Premetro

Not to be confused with Light metro or Tram-train.
Trams at Saint-Gilles/Sint-Gillis station with partially low platforms in Brussels.
Low platform section for trams at Duisburg Hauptbahnhof Stadtbahn station.
Low platform station for trams in Vienna during transformation. A third rail and emergency stairs from the future high platform have already been installed.

Premetro (sometimes pre-metro) is a type of light rail transit. Here infrastructure is gradually built with the goal to use rapid transit trains in the distant future, but using trams or light rail vehicles preliminary in the meantime. This infrastructure consists of tunnels and/or viaducts, so vehicles have no conflicts with other traffic. To achieve that these rapid trains will be able to use the infrastructure, wider curves and lesser grades need to be designed and built.[1][2][3][4][5]

The use of tram vehicles in tunnels originated in the United States in the nineteenth century and was often called "subway surface line" while in the second half of the twentieth century the term "semi-metro" was coined. Only when a semi-metro section is designed for later use of heavy rapid transit, it also falls in the premetro category.[6] During the time when tram vehicles are used, the specific line falls into the light rail category.[7][8]

  1. ^ Transit Capacity and Quality of Service Manual. Transportation Research Board. 2013. ISBN 978-0-309-28344-1. pre-metro — a light rail transit system designed with provisions for easy conversion to heavy rail (rail rapid transit).
  2. ^ De Leuw, Cather & Company (1976). Light Rail Transit: A State of the Art Review, Executive Summary. p. 47. Retrieved 30 August 2023. This step-by-step planning approach to building rail rapid transit is known as pre-metro, implying the intention to ultimately construct a fully grade separated route to be used by rail rapid transit or metro trains.
  3. ^ Jenkin, P. (1988). Urban Railways and the Civil Engineer. Thomas Telford. ISBN 978-0-7277-1337-7. Retrieved 9 August 2024. Pre-Metro is an extreme case of light rail, on segregated right of way, and designed to upgrading to metro when passenger demand increases sufficiently.
  4. ^ Mattila, Matti (5 August 2012). Wizzit Magazine 3/2011. Annorlunda Mediatuotanto Oy. p. 19. ISBN 978-1-4478-2842-6. Retrieved 9 August 2024. Premetros also allow a gradual upgrade of existing tramways to rapid transit, thus spreading the investments costs over time.
  5. ^ John Hoyle (16 May 1975). "Letters to the editor -- The tram is the answer". Sydney Morning Herald. Retrieved 13 January 2014. Cities such as Frankfurt and Cologne in West Germany have further developed their tramway system by introducing a concept known as "premetro." In this system trams or light rail vehicles make extensive use of tunnels, reserve track and by utilizing folding steps these vehicles can operate through high or low stopping places.
  6. ^ "PREMETRO [1 record]". TERMIUM Plus®. 8 October 2009. Retrieved 23 July 2024.
  7. ^ Transportation Research Board National Research Council (1989). Urban Public Transportation Glossary. Retrieved 16 February 2023. pre-metro: a light rail transit system designed with provisions for easy conversion to rail rapid transit
  8. ^ Vuchic, Vukan R. (2007). Urban transit systems and technology. Hoboken, N.J: J. Wiley & Sons. p. 580. doi:10.1002/9780470168066.fmatter. ISBN 9780471758235. Retrieved 7 October 2023. PREMETRO—An LRT system designed with provisions for easy conversion into RRT (metro).