of crucial importance, while nearby cities of 100,000 are of diminishing importance. Moreover, very big cities can be connected by trains so frequent that untimed transfers are viable. Already under the Deutschlandtakt plan, there will be 2.5 trains between Berlin and Hanover every hour, and if average speeds between Berlin and the Rhine-Ruhr were increased to be in line with those of the TGVs, demand would fill 4-6 trains per hour, enough to facilitate untimed transfers from connecting lines going north and south of Hanover. The Northeast Corridor has even more latent demand, given the huge size of New York.

The future of travel is not retro

The transportation network both follows and shapes travel patterns. Rapid transit is symbiotic with spiky TOD, and high-speed rail is symbiotic with extensive intercity travel.

The implication is that the future of holidays, too, is not retro. Vacation trips between major cities will become easier if countries that are not France and Japan build a dense network of high-speed lines akin to what France has done over the last 40 years and what Japan has done over the last 60. Many of those cities have thriving tourism economies, and these can expect to expand if there are fast trains connecting them to other cities within 300-1,000 kilometers.

Sometimes, these high-speed lines could serve romanticized tourist destinations. Niagara Falls lies between New York and Toronto, and could see expansion of visits, including day trips from Toronto and Buffalo and overnight stays from New York. The Riviera will surely see more travel once the much-delayed LGV PACA puts Nice four hours away from Paris by train rather than five and a half. Even the Black Forest might see an expansion of travel if people connect from high-speed trains from the rest of Germany to regional trains at Freiburg, going from the Rhine Valley up to the mountains; but even then, I expect a future Germany’s domestic tourism to be increasingly urban, probably involving the Rhine waterfront as well as the historic cities along the river.

But for the most part, tourist destinations designed around driving, like most American national parks as well as state parks like the Catskills, will shrink in importance in a zero-carbon future. It does not matter if they used to have rail access, as Glacier National Park did; the tourism of the leisure class of the early 20th century is not the same as that of the middle class of the middle of the 21st. Grand Canyon and Yellowstone are not the only pretty places in the world or even in the United States; the Hudson Valley and the entire Pacific Coast are pretty too, and do not require either driving or taking a hypothetical train line that, on the list of the United States’ top transportation priorities, would not crack the top 100. This will offend people whose idea of environmentalism is based on the priorities of turn-of-the-century patrician conservationists, but environmental science has moved on and the nature of the biggest ecological crisis facing humanity has changed.

The non-retro future is pretty cool

The theme of the future is that, just as the Industrial Revolution involved urbanization and rural depopulation, urban development patterns this century involve growth in the big metro areas and decline elsewhere and in traditional small towns. This is fine. The status anxieties of Basil Fawlty types who either can’t or won’t adapt to a world that has little use for their prejudices are not a serious public concern.

Already, people lead full lives in big global cities like New York and London without any of the trappings of what passed for normality in the middle of the 20th century, like a detached house with a yard and no racial minorities or working-class people within sight. The rest will adapt to this reality, just as early 20th century urbanites adapted to the reality of suburbanization a generation later.

It’s not even an imposition. It’s opportunity. People can live in high-quality housing with access to extensive social as well as job networks, and travel to many different places with different languages, flora and fauna, vistas, architecture, food, and local retail. Even in the same language zone, Northern and Southern Germany look completely different from each other, as do Paris and Southern France, or New England and Washington. Then outside the cities there are enough places walking distance from a commuter rail line or on the way on a high-speed line between two cities that people can if they’d like go somewhere and spend time out of sight of other people. There’s so much to do in a regime of green prosperity; the world merely awaits the enactment of policies that encourage such a future in lieu of one dominated by small-minded local interests who define themselves by how much they can pollute.

# The High-Speed Rail Germany Needs

I’ve argued in two previous posts that Germany needs to build a complete high-speed rail network, akin to what China, Japan, France, South Korea, and Spain have built. Here is the network that Germany should build in more detail:

The red lines denote high-speed lines, some legacy 250-280 km/h lines but most built to support 300-320 km/h, that are justifiable within the context of domestic travel. Some of these already exist, such as the Frankfurt-Cologne line and the majority of the Berlin-Munich line; Berlin-Hamburg is a legacy line upgraded to 230, currently tied with Frankfurt-Cologne for fastest average speed between two major cities in Germany. A handful of red lines are key legacy connections, i.e. Dresden-Leipzig and Dortmund-Duisburg. Some more detail on the red lines is available in Google Maps.

The blue lines denote high-speed lines, generally built to 300, that only make sense in an international context. The lines in France are the LGV Est and its short low-speed branch across the border to Saarbrücken. In Belgium the line preexists as well as HSL 3 and HSL 4, but is quite slow, averaging only 140 km/h from Brussels to Aachen thanks to a combination of a slow segment to Leuven and a speed-restricted western approach to Liege. In the Netherlands, Switzerland, Czechia, Austria, and Poland the lines are completely speculative, though in Czechia a high-speed line from Prague to Dresden is under study.

Update 8/19: here is another map of the same network, color-coded differently – red is proposed lines (most by me, a few officially), yellow is lines under construction, blue is existing lines, black is low-speed connections. Note that outside Berlin’s northern approaches, urban approaches are not colored black even if they’re slow.

Trip times

To compute trip times, I dusted off my train performance calculator, linked here. The parameters I used are those planned for the next-generation Velaro (“Velaro Novo“), i.e. a power-to-weight ratio of 20.7 kW/t and an initial acceleration rate of 0.65 m/s^2; the quadratic air resistance term is 0.000012, as any higher term would make it impossible to reach speeds already achieved in tests. On curves, the lateral acceleration in the horizontal plane is set at 2.09 m/s^2 on passenger-priority lines, mirroring what is achieved on Frankfurt-Cologne, and 1.7 elsewhere, accounting for lower superelevation.

These are aggressive assumptions and before running the code, I did not expect Berlin-Munich to be so fast. With intermediate stops at Erfurt, Nuremberg, and maybe also Ingolstadt, this city pair could be connected in 2.5 hours minus a few minutes for interchange time at the terminals. In general, all trip times printed on the map are a few minutes slower than what is achievable even with some schedule padding, corresponding to dwell times at major through-stations plus interchange at terminals. The upshot is that among the largest metro areas in Germany, the longest trips are Hamburg-Stuttgart at 3:30 minus change and Hamburg-Munich at 3:15 minus change; nothing else is longer than 3 hours.

The stopping pattern should be uniform. That is, every 320 km/h train between Berlin and Munich should stop exactly at Berlin Südkreuz, Erfurt, Nuremberg, and maybe Ingolstadt. If these trains skip Ingolstadt, it’s fine to run some 250 km/h trains part of the way, for example between Munich and Nuremberg and then northwest on legacy track to Würzburg and Frankfurt, with the Ingolstadt station added back. Similarly, from Hamburg south, every train should stop at Hanover, Göttingen, Kassel, and Fulda.

In certain cases, the stopping pattern should be decided based on whether trains can make a schedule in an exact number of quarter-hours. That is, if it turns out that Munich-Nuremberg with an intermediate stop in Ingolstadt takes around 42 minutes then the Ingolstadt stop should be kept; but if it takes 46 minutes, then Ingolstadt should be skipped, and instead of running in the depicted alignment, the line should stay near the Autobahn and bypass the city in order to be able to make it in less than 45 minutes. I think Ingolstadt can still be kept, but one place where the map is likely to be too optimistic is Stuttgart-Munich; Ulm may need to be skipped on the fastest trains, and slower trains should pick up extra stops so as to be 15 minutes slower.

Frequency and service planning

Today, the frequency on the major city pairs is hourly. Under the above map, it should be half-hourly, since the faster trip times will induce more ridership. As a sanity check, TGVs connect Paris with each of Lyon’s two stations hourly off-peak and twice an hour at the peak. Paris is somewhat larger than the entire Rhine-Ruhr, Lyon somewhat smaller than Stuttgart or Munich and somewhat larger than the Rhine-Neckar. But the ICE runs somewhat smaller trains and has lower occupancy as it runs trains on a consistent schedule all day, so matching the peak schedule on the TGV is defensible.

The upshot is that Berlin can probably be connected every 30 minutes to each of Hamburg, Munich, Frankfurt, Cologne, Düsseldorf, and the Ruhr proper. Frankfurt-Munich is likely to be every 30 minutes, as are Hamburg-Frankfurt and Hamburg-Munich. To further improve network connectivity, the schedule at Erfurt should be set in such a way that Hamburg-Munich and Berlin-Frankfurt trains are timed with a cross-platform transfer, regardless of the pulse anywhere else. A few connections to smaller cities should be hourly, like Berlin-Bremen (with a timed transfer at Hanover to Hamburg-Frankfurt or Hamburg-Munich), Leipzig-Munich, Leipzig-Frankfurt, and Frankfurt-Basel.

The loop track around Frankfurt is based on a real plan for mainline through-tracks at the station, currently in the early stages of construction. The near-Autobahn loop is not included, but such a connection, if done at-grade, could provide value by letting trains from Munich enter the station from the east and then continue northwest toward Cologne without reversing direction.

If the international connections are built as planned, then additional hourly and even more frequent connections can be attractive. Zurich-Stuttgart might well even support a train every half hour, going all the way to Frankfurt and thence to either Cologne or Berlin. Similarly, Berlin-Frankfurt-Paris could plausibly fill an hourly train if Frankfurt-Paris is cut to 2:30 via Saarbrücken, and maybe even if it takes three hours via Karlsruhe.

The one exception to this interconnected mesh is Fulda-Würzburg. The Hanover-Würzburg line was built as a single 280 km/h spine through West Germany with low-speed branches down to Frankfurt and Munich. Unfortunately, completing the Würzburg-Nuremberg segment has little value: Munich-Frankfurt would be almost as fast via Stuttgart, and Hamburg-Munich would be half an hour faster via Erfurt with not much more construction difficulty on Göttingen-Erfurt. Fulda-Würzburg should thus be a shuttle with timed transfers at Fulda, potentially continuing further south at lower speed to serve smaller markets in Bavaria.

Cost

The domestic network depicted on the map is 1,300 km long, not counting existing or under-construction lines. Some lines require tunneling, like Erfurt-Fulda-Frankfurt, but most do not; the heaviest lifting has already been done, including between Erfurt and Nuremberg and around Stuttgart for Stuttgart 21 and the under-construction high-speed line to Ulm. I doubt 100 km of tunnel are necessary for this network; for comparison, Hanover-Würzburg alone has 120 km of tunnel, as the line has very wide curve radii to support both high-speed passenger rail and low-speed freight without too much superelevation. The cost should be on the order of 30-40 billion euros.

The international network is more complex. Berlin-Prague is easy on the German side and even across the border, and the only real problems are on the Czech side, especially as Czech planners insist on serving Usti on the way with a city center station. But Stuttgart-Zurich is a world of pain, and Frankfurt-Saarbrücken may require some tunneling through rolling terrain as well, especially around Saarbrücken itself.

Even with the international lines added in, the German share of the cost should not be too onerous. Getting everything in less than 50 billion euros should not be hard, even with some compromises with local NIMBYs. Even on an aggressive schedule aiming for completion by 2030, it’s affordable in a country where the budget surplus in 2018 was €58 billion across all levels of government and where there are signs of impending recession rather than inflation.

With its mesh of medium-size cities all over the country following plausible lines, Germany is well-placed to have the largest high-speed rail network in Europe. It has the ability to combine the precise scheduling and connections of Switzerland and the Netherlands with the high point-to-point speeds of France and Spain, creating a system that obsoletes domestic flights and competes well with cars and intercity buses. The government can implement this; all it takes is the political will to invest in a green future.

# Why You Should Complete High-Speed Lines

Some countries build complete high-speed rail networks, on which one can travel between cities almost entirely at high speed, such as France, Japan, and China. Others build partial networks, mixing low- and high-speed travel, such as Germany. The planning lingo in the latter is “strategic bypass” or “strategic connection.” And yet, there is nothing strategic about most mixed lines. If a line between two cities is partly high-speed and partly low-speed, it is usually strategic to complete the high-speed line and provide fast travel – the benefits will exceed those of having built the original high-speed partial segment. Since Germany’s rail network largely consists of such mixed lines, the benefits of transitioning to full high-speed rail here are large.

The arguments I’m about to present are not entirely new. To some extent, I discussed an analog years ago when arguing that in the presence of a complete high-speed line, the benefits of building further extensions are large; this post is a generalization of what I wrote in 2013. Then, a few months ago, I blogged about positive and negative interactions. I didn’t discuss high-speed rail, but the effect of travel time on ridership is such that different segments of the same line positively interact.

The upshot is that once the basics of a high-speed rail networks are in place, the benefit-cost ratio of further extensions is high. In a country with no such network, the first line or segments may look daunting, such as India or the UK, but once it’s there, the economics of the rest tend to fall into place. It takes a while for returns to diminish below the point of economic viability.

A toy model

Take a low-speed rail line:

Now build a high-speed line parallel to half of it and connect it with the remaining half:

You will have reduced trip time from 4 hours to 3 hours. This has substantial benefits in ridership and convenience. But then you can go all the way and make the entire line fast:

Are there diminishing returns?

No.

The benefits of reducing travel time per unit of absolute amount of time saved always increase in speed; they never decrease. The gravity model holds that ridership follows an inverse square law in total cost, including ticket fare and the passengers’ value of time, which time includes access and egress time. Reducing in-vehicle travel time by a fixed amount, say an hour, increases ridership more if the initial travel time is already lower.

This is on top of reductions in operating costs coming from higher speed. Trains on high-speed track consume less electricity than on legacy track, because they cruise at a constant speed, and because head-end power demand scales with time rather than distance traveled. Crew wages per kilometer are lower on faster trains. And the cost of rolling stock procurement and maintenance is spread across a longer distance if the same train is run more kilometers per year. In the toy model, there are actually increasing returns coming from rolling stock costs: upgrading half the line to high speed requires running an expensive high-speed train on the entire line, whereas completing the high-speed line does not require increasing the cost per unit of rolling stock.

Diminishing returns do occur, but only in the context of an increase in top speed, not in that of speeding up slow segments to match the top speed of faster segments. In that context, benefits do diminish and costs do rise, but that is not the same as completing high-speed lines.

As the maximum speed is increased from 160 to 200 km/h, the train speeds up from 22.5 seconds per kilometer to 18. To provide the same increase further, that is to reduce the time taken to traverse a kilometer by a further 4.5 seconds to 13.5, the speed must increase to 266.67 km/h. To provide the same 4.5-second increase once more, the speed must increase to 400. Curve radius is proportional to the square of speed, so these increases in speed must be accompanied by much more exacting track geometry. Tunnels may well be unavoidable at the higher speeds in topography that could accommodate 200-250 entirely at-grade.

What’s more, operating costs rise too as top speed increases. The electricity consumption on a 300 km/h cruise is lower than on a legacy line on which trains transition back and forth between 200 and 100 and all speeds in between, but the electricity consumption on a 350 km/h cruise is definitely higher than on a 250 km/h cruise.

However, what is relevant to the decision of what standards to build a line to is not relevant to the decision of how far to extend this standard. Once a 300 km/h segment has been built, with a dedicated fleet of trains that cost 30 million per 200-meter set, the returns to upgrading the entire segment the train runs on are higher than those of just building the initial segment.

Can some strategic segments be easier to build than others?

Yes, but only in one specific situation: that of an urban area. The toy model says nothing of construction costs – in effect, it assumes the cost of making the first 200 km fast is the same as that of making the next 200 km fast. In reality, different areas may have different construction challenges, making some parts easier to build than others.

However, if the construction challenge is mountainous topography, then the higher cost of mountain tunnels balance out the greater benefit of fast trains across mountains. The reason is that in practice, legacy rail lines are faster in flat terrain than in the mountains, where past construction compromises led to sharp curves.

This situation is different in urban areas. In urban areas as in the mountains, costs are higher – land acquisition is difficult, and tunnels may be required in areas where the alternative is buying out entire city blocks. But unlike in the mountains, the existing rail line may well be reasonably straight, permitting average speeds in the 120 km/h area rather than the 70 km/h area. In that case, it may be advisable to postpone construction until later, or even keep the legacy alignment.

One example is the Ruhr area. The tracks between Dortmund and Duisburg are not high-speed rail – the fastest trains do the trip in about 34 minutes, an average speed of about 95 km/h. Speeding them up by a few minutes is feasible, but going much below 30 minutes is not. Thus, even if there is a 300 km/h line from Dortmund to points east, the returns to the same speedup between Dortmund and Duisburg are low. (Besides which, Dortmund is the largest city in the Ruhr, and the second largest, Essen, in the middle between Dortmund and Duisburg.)

Another is Connecticut. East of New Haven, there is relatively little urban development, and constructing a 300-360 km/h line roughly along the right-of-way of I-95 poses few challenges. West of New Haven, such construction would require extensive tunneling and elevated construction – and the legacy line is actually somewhat less curvy, it’s just slower because of poor timetable coordination between Amtrak’s intercity trains and Metro-North’s regional trains. While the returns to building 250-300 km/h bypasses around the line’s slowest points in southwestern Connecticut remain high enough to justify the project, they’re lower than those in southeastern Connecticut.

The situation in Germany

On the following map, black denotes legacy lines and red denotes purpose-built 300 km/h high-speed lines:

The longer red segment, through Erfurt, is the more challenging one, including long tunnels through the mountains between Thuringia and Bavaria. The complexity and cost of construction led to extensive media controversy. In particular, the choice of the route through Erfurt came about due to Thuringia’s demands that it serve its capital rather than smaller cities; DB’s preference would have been to build a more direct Leipzig-Nuremberg route, which would have had shorter tunnels as the mountains in eastern Thuringia are lower and thinner.

Since then, a lot of water has passed under the bridge. The route opened at the end of 2017 and cut travel time from 6 hours to 4, bypassing the slowest mountain segment, and is considered a success now. In the North German Plain, the trains mostly cruise at 200 km/h, and trains traverse the 163.6 km between Berlin and Halle in 1:09-1:11, an average speed of 140 km/h.

Nonetheless, the benefits of painting the entire map red, roughly from the city limits of Berlin to those of Munich, are considerable. The North German Plain’s flat topography enables trains to average 140 km/h, but also means that building a high-speed line would be cheap – around 137 km of new-build line would be needed, all at-grade, at a cost of about €2.5 billion, which would cut about half an hour from the trip time. In Bavaria, the topography is rougher and consequently the legacy trains’ average speed is lower, but nonetheless, high-speed rail can be built with cut-and-fill, using 4% grades as on the Cologne-Frankfurt line.

I’m uncertain about the exact travel time benefits of such a high-speed line. I put a route through my train performance calculator and got about 2.5 hours with intermediate stops at Südkreuz, Erfurt, Nuremberg, and possibly Ingolstadt (skipping Ingolstadt saves 3 minutes plus the dwell time), using the performance characteristics of the next-generation Velaro. But I’m worried that my speed zones are too aggressive and that the schedule should perhaps accommodate TGVs coming from Paris via Frankfurt, so I won’t commit to 2:30; however, 2:45-2:50 should be doable, even with some unforeseen political compromises.

But even with less optimistic assumptions about trip times, Germany should do it. If it was justifiable to spend €10 billion on reducing trip times from 6 hours to just under 4, it should be justifiable to spend around half that amount on reducing trip times by another hour and change.

# Deutschlandtakt and Country Size

Does the absolute size of a country matter for public transport planning? Usually it does not – construction costs do not seem to be sensitive to absolute size, and the basics of rail planning do not either. That Europe’s most intensely used mainline rail networks are those of Switzerland and the Netherlands, two geographically small countries, is not really about the inherent benefits of small size, but about the fact that most countries in Europe are small, so we should expect the very best as well as the very worst to be small.

But now Germany is copying Swiss and Dutch ideas of nationally integrated rail planning, in a way that showcases where size does matter. For decades Switzerland has had a national clockface schedule in which all trains are coordinated for maximum convenience of interchange between trains at key stations. For example, at Zurich, trains regularly arrive just before :00 and :30 every hour and leave just after, so passengers can connect with minimum wait. Germany is planning to implement the same scheme by 2030 but on a much bigger scale, dubbed Deutschlandtakt. This plan is for the most part good, but has some serious problems that come from overlearning from small countries rather than from similar-size France.

In accordance with best industry practices, there is integration of infrastructure and timetable planning. I encourage readers to go to the Ministry of Transport (BMVI) and look at some line maps – there are links to line maps by region as well as a national map for intercity trains. The intercity train map is especially instructive when it comes to scale-variance: it features multihour trips that would be a lot shorter if Germany made a serious attempt to build high-speed rail like France.

Before I go on and give details, I want to make a caveat: Germany is not the United States. BMVI makes a lot of errors in planning and Deutsche Bahn is plagued by delays; these are still basically professional organizations, unlike the American amateur hour of federal and state transportation departments, Amtrak, and sundry officials who are not even aware Germany has regional trains. As in London and Paris, the decisions here are defensible, just often incorrect.

Run as fast as necessary

Switzerland has no high-speed rail. It plans rail infrastructure using the maxim, run trains as fast as necessary, not as fast as possible. Zurich, Basel, and Bern are around 100 km from one another by rail, so the federal government invested in speeding up the trains so as to serve each city pair in just less than an hour. At the time of this writing, Zurich-Bern is 56 minutes one-way and the other two pairs are 53 each. Trains run twice an hour, leaving each of these three cities a little after :00 and :30 and and arriving a little before, enabling passengers to connect to onward trains nationwide.

There is little benefit in speeding up Switzerland’s domestic trains further. If SBB increases the average speed to 140 km/h, comparable to the fastest legacy lines in Sweden and Britain, it will be able to reduce trip times to about 42 minutes. Direct passengers would benefit from faster trips, but interchange passengers would simply trade 10 minutes on a moving train for 10 minutes waiting for a connection. Moreover, drivers would trade 10 minutes working on a moving train for 10 minutes of turnaround, and the equipment itself would simply idle 10 minutes longer as well, and thus there would not be any savings in operating costs. A speedup can only fit into the national takt schedule if trains connect each city pair in just less than half an hour, but that would require average speeds near the high end of European high-speed rail, which are only achieved with hundreds of kilometers of nonstop 300 km/h running.

Instead of investing in high-speed rail like France, Switzerland incrementally invests in various interregional and intercity rail connections in order to improve the national takt. To oversimplify a complex situation, if a city pair is connected in 1:10, Switzerland will invest in reducing it to 55 minutes, in order to allow trains to fit into the hourly takt. This may involve high average speeds, depending on the length of the link. Bern is farther from Zurich and Basel than Zurich and Basel are from each other, so in 1996-2004, SBB built a 200 km/h line between Bern and Olten; it has more than 200 trains per day of various speed classes, so in 2007 it became the first railroad in the world to be equipped with ETCS Level 2 signaling.

With this systemwide thinking, Switzerland has built Europe’s strongest rail network by passenger traffic density, punctuality, and mode share. It is this approach that Germany seeks to imitate. Thus, the Deutschlandtakt sets up control cities served by trains on a clockface schedule every 30 minutes or every hour. For example, Erfurt is to have four trains per hour, two arriving just before :30 and leaving just after and two arriving just before :00 and leaving just after; passengers can transfer in all directions, going north toward Berlin via either Leipzig or Halle, south toward Munich, or west toward Frankfurt.

Flight-level zero airlines

Richard Mlynarik likes to mock the idea of high-speed rail as conceived in California as a flight-level zero airline. The mockery is about a bunch of features that imitate airlines even when they are inappropriate for trains. The TGV network has many flight-level zero airline features: tickets are sold using an opaque yield management system; trains mostly run nonstop between cities, so for example Paris-Marseille trains do not stop at Lyon and Paris-Lyon trains do not continue to Marseille; frequency is haphazard; transfers to regional trains are sporadic, and occasionally (as at Nice) TGVs are timed to just miss regional connections.

And yet, with all of these bad features, SNCF has higher long-distance ridership than DB, because at the end of the day the TGVs connect most major French cities to Paris at an average speed in the 200-250 km/h range, whereas the fastest German intercity trains average about 170 and most are in the 120-150 range. The ICE network in Germany is not conceived as complete lines between pairs of cities, but rather as a series of bypasses around bottlenecks or slow sections, some with a maximum speed of 250 and some with a maximum speed of 300. For example, between Berlin and Munich, only the segments between Ingolstadt and Nuremberg and between Halle and north of Bamberg are on new 300 km/h lines, and the rest are on upgraded legacy track.

Even though the maximum speed on some connections in Germany is the same as in France, there are long slow segments on urban approaches, even in cities with ample space for bypass tracks, like Berlin. The LGV Sud-Est diverges from the classical line 9 kilometers outside Paris and permits 270 km/h 20 kilometers out; on its way between Paris and Lyon, the TGV spends practically the entire way running at 270-300 km/h. No high-speed lines get this close to Berlin or Munich, even though in both cities, the built-up urban area gives way to farms within 15-20 kilometers of the train station.

The importance of absolute size

Switzerland and the Netherlands make do with very little high-speed rail. Large-scale speedups are of limited use in both countries, Switzerland because of the difficulty of getting Zurich-Basel trip times below half an hour and the Netherlands because all of its major cities are within regional rail distance of one another.

But Germany is much bigger. Today, ICE trains go between Berlin and Munich, a distance of about 600 kilometers, in just less than four hours. The Deutschlandtakt plan calls for a few minutes’ speedup to 3:49. At TGV speed, trains would run about an hour faster, which would fit well with timed transfers at both ends. Erfurt is somewhat to the north of the midpoint, but could still keep a timed transfer between trains to Munich, Frankfurt, and Berlin if everything were sped up.

Elsewhere, DB is currently investing in improving the line between Stuttgart and Munich. Trains today run on curvy track, taking about 2:13 to do 250 km. There are plans to build 250 km/h high-speed rail for part of the way, targeting a trip time of 1:30; the Deutschlandtakt map is somewhat less ambitious, calling for 1:36, with much of the speedup coming from Stuttgart21 making the intercity approach to Stuttgart much easier. But with a straight line distance of 200 km, even passing via Ulm and Augsburg, trains could do this trip in less than an hour at TGV speeds, which would fit well into a national takt as well. No timed transfers are planned at Augsburg or Ulm. The Baden-Württemberg map even shows regional trains (in blue) at Ulm timed to just miss the intercity trains to Munich. Likewise, the Bavaria map shows regional trains at Augsburg timed to just miss the intercity trains to Stuttgart.

The same principle applies elsewhere in Germany. The Deutschlandtakt tightly fits trains between Munich and Frankfurt, doing the trip in 2:43 via Stuttgart or 2:46 via Nuremberg. But getting Munich-Stuttgart to just under an hour, together with Stuttgart21 and a planned bypass of the congested Frankfurt-Mannheim mainline, would get Munich-Frankfurt to around two hours flat. Via Nuremberg, a new line to Frankfurt could connect Munich and Frankfurt in about an hour and a half at TGV speed; even allowing for some loose scheduling and extra stops like Würzburg, it can be done in 1:46 instead of 2:46, which fits into the same integrated plan at the two ends.

The value of a tightly integrated schedule is at its highest on regional rail networks, on which trains run hourly or half-hourly and have one-way trip times of half an hour to two hours. On metro networks the value is much lower, partly because passengers can make untimed transfers if trains come every five minutes, and partly because when the trains come every five minutes and a one-way trip takes 40 minutes, there are so many trains circulating at once that the run-as-fast-as-necessary principle makes the difference between 17 and 18 trainsets rather than that between two and three. In a large country in which trains run hourly or half-hourly and take several hours to connect major cities, timed transfers remain valuable, but running as fast as necessary is less useful than in Switzerland.

The way forward for Germany

Germany needs to synthesize the two different rail paradigms of its neighbors – the integrated timetables of Switzerland and the Netherlands, and the high-speed rail network of France.

High investment levels in rail transport are of particular importance in Germany. For too long, planning in Germany has assumed the country would be demographically stagnant, even declining. There is less justification for investment in infrastructure in a country with the population growth rate of Italy or of last decade’s Germany than in one with the population growth rate of France, let alone one with that of Australia or Canada. However, the combination of refugee resettlement and a very strong economy attracting European and non-European work migration is changing this calculation. Even as the Ruhr and the former East Germany depopulate, we see strong population growth in the rich cities of the south and southwest as well as in Berlin.

The increased concentration of German population in the big cities also tilts the best planning in favor of the metropolitan-centric paradigm of France. Fast trains between Berlin, Frankfurt, and Munich gain value if these three cities grow in population whereas the smaller towns between them that the trains would bypass do not.

The Deutschlandtakt’s fundamental idea of a national integrated timed transfer schedule is good. However, a country the size and complexity of Germany needs to go beyond imitating what works in Switzerland and the Netherlands, and innovate in adapting best practices for its particular situation. People keep flying domestically since the trains take too long, or they take buses if the trains are too expensive and not much faster. Domestic flights are not a real factor in the Netherlands, and barely at all in Switzerland; in Germany they are, so trains must compete with them as well as with flexible but slow cars.

The fact that Germany already has a functional passenger rail network argues in favor of more aggressive investment in high-speed rail. The United States should probably do more than just copy Switzerland, but with nonexistent intercity rail outside the Northeast Corridor and planners who barely know that Switzerland has trains, it should imitate rather than innovating. Germany has professional planners who know exactly how Germany falls short of its neighbors, and will be leaving too many benefits on the table if it decides that an average speed of about 150 km/h is good enough.

Germany can and should demand more: BMVI should enact a program with a budget in the tens of billions of euros to develop high-speed rail averaging 200-250 km/h connecting all of its major cities, and redo the Deutschlandtakt plans in support of such a network. Wedding French success in high-speed rail and Swiss and Dutch success in systemwide rail integration requires some innovative planning, but Germany is capable of it and should lead in infrastructure construction.

# Positive and Negative Interactions

This is a theoretical post about a practical matter that arises whenever multiple variables interact. Two variables x and y, both correlated positively a dependent variable z, are said to positively interact if when x is larger, the effect of y on z gets larger and vice versa, and to negatively interact if when x is larger, the effect of y on z gets smaller. If z is transit ridership, let alone any of the direct benefits of good transit (good job access, environmental protection, public health, etc.), then it is affected by a slew of variables concerning service provision, infrastructure, and urban design, and they interact in complex ways.

I have not found literature on this interaction, which does not mean that this literature does not exist. The papers I’ve seen about correlates of bus ridership look at it one variable at a time, and yet they are suggestive of positive as well as negative interactions. More broadly, there are interactions between different types of service.

Positive interactions tend to involve network effects. These include the interaction between transit and transit-oriented development, as well as that between different aspects of rail modernization. Whenever there is positive interaction between variables, half-measures tend to flop; some are a reverse 80/20 situation, i.e. 80% of the cost yields 20% of the benefits. In some cases, compromises are impossible without making service useless. In others, some starter service is still viable, but in its presence, the case for expansion becomes especially strong, which can lead to a natural virtuous cycle.

Negative interactions occur when different improvements substitute for one another. One straightforward example is bus stops and frequency: frequency and the quality of bus shelter both impact bus ridership, but have a negative interaction, in that at higher frequency, the inconvenience coming from not having bus shelter is less important. In some cases, negative interactions can even lead to either/or logic, in which, in the presence of one improvement, another may no longer be worth the economic or political cost. In others it’s still useful to pursue multiple improvements, but the negative interaction implies the benefits are not as great as one might assume in isolation, and transit planners and advocates must keep this in mind and not overpromise.

Door-to-door trip times

The door-to-door trip time includes walking distance to and from the station, waiting time, transferring time, and in-vehicle time. Each of these components affects ridership in that longer trips reduce people’s propensity to choose public transport.

There is strong positive interaction between variables affecting the trip time. This is not directly attested in the literature that I know of, but it is a consequence of any ridership model that lumps the different components of trip time into one. If public transportation runs faster, that is if the in-vehicle time is reduced, then the share of the other components of the trip time rises, which means that the importance of frequency for reducing wait time is increased. Thus, speed and frequency have a positive interaction.

However, at the same time, there is a subtle negative interaction between speed and service provision on buses. The reason is that bus operating expenses are largely a linear function of overall service-hours, since costs are dominated by driver wages, and even maintenance is in practice a function of service-hours and not just service-km, since low speeds come from engine-stressing stop-and-go traffic conditions. In this case, increasing the speed of buses automatically means increasing their frequency, as the same resources are plugged into more service-km. In that case, the impact of a further increase in service is actually decreased: by speeding up the buses, the transit agency has reduced the share of the door-to-door trip time that is either in-vehicle or waiting at a stop, and thus further reductions in wait time are less valuable.

In the literature, the fact that investing in one portion of the trip makes its share of the overall trip length smaller and thus reduces the impact of further investments is seen in research into ridership-frequency elasticity. My standard references on this – Lago-Mayworm-McEnroe and Totten-Levinson – cite lit reviews in which the elasticity is far higher when frequency is low than when it is high, about 1 in the lowest-frequency cases and 0.3 in the highest-frequency ones. When frequency is very low, for example hourly, the elasticity is so high that adding service increases ridership proportionally; when frequency is a bus every few minutes, the impact of service increase on ridership is much smaller.

I’ve focused on in-vehicle time and waiting time, but the other two components are sometimes within the control of the transit agency as well, especially on rapid transit. Station design can reduce transfer time by providing clear, short passageways between platforms; it can also reduce access time by including more exits, for example at both ends of the platform rather than just at one end or in the middle. As such design positively interacts with other improvements to speed, it makes sense to bundle investments into more exits and better transfers with programs that add train service and speed up the trains.

Network effects

There is positive interaction between different transit services that work together in a network. In the presence of a north-south line through a city, the case for east-west transportation strengthens, and vice versa. This is not a new insight – Metcalfe’s law predicts usage patterns of communications technologies and social networks. The same effect equally holds for fixed infrastructure such as rail, and explains historical growth patterns. The first intercity steam railway opened in 1830, but the fastest phase of growth of the British rail network, the Railway Mania, occurred in the late 1840s, after main lines such as the London and Birmingham had already been established. 150 years later, the first TGV would start running in 1981, but the network’s biggest spurt of growth in terms of both route-km and passenger numbers occurred in the 1990s.

Using a primitive model in which high-speed rail ridership is proportional to the product of city populations, and insensitive to trip length, the United States’ strongest potential line is naturally the Northeast Corridor, between Boston and Washington. However, direct extensions of the line toward Virginia and points south are extremely strong per the same model and, depending on construction costs, may have even higher return on investment than the initial line, as 180 km of Washington-Richmond construction produce 540 km of New York-Richmond passenger revenue. In some places, the extra link may make all the difference, such as extending New York-Buffalo high-speed rail to Toronto; what looks like a basic starter system may be cost-ineffective without the extra link.

Network effects produce positive interactions not just between different high-speed rail lines, but also between transit services at lower levels. Rail service to a particular suburb has positive interaction with connecting bus service, for which the train station acts as an anchor; in some cases, such as the Zurich model for suburban transit planning, these are so intertwined that they are planned together, with timed transfers.

Network effects do not go on forever. There are diminishing returns – in the case of rail, once the biggest cities have been connected, new lines duplicate service or connect to more marginal nodes. However, this effect points out to a growth curve in which the first application has a long lead time, but the next few additions are much easier to justify. This is frustrating since the initial service is hard to chop into small manageable low-risk pieces and may be canceled entirely, as has happened repeatedly to American high-speed rail lines. And yet, getting over the initial hurdle is necessary as well as worth it once subsequent investments pan out.

Either-or improvements

In the introduction, I gave the example of negative interaction between bus shelter amenities and frequency: it’s good to have shelter as well as shorter waits, but if waits are shorter, the impact of shelter is lessened. There are a number of other negative interactions in transit. While it is good to both increase bus frequency and install shelter at every stop, some negative interactions lead to either-or logic, in which once one improvement is made, others are no longer so useful.

Fare payment systems exhibit negative interactions between various positive features. The way fare payment works in Germany and Switzerland – paper tickets, incentives for monthly passes to reduce transaction costs, proof of payment – is efficient. But the same can be said about the smartcard system in Singapore, EZ-Link. EZ-Link works so rapidly that passengers can board buses fast, which reduces (but does not eliminate) the advantage of proof-of-payment on buses. It also drives transaction costs down to the point of not making a monthly pass imperative, so Singapore has no season passes, and it too works.

Interior circulation displays negative interactions as well. There are different aspects of rolling stock design that optimize for fast boarding and disembarking of passengers, which is of critical importance on the busiest rail lines, even more than interior capacity. Trains so designed have a single level, many doors (four pairs per 20-meter car in Tokyo), interiors designed for ample standing space, and level boarding. Each of these factors interacts negatively with the others, and in cities other than Tokyo, regional trains like this are overkill, so instead designers balance circulation with seated capacity. Berlin has three door pairs per car and seats facing front and back, Zurich has double-deckers with two pairs of triple-wide doors and has been quite tardy in adopting level boarding, Paris has single-level cars with four door pairs and crammed seats obstructing passageways (on the RER B) and bespoke double-deckers with three pairs of triple-wide doors (on the RER A).

Finally, speed treatments on scheduled regional and intercity trains may have negative interactions. The Swiss principle of running trains as fast as necessary implies that once various upgrades have cut a route’s trip time to that required for vigorous network connections – for example, one hour or just a few minutes less between two nodes with timed transfers – further improvements in speed are less valuable. Turning a 1:02 connection into a 56-minute one is far more useful than further turning a 56-minute service into a 50-minute trip. This means that the various programs required to boost speed have negative interactions when straddling the boundary of an even clockface interval, such as just less than an hour, and therefore only the cheapest ones required to make the connections should receive investment.

Conclusion

Good transit advocates should always keep the complexities that affect transportation in mind. Negative interactions between different investments have important implications for activism as well as management, and the same is true for positive interactions.

When variables interact negatively, it is often useful to put a service in the good enough basket and move on. In some cases, further improvements are even cost-ineffective, or require unduly compromising other priorities. Even when such improvements remain useful, the fact that they hit diminishing returns means advocates and planners should be careful not to overpromise. Cutting a two-hour intercity rail trip to an hour is great; cutting a 40-minute trip to a 20-minute one may seem like a game changer, but really isn’t given the importance of access and egress times, so it’s usually better to redeploy resources elsewhere.

Conversely, when variables interact positively, transit service finds itself in an 80% of the cost for 20% of the benefits situation. In such case, compromises are almost always bad, and advocates have to be insistent on getting everything exactly right, or else the system will fail. Sometimes a phased approach can still work, but then subsequent phases become extremely valuable, and it is useful to plan for them in advance; other times, no reasonable intermediate phase exists, and it is on activists to convince governments to spend large quantities of upfront money.

Transportation is a world of tradeoffs, in which benefits are balanced against not just financial costs but also costs in political capital, inconvenience during construction, and even activist energy. Positive and negative interactions have different implications to how people who want to see better public transport should allocate resources; one case encourages insisting on grand plans, another encourages compromise.

# The California HSR Bombshell, Redux

California Governor Gavin Newsom spoke his piece, and California HSR is most likely dead. His state of the state speech tried to have it both ways, and his chief of staff insisted that no, he had not just canceled the HSR project, but his language suggests he’s not going to invest any more money or political capital in going beyond the Central Valley. Lisa Schweitzer put it best when she talked about his sense of priorities.

I actually don’t want to talk about the costs of the project; an article about this topic will appear in the Bay City Beacon any day now, and I will update this post with a link when it does. Rather, I want to talk about alignments. For those of you who’ve been reading me since the start, this means reopening some topics that involved tens of thousands of comments’ worth of flamewars on California HSR Blog.

What they should be building

As before, red denotes HSR with top speed of 350 km/h outside the built-up areas of the largest cities, and blue denotes legacy lines with through-service. I ask that people not overinterpret pixel-level alignments. The blue alignment in Southern California is the legacy route taken by Amtrak, the one in the Bay Area is a legacy line from Fremont to San Jose that some area transit advocates want a Caltrain extension on (and if it’s unavailable then it can be deleted with a forced transfer to BART), the one in the far north of the state is the freight line up to Redding.

The mid-2000s environmental impact study claims that Los Angeles-San Francisco via Altamont Pass would take 2:36 nonstop. The Tejon route I’m drawing is 12 minutes faster, so in theory this is 2:24. But three express stops in the middle, even in lower-speed territory right near Los Angeles and San Francisco, lead to somewhat longer trip times, as do various design compromises already made to reduce costs. My expectation is that the alignment drawn is about 2:45 on LA-SF and somewhat less on LA-Sacramento, on the order of 2:15 nonstop.

Why Tejon and not the Tehachapis

There are two ways to get between Los Angeles and Bakersfield. The first is the alignment taken by the I-5, called the Grapevine or Tejon Pass. The second is to detour far to the east via Palmdale and Tehachapi Pass. The alignment I drew is Tejon, that chosen by the HSR Authority is the Tehachapis.

Clem Tillier made a presentation about why Tejon is far superior. It is shorter, reducing trip times by about 12 minutes. It is less expensive, since the shorter length of the route as well as the reduced tunneling requirement means fewer civil structures are required; Clem’s presentation cites a figure of $5 billion, but with recent overruns I’ve heard a figure closer to$7 billion.

The exact cost of either alignment depends on standards. Unlike Northeastern passenger rail efforts, which are based on bad American design standards that recommend very shallow grades, ideally no more than 1.5-2%, California HSR uses a generic European standard of up to 3.5%, the same as in France. However, 3.5% is a conservative value, designed around TGVs, which almost uniquely in the HSR world have separate power cars. Distributed traction, that is EMUs, has higher initial acceleration and can climb steeper grades. One German HSR line goes up to 4%, and only the EMU ICE 3 train is allowed to use it, not the ICE 1 and 2, which have power cars like the TGVs. Even 5% is achievable far from stations and slow zones, which would reduce tunneling requirements even further.

In the mid-2000s, it was thought that the Tehachapi alignment could be done with less tunneling than Tejon. Only one 3.5% alignment through Tejon was available without crossing a fault line underground, so Tehachapi seemed safer. But upon further engineering, it became clear more tunneling was needed through Soledad Canyon between Los Angeles and Palmdale, while the Tejon alignment remained solid. The HSR Authority resisted the calls to shift to Tejon, and even sandbagged Tejon in its study, for two reasons:

1. Los Angeles County officials favored the Tehachapi route in order to develop Palmdale around the HSR station.

2. A private real estate company called Tejon Ranch planned to build greenfield development near the Tejon HSR route called Tejon Mountain Village, and opposed HSR construction on its property.

As Clem notes, the market capitalization of Tejon Ranch is about an order of magnitude less than the Tehachapi-Tejon cost difference. As for the county’s plans for Palmdale, spending 5 billion on enabling more sprawl in Antelope Valley is probably not the state’s highest priority, even if an HSR station for (optimistically) a few thousand daily travelers in a region of 400,000 exists to greenwash it. Why follow the coast to San Diego Two years ago I wrote an article for the Voice of San Diego recommending electrifying the Los Angeles-San Diego Amtrak line and running trains there faster, doing the trip in about 2 hours, or aspirationally 1:45. Amtrak’s current trip time is 2:48-2:58 depending on time of day. The alignment proposed by the HSR Authority instead detours through the Inland Empire. The good thing about it is that as a greenfield full-speed route it can actually do the trip faster than the legacy coast line could – the plan in the 2000s was to do it in 1:18, an average speed of about 190 km/h, on account of frequent curves limiting trains to about 250 km/h. Unfortunately, greenfield construction would have to be postponed to phase 2 of HSR, after Los Angeles-San Francisco was complete, due to costs. Further design and engineering revealed that the route would have to be almost entirely on viaducts, raising costs. If I remember correctly, the estimated cost of the HSR Authority’s proposed alignment to San Diego was10 billion in the early 2010s, about $40 million per kilometer (and so far Central Valley costs have been higher). Even excluding the Los Angeles-Riverside segment, which is useful for HSR to Phoenix, this is around$7 billion for cutting half an hour out of trips from Los Angeles and points north to San Diego. Is it worth it? Probably not.

What is more interesting is the possibility of using the Inland Empire detour to give San Diego faster trips to Phoenix and Las Vegas. San Diego-Riverside directly would be around 45 minutes, whereas via Los Angeles it would be around 2:20.

However, the same question about the half hour’s worth of saving on the high-speed route can equally be asked about connecting San Diego to Las Vegas and Phoenix. These are three not especially large, not especially strong-centered cities. The only really strong center generating intercity travel there is the Las Vegas Strip, and there San Diego is decidedly a second-order origin compared with Los Angeles; the same is even true of San Francisco, which could save about 40 minutes to Las Vegas going via Palmdale and Victorville, or 55 minutes via Mojave and Barstow.

Ultimately, the non-arboreal origin of money means that the $7 billion extra cost of connecting Riverside to San Diego is just too high for the travel time benefits it could lead to. There are better uses of$7 billion for improving connectivity to San Diego, including local rail (such as a light rail tunnel between city center and Hillcrest, branching out to Mid-City and Kearny Mesa) and a small amount of extra money on incrementally upgrading the coast line.

Why Altamont is better than Pacheco

I’m leaving the most heated issue to last: the route between the Central Valley and the Bay Area. I am not exaggerating when I am saying tens of thousands of comments have been written in flamewars on California HSR Blog over its ten years of existence; my post about political vs. technical activists treated this flamewar as almost a proxy for which side one was on.

The route I drew is Altamont Pass. It carries I-580 from Tracy to Livermore, continuing onward to Pleasanton and Fremont. It’s a low pass and trains can go over the pass above-ground, and would only need to tunnel further west in order to reach Fremont and then cross the Bay to Redwood City. Many variations are possible, and the one studied in the mid-2000s was not the optimal one: the technical activist group TRANSDEF, which opposes Pacheco, hired French consultancy SETEC to look at it and found a somewhat cheaper and easier-to-construct Altamont alignment than the official plan. The biggest challenge, tunneling under the Bay between Fremont and Redwood City, is parallel to a recently-built water tunnel in which there were no geotechnical surprises. Second-hand sources told me at the beginning of this decade that such a rail tunnel could be built for \$1 billion.

Pacheco Pass is far to the south of Altamont. The route over that pass diverges from the Central Valley spine in Chowchilla, just south of Merced, and heads due west toward Gilroy, thence up an alignment parallel to the freight line or US 101 to San Jose. The complexity there is that the pass itself requires tunneling as the terrain there is somewhat more rugged than around Altamont.

As far as connecting Los Angeles and San Francisco goes, the two alignments are equivalent. The old environmental impact reports stated a nonstop trip time of 2:36 via Altamont and 2:38 via Pacheco; Pacheco is somewhat more direct but involves somewhat more medium-speed running in suburbia, so it cancels out. The early route compromises, namely the Central Valley route, affected Altamont more than Pacheco, but subsequent compromises in the Bay Area are the opposite; nonetheless, the difference remains small. However, Pacheco is superior for service between Los Angeles and San Jose, where it is about 10 minutes faster, while Altamont is superior for service between the Bay Area and Sacramento, where it is around an hour faster and requires less additional construction to reach Sacramento.

As with the Tehachapis, the Authority sandbagged the alignment it did not want. San Jose-based HSR Authority board member Rod Diridon wanted Pacheco for the more direct route to Los Angeles, perhaps realizing that if costs ran over or the promised federal and private funding did not materialize, all three of which would indeed happen, the spur to San Jose was the easiest thing to cut, leaving the city with a BART transfer to Fremont. Consequently, the Authority put its finger on the study’s scale: it multiplied the frequency effect on passenger demand by a factor of six, to be able to argue that splitting trains between two Bay Area destinations would reduce ridership; it conducted public hearings in NIMBY suburbs near Altamont but not in ones near Pacheco; and early on it even planned to build San Francisco-San Jose as its first segment, upgrading Caltrain in the meantime.

And as with the Tehachapis, the chosen route turned out to be worse than imagined. Subsequent business plans revealed more tunneling was needed. The route through San Jose itself was compromised with curvy viaducts, and the need to blend regional and intercity traffic on the Caltrain route forced further slowdowns in intercity train speed, from a promised 30 minutes between San Francisco and San Jose to about 45. The most recent business plan even gave up on high speed between Gilroy and San Jose and suggested running on the freight mainline in the initial operating stage, at additional cost and time given Union Pacific’s hostility to passenger rail.

What is salvageable?

The HSR Authority has made blunders, perhaps intentionally and perhaps not, that complicate any future project attempting to rescue the idea of HSR. In both Los Angeles and the Bay Area, delicate timetabling is needed to blend regional and intercity rail. Heavy freight traffic interferes with this scheduling, especially as Union Pacific demands unelectrified track, generous freight slots, and gentle grades for its weak diesel locomotives, frustrating any attempt to build grade-separations cheaply by using 3-4% grades. Caltrain’s trackage rights agreement with UP contained a guillotine clause permitting it to kick freight off the line if it changed in favor of an incompatible use, originally intended to permit BART to take over the tracks; Caltrain gave up this right. UP is not making a profit on the line, where it runs a handful of freight trains per day, but the industrial users insisted on freight rail service.

Likewise, the Central Valley segment has some route compromises baked in, although these merely raise costs rather than introducing forced slowdowns or scheduling complications. A future project between Merced, the northern limit of current construction, and Sacramento, could just spend more time early on negotiating land acquisitions with the farmers.

It is in a way fortunate that in its incompetence, the HSR Authority left the most important rail link in the state – Los Angeles-Bakersfield – for last. With no construction on the Tehachapi route, the state will be free to build Tejon in the future. It will probably need to buy out Tejon Mountain Village or add some more tunneling, but the cost will still be low compared with that of the Palmdale detour.

Ultimately, the benefits of HSR increase over time as cities increase in size, economic activity, and economic connectivity. The Shinkansen express trains ran hourly in 1965; today, they run six times per hour off-peak and ten at the peak. Going back even earlier, passenger traffic on the London Underground at the beginning of the 20th century was not impressive by today’s standards. The fact that national rail traffic plummeted in most developed countries due to the arrival of mass motorization should not distract from the fact that overall travel volumes are up with economic growth, and thus, in a growing area, the case for intercity rail investment steadily strengthens over time.

Chickenshit governors like Newsom, Andrew Cuomo, and Charlie Baker are not an immutable fact of life. They are replaced after a few terms, and from time to time they are replaced by more proactive leaders, ones who prefer managing big-ticket public projects successfully to canceling them or scaling them back on the grounds that they are not competent enough to see them through.