Facts
The F. AG, operator of the Seedamm-Center shopping centre in Pfäffikon (Schwyz), submitted a construction application on 21 July 2016 for a direct access to the centre via a high bridge from the motorway junction Pfäffikon (Nationalstrasse N03). The project included the conversion of the existing Pfäffikon junction with horizontal and vertical shifts of the carriageways as well as the construction of a 160-metre-long high bridge. The Federal Roads Office (FEDRO) approved the project as the owner of the land, but required a usage approval and agreement before construction could begin. The appellants 1 (A. and others) and the G. AG lodged objections against the construction application. The municipal council of Freienbach granted the construction permit subject to conditions, whereupon the appellants filed an appeal with the Government Council of the Canton of Schwyz. This dismissed the appeals, as did the Administrative Court of Schwyz in the second instance. The appellants then filed an appeal in public law matters with the Federal Supreme Court (procedural numbers 1C_787/2021 and 1C_9/2022).
The project envisaged a fundamental redesign of the existing motorway junction Pfäffikon through the construction of new carriageways, retaining walls, drainage systems and safety equipment. The total costs amounted to around 21 million Swiss francs, with the majority allocated to the conversion of the junction. The Federal Office for the Environment (FOEN) classified the project as a substantial modification within the meaning of Art. 8 para. 2 Noise Abatement Ordinance (NAO), as the structural substance would be significantly altered. In 2014, FEDRO withdrew an earlier planning approval application because the canton had not fulfilled its planning obligation for cantonal connecting roads. The [F. AG] then continued the project alone.
Considerations
The Federal Supreme Court first examined the applicability of the National Roads Act (NHwA) and the National Roads Ordinance (NHwO) to the project. According to Art. 21 NHwA and Art. 23 et seq. NHwO, construction projects involving far-reaching interventions in the structural substance of existing national road components require a federal-level planning approval procedure. The existing Pfäffikon junction is to be classified as a component of the national road (Art. 6 NHwA, Art. 2 lit. c, g, h and i NHwO), as it serves to connect the N03 with the local road network. The planned adjustments – in particular the horizontal and vertical shifts of the carriageways as well as the construction of new retaining walls and drainage systems – do not constitute a mere redesign in the area of the national road, but rather a modification of the national road itself. Such modifications are subject to mandatory federal planning approval procedures and cannot be approved in cantonal or municipal construction permit procedures (paras. 4 and 5).
The high bridge is to be classified as an indispensable component of the execution project, as it is functionally and structurally linked to the conversion of the junction. Without the high bridge, the planned adjustments to the junction would be pointless, and conversely, the bridge depends on the existing motorway junction. An isolated approval of the bridge as a third-party project within the meaning of Art. 44 NHwA and Art. 30 NHwO is ruled out, as it would impair future expansion of the N03. Moreover, the bridge does not serve exclusively private interests, but also public concerns such as relieving the local traffic network and reducing congestion on the motorway (para. 6).
The Federal Supreme Court emphasised that the provision in Art. 30 NHwO, which merely requires FEDRO’s approval for…