Assessment of Urban Traffic Characteristics, Vehicular Composition, and Stakeholder Perspectives on Emission Control in Major Cities of Nigeria

Abstract

Rapid urbanisation and motorisation in Nigeria have intensified vehicular emissions, contributing to air pollution and associated health risks. This study examined traffic characteristics, vehicular composition, and stakeholder perspectives on emission control in three major cities: Abuja, Kano, and Lagos. It combines quantitative traffic counts conducted from 6:00 a.m. to 6:00 p.m. along key urban corridors with surveys of 384 stakeholders, including government officials, commercial vehicle operators, transport union members, auto technicians, environmental advocates, and urban residents. Traffic data were analyzed for daily, hourly, and directional patterns, while vehicular composition and Passenger Car Unit calculations were used to assess road capacity impact. Survey responses were analyzed using descriptive statistics to summarize awareness, perceptions of emission sources, policy adequacy, and preferred mitigation strategies. Results revealed peak traffic periods in the morning and evening, with Lagos–Ibadan Expressway recording the highest volumes. Cars, mini buses, and heavy-duty vehicles were the most prevalent, while heavy vehicles exerted disproportionate influence on congestion and emissions. Stakeholders identified old vehicles, poor fuel quality, and weak regulation as major emission contributors, with 70% supporting stricter emission control measures. Suggested interventions included vehicle emission testing, phasing out high-emission vehicles, promoting public transport, strengthening enforcement, and raising public awareness. The findings underscore the critical link between traffic dynamics, vehicle types, and urban air pollution, highlighting areas for targeted policy and operational interventions. Implementing recommended strategies can reduce emissions, improve air quality, and guide sustainable transport planning in Nigerian cities, contributing to environmental protection, public health, and urban mobility efficiency.