2011 Richelieu river flooding
Richelieu valley map The 2011 Richelieu river flooding is a current disaster. See Wikipedia (French) for details and news. OpenStreetMap has good map data in this region, but street names are not specified.
The May 2011 Richelieu River Basin flooding is due to exceptional snow accumulations, rains and recently strong winds in the Lake Champlain and Richelieu river basin. A record high water level have been registered in May 6. And a new record in may 23. More then three thousand houses are surrounded by water and hundred of houses have been evacuated.
Eighteen municipalities are mainly affected. The affected zone extends around 1 km each side of the river in low lands.
Many volunteers are building dikes around homes. The next steps will be to pump water from the houses basement and proceed to clean the land and repair the houses.
Openstreetmap mappers can help in producing maps with streets index of affected zones. Mapsomatic will undoubtedly be useful to produce such maps. However, many street names are not indicated presently on maps OpenStreetMap.
Map of the flooded zone in Richelieu River
Map of the flooded zone (markers flood polygon overlayed on google) has been prepared by La Presse newspaper in Montreal in early may (not available anymore).
A Revised Map of the flooded zone (flood polygon overlayed on Openlayers) has been prepared by Pierre. Ikonos and WorldView-1 Satellite imagery are provided by Ministère de la sécurité publique du Québec.
OpenStreetMap Resources for use by activities on the ground
Work have been started to delimit the flooded zone in Openstreetmap. The following tas have been used
- note=temporary; richelieu river flooding may 2011
Pierre has produced ways and relation to document Richelieu River flooding.
Affected zones (These will be revised when he obtains more detailed information on streets / areas affected):
Boundary relation that could be used to produce Indexed map of streets with tools such as Maposmatic
MapOSMatic maps with street indices
- Here is an example of MapOSMatic output on a largish area that includes the center of Saint-Jean-sur-Richelieu : .
- Another example that includes the Saint-Jean-sur-Richelieu / Saint-Eugène affected area defined above : 
These example maps should be generated again when the OSM database will have been updated with more street names. Other maps covering the affected zones defined above could also be produced on MapOSMatic and linked from here.
Data sources and imagery
- CanVec data set contains street names. The flooded zone is part of two NRCAN tiles coded 31H3 and 31H6. Canvec data (osm format) for 031H tiles is available on NRCAN site at the following url : ftp://ftp2.cits.rncan.gc.ca/osm/pub/031/H/ . For import coordination, you can use #osm-ca IRC channel on irc.oftc.net, and this shared online spreadsheet.
- Street map of the city of Saint-Jean-sur-Richelieu
- Yahoo has high resolution imagery of Richelieu river from Saint-Jean downstream to Saint-Laurent river.
- NASA Earth Observatory has images of flooding along the Richelieu River. They are also available as WMS/TMS. And this web interface shows them with OSM maps.