The country’s population is expected to hit eight million by summer’s end.
Maria Lezzi, director of the federal department of land management, says the Swiss have room for between 1.4 million and 2.1 million more residents without changing zoning rules.
Housing to accommodate the extra residents could be built without cantonal approval or need for changes to municipal plans, Lezzi told the Sonntag newspaper.
The numbers are strictly theoretical, she cautioned in an interview.
But Lezzi told Sonntag that the popular initiative backed by voters to limit the number of secondary homes is a “clear sign” of the resistance by the Swiss to unchecked growth.
The large number of rezoning proposals rejected by municipal councils is another indicator of such opposition, she said.
Lezzi acknowledged that the cantons and the federal government have made planning mistakes.
Better “spatial planning” is urgently needed to curb urban sprawl and to preserve quality of life in many Swiss regions, she said.
If growth of settlements continues unabated, large parts of Switzerland will become “faceless”, Lezzi charged.
“This not only affects quality of life but also entrenched economic interests, such as tourism.”
The federal government is currently working on a new planning act, approved by parliament before the summer recess.
The legislation gives Bern the power to sanction cantons that fail to act against unchecked growth and to combat sprawl.