27: Freshwater quality, 2016 (https://www.eea.europa.eu/soer-2015/europe/freshwater#tab-based-on-indicators) Many years of investment in the sewage system, and better wastewater treatment under the Urban Waste Water Treatment Directive — together with national legislation — have led to some remarkable improvements. Europe's waters are much cleaner today than they were 25 years ago when large quantities of untreated or partially treated urban and industrial wastewater were discharged into water. Around half of Europe’s rivers and lakes are still polluted, a major environmental review has found, despite a 15-year-old target to restore all the continent’s waters to good ecological health by 2015. Among the worst offenders are Germany and the Netherlands, where more than 90% of fresh water has failed to reach good ecological status (see chart, below). Waters with good status are defined as those that deviate only slightly from “undisturbed” reference conditions, which are based on measurements of chemical pollutants such as nitrates, biological indicators including the abundance of caddisflies and other invertebrates around rivers, and the physical condition of the water (whether a river is in a free-flowing, near-natural course, for example, or has been affected by structures such as hydroelectric power plants). Pollution from agriculture and urbanization is mostly to blame. “Europe has not been very good at getting rid of manure from animal farming, nor lowering fertilizer use,” says Bruyninckx. Urbanization leads to changes in land use, as farmland pastures and forests are converted into mining and construction sites.