Costs and Benefits of Underground Railway Constructiont by Gunter Girnau*
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UNDERGROUND SPACE Marienplatz Station in Munich. The city of Munich opened its first subway (U-Bahn) line in 1977 and since that time has expanded the underground - system, investing an average annual rate of DM200 million. Costs and Benefits of Underground Railway Constructiont by Gunter Girnau* ccording_to the results of a rep• massive financial support that has been The immediate benefits of this huge resentative survey, m recent given to promote local public transport investment program in terms of in• A years the image of local public in the past 15 years. Since 1967, when creased ridership and convenience to passenger transport in the Federal Re• federal funds first became available, a the individual passenger can easily be public of Germany has improved con• 30-year program of planning and in• seen. What is not so obvious is that the siderably. This is largely a result of the vestment in public transport has been public interest has been served in a under way nationwide. It is now "half• number of other ways. Reduced noise, tRevised and reprinted with permission from time" in the 30-year program. A de• improved air quality, fewer traffic ac• Advances in Tunnelling Technology and Sub• cidents, and a positive economic effect surface Use (Developpement des Travaux en tailed breakdown of the funds as ac• Souterrain), Volume 2, No.2, 1982. Oxford: tually invested and of the construction on the community can also be counted Pergamon Press. work already done is now available, and among the benefits of this program. "'Professor Dr.-Ing. Gunter Girnau is pres• equally important, the program has Indeed, a cost-benefit analysis of public ident of the International Tunnelling As• advanced to the stage where prelimi• transport that did not include these sociation (ITNAITES) and president of STUVA, nary conclusions can be drawn from benefits would be remiss. This brief Cologne, Federal Republic of Germany. what has been achieved. survey of Germany's revitalized public Underground Space, Vol. 6, pp. 323-330, 1982 0362-0565/82/060323-08$03.00/0 Printed in the U.S.A. All rights reserved. Copyright © 1982 Pergamon Press Ltd. 323 transport system will consider both the DM13.4 billion (61%) went toward un• costs and the various benefits of this derground (U - Bahn), metropolitan AVERAGE CONSTRUCTION COST PE R KM huge undertaking. (light rail, or Stadtbahn) and tramway systems. This was followed by the DM7.3 DM in mil l West Germany's Investment billion (33%) spent selectively on the per km in Public Transport German Railways' rapid transit systems 50 (commuter railways, or S-Bahn). Most Between 1967 and 1980, federal, of the remaining DM1.3 billion was used 45 state, and local governments, German to extend or construct service stations Railways, and individual transport 40 and workshops, central bus stations, in• companies spent a total of DM22 bil• terchange stations, park-and- ride fa• 25 lion on extending the facilities of pub• cilities, or grade separating structures. lic passenger transport systems. Be• The funds invested during the first tween 1967 and 1975, in particular, there was a marked upturn in the level 14 years of the development program have genera ted a huge volume of con• of annual investment (Fig. 1). Since 1977, the annual yearly expenditure ' struction work. has been in the range of DM2 billion to DM2.3 billion. Facilities for The major sources of funds over the municipal railway systems years were the federal and state gov• The development program covers the ernments, which provided 52% and following projects: 20% respectively. (The chief basis for • All-out underground systems (U• financing today is the Municipal Fi• Bahn) are now in operation or are (23% in tunnel) (78% in tunnel) nance Transport Act- being extended in Berlin, Ham• Gemeinver• kehrsfinanzierungsgesetz. burg, Munich, and Nuremberg• Figure 2. Cost comparison between sub• The federal share is currently some cities, with the exception of Nur• way (U -Bahn) and light rail (Stadt• 60%.) The amount provided by emberg, having populations ex• local govern• ment- 24%- is bahn) systems. ceeding one million. much higher than is generally assumed. However, as own• ers of • Metropolitan systems (light rail , or Mulheim/Ruhr, and Stuttgart• local transport systems, local Stadtbahn) are being built in 17 cities whose populations vary widely governments bear the cost of the roll• cities: Bielefeld, Bochum, Bonn, between 200,000 and 900,000. ing stock, which amounts to DM600 Bremen, Cologne, Dortmund, million annually. Dusseldorf, Duisberg, Essen, • To finance extensions to their tram networks, 11 cities have received in• The major portion of funds was in• Frankfurt/Main , Gelsenkirchen, vestment assistance: Augsburg, vested in improving and extending Hanover, Herne, Ludwigshafen, Brunswick, Darmstadt, Freiburg, railway traffic; by far the largest amount, Karlsruhe, Kassel, Nuremberg, and Wurzberg- cities having 1 ,000 mill . DM popula• tions ranging between 100,000 and 2.4 200,000. D PRIVATE PROJECTS 2.2 By the end of the construction period (:::::::::::::1 FEDERA L RAILWAY PROJECTS (1967-1980), some 180 km of new non• intersecting routes (tunnel, cutting, el• 2.0 MUNI CIPA L PROJEC TS evated) as well as 250 km of on-grade 1 .8 routes (special right-of-way) with a to• tal of 720 stops were put into operation 1 .6 in the municipal railway sector. 1.4 German Railways' rapid transit system (S -Bahn) 1.2 To open up the region by rapid transit (S-Bahn), 100 km of new track with 1.0 145 stops were laid and 490 km of ex• isting track with 164 stations were con• 0.8 verted to commuter railways and opened to traffic. Again as much con• 0.6 struction work is planned for the near future- an additional 125 km of 0.4 new track will be laid and 405 km of existing track is to be converted. 0.2 The Costs o U- UL _L a_ 1967 1 970 1971 The question of costs- and • Munic ipal and pr ivate projects not sep ar a ted. espe• cially of costs for subsurface construc• tion- is always difficult to Figure 1. Investment in local public passenger transport during the first 12 years answer. There are so many factors of the Federal Republic's 30-year planning and investment program. influencing costs that they may vary between 30 million 324 UNDERG ROU N D SPACE to 80 million DM per kilometer of un• derground railway tunnel (with all in• How the funds were invested stallations including stations). In the DM13.4 billion = 61% --? Underground 180 km non-intersect- same city, costs vary considerably from (U-Bahn) ing routes line to line and even from contract to contract. It is virtually meaningless, --? Metropolitan 250 km on-grade therefore, to talk about cost per kilo• (Light rail, or routes meter in a general sense, for the cost Stadtbahn) 720 stations and is never general. Having said that, however, some figures indicative of costs --? Tramway stops can be given. (Strassenbahn) The main factor influencing the cost DM7.3 billion 33% --? Commuter railways 100 km new track of railway construction is the relation between the length of a line in tunnel (S-Bahn) 145 new stations and and at grade. This relation is markedly stops different between the U-Bahn and the 490 km existing track S-Bahn. The results of the first eleven years of construction are: converted 164 existing stations U-Bahn: 78% of track length in tun• converted nel; overall costs 35 million to 40 DM1.3 billion 6% --? Workshops million DM/km --? Central bus stations (tunnel and at grade) S-Bahn: 23% of track length in tun• --? Interchange stations nel; --? Park-and-ride overall costs 20 million to 25 --? Grade separation million DM/km (tunnel and at grade) DM22 billion 100% The figures show that the U-Bahn is nearly twice as expensive as a light rail system on separated track (Stadtbahn). cost (See Fig. 2.) (OM per m track) Another important factor influenc• 60,000 ing the cost of underground construc• tion is the tunneling method (which depends on the ground conditions). For 50,000 example, a tunnel in water-bearing soft NATM ground may cost two to three times 40,000 +---+----+--+----+=....-=+1-o---""""....._c----+'o"---_-+----fo'i---+---+---l I . more using the compressed-air shield shield dr --'""-<:L---- ', driven method than if the tunnel had been excavated using the cut-and-cover 30,000 -t-----,.!-+ --+---+----+---+---t---+---ll------t....o_-=\"""""";:l--+- ;if' .......... o..... approach. However, the experience in Germany has been that the technolog• 20,000t---r- ··-··_··- op e_n cu t--t--r-. o7.-··4PO ·- ··· -- -· · ---- --- ical developments between 1966 and ..-o···· 1979, as well as the very strong com• 10,000 t---+---l--+---+---l--+---+---11--+---+--1---1 petition among contractors has mark• edly reduced the cost differential be• tween the cut-and -cover approach and 1966 67 68 69 70 71 72 73 74 75 76 77 the "underground" tunneling meth• ods. In Munich today, the costs for the Figure 3. The cost differential between the New Austrian Tunnelling Method, the New Austrian Tunnelling Method shield method, and the open cut has been markedly reduced. (NATM), the shield method, and the open cut are very close together (Fig. 3). There are instances in Munich and Federal Republic's entire transporta• period of approximately 30 years was other German cities where the NATM tion development program . While con• assumed for the implementation of the is already cheaper- especially when struction prices could be kept on the total development plan, an interim sur• the costs for environmental protection same level during the 1970's due to vey cannot have complete data: con• are taken into consideration.