The utilization of leftover spaces of Sri Lankan expressways: insights from the Kadawatha interchange

Abstract

Expressways are a relative novelty to the transportation infrastructure and landscape development of Sri Lanka. The same is true of the leftover spaces created alongside said infrastructure. Leftover spaces are places that have been severely neglected in terms of landscape design over the years. Due to the development of transportation, the number of unutilized leftover spaces has increased and led to various misuses. This investigation focuses on how these leftover spaces can be utilized appropriately by analyzing the global perspective on such spaces. Meta-analysis and summarization of outcomes based on previous research are used to formulate a theoretical framework for the aspect of human perception and user preferences. A sequential mixed-method approach incorporating both qualitative and quantitative methods was used to evaluate physical, social, environmental, and economic aspects of expressway leftover spaces. The questionnaire (n=22) focused on the above selected aspects was given to two groups (users and experts in the field). Snowball techniques were used for data collection and statistical methods were used to gauge the importance of each factor. Locally, a series of interchanges have been studied for their locations and distribution in a pilot study and one case study was isolated for the main study. Both the users of these areas and experts on the subject have been surveyed for insights. The research provides 19 recommendations with high preferences for creating green spaces and public artworks in these spaces. They are meant to be scalable and easy to implement across a wide variety of conditions that are likely to arise in the expressway development. According to the survey, it is possible to create standards and guidelines that apply to most leftover highway space scenarios in Sri Lanka. Immediate utility and convenience to the user are given high importance with security being the most important aspect that should not be compromised. The survey can be used as insights for future developments.