Please ensure Javascript is enabled for purposes of website accessibility Rijeka WWTP – Europski projekt aglomeracija Rijeka

Wastewater treatment plant

Wastewater treatment plant

A wastewater treatment plant will be built at the Delta location by using BAF technology, with a capacity of 200,000 PE (population equivalent) and a maximum storm inflow of 1,000 litres per second. It will use secondary treatment in accordance with the size of the agglomeration and the sensitivity of the sea in this part of the Gulf of Rijeka.

It will be based on biological wastewater treatment procedures, with a station for receiving the content of septic tanks, production of biogas from sewage sludge for own energy needs and thermal drying of sludge. The wastewater will be biologically treated before being discharged into the sea, and the sludge will be treated and dried to a content of at least 90 percent of dry matter.

All parts of the plant will be in closed facilities, and will be built at Delta, near the existing WWTP, on the right bank of the Rječina river. The works will be performed according to the FIDIC Yellow Book, which the contractor will follow when preparing the design and performing the works. All the works will be carried out on a building plot of 2.2 ha with maximum dimensions of 224 × 30 m. The project foresees the construction of technological buildings within the block matrix, the WWTP administrative building and roads and green areas of a public nature.

The wastewater treatment plant must meet secondary treatment in accordance with the capacity of the agglomeration and the recipient into which the wastewater is discharged. The recipient of wastewater from the Rijeka agglomeration is the sea of the Gulf of Rijeka, which according to the Decision on the designation of sensitive areas (OG 81/10) is a less sensitive area for wastewater discharge.

The construction of the wastewater treatment plant will contribute to the protection of the coastal sea and the local waters of Rijeka, the preservation of marine habitats and species, and the reduction of pollution and protection of human health.

The value of the contracted works is 69,360,939.73 EUR (excluding VAT).

The contractor is a group of tenderers comprising


The construction supervision service is provided by a group of providers:

  • INSTITUT IGH d.d., EPTISA ADRIA d.o.o. and PROJEKT d.d. Nova Gorica.
    The deadline for the completion of works is 50 months.

The works covered by the contract include the following:

  1. Design
  2. Construction of a wastewater treatment plant
  3. Construction of a connecting pipeline to the existing offshore outfall
  4. Construction of a bridge over the Rječina river
  5. Construction of an administrative building of the company KD VODOVOD I KANALIZACIJA
  6. Trial operation of the wastewater treatment plant
  7. Demolition of the existing wastewater treatment plant

Contracting Entity

Komunalno društvo VODOVOD I KANALIZACIJA d.o.o. za vodoopskrbu i odvodnju Rijeka (Utility company WATER SUPPLY AND SEWAGE Rijeka)
Dolac 14, 51 000 Rijeka, Croatia
TIN (OIB): 80805858278
Phone: 00385 51 353 222