Really there's a referendum on all big projects? Is this governed by a certain threshold i.e above amount X it gets put to referendum? That's pretty awesome if so. In the US this done in a back room away from public view it has various names - pork barrel politics, horse trading, etc. And such allocations are often tacked onto other legislation that might have nothing to do with the project.
On a cantonal level there is (among others) a "finance referendum". This may be mandatory or optional depending on the canton. Optional means the project is only actually put to a referendum if an eligible group demands it. An eligible group may be a political party, a certain number of voters, certain interest groups, etc.
For example in the Canton of Zürich there is an optional referendum on decisions of the Cantonal Council on new non-recurrent expenditure of more than 6 million francs or new recurrent annual expenditures of more than 600'000 francs. To actually put such a decision to a referendum requires either 3000 voters (public referendum), 12 municipalities, the city of Zürich or the city of Winterthur (municipal referendum), or 45 Cantonal Council members (cantonal referendum).
On a federal level there is no "finance referendum". It has been proposed, but most political parties are against it since it could hinder the Federal Council in its freedom of action and delay or even block important investments. But there's a mandatory referendum for all constitutional changes and certain other things like joining supranational communities etc. and a optional referendum for all federal laws and certain other things like international treaties etc. The optional referendum requires 50'000 voters (or eight cantons, but this only actually happened once).
"Switzerland's voting system is unique among modern democratic nations in that Switzerland practices direct democracy in parallel with representative democracy. That's why the Swiss system is called semi-direct democracy.[1] Direct democracy allows any citizen to challenge any law approved by the parliament or, at any time, propose a modification of the federal Constitution.
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Approximately four times a year, voting occurs over various issues; these include both initiatives and referendums, where policies are directly voted on by people, and elections, where the populace votes for officials.
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