Durban is famous for its iconic beachfront and for being the largest container port in the Southern Hemisphere. However, tucked in a complex river delta with 17 estuaries and exposed to tropical cyclones and heavy rainfall, the eThekwini Municipality constantly battles floods. The problem is exacerbated by climate change, accelerated sea level rise, and human-induced land subsidence.

After devastating floods in 2017 and 2019 resulted in massive economic damage, human displacement, and loss of life, the eThekwini initiated a new disaster management strategy to better prepare for future crises. The local government identified the need for real-time environmental observations and forecasts for flood prediction and preparation. They researched the installation and maintenance of a network of weather monitoring stations but faced a few obstacles. First, the existing solutions were too expensive. Second, the available instrumentation was cumbersome and easy to spot—making it vulnerable to theft. Third, available multichannel dataloggers with several wired external sensors weren’t robust enough for a massive disaster management program. Lastly, data were hard to gather and analyze without a centralized portal.

The government considered using point-to-point radio and LORA communication, but both were cost prohibitive and logistically complicated. Also, some flood-prone areas were outside the city or further offshore--making satellite communications imperative.

The municipality partnered with Obscape, a Netherlands-based environmental monitoring equipment manufacturer, to deploy Flood Early Warning Systems (FEWS) along the coastline to monitor storms and rising sea levels.

Obscape worked with Iridium partner Ground Control to create affordable yet robust solar-powered, wireless turnkey equipment to collect long-term, actionable environmental data.

Obscape integrated Ground Control’s RockBLOCK modem, enabled by the built-in Iridium^® 9603 module. The modem is at the heart of the Power Telemetry Module (PTM), an all-in-one datalogger and key component of the FEWS. The engineers mounted the systems above water on bridge decks, walls, trees, and poles near rivers in the flood hazard zones.

The Iridium 9603 module allows for a small enclosure and discreet appearance. Shaped like a 1-liter milk carton, the FEWS device can serve as a time-lapse camera, rain-level gauge, and weather station, forming one monolithic piece without external cables, which makes it inconspicuous, but also robust.

Another core monitoring system is the Iridium Connected wave buoy, which is equipped with sensors that detect wave height and direction – both important environmental data components. Thanks to the Iridium Short Burst Data^® (SBD^®) service, the FEWS provides critical, precise data to help water managers monitor flood-prone coastal areas, urban river corridors, and wetlands almost in real time. All data from the various measuring devices flow into a centralized portal, allowing seamless gathering and analysis.

The solution reduced municipality costs of sending field engineers to the monitoring sites, thus improving data-gathering efficiency.

Today, the eThekwini Municipality environmental monitoring network consists of 150 stations, which will expand to 200 sites over time. The network contains four wave buoys, 25 water level gauges, 55 rain gauges, 28 time-lapse cameras,seven weather stations, and more--covering 2,297 km2 (approximately 887 square miles).

Thanks to the Iridium Connected solution, eThekwini can receive threshold alerts and predictive environmental markers visualized in downloadable reports. The data allow the municipality to identify potential forecast patterns, which enable targeted responses to protect residents and safely manage port operations.