At least half of the shellfish harvesting zones in the Ria Formosa near Olhão have been reclassified as 'Zone B', which allows the sale of seafood after it has been purified.
The B classification now covers another 30% of the shellfish nurseries that has been downgraded by a government edict in response to an EC analysis of the water that showed high levels of pollution.
This means that the harvesting areas with a good rating will rise to 80% later this month or in early February.
This reverses the situation created by the government decree issued in December 2013, which ruled that 80% of the production areas of the Ria Formosa could not provide shellfish for sale to the public. This would have had a devastating long-term affect on those that rely on this trade for their livelihood, some 2,000 workers.
The announcement of the reversal was made by the mayor of Olhão, António Pina, at a meeting with industry representatives and fishermen in Olhão.
These changes are considered a great victory by the leaders of the associations representing the sector, but they say this should not stop them fighting for a reclassification of the remaining areas.
This reclassification is supported by the analysis of new water samples that have been taken, but one zone remains a serious problem, lying as it does between two notorious sewage outfalls.
Mayor António Pina assured the fishermen that action was being taken to stop this pollution problem by the construction of a new sewage treatment plant and sorting out the waste water outflows in the town itself.