The Evolving Urban Drainage Challenge

Something urgent is happening in our cities. Every heavy downpour disrupts transport, damages homes, and overwhelms basic services.

In rapidly growing urban areas across Africa, drainage and sanitation systems are under immense pressure due to increased rainfall variability, urban sprawl, and under-capacity infrastructure. According to the World Bank, Africa’s urban population is expected to double by 2050, intensifying the need for smart, scalable water infrastructure solutions.

Urban flooding is now a recurring challenge that demands forward-thinking design. Cities across the continent are actively seeking planning tools that not only respond to current needs but also anticipate future stressors. Among these tools, SewerGEMS stands out as a powerful hydraulic modelling software that enables engineers and urban planners to simulate, optimise, and enhance drainage networks with precision.

Designing Resilient Urban Systems

Drainage systems built decades ago were never designed for today’s storm intensity, population density, or impervious land cover. Informal settlements, poor drainage maintenance, and limited spatial planning often compound the issue.

This evolving complexity requires data-driven solutions that bring clarity to how water moves through space and infrastructure.

Read: Upskilling in Watergems is Key to Water Conservation

SewerGEMS: A Smarter Way to Plan Drainage Systems

SewerGEMS, developed by Bentley Systems, offers hydraulic and hydrologic modelling tools for sanitary and storm sewer systems. It empowers professionals to:

• Simulate drainage performance under various rainfall events.

• Visualise flow, volume, and surcharge scenarios across urban networks.

• Identify high-risk areas before infrastructure is built or upgraded.

• Optimise designs to improve capacity, cost-efficiency, and reliability

The platform integrates with ArcGIS, Civil 3D, and SCADA, allowing seamless collaboration across disciplines.

Why SewerGEMS Is Transforming Urban Infrastructure

SewerGEMS is increasingly being adopted in urban infrastructure planning across Africa. Here’s why it’s making an impact:

1. Stronger Flood Preparedness

By modelling rainfall-runoff scenarios, engineers can design systems that align with future weather extremes and urban growth projections. According to UN-Habitat, cities that implement predictive stormwater modelling see a 30–45% reduction in post-construction flooding events.

2. Cost-Effective Design Planning

SewerGEMS enables smarter decision-making by simulating the performance of various designs before construction begins. This reduces overdesign and costly post-construction adjustments.

3. Healthier, More Resilient Cities

Accurate sewer and stormwater modelling supports cleaner, safer cities by reducing overflow incidents that compromise sanitation and increase public health risks, particularly in informal settlements (WHO/UNICEF JMP, 2023).

Field Application: Drainage Upgrade in Dar es Salaam

In Dar es Salaam, the local infrastructure planning team used SewerGEMS to assess stormwater flow in low-lying neighborhoods. Through simulation and optimisation, they redesigned culverts and channel routes for a community of over 150,000 residents.

The project reported:

• 35% reduction in design time

• Streamlined permitting due to model-backed risk scenarios

• Improved system resilience during peak rainfall months

Looking Ahead: Building Cities That Withstand the Storm

Resilient cities begin with smart planning. SewerGEMS provides professionals with the tools to model urban water systems with accuracy, build more responsive drainage networks, and enhance public health outcomes.

Planners can now design with foresight using data, simulation, and strategy to protect their communities before the next flood exposes system gaps.

Build Your SewerGEMS Skills with IRES

IRES offers hands-on, simulation-based training to help engineers, urban planners, and water utility professionals effectively apply SewerGEMS in real-world African contexts. Participants gain practical experience in:

• Network layout and model setup

• Integrating rainfall and topographic data

• Scenario testing and performance reporting

• Planning drainage interventions suited to local needs

Whether you’re upgrading infrastructure or designing for resilience, our training equips you to model, analyze, and optimize sewer and stormwater systems with confidence.

Contact us today to learn more.