MontstMichel.co.uk 2010
Web site design by Private space 2010
The Bay
at Le Mont Saint Michel
The Bay
The Bay
For many years, the bay around Mont saint Michel is considered a must see
and a place to be explored when visiting the Mont. However in recent years the bay
has become important for more than just tourist and sight seers, since the arrival
of ecology scientific studies that have been carried out all over the bay due to
the bays surprising natural phenomena.
The Tides
Low tides and High tides more or less
constantly vary from a few centimetres to quite a few meters,
There is in no other
place in the world apart from for the Bay of Fundy in Canada, where the tides differ
as much as at Mont St Michel where the variation between low tide and high tide can be to
the extent of fifteen meters.
Due to the pull of gravity exercised by the moon and
by a less amount by the sun on the oceans, of the world the tides rise and fall two
times in every lunar day of 24 hours and 50 minutes. When the sun, moon, and the earth become
aligned, or are close to this alignment an astronomic phenomenon known as syzygy
takes place. The draw of the two celestial bodies, together, provokes extremely strong
tides, known also as the spring tides. This phenomenon is mainly apparent through
the spring and autumn equinox, but more spectacularly at the times of the new and
full moon. High tides surround saint Mont Michel around every seven solar hours,
eight hours in winter and nine at summer time.
The extraordinary tides in the bay
of Mont-Saint-Michel are because of its geographical location. The movement of the
tide, coming in from the Atlantic sea, hits the Cotentin coast (Cotentin coast is
part of the Normandy coast line) like it’s a wall, and the tidal water breaks on
the coast before going in to the bay which is half bowl shaped. In this virtually
level area, it is apparent that a range of fifteen meters turns into a huge distance.
In periods of the spring tide, the low tide goes out as far as 18 kilometres from
Mont-Saint-Michel. The flood tide of the sea, which once rose into the Couesnon River,
could be seen as far as Antrain a department of Brittany, more than 20 kilometres
inland. The tides consequently went inland as much as 40 kilometres, a distance covered
by the sea in no more than six hours. Not possibly with the speed of a galloping
horse, as told in wives tales, but all the same somewhat remarkable. The haste with
which the tide moves is the major danger in the bay where misfortunes infrequently
occur. A stroll along the beach conceals could lead to unforeseen hazards for any
person which neglects to learn in advance just when the high tide will come in and
even how high it's going to go, and even for any person who does not make certain they
are back at the Mont sixty minutes or at least an hour and a half prior to high tide. It really is
almost hopeless for any person on their own to flee from the currents and whirlpools
which characterize the tides.
This kind of serious hazard is flanked by that of the
quicksand’s, consciously exaggerated through legend. The deviations of the coastal
rivers into the bay have left behind them old water holes filled with fine sand in
suspension, covered by some sort of weak dry crust, which may quickly cave in beneath
the weight of any person. In fact, the actual quicksands tend to be much rarer than
history might guide someone to believe. Neither should they be mixed up with all the
levels of mud, a slimy build up of fine sand as well as fine clay that makes up one
of the sedimentation levels of the bay. So remember when visiting the bay to keep an I on
the tides.
Silting
Within the bay, of Mont-Saint-Michel the occurrence of sedimentary build up is
speculated that the progressive silting will course an upward build up of land that
might before too long endanger the maritime personality of the bay. At first look,
it would appear to be a natural motion, typical to all bays of the world. The flooding tide is
more powerful compared to the ebb tide which means that a lot more alluvial earth is
brought in than out. This particular alluvial earth left by the sea fills in the
anfractuosities of the shorelines, gulfs plus bays. All-around Mont-Saint-Michel
the amount of sea deposits is estimated being close to three hundred thousand cubic
meters annually.
Typically the lighter in weight particles are usually deposited close
to the shoreline, where they form muddy sand (called ‘tangue’) that includes a combination of really fine particles
of clay, delivered down through the coastal rivers, as well as small fragments of
sea shells. At one time, this particular greyish sludge had been used to fertilize
the nearby lands.
Once deposits introduced by the ocean have elevated the amount of
the land sufficient to put it out from the reach of tide, plant life that will be
able to endure large proportions of sodium (salt) eventually begin taking hold, to
begin with saltwort along with sea-fennel. An area is actually consequently established
which the occupants of Mont-Saint-Michel name ‘herbu’ (grassy) much better recognized
with the rest of the planet as salt marsh. This type of plant life subsequently helps
to retain the sea sediments, accelerating the process of silting. For hundreds of
years, the bay of Mont- Saint-Michel seems to have prevailed in avoiding this unique occurrence.
The presence of various water ways down the coast of the Couesnon, the river of Ardevon,
the Guintre, the river of Huisnes, the Selune and the See, alongside the array of
tides reveal the reason why. Each one of these rivers, no greater than a rivulet
in the period of neap-tides, became a hastening flow when the tides permeated inland
and flooded huge regions of swampland. At low tide the particular, substantial masses
of water formed and went back towards the ocean, creating extraordinary waterfalls
that swept the bay clear of all of the debris remaining from the high tide. The change
of these waterways in the direction of the bay occasionally carried them up to the
coast where they are able to significantly ruin crops. Tradition narrates that numerous seaside
villages vanished totally during the Middle Ages. The very first attempts to be able
to transform the fertile muddy sand of the bay into arable terrain date towards the
eleventh Century, around the beginning of the Thirteenth century, the bishop of Dol
requested numerous dams to be built which could protect the black swamps from the
ocean also the rivers. Mont- Dol, that at one time raised upon the timeless sand just
like Tombelaine and Mont-Saint- Michel, found itself enclosed by land. Up until the
finish of the Nineteenth century, however, the location between the rivers, See and
Couesnon continued to become at the mercy of powerful currents that made it impossible to build polders
and reclaim the land.
The concession granted Mosselman and Donon within 1856 was a
turning point in the history of the bay. Because of the modern methods imported from
the Netherlands, the Couesnon was canalized approximately less than 2 kilometres
from Mont-Saint-Michel. The waterways See and Selune were deviated northwards because
of a submarine dam, established on the rugged point of Roche-Torin, also the several water
ways that previously ran in to the Couesnon also the Selune had been additionally redirected here. Protected
from the deviation of the waterways, the base of the bay therefore grew to become
a massive compartment for sediment.
The constructing of a causeway in 1877, regardless
of resistance from the State Authorities of Fine Arts, has been one more phase in
the polderization that was concluded within 1936. The Association of the Friends
of Mont-Saint-Michel had been arguing for 15 years to keep the Mont an island, even
though they were not successful in stopping work on the causeway, they succeeded
in obtaining the community forces to be able to restrict the actual arable lands
to no nearer than one and a half kilometres from the Mont.
The development of brand
new polders had been therefore discontinued permanently. Yet this didn't get rid
of the modifications that had been made to the rivers within the bay, the main reasons
for the silting up. Certainly the grasslands nevertheless continued increasing in
the direction of Mont-Saint-Michel. Scientific studies were started in 1974 in an
attempt to discover away that may enable Mont-Saint-Michel to sustain its ocean going personality without
infringing on the legal rights acquired by the farmers of the polders. Backed by
the Central Hydraulic Laboratory, all of these scientific studies have shown that
it was achievable to reduce the level of the sands through putting back the water
holes, which, up to the Nineteenth century, had kept the bay by natural means clean.
The
technicians specified plans for 3 stages: first, the basin of the Couesnon needed
to be controlled so that the tide seas could flow to the lower course of the river
and constitute a basin which would quickly empty with the ebb tide. The 2nd stage offered
was for the creation of a number of man-made tide reservoirs, which would perform on
the same theory, towards the east of the causeway. The 3rd stage comprised in the
dismantling of the dam of Roche-Torin, in order that the See and Selune rivers could deepen the
eastern area of the bay.
Work started in 1983 on the 3rd stage, which was the easiest
from the technological and juridical perspective. The regulation of the Couesnon
basin will be carried out pretty shortly}, in the hope that the pessimistic prediction
of the Central Laboratory of Hydraulics that the point of no return was reached in
1991.In more recent times the new Couesnon dam was finished in 2010 and there is
now plans on removing the causeway which was built in the late 1870s. Now only time
will tell if all this work will reduce the current silting.
The Wild Life Of The Bay
The dredging of the area will certainly have an effect on
the wild life of the bay, the reduction of the meadow zones and as a result the number
of sheep that graze on the salt marsh. This unique race was selectively bred in the
Avranchin in the Nineteenth century and can be very easily recognized by the form
of the head and the dark coloured legs. Feeding upon these types of grasslands, their
tasty meat is famous and appreciated in areas faraway from Mont-Saint-Michel.
The
wildlife, which is made up mainly of wild birds, is a lot more heterogeneous. The
bay constitutes a perfect sanctuary for migratory birds, particularly the anatides that
spend the winter months here. There's also several ducks, prevalently mallards but additionally rarer
varieties such as the Sheldrake’s of Belon, which nest about the polder dams and
the reefs of Tombelaine. With a little good luck, watching the shore it may also
be possible to see a barnacle-goose or perhaps some other type of wild bird. Whilst
these types of migratory birds winter here, there are others for whom the bay of
Mont-Saint-Michel is but a way station: herons, pink flamingos, and more rarely a
wild swan.
By far the most numerous, however, are those birds whose natural environment is
the bay. All sorts of gulls, sea swallows, and even an occasional big cormorant.
The
bay is also inhabited by additional wildlife but they are more challenging to see the
fish, primarily grey mullet, flounders, bass. In the Nineteenth century, fishing
had been one of the principal actions from the occupants of Mont-Saint-Michel while
the ladies collected the small clams which resided within thick banks in the sand.
So we can only hope that the wild life of the bay will adapt to these changes well.
Photo of Mont Saint Michel And its Bay
Photo of the Bay
Photo of the effects of Silting
Photo showing sourounding water ways of the bay
Photo of the Couesnon River msm in the back drop
Photo showing construction of the new dam
Photo of the new Couesnon dam
Photo of the Avranchin sheep
