Bishop's Falls, January 1983

Flooding is part of the natural environmental processes. It is often caused by heavy rainfalls in combination with rapid melting of snow on the ground. Other causes of floods include ice jams in rivers and high tides with storm surges along the coast. Flooding is essential for a healthy ecosystem, however, human encroachment on the flood plains of water bodies means that flooding also causes human hardship and economic loss. Flood damage is an increasing problem in Newfoundland because of increasing population density around water bodies and the higher values of water-front property. More than 57 communities in the province have been affected by flooding which has caused over $40 million in damage over the past 15 years.

In Newfoundland, we try to discourage flood-vulnerable development on flood plains. The province, in cooperation with the federal government, undertake hydrotechnical studies and mapping of flood risk areas. The maps, completed for 38 communities so far, delineate the flood risk zones for floods with a return period of 20 years (5% chance in any year) and 100 years (1% chance in any year). These maps are used for public information, municipal planning, development control, and the setting of structural design criteria. All proposed developments in flood risk zones are evaluated against potential impacts on water resources, the structures themselves, and the surrounding areas.

The public information versions of the flood risk maps presented on these pages are suitable for general reference only.  More detailed flood risk maps for use by municipal authorities, developers, planners, consultants  and other government agencies are available by  contacting the Division.

The maps in the table below are in JPG image and Adobe PDF format. The JPG images are viewable directly in your browser or an image viewing program. The Small JPG files are approximately 800x530 pixels and 80 Kb in size. The Large JPG files are about 1550x1024 pixels and 260 Kb in size. The PDF documents are in Adobe PDF format and, if you have an older browser, may require the free Adobe Acrobat Reader for viewing. The PDF documents offer the most detailed resolution and are about 1.1 Mb in size. If you right click on any of the links below and select the "Save as" option you can download that file to your computer for later viewing.

These maps are also available from the Department as 2ftx3ft folded paper maps and please contact us if you wish to obtain a copy.

We have also made progress in flood preparedness through the establishment of a provincial flood forecasting centre, in particular, for the communities of Steady Brook, Deer Lake and Badger. Precipitation, temperature and flow data are remotely collected from rivers and downloaded to our computers in St. John’s in near-to-real-time via satellite. Here, using state-of-the-art technology in hydrologic modelling, hydraulic modelling, and data management, as well as local observations, we determine forecasts of river flows and water levels for several days. The information is relayed to the provincial Emergency Measures Division for appropriate action as may be necessary in a potential flooding situation.

In the longer term, we undertake flood studies and investigations. These involve collection of hydrologic and hydraulic data, selection of appropriate design philosophies, modelling, post-flooding assessments of damage, and analysis of results. The studies and investigations lead to recommendations for flood control strategies, remedial measures and new flood forecasting systems.

Flooding is a natural event, but its often devastating effects on our lives and properties, can be minimized by proper planning, state-of-the-art flood forecasting systems, and appropriate flood control strategies.

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