To develop technical and economic substantiation for LLC ‘Rīgas ūdens’ waste water treatment plant (WWTP) ‘Daugavgrīva’ sewage sludge treatment and utilization infrastructure improvement measures in accordance with the development guidelines and planning period until 2040.

Subject of the procurement: this study should include, international experience of sludge treatment and utilization, review of the best international practices identified and evaluated for their potential relevance to the Riga city ‘Daugavgriva’ WWTP (PE 700000 to 1M) to develop a methodology for selecting appropriate sludge management, treatment and utilization options on the basis of a lifecycle assessment approach. Sludge management study for Riga City should include short and long term strategies for sludge amount up to 11000 tDM/a.

Two features of the feasibility study must be given detailed attention:

First, the social acceptability of sludge reuse in agriculture and land application, composting, needs to review, to be built up technical and economic reliable aspects.

The second-comprehensive review not only at sludge utilization applications and required treatment technologies but also the surrounding planning, institutional, regulatory, and economic frameworks that allow these technologies to be implemented.