Integrated urban water management (IUWM) in Buenos Aires is not unlike many large urban areas in Latin America where in past decades, more focus was placed on just a few sectors or perhaps only one sector. The water management philosophy in Buenos Aires has evolved to one that is integrating efforts in reducing water pollution, improving stormwater management, adding drainage infrastructure, and improving water supply and sanitation (WSS). Primary challenges in urban water management continue to be flood control and stormwater management as Buenos Aires is situated in the low-lying pampas region where heavy rain is expected all year long. Adding to the challenges, urbanization has outpaced planning and development in the various water sectors. Efforts have been made to control the major tributaries of Río de la Plata such as channelizing and building culverts into urban rivers, however, this has increased flooding as the natural meander and saturating ability of the rivers have been lost. Rapid urbanization and very large quantities of industrial discharge have also caused severe contamination of the water basins that Buenos Aires is built upon. The Matanza-Riachuelo river (MR), a tributary of the Río de la Plata (La Plata River), is a prime example and has become the most contaminated basin in Argentina.

In response to water pollution and flooding challenges, the Government of Argentina (GoA) is working with the World Bank to address industrial water pollution by providing technical assistance and mentoring to the 50 worst industrial polluters which represent 95% of the total effluent. Oversight and monitoring is provided by the Matanza-Riachuelo River Basin Authority (ACUMAR). The Urban Flood Prevention and Drainage Program (APL) is the government's commitment to flood prevention and risk management and falls within the framework of the Buenos Aires Hydraulic Master Plan. The "Master Plan" focuses on implementing non-structural measures throughout the entire city.

Recent history in Buenos Aires urban water management is notable for its move to privatization of the water and sanitation systems. Signed in 1992, the Buenos Aires water concession was a unique example of water privatization on a large urban scale for its rapid implementation. The concession handed control of water and sanitation systems to the French company Suez S.A. Generating controversy for its size, the privatization was successful in that improvements were made to water and service coverage while efficiencies were gained within the water company itself. Additionally, a near 27% reduction in water tariffs quickly followed after the signing of the concession. After a renegotiation of terms in 1997 that generated wide criticism, the concession was canceled in 2006. Water and sewer provisions in the Buenos Aires Metro Area (BAMA) have since been handled by a conglomerate of companies called Water of Greater Buenos Aires (Aguas del Gran Buenos Aires).

Economic and social conditions Argentina enjoyed four years of rapid recovery from the economic and social crisis of 2001-02, which was one of the most severe losses of income and downturns in living standards on record. Effective macroeconomic management, focused on the generation of primary fiscal surpluses, has helped to sustain this strong performance. Consequently, average real GDP increased by nearly 9% per year between 2003 and 2006, surpassing the maximum GDP reached in 1998. Poverty and unemployment have fallen substantially from their peaks during the economic crisis. Poverty has declined to about 31% from a high of over 57% in 2002, while unemployment fell to near 11% from 21% in 2003.

The period in Argentina between 1990 and 1993 was a time of transition away from social policies, government support devices, and welfare systems to an IMF-backed structural adjustment in economic and market policies. During this time, crime became a serious problem with the creation of an informal criminal economy that sought to take advantage of a lack of economic authority. Crime rates rose 286% between 1992 and 1995 and in 1995 the former President, Carlos Menem was re-elected with international praise for achieving low inflation, privatizing state-run companies and the currency peg to the dollar. Crime has continued to grow as a considerable social concern in the aftermath of the 2001 recession and a reversal of the currency peg where hyperinflation ensued. Consequently, the arms and drug trade has flourished and slums in Buenos Aires grew by 114% during the 1990s to around 113,000 people. These slums lack basic public services and law enforcement, and have become safe havens for criminal activities.

The Matanza-Riachuelo river (MR) basin is home to Argentina's largest concentrations of urban poor. Of the approximately 3.5 million inhabitants in the basin, 1.2 million live below the poverty line. An estimated 10 percent of the total population in the MR Basin lives in informal settlements, often in flood-prone areas and/or near open garbage dumps. The poorest populations living alongside the river are in constant contact with numerous contaminants ranging from untreated organic waste to toxic industrial chemicals.

Geography and climate Buenos Aires lies in the pampa region of Argentina and is bordered on the eastern and north-east sides by the Río de la Plata, on the south and southeast side by the Riachuelo and to the northwest, west and Southwest by the Avenida General Paz, which is a long highway that separates the Buenos Aires Province from the city.

The region was formerly transected by small tributaries and some lagoons, some of which were refilled and others piped. Among the most important small tributary basins are the Maldonado, Vega, Medrano, Cildañez and White. In 1908 many of these tributaries were channelized as floods damaged the city's infrastructure. Beginning in 1919, most creeks were enclosed. Notably, the Maldonado was re-engineered in 1954 to flow underground in tubes and currently runs underneath Juan B. Justo Avenue.

The city has a humid subtropical climate and the average annual temperature is . The city gets of rainfall per year. Rain can be expected at any time of year with March being the wettest month (5.3 inches) and June the driest month (2.5 inches).

The Buenos Aires water concession of 1992

The signing of the Buenos Aires water and sanitation concession in 1992 attracted worldwide attention and was the source of considerable controversy for its scale of private participation in the Argentine water and sanitation sector. In addition to being one of the world's largest water concessions, the Buenos Aires concession has remained interesting for a number of other reasons. First, the rapid implementation of the Buenos Aires concession contrasted with the slow movement towards private participation in other large urban water systems, such as Santiago or Lima. Second, the reform was widely acclaimed for generating major improvements in the water and sanitation sectors, including wider coverage, better service, more efficient operation of the company, and a reduction in waste. What makes these improvements especially striking is the immediate 26.9 percent reduction in water tariffs that followed the signing. Finally, the Buenos Aires case is of interest because the contract was renegotiated in 1997, provoking criticisms of the original bid and the regulation. More recently, the concession was revoked in 2006 and remained under arbitration in 2008.

Infrastructure

Water supply Over most of its history, Buenos Aires has remained a city with a quality water supply delivered by the immense Río de la Plata and surrounding high plains that have abundant high quality groundwater below them. In the outskirts of the city, the inhabitants have good access to wells and piped water.

Surface Water: The La Plata sub-basin's catchment area is 130,200 km2 and constitutes (4.2%) of the world's fifth largest river basin – the La Plata, extending over 3.1 million km2, five countries (Argentina, Bolivia, Brazil, Paraguay, and Uruguay), almost 50 major cities, and supporting over 100 million inhabitants. The mouth of the La Plata River is 230 km wide and separates Argentina from Uruguay. The three main watercourses that form the base structure for the region's drainage network are the Luján, Reconquista, and Matanza-Riachuelo Rivers. The Luján River, 128 km, has the largest catchment area of nearly 3,300 km2 and runs from southeast-northeast before discharging into the La Plata River. The Reconquista River is 82 km long, drains a catchment of 1,738 km2 (the lower 40% includes urban and semi-urban populations), and discharges into the Luján River. The Matanza-Riachuelo River (known as Riachuelo from its lower catchment) is 510 km long and eventually discharges into the La Plata River.

Groundwater: Over many decades a significant proportion of the water-supply of the Buenos Aires Metro Area (BAMA) was obtained from three major groundwater reservoirs found at different depths, quantities and qualities. The Pampeano, Puelches, and the Parana account for these three reservoirs of groundwater and reached their pinnacle of use in the late 1980s. At that time BAMA underwent a switch from groundwater to imported surface water which has led to groundwater levels to rise to the point of frequent flooding because of the close proximity of the water level to the surface.

Drinking water Aguas y Saneamientos Argentinos is the primary water service provider in the metropolitan area serving the city of Buenos Aires and 17 municipalities, while Aguas Bonaerenses serves the remaining municipalities. Almost 95% of the water supply comes from the La Plata River (4,442,065 m3/day), while the rest is extracted from the ground (231,416 m3/day) and is treated at one of three plants. AySA is building two additional water treatment plants that will increase daily capacity by 947,040 m3.

Stormwater and drainage Due to rapid urbanization, topographic elements, and the occurrence of severe storm events in Buenos Aires, flooding has become one of the most serious problems affecting the normal life of Buenos Aires citizens. Extensive and frequent damage to urban, commercial, and industrial infrastructure is also prevalent. The continuous increase in the degree of impermeable surfaces (only 10% of the city is open and green space) in the city has altered normal functioning of the stormwater drainage network. Today, the system cannot adequately convey the stormwater runoff generated after a storm.

Each of the three most important catchments (Maldonado, Medrano and Vega) are drained by a large drainage pipe that follows in the direction of the former watercourses. Typical dimensions range from 15 m to 20 m wide and 3 m to 4 m high with an internal supporting structure of columns and beams that results in interference of stormwater flow and can cause back up and increased flooding. The city counts approximately 1400 km (870 mi.) of stormwater conveyance covering an area of 30,000 ha (74,000 acres) with 7,000 sub-catchments structures, 12,000 street-level storm drains, and 6,000 sewer drains.

Wastewater treatment AySA has four wastewater treatment plants (WWTP) that currently treat only 5.3% of wastewater before discharging it into the La Plata River. To improve this situation, AySA is in the midst of constructing another wastewater treatment plant Del Bicentenario, which will increase the City's treatment capacity by 120,000 m3 per hour (current output is 2,249,494 m3/day).

Water challenges

Pollution