Provisión y disposición de agua en 243 ciudades argentinas: Servicios ecosistémicos en el continuo territorio-ecosistema acuático-centro urbano

Cities depend on different ecosystems that provide them with services. In the case of water supply and effluent disposal in Argentine cities, its recognition is still incomplete and fragmented. Here is presented a first database that maps and classifies the water supply sources and effluent destinations of all Argentine cities >20000 inhabitants (in 2010). Utilizing existing reports, journalistic news and satellite information, water intake and discharge points were recorded, along with other associated infrastructure in 243 cities. It was found that 30.5, 17.5 and 12.6% of the population is exclusively supplied by large transboundary rivers, groundwater and internal rivers and streams, respectively, with 25.2% supplied by mixed sources. The cities that are connected to the public sanitation networks resort mainly to internal rivers and streams (26.6%) for their disposal; however, of the urban population that is not connected to the sewage network, a high proportion discharges into free aquifers. Most Argentine cities do not return sewage water to the same system that supplies it, predominantly transfers from underground sources to internal rivers and streams. The database evidences the contrasting ‘effluent pressure’ (population/flow rate of the receiving system) between cities linked to large rivers (e.g., Paraná basin, 273 inhabitants.m-3.s-1) and internal basins (e.g., Mar Chiquita, 16141 inhabitants.m-3.s-1). This database, open for consultation and updating, makes visible the spatial and hydrological connection between cities and the hydrographic network, helping to improve water security and prioritize efforts to protect aquatic ecosystems that guarantee it from all levels of management.