Builders may be blocked in Snowdonia National Park row

A row over properties at Snowdonia National Park could see builders blocked from tweaking planning applications during big developments.

Developers were given permission to build 401 houses on 29 acres of national park land at Balkan Hill, Aberdyfi, in 1967. A series of tweaks to the plan were made in the years that followed.

Hillside Parks Ltd, a developer that now owns the site, brought a claim against the Snowdonia National Park Authority, the local planning authority, in 2019 to confirm that the original scheme could be lawfully completed despite these tweaks.

The authority successfully argued in the High Court and Court of Appeal that it could not, as permissions granted after 1967 were inconsistent with the original plan. Roads had been built in places originally earmarked for housing, and vice versa, it said. Hillside has now been given permission to appeal the decision at the Supreme Court, with the case due to be heard in July.

The case raises the issue of whether a planning permission already granted is nullified if subsequent tweaks, known as drop-in planning applications, are approved.

If Hillside loses at the Supreme Court, this could set a legal precedent, which means developers who use drop-in planning applications risk invalidating the original plan.

It could lead to planning permissions needing to be decided in full at the start of projects, and any deviations could end up causing huge delays or even mean the whole plan collapses.

Snowdonia National Park Authority declined to comment.

Hillside Parks Ltd was contacted for comment.