In decision 1C_209/2025, the Swiss Federal Supreme Court upheld a planning zone at the Zurich lakeside in Wollishofen. The key issue was whether the 2016 revision of the zoning ordinance barred a renewed planning review.
The Court clearly rejected this argument. What matters is not the formal age of the plan, but its substantive content. In the area concerned, the 2016 revision merely introduced technical adjustments and did not amount to a genuine planning reconsideration. At the same time, the applicable special building regulations date back to 2009 and are therefore approaching the end of the typical 15-year planning horizon. In addition, new legal requirements and planning policies—particularly regarding public access and ecological design of lakefront areas—justify a reassessment.
Against this background, the threshold for imposing a planning zone remains low: it is sufficient that a revision of the planning framework is seriously contemplated and not obviously unlawful. The merits of the future zoning solution are not examined at this stage.
For practitioners, the message is clear: planning zones are difficult to challenge, and the principle of plan stability offers only limited protection in early planning phases. Substantive legal scrutiny is effectively shifted to the subsequent zoning procedure.