In this paper, we present a sustainable Smart City Solid Waste Management System (SCSWMS) that integrates trending technologies such as Internet of Things (IoT), Low Power Wide Area Networks (LPWANs), and Intelligent Traffic Systems (ITS) to improve solid garbage management from its inception through disposal. The Proposed SCSWMS involves three main subsystems: Smart Garbage Bins (SGBs), Smart Garbage dump Trucks and urban Routes Selection (SGTRS), and Real-Time Users (drivers, dispatchers, citizens) Information and Decision Support (RTUIDS). The SGBs use IoT devices to monitor and collect the status of solid garbage bins and disseminate accurate information to SGTRS and RTUIDS subsystems using LoRaWAN technology. The SGTRS integrates a Geographic Position System (GPS) to optimize route selection, fuel and time consumption, and waste disposal. The RTUIDS informs users about the SGBs levels and estimated waste removal schedule and helps drivers and dispatchers to make more informed decisions. A proof of concept prototype implementation of the proposed SCSWMS was created and validated with both real and formal usability tests. Obtained results show improved bins monitoring accuracy, waste collection efficiency, and cost reduction, mainly than existing curbside collection methods.