Environmentalists are taking on Slovenia's government, forcing through a referendum on water rights.
The vote comes after the parliament approved amendments to a water law in March, which opponents fear will damage the country's coast, lakes and river-sides and increase water pollution.
"The Slovenian government wants to build different buildings on the water shore, and we believe this is damaging the right to drinking water. And we decided that we will do anything (so) that this law won't be accepted."
Speaking for a civil society group, Nika Kovac said the grass roots campaign is powered by ordinary people.
"The campaign was made by the people, by the people in different cities, in small villages, on the street. They were writing letters to their neighbours, they were giving leaflets, they were speaking with people. And I believe in power of people and I hope that there will be enough of us."
In 2016 Slovenia amended its constitution to make access to water a fundamental right and halt its commercialization.
Environmentalists fear construction will limit public access, while increasing the risk of water pollution and threatening the quality of drinking water.
The government insists the amendments will raise funds to protect waterways, strengthen flood defences and tighten construction regulations.
The nationwide vote will be legally-binding and will require a majority of those who vote and at least 20% of eligible voters to reject the amendments.