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Storm Systems - Channels, Municipal Drains, Dams and Dykes

The City of London has many other systems that help drain and control the rainwater. These systems, including storm sewers, help drain rainwater away from developments, businesses, industry and recreational areas of the city. Some of these systems are:


Open Channels

Open channels are natural or engineered streams, waterways,  that are typically used to convey base flows, minor and major storm events to tributaries and watercourses.  In some cases, the open channels are designed to provide flood and erosion control detention during storm events.


Municipal Drains

If you own property that has a municipal drain and need more information such as, what is a municipal drain? How does it affect me?  and What will it cost?, please visit the Ontario Ministry of Agriculture and Food website to find out more about Municipal Drains.



A dam is a structural barrier in which it's main purpose is to slow down and detain water to help control downstream flooding. Sometimes a dam's secondary purpose is to produce hydro power. The City of London has one major dam (Fanshawe Dam) and it is located in the Fanshawe Park Conservation Area at the east end of the City. 



Dyke structures (also known as levees) are used to manage or prevent water flow into specific land regions. There is an extensive network of dykes designed to protect the city of London from flood damage. As of 2006, there are approximately 5.5 km of dykes:


  • around sections of the north, south and main Thames River
  • Along the south branch are the Clarence and Ada Jacqueline dykes
  • Along the main branch are Riverview, Byron and Coves


The West London Dyke (WLD) is the largest. It runs along the north and main branches at the forks.

The Broughdale Dyke is on the north branch. 

The majority of the dykes within the City are earthen fill dykes.  WLD is constructed using reinforced concrete panels and has been restored and replaced in some sections with a flood wall.

The Coves contains a flap gate that is used as a stormwater management release structure.