The Water Convoy, which arrived in Paris on Saturday, brought together a thousand people on the Champ de Mars and then in a procession through Paris to denounce government plans to build mega water reservoirs used for agricultural irrigation.
Over 1,000 people marched across the French capital to protest the environmental impact of mega water basins used by the agricultural industry.
"Grille by grille, tarpaulin by tarpaulin, we'll destroy all the reservoirs", sang the demonstrators, who arrived in the early afternoon from Orléans, where they had been stationed since Thursday in front of the headquarters of the Loire-Bretagne water agency.
A delegation had been received for more than five hours the previous day by Sophie Brocas, the prefect of the Centre-Val de Loire region and basin coordinator, to call for an unsuccessful moratorium on current basin projects.
"We're very upset because we didn't get the moratorium we came for. We're going to have to continue our actions to dismantle the construction sites", said Benoît Feuillu, spokesman for the Soulèvements de la terre movement, to applause on Saturday.
He did not give any dates for these actions, but said that "the next meeting would take place in Niort on 8 September, for the trial of nine representatives" of environmental and trade union movements "accused of organising banned demonstrations".
The procession gathered on the Champ de Mars, before making its way to the Eiffel Tower. The protestors moved with the aim of reaching the town of Montreuil, east of Paris, for a "festive evening" as part of an environmental festival.
However, the police blocked the bridges, their buses channelled the flow of demonstrators, who set off on the quays of the capital, to the sounds of musicians.
Meanwhile, traffic was eventually severely disrupted.
Some demonstrators unfurled a banner on a bus full of tourists, surprised but amused by the scene.
Mega-basins store water drawn from the water table in winter, in the open air, in order to irrigate crops in summer when rainfall is scarce.
Their supporters see it as a condition for the survival of farms in the face of the threat of recurring droughts.
Opponents, on the other hand, denounce a "monopolisation" of water by the "agro-industry" in a time of climate change.