At the Glina wastewater treatment plant, biogas and agricultural fertilizer are produced from sewage sludge. This is a very rare case, because most utility companies send tens of thousands of tons of sludge, which remains after the treatment process, directly to landfills. Which are already too few, too full or non-compliant.

An example of good practice for wastewater valorization offered by Apa Nova/Veolia for the "Second Life. Circular Economy Models" campaign.