Satellite flood mapping service strengthens eastern France civilprotection (Forwarded)

ESA News
http://www.esa.int

20 March 2006

Satellite flood mapping service strengthens eastern France civil
protection

A satellite-based rapid mapping service developed to support civil defence
activities in eastern France is ready and on call 24 hours a day, seven
days a week. The pioneering service has been designed to manage flood
events -- the world's most widespread category of natural disaster.

As well as being applied to risk assessment and prevention efforts, the
ESA-backed Flood Plain Monitoring Service aims to deliver map products to
end users within six hours during times of crisis, giving emergency
responders the ability to track the full extent of floods as they occur.

Developed over three years through the ESA Earth Observation Market
Development (EOMD) programme, the service was consolidated with the
France's Eastern Defence Zone (EDZ), which is made up of 18 departments
with a total area of 105 000 sq. km and a population of 8.3 million
people. It also includes four major hydrological basins potentially
vulnerable to flooding. The service provider is Strasbourg*based rapid
mapping specialist firm SERTIT, with the EDZ Prefecture as partner
end-user.

"We are one of France's seven national civil defence zones," explained
Colonel François Maurer on behalf of the French Directorate of Civil
Defence and Security (DDSC), Chief of Staff (Chef d'état-major) of the
EDZ.

"Our role is to carry out emergency planning, and, in the event of an
incident, coordinate the response activities of the various departments.
Department prefects are the main decision makers who activate the
emergency services but may not have specialist knowledge in the field, so
we advise them as needed."

The service is based on two types of satellite data. High-resolution
imagery from optical satellites is combined with satellite radar imagery
which can be acquired even at night or through heavy cloud or rainfall.

The large amount of detail found in optical images is used in advance to
create reference land cover maps that can be combined when needed with
radar images that are highly sensitive to waterlogged surfaces. These
images can also be utilised in conjunction with digital elevation models
(DEMs) derived from radar data to help model which areas are most at risk.

"We don't mind which satellites are used, we just want the maps," said
Colonel Maurer. "Our key issue is time -- but very quickly the satellite
maps give us an impression of the flood extent, and the areas that are
affected. The maps can support high-level decision making and the best use
possible of human and material resources.

"We can interpret them to see the extent to which the water is going to
extend, to help steer our teams around and figure out where best to deploy
our pumps and sandbags, where to evacuate first. New buildings may not
have made it yet onto standard paper maps, but might still need priority
evacuation: hospitals, for example, or homes for the elderly. It is better
to perform something like that well in advance rather than when feet are
already in the water!"

The service was initially designed for flood crisis mapping, but it was
soon realised the products would also be relevant for other flood
management phases: the post-crisis clean up, prevention and forecasting.
Some 80 agencies involved in flood management within the EDZ -- such as
regional water agencies and flood forecast services -- have therefore been
briefed on utilising the service.

During the last decade floods have affected approximately 1.5 billion
people -- more than 75% of the total number of people reported as affected
as natural disasters worldwide. They are catastrophic events affecting
large areas at once, which can make them difficult to predict and monitor.

Traditional flood forecasting is carried out using river height and
rainfall measurements -- often only sparsely available -- assimilated into
hydrological models. Flood extent is often calculated through historical
analysis of maps of past events, or model calculations. 'Real-time' flood
measurements, if made at all, are carried out through expensive and
weather-dependent aerial photography campaigns. Post-crisis damage mapping
traditionally relies on ground surveys, projections from population
statistics and insurance damage claims.

"One of the objectives is to keep detailed satellite-derived maps of past
flood events and their evolution, to build an accurate memory of what has
happened across our area of interest," added Colonel Maurer.

The Flood Plain Monitoring Service has yet to be used in a flood situation
within the EDZ, although satellite images are regularly acquired for
reference mapping and risk analysis. SERTIT has carried out crisis mapping
for a number of flood situations further afield, in locations from Germany
to China, often in support of the International Charter on Space and Major
Disasters, which prioritises the acquisition of satellite imagery for
disaster relief operations.

"The use of satellite imagery has recently been added to the operational
Civil Protection procedures," concluded Colonel Maurer. "This integration
represents a big achievement for the three years of our activity, and
shows how the demand for this type of data is here to stay."

This achievement has led to the rapid mapping service continuing its
development within the framework of ESA's Earthwatch GMES Services
Elements (GSE), Risk-EOS and Respond, responding to natural disasters and
humanitarian aid situations worldwide providing services to the
humanitarian aid community to civil defence agencies.

This activity has been carried out as part of a Flood Plain Monitoring
project within ESA's EOMD Programme, aimed at strengthening European and
Canadian capacities for the provision of geo-information services based
mainly on Earth Observation data. To find out more about using Earth
Observation for flood mapping, or further opportunities with EOMD, please
contact eomd @ esa.int .

Related news

* Dragon over water: Envisat monitors China's largest lake, rivers
flooding
http://www.esa.int/esaCP/SEMKDKTLWFE_index_0.html
* Central European flood surges watched from orbit
http://www.esa.int/esaEO/SEMFGX95QCE_index_0.html
* Disaster Charter brings satellites to bear on Romanian flooding
http://www.esa.int/esaEO/SEM20J808BE_index_0.html

In depth

* Earth Observation Market Development (EOMD)
http://www.eomd.esa.int/
* International Charter on Space and Major Disasters
http://www.disasterscharter.org/
* GMES
http://www.esa.int/esaLP/LPgmes.html

Related links

* SERTIT
http://sertit.u-strasbg.fr/
* French Department of Civil Protection
http://www.interieur.gouv.fr/rubriqu...nse_secu_civil

[NOTE: Images supporting this release are available at
http://www.esa.int/esaCP/SEMWMDMVGJE_index_1.html ]