D-CLEAN in South Transdanubia, Hungary

D-CLEAN pilot area feature | Hungary, South Transdanubia

In the rolling hills of southwestern Hungary, five small villages are showing how wastewater management can be adapted to rural realities. South Transdanubia is one of the D-CLEAN pilot areas, where nature-based solutions will be tested on the ground.

A hilly region west of the Danube

South Transdanubia is a hilly region in southwestern Hungary, stretching west of the Danube across the counties of Somogy, Baranya and Tolna. In this rural landscape, five small settlements currently lack a sewage network and wastewater treatment systems: Beleg, Kisharsány, Nagytótfalu, Oroszó and Ráksi. Beleg and Ráksi lie in Somogy County; Kisharsány, Nagytótfalu and Oroszó in Baranya County.

There is no sewer network and no wastewater treatment plant in the pilot area. The only existing facility of this kind is a stormwater drainage system in Oroszó, with an approximate length of 3,131 m.

Why nature-based solutions fit here

The villages have small populations spread over large areas, so building a conventional sewer system would be very costly and inefficient. Nature-based wastewater treatment offers a smart and affordable alternative that works with the local landscape.

The close proximity of Kisharsány and Nagytótfalu also opens opportunities for shared solutions, while tailored approaches are needed for the more remote settlements. Together, these communities show how sustainable wastewater management can be adapted to rural realities.

Part of a bigger picture

D-CLEAN, Improving Water Quality in the Danube River Basin: Nature-Based Solutions for Sustainable Wastewater and Stormwater Management in Small Settlements, works in pilot areas across the Danube River Basin because every small community faces its own challenges: different landscapes, different risks and different local rules. In each pilot area, local communities, experts and decision-makers come together to design solutions that truly fit local needs. By testing ideas on the ground, the pilots show what works, what doesn't, and how sustainable, decentralised solutions can be scaled up to benefit many other communities across the region.

Key dates for the South Transdanubia pilot

• 7 May 2026: Study visit in Ormož.

• 26 November 2026: Training 1.

• February 2027: Training 2.

Pilot at a glance

• Location: South Transdanubia, southwestern Hungary (counties of Somogy, Baranya and Tolna)

• Settlements: Beleg, Kisharsány, Nagytótfalu, Oroszó, Ráksi

• Sewer network: none

• Stormwater facility: Oroszó has a stormwater drainage system (approx. 3,131 m)

• Wastewater treatment plant: none

The South Transdanubia pilot flyer is available in the D-CLEAN library in English and Hungarian.