Water Supply and Wastewater of the municipality of Delnice

Project completed
The water supply system in the area of Delnice is under reconstruction. © SECO

Delnice is located in the region of Gorski Kotar, where Switzerland and Croatia implement three water supply and wastewater projects. The uncontrolled discharge of untreated sanitary wastewater risks to pollute drinking water sources and catchment areas of the Danube and the Adriatic Sea. Moreover, the existing drinking water systems are in need of maintenance. A feasibility study, also financed through the Swiss contribution to Croatia, detects deficiencies and defines needs for action.

Country/region Topic Period Budget
Protecting the environment
Wastewater treatment
30.05.2017 - 31.12.2023
CHF  8’295’779

Note: the texts under all the headings, with the exception of 'Results achieved', describe the situation before the start of the project.


The benefitting municipality of Delnice is located in the region of Gorski Kotar in the north-west of Croatia between the Capital Zagreb and the coastal city Rijeka. Roughly 5,000 inhabitants are currently living in Delnice and its surroundings, which makes it Gorski Kotar’s main town. The region is sparsely populated and mountainous.

Although 86% of the households have access to the public water supply system and are provided with drinking water of good quality, the current infrastructure is in need of improvement. The main deficiencies are a lack of water supply continuity, an unreliable pressure in the water supply system and a risk of pollution because of worn-out and corrosive installations. These deficiencies are leading to an unsatisfying service quality. Today, the water loss rate of the region is estimated at 52%.

As per 2015, the sanitary wastewater of 44% of the households of Delnice and its surroundings was collected in a sewerage system and treated adequately in a treatment plant. Still, a vast amount of sanitary wastewater is either discharged uncontrolled into nature or has to be collected individually and treated at high cost elsewhere.

  • Contribution to the environmental protection of the groundwater and surface water in the Danube River basin
  • Sustainable economic development by ensuring better and more reliable water service quality in Delnice
Target groups

Inhabitants of the agglomeration of Delnice

  • Construction of a sewer system: 13,350 metres of pipeline and 10 pumping stations
  • Increase of the utilization of the existing wastewater treatment plant
  • Supply of equipment for the maintenance of the sewer system: 1 vehicle to clean sewerage and empty septic tanks, 1 vehicle for pipeline inspection including a robot camera, 1 device to detect leaks and illegal connections
  • Rehabilitation of water supply infrastructure: 23,000 metres of pipeline and 7 water tanks
  • Construction of new water supply infrastructure: 4, 400 metres of pipeline
  • Rehabilitation of 2,200 metres of channel for water transportation and energy production
  • Installation of a monitoring and control tool for drinking water (SCADA)

Achieved results:  

Results 2020:

1,200 metres of the main sewer have been assembled

17,000 metres of water supply pipelines haven been built or reconstructed

The rehabilitation of the water supply facilities is ongoing

Directorate/federal office responsible SECO
Credit area Swiss Contribution to the enlarged EU
Project partners Contract partner
  • The Ministry of Regional Development and EU Funds of the Republic of Croatia

Implementing partner
Croatian Waters – Hrvatske vode

Budget Current phase Swiss budget CHF    8’295’779 Swiss disbursement to date CHF    1’773’369
Project phases

Phase 10 30.05.2017 - 31.12.2023   (Completed)