From Le Provençal

Pollution in the Sorgue River had reached such
proportions that the river fauna and flora were threatened. Faced with this
alarming situation, an association was formed to fight against this pollution.
This is the "SOS Canal de Vaucluse, Sorgues et Environnement,"
presided over by Mr. Gaston Manuel, former mayor of Ther. "This pollution,"
Mr. Manuel explained, "is essentially caused by industry, particularly
the paper mills, whose effluent silts up the river, one of the most beautiful
in the region. It is a prized site for trout fishing." But we can legitimately
ask ourselves how long the trout can survive under such conditions. The
Vaucluse Canal is one of the branches of the Sorgue which receives effluent
from three factories, the Papeteries de Provence, the Peaudouce and the
Scop de Gromelle.
As recently as two years ago, studies showed
that the Sorgue contained zones where the level of heavy metal pollution,
notably by aluminum, was 15 times above the authorized level. The presence
of a great deal of oxygen-absorbing organic material was noted, making aquatic
life impossible.
Limit the damage

The publication of these statistics had already
provoked a reaction from the industrialists, who had either restarted their
purification plants or connected to the public plants. But this was not
enough, and in certain zones the saturation limit persisted. Immediate intervention
was essential to limit the damage. The "SOS Canal de Vaucluse"
association therefore conducted a test , which could later be applied to
the whole river system if the results were as conclusive as hoped.
The experiment was carried out by Mr. Thierry
Arnaud, a native of the region, a hydrobiologist who directs an environmental
research and study center in Haute-Savoie.
Bacteria digested the silt

Mr. Arnaud explained that the experiment was
a pilot-test, using mineralizing bacteria of natural origins, known as Alken
Clear-Flo®. The bacteria increased in concentration on the river
bed and transformed the organic material into mineral elements which then
restarted the biological cycles.

The river was seeded with 500 kilos of selected
mineralizing bacteria over 306 meters of river. The bacteria literally digested
the silt and returned the Sorgue to its original clear condition.
After three months, organic matter was reduced
more han 60 cm in particularly polluted areas without any upset of the ecosystem
at the physio-chemical or biologial level. Both BOD and COD were lowered
and stabilized. Gravelly surfaces, appropriate for fish spawning, reappeared.
Once the treatment program was completed, the river continued to improve,
proving that it had regained its capacity for self-purification.