New flood maps released for 2008 and 201814 August 2020
FREDERICTON (GNB) – The Department of Environment and Local Government has used the latest technology to create a 2018 flood map, the worst recorded flood in the lower Saint John River basin. The 2008 flood map has also been updated to more accurately reflect historical flooding, also in the lower basin.
The 2018 map was completed by dividing the entire Saint John River into 83 sections and applying maximum water levels to each of those sections.
Data from water level gauges stationed along the river as well as the Hydrology Centre’s hydraulic model currently used for flood forecasting were analyzed.
In addition, a survey team was sent out in 2019 to verify peak flood levels and confirm the accuracy of the Hydrology Centre’s modeling. Aerial imagery of the 2018 flood was also used to validate the extent of flooding.
“We are committed to providing timely and accurate information so that people and organizations can plan and prepare for future floods, protecting their health and safety,” said Environment and Local Government Minister Jeff Carr. “The more accurate and update-to-date information we have, the better positioned we are to make informed decisions quickly.”
A similar methodology was used to update the 2008 map, focusing on the area from Mactaquac to the Bay of Fundy, where flooding was the worst. Although the province experienced significant flooding in 2019, it was not to the same extent as in 2018 so a map for last year was not completed.
The new maps do not account for future potential flooding resulting from climate change and they do not reflect the risk associated with one-in-20-year flooding or one-in-100-year flooding frequencies. Flood hazard maps are being developed under the Climate Change Action Plan and work on this initiative is ongoing.
Both maps are available at GeoNB.