The role of city geometry in determining the utility of a small urban light rail/tram system

TL;DR

This paper emphasizes the significance of city geometry in urban transport planning, demonstrating how city shape influences the utility of light rail systems through new concepts and a case study of Galway City.

Contribution

It introduces the concepts of Infeasible Regions and Infeasibility Factors, providing methods to calculate them and analyzing their impact on light rail utility based on city shape.

Findings

Circular cities have different light rail utility profiles compared to rectangular cities.

Rectangular cities show greater utility for single-line light rail systems.

Methods for calculating Infeasible Regions are presented and applied.

Abstract

In this work, we show the importance of considering a city's shape, as much as its population density figures, in urban transport planning. We consider in particular cities that are circular (the most common shape) compared to those that are rectangular: For the latter case we show greater utility for a single line light rail/tram system. We introduce the new concepts of Infeasible Regions and Infeasibility Factors, and show how to calculate them numerically and (in some cases) analytically. A particular case study is presented for Galway City.