The collaborative process that led to the design and launch of the Pilcomayo River Early Alert and Monitoring System
The first sign of catastrophe occurred in Tupiza on January 19, 2018. Intense rain caused the water to rise and spill over the riverbanks, devastating the neighborhoods known as 21 de Diciembre and Quechisla. For several weeks, the water stood without receding. All of southern Bolivia was on high alert due to torrential rains and the threat of flooding from 18 rivers in the country, according to reports from the Servicio Nacional de Meteorología e Hidrología, SeNaMHi (the National Weather and Hydrology Service). On January 21st, local digital media reported that Tupiza had been flooded, at which point the participatory Pilcomayo Early Alert System was set into motion. At 10.30 a.m. that day, the Puente Aruma measurement station detected the passage of the body of water. The first alert was issued: the Pilcomayo will continue to rise. This first alert of the year was repeated throughout the system by way of the WhatsApp group and other social networks. In this manner, people in the lowlands of the Chaco plains knew of the coming disaster and were able to save themselves.

Overflow of the river in Tupiza. The water swept away over 50 dwellings and threatened another thirty. Photo: ABI
The Pilcomayo is not just any river
The Pilcomayo River begins in the Bolivian highlands of the Andes mountain range. From its source, the river descends to the Chaco plains and finally branches off into several smaller rivers that flow into the Paraguay River. The Pilcomayo has an atypical characteristic. It is one of the rivers that moves the most sediment in the world. Each year, the Pilcomayo moves approximately 100 million tons of sediment, which amounts to one-third of the river’s volume. At some point, all this material settles on the riverbed, and this is when the river overflows and creates marshland. Northern Argentina’s Formosa province is known for its marshlands with some semi-permanently flooded areas in the form or lagoons or estuaries. The Pilcomayo’s unique qualities also make it unpredictable. The river grows, recedes, and changes course. It may flow into Argentina, or toward Paraguay, or reach both countries. In just a few decades, the river has receded nearly 100 kilometers due to a buildup of the sediment that the river carries throughout its length of its 2,500 kilometers. This behavior, known in hydrology as auto-siltation, is present in only eighty rivers in the world.
Panorama of the Pilcomayo
Old oil well in the middle of the water of the Potrillo-La Tigra Norte channel in Formosa province, Argentina. This image demonstrates change in the river’s flow over time.
The Pilcomayo River impacts southern Bolivia, Paraguay, and northern Argentina. The lives of thousands of people depend on this river, not only because it is a means of subsistence, but also because it represents risk during the rainy season. Due to this risk, the need arose for an alert system to forewarn river populations of this indomitable river’s fluctuations.
The joining of technology with citizen participation
The Pilcomayo River Alert System is supported by the Gran Chaco Proadapt initiative. The system is built on the knowledge gathered over nearly two decades from people and organizations of the river region. Gran Chaco Proadapt an initiative created by members of Redes Chaco. The initiative brings together various actors in the three countries that share the Pilcomayo river basin and work to adapt productive systems to climate change in the region. The effects of climate change on the Gran Chaco include, among other things, extreme weather events of increasing frequency and intensity. The unusually intense rainfall that caused flooding in January and February of 2018 is one example. The rains in Tupiza, although quite localized, influenced the rising waters of other rivers. Deforestation and loss of native forests are also exacerbating factors. Land without vegetation is unprotected and water can flow greater distances with stoppage. This phenomenon occurred in some Argentine and Paraguayan forests that were flooded for the first time when floodwaters reached areas they had never before touched, after traveling great lengths of deforested land that provided no resistance.
The unique nature of the Pilcomayo and its broad river basin required an equally unique alert system, one that would take into account the characteristics of the territory and its people. Such is the Pilcomayo Early Alert System: it is designed to fit the territory along with its environmental and social characteristics. The two main pillars of the system are technology and the direct participation of the population.
The history of a collaborative process
Thirty years ago, the Pilcomayo river was little known. It was not among the region’s geopolitical priorities. But in 1983 an unusual event occurred: a devastating flood in the summer of that year became the first of many that would occur until 1989. This series of floods dramatically transformed the geography of western Formosa in Argentina and the south-west of Boquerón in Paraguay. Although the transformation became evident over those years (1983-1989), change had been gestating, quietly and continuously, since 1972.
“The river is a person. It tells us things we must listen to.” So say the indigenous inhabitants of the river basin. The 1983 event was a call to attention to changes that already had been taking place. With the new millennium, many inhabitants, especially the Wichi y Qomlaje’pi of western Formosa, began speaking of these changes. Neither the public sector nor academia had taken notice, but the changes affected these people’s lives and means of production. In common knowledge, daily conversations, and day-to-day life, the demand for attention and solutions was always present. This inspired a group of local people to systematically record variables that define the river’s behavior. These records and systematizations would become the basis of hydraulic interventions undertaken in subsequent years to contain the floods and protect communities.

The Weenhayeck community in Bolivia.

Indigenous communities. Women crossing the bridge to Pozo Hondo.
In 2004, the people’s records system began to catch the attention of institutions that could collaborate in the implementation of larger-scale actions. The incorporation of local knowledge had already demonstrated positive results. One example of this was the plan for the Farías Canal in 1996. The Farías Canal is named in honor of Gomez Farías, a famous Wichí of Boquerón. His deep knowledge of the river’s behavior was critical to developing the plan for the canal that would return water to the pueblos in Formosa. Access to this water was lost when the river receded. Gómez Farías and other knowledgeable locals showed the engineers where they should dig the canal. The Farías Canal remains in operation today.
In 2005, Formosa’s provincial government formally recognized the value of local knowledge in the design of the public works to be developed. At that time, residents influenced the path of canals in the La Estrella wetlands located in the north-west of the Ramón Lista department. Year after year, this same local population identified new critical areas in the wetlands and at-risk areas in the event of extreme weather. The participatory methodology was enriched in this manner, as its main support came from and continues to be in the interest of local inhabitants.
People’s concerns gave rise to the process and, from there, an appropriate model developed in which the people took ownership. Local knowledge; tours of the area by technical experts, specialists, and residents from other regions; conversations about historic events that had been recorded in collective memory; challenges faced by population caused by the problems of rising and falling waters; meetings and gatherings–all of these factors contributed to gathering the content and information necessary to know the river and understand its great capacity for change. In addition, indigenous people had ancient stories about these transformations. These stories surprised the non-indigenous residents who had never before imagined that the river could have been so different from the one they knew.
Image 6: The Churcal community west of the Formosa province, Argentina.

Image: Sediment accumulation due to the floods. Caso Misión Anglicana de San Andrés, Formosa province, Argentina
The consolidation of a model based on community organization
Over time, various non-governmental organizations working in the basin and governmental agencies of Argentina, Bolivia, and Paraguay joined in the process. In this manner, the participatory model built on knowledge of the river was consolidated. This made it possible to implement more effective actions in the event of an emergency.
By 2016, preliminary risk maps had been developed. The risk maps were informed by all those years of knowledge-sharing with people from different areas. In these maps, there was a convergence of information from: area-specific local knowledge; the building of local knowledge of the basin; and scientific knowledge related to weather analysis of satellite images since 1976 and, in some cases, since 1972. In addition, rainfall data used to identify the years of greatest rainfall was the main resource used to determine the areas at-risk of excessive precipitation. The field data collected was also confirmed by the people in the region.
The question has been asked many times: How was participation of the local population achieved? The answer is: it was not achieved. It was already there. Local participation arose from concerns caused by catastrophes that had taken place since 1983. And, collectively, the population developed a methodology adapted to the forms of participation of each culture. At that time, the population did not see the importance of the system in development, so it did not make progress. In the summer of 2018, however, severe flooding changed the perspectives of many about the system.

The local population reinforces its defenses. Santa Este, Salta Province, Argentina
The science and technology behind the system
In addition to local knowledge, the system is informed by hydro-meteorological data from official sources. It includes hydrological and climatological monitoring of the river by SeNaMHi in Bolivia, Argentina’s National Weather Service, Paraguay’s Directorate of Meteorology and Hydrology, and the Executive Directorate of the Trinational Commission of the Pilcomayo. River monitoring is performed mainly by SeNaMHi in conjunction with the Deputy Secretary for Water Resources of Argentina and within the framework of the Trinational Commission of the Pilcomayo. All this information is complemented by the use of remote sensors and satellite images that, collectively, make it possible to read the territory and the river’s movements.
Although hydrological and climatological measurements of the Pilcomayo River continue to improve, they are still considered to be insufficient. This is due to several factors, ranging from technical difficulties with installation and maintenance of monitoring equipment to disagreements in negotiations among the various governmental sectors involved in basin management. In addition, insufficient resources are allocated by the three nations that share this territory. In this context, how do we find our way through the difficulties and achieve our common objective to safeguard communities from possible flooding? The answer lies in two elements: technology and community organization.
Technology has been vitally important to optimizing the communications system for transmission of timely alerts, as well as to receiving information from residents in order to adjust information generated by remote sensors. Access to mobile phones, the Internet, and widespread use of messaging applications and social networks have extended the network to reach more people and cover greater distances in less time.
But there is still much work to be done in the region in terms of communications. There are still extensive areas without mobile phone coverage and very limited Internet access. In Argentina, a public-private partnership has expanded training and connectivity centers to increase the population’s digital literacy and support access to technologies and the Internet. Many of these centers, called Gran Chaco Nanum, were key to the operation of the Pilcomayo Alert System during the floods. In Paraguay, the expansion of agricultural businesses has motivated private businesses to provide Internet services through WIFI technology. However, much remains to be done throughout the basin. Governments, telephone companies, and Internet service providers must work together to guarantee access to information and communication technologies. In the case of at-risk zones, where human lives and production systems are at stake, access to information and communication technologies is a need that, in these times, is at the level of an inalienable human right.
Installation of the measurement station in Campo Largo.
Instruments for the Campo Largo Station Photo: Gran Chaco Proadapt
The Day of the Disaster
The catastrophic flooding of January 21, 2018, in Tupiza gave the Early Alert team reason to believe this was not just any flood. The flooding had just begun. Four days before the water reached the Santa Victoria del Este municipality in Salta, the first alert was issued, and communities in the lower river basin began taking measures for evacuation and erecting flood barriers.
The Salta province felt the greatest impact. The water first arrived in Salta and then spread throughout another 200 kilometers over nearly two weeks. Towns like Santa María, Misión La Paz and Santa Victoria de la Paz were evacuated or were put in a state of alert upon shoring up their defenses. Thanks to the Alert System, 5,500 people were successfully evacuated from Salta alone. Another 2,500 people self-evacuated in Formosa from the La Estrella wetland area. The time-lapse between dissemination of the alert and the water’s arrival allowed the people time to accomplish the second objective of the Alert System: to save their means of production. This action was indispensable to the people so they could return to a solid foundation after the flood.
The basis of the alert system
Hydro-meteorological data and remote sensors are not considered sufficient cause to issue an alert. Rather, a person must sound the alert when they have noticed some abnormality. People who have grown up in the mountains and alongside the river are aware of everything that happens because they know how to interpret bird song, vibrations in the air, and movements of the water. They know their natural surroundings. Such knowledge allows a person to observe the sky and anticipate rain. A fisherman may see the river and anticipate rising waters. The Alert System incorporates not only measurements of the river and climate, but also the knowledge of people who know the river through their own experiences. This knowledge is the fundamental pillar of the alert system. Without it, the system could not work.
Social organization is the other fundamental element of the alert system. The tool developed by members of the WhatsApp group is much more than a communication tool. The tool transformed 800 individuals in various groups into one community in solidarity. A common discourse and shared vision of the basin were developed that, thus far, had not been part of the region’s social dimension. The groups involved in monitoring and issuing alerts during the 2018 flood became communication channels of great importance to residents affected by the rising water and to emergency service organizations. In a very practical sense, telecommunication was the organizational backbone that brought various regional actors together under the umbrella of a social and hydrological concept of the river basin. The actors were united among themselves and with the rest of the affected residents.
Image: Defense measures against floods
From crisis to opportunity
Technology plays an increasingly important role in society. Technological progress has made the development of the Pilcomayo Alert System possible. This system is vital to the survival of many Argentine, Bolivian, and Paraguayan communities in the river basin. Conversely, technology also has distanced people from nature and, therefore, contributed to the loss of the local knowledge needed to be able to issue an alert.
Forty years after the great flood of 1983, the reality of Gran Chaco children is very different from the reality lived by their parents. Favored toys today are cell phones, tablets, and digital devices. Little by little, children’s contact with nature is diminishing, and essential knowledge– not taught in schools, but learned through experience and contact with the land– is becoming lost.
The organized community, however, is no stranger to this new reality. And, for this reason, they knew how to take the critical situation caused by the flood in January and turn it into an opportunity. When the water receded, the first action taken was to assess the affected areas in order to quantify losses. In the western Formosa region affected by the flooding, people from the Qomlaje’pi groups formed what could be considered an intergenerational team. Elders knew the land and could see changes in the terrain. They joined with their youth, who worked with technological devices and could record the losses, graphically chart the landscape, and subsequently process the information with other technological tools.
The outcome was a complete success. The survey went far beyond its original proposal. It also brought together two generations that shared the same land and the same need. This need to adapt to changes in the river required two elements: knowledge of technology and knowledge of the land. Youth possess technological knowledge and the elderly have profound knowledge of the land. People of both generations toured the affected areas together, and this revived the young people’s interest in learning more about the environment.
Collaboration for action
The Pilcomayo is a river full of surprises. The river can change, and, in fact, it does in a matter of a few years and even from one year to the next. In the face of the river’s transformations, engineering can do little more than delay the natural process. Added to the river’s variable nature is the phenomenon of climate change, introducing a factor of uncertainty that increases the risks. Communities inhabiting the river basin understand the need to adapt to the reality of change that affects all things. That is why people must be prepared not only to protect themselves from changes, but also to adapt their lives to new conditions in order to ensure their survival.
The early alert system is one of many adaptation measures needed to sustain the thousands of people living within the sphere of influence of the Pilcomayo River. In the end, the effectiveness of adaptation measures will depend on the relationship between people and nature. This relationship has become distant, in part due to the arrival of technology, and must be recuperated by the next generations. The greatest challenge, therefore, is cultural. As does the river, everything changes, including relationships. The relationship of mankind with nature is no exception. Perhaps this is the greatest challenge faced by not only the Gran Chaco, but also by humanity itself.
It bears mention that crisis situations also offer opportunities. The crisis generated by the Pilcomayo floods became an opportunity to strengthen the alert system and ensure its continuity for and by new generations. This is the achievement of Gran Chaco communities that are organized and aware of their own reality.
The Pilcomayo River Alert System is an example of all that can be achieved by organization and social participation. It is an example that may be followed by other communities throughout the world that need to rebuild community ties in order to respond to their needs. However, the emergence of a crisis alone is not an opportunity in and of itself. People have the capacity to create opportunities. The hillside, the river, the birds, are always there, revealing their secrets in each song and with every rainfall. People must know how to listen and understand them.
Detailed description of the Pilcomayo Participatory Monitoring and Early Alert System
By: Yanina Paula Nemirovsky, Fundación Avina