The project solutions envisaged the construction of new modern wastewater treatment facilities, which meet the environmental requirements for wastewater treatment, in the territory where old operating wastewater treatment facilities of Viekšniai town were located. New wastewater treatment facilities, i.e., technological building and tank of biological wastewater treatment facility, were installed on the existing sludge sites. Wastewater treatment includes the following stages: pre-treatment, biological treatment, sludge treatment (compaction in a sludge tank).

Wastewater treatment facilities in Veikšniai town (in the direction of wastewater flow) consists of the following links and elements: tank receiving incoming sewage (septic sludge), sewage pumping station, technological building (sewage distribution chamber, mechanical gratings with integrated bar screen, bypass line with manual gratings), biological treatment facility (covered), two technological lines (anaerobic tank, denitrification tank, nitrification tank, secondary precipitator, compaction tank for excess sludge, sampling well, effluent flow meter, treated effluent discharge line and outlet to the receiver).