The abuse of the Maipo River watershed that no longer reaches the sea

E-mail Print

 Maipo River, Chile. Photo: Ricardo MirandaMaipo River, Chile. Photo: Ricardo Miranda

By Juan Pablo Orrego
Orrego is president of the Santiago, Chile-based environmental group Ecosistemas.
As I finish writing this column, the Maipo River is for the first time disconnected from the sea, with its mouth clogged with sand that the last tidal wave pushed into the estuary, finding no resistance, since the great river brings practically no water. Days before the historic phenomenon, the Maipo flowed between Santo Domingo and Llolleo with barely 1 m3/s. All of them clear symptoms of the final collapse of the river ecosystem. At the same time, Aguas Andinas repeatedly warns that the supply of drinking water to Santiago is in danger, due to the high turbidity of the Maipo caused by recent alluvium in the upper reaches of the Volcán river valley. In the Yerba Loca Sanctuary, in the Mapocho river valley, a large landslide left more than 20 people isolated, all this in the middle of summer. All this in the middle of summer. What is happening? Perhaps, with the following information, this question can be answered in part. 
The global dynamic, where "developing" countries deliver natural goods, raw materials, to "developed" countries, is replicated at the national level where rural areas - ecosystems, human population, biodiversity - are impacted by the installation of industrial activities or by resource extraction for the benefit of urban areas. The Maipo River basin is a crude example of this dynamic, and illustrates what is happening in general throughout Chile and many "third" world countries.
From the founding of Santiago to the present day, domestic and foreign individuals and companies have negatively impacted even the farthest reaches of the watershed, primarily to serve urban areas in multiple ways. The projections of demographic and real estate growth, as well as the expansive plans of the extractive sectors, allow us to deduce that the ominous socio-ecological panorama observed today in the Maipo River basin - as in many others in the country - will worsen in the coming years.
Throughout the watershed, multiple critical symptoms of degradation, industrial saturation and overuse can be observed, caused by uncontrolled urbanization and its gaseous emissions, liquid effluents, and waste of all kinds. The latter accumulate in 5 mega-landfills, 79 illegal mega-dumps, and 600 micro-dumps. The effluents include the 'very sewage' water from toilets, sinks, dishwashers and washing machines, septic tanks and cesspools of 8 million Chilean men and women, processed in 13 treatment plants, with high levels of direct or semi-treated discharges into rivers, estuaries, lakes and wetlands.
It is increasingly difficult for the watershed, which is severely deforested in its three sections and over-urbanized, to respond to the very high and growing demand for urban, rural and human drinking water in general, which includes sub-servient agriculture and livestock farming, agricultural activities that together generate by far the largest water demands in our country, concentrating 83% of consumptive water rights.
According to data from (CR)2 (La crítica situación del agua potable en la R.M., 24/06/2022) the consumption of drinking water in Greater Santiago (GS) is approximately 584,000,000,000,000 liters per year -considering an average consumption of 200 lt per day per person, although in the 'high' communes the consumption can reach 400 lt. If we add the irrigation of green areas, and the consumption of industry and commerce, the astounding amount that the R.M. sucks in per year reaches 851,472,000,000,000 liters. Eighty percent comes from the Maipo River, and the remaining 20% from the Mapocho River and the El Arrayán estuary.
The Maipo River near Santiago no longer arrives to the sea. Photo: OjosdemarThe Maipo River near Santiago no longer arrives to the sea. Photo: Ojosdemar
The GS alone covers with a cement slab 90,000 ha of what was once - 4 centuries ago - some of the best agricultural land in the world, of a quality found in only 11% of the earth's crust. In addition to the urbanized area of the GS, there are numerous "satellite" conurbations that are seen as growing gray patches in the basin, many of which are close to joining and becoming part of the huge conurbation of the GS.
Large-scale mining operations weigh heavily in the basin -235,000 tons of copper, 92% of gypsum production and 25% of the country's limestone-, and related works -28 tailings dams; 11 active, 17 abandoned-; also the infrastructure for electricity generation and transportation: 18 hydroelectric plants, 3 large thermoelectric plants, and innumerable transmission lines that transect the region in all directions, as well as the gas and oil pipeline networks that total 1,195 km in length.
The Maipo River suffers massive water withdrawals for drinking water, which must be "treated" in two Aguas Andinas mega-plants, and minor withdrawals from 22 other concessionaires, as well as massive withdrawals for agro-industries - monoculture plantations such as avocado, walnut and export vineyards - and for vegetable production. The total area of irrigated agricultural land amounts to nearly 140,000 ha. In the town of La Obra, at the entrance to the Maipo gorge, only the historic San Carlos Canal captures practically all the waters of the Maipo with large gates, and carries them northward for 31.5 km parallel to Tobalaba Avenue, and finally delivers them to the exhausted Mapocho River to irrigate crops to the south and north of its own tributary, which returns the rest of its own waters to the Maipo, at the height of El Monte.
For their part, the riparian ecosystems - wetland systems of rich biodiversity, fundamental for the health of the river, which are deployed on its banks, dependent on the natural variations of the flows and floods - suffer the uncontrolled extraction of aggregates from the beds of the Maipo, tributaries and estuaries, to make concrete and supply the also uncontrolled construction of buildings in the GS - real estate boom, which begins to capitulate with numerous bankruptcies of companies.
The growing water demand of the agricultural, urban, hydroelectric and mining sectors, together with climate change, clearly indicate that the socioeconomic pressure for water, scarcity and the consequent social conflict will increase. The institutional framework does not show full awareness of this situation, nor a real commitment to national water security and the state of the deteriorated ecosystems that still attempt to sustain it; integrity that in turn depends entirely on the availability of water. Without water, ecosystems collapse, wither and desertify.

"The growing water demand of the agricultural, urban, hydroelectric and mining sectors, together with climate change, clearly indicate that the socioeconomic pressure for water, scarcity and the consequent social conflict will increase. The institutional framework does not show full awareness of this situation."

Maipo River. Photo: OjosdemarMaipo River. Photo: Ojosdemar
A large part of the population of our country, deprived of integral quality education, due to the negligence of the State, and, therefore, of an environmental culture for synergic ecological action, trashes and damages almost everything in its path ...without realizing that what it is mistreating is its own homeland, its home, its own extended body, its quality of life.
The water crisis, the degradation of water courses, bodies and sources, has a plethora of causes, but among them gravitates in particular the non-consideration of the watershed as a geographical, ecosystemic and socio-environmental frame of reference. Without this, and its systemic perspective in space and time, the management of the territory does not really exist, and this is assaulted, vandalized, in a chaotic way, with very few considerations of substance and safeguards.
With respect to large-scale river interventions, considerations are largely reduced to determining arbitrary and discretionary ecological or minimum flows, ignoring, precisely, the integrity of the basin, with a simplistic and reductionist linear approach, juggling with complex mathematical formulas around monthly and annual flow averages. Rivers are complex stochastic ecosystems, fluctuating, seasonal, variable from year to year, alive and free, a reality that these formulas ignore and cannot encompass.
It is practically impossible for a minimum flow established according to current laws and regulations to preserve the ecological health of a river, and therefore of the watershed, since the integrity of the river ecosystem depends on the integrity of the watershed, and vice versa. This is common sense, but our country's legislation does not incorporate this holistic view. The disastrous consequences of state industrial and private corporate practices throughout our country demonstrate that the "methods" and analytical frameworks used to evaluate and authorize projects are highly deficient and deeply flawed; the opposite of systemic, multidimensional and transdisciplinary. The result is the gradual collapse of ecosystems that is engulfing us like an entropic ecological tsunami.
The cumulative impacts of several centuries of anthropic interventions in the basin, decided and carried out without socioecological wisdom or long-term vision, have degraded it, impoverishing its structure, organization, complexity and biodiversity, to the point that we have lost the notion and memory of how the basin and the river, glaciers, lakes, lagoons and wetlands, flora, fauna and fungus used to be. How do we project the regeneration of an "original" ecosystem so different from the current one, and so much richer ecologically, that it is hard to believe it ever existed? Most of the inhabitants of the MR do not know this environmental history, they do not know about the beautiful bioregion that flourished here, between the mountains and the sea, full of life - including human life - in this magnificent basin of the Maipo River, when the Spaniards arrived in the 16th century.

"How do we project the regeneration of an 'original' ecosystem so different from the current one, and so much richer ecologically, that it is hard to believe it ever existed?"

Maipo estuary. Photo: Diego AstorgaMaipo estuary. Photo: Diego Astorga
The integrated management of watersheds and water has also been hindered by the sacrosanct private ownership of land and water, which is above everything that gives health to ecosystems. It disregards and commodifies natural goods, including the blessed water, in such a way that in its management "interests" of holders of illusory "rights" are prioritized, although exercising them is destructive of the waters themselves and of everything that those waters sustain. In the same way, with our current paradigm on private property, and the legislation that enshrines it, the owners of large tracts of land can literally do whatever they want with them, regardless of the negative consequences that this decision may have for the local and regional environment, as well as for the entire biosphere. The clear-cutting of thousands of hectares of resilient sclerophyllous vegetation to plant avocado trees is a very present and painful example.
In this country, which is as dependent on water resources as any other, there are no public/community organizations that look after the watersheds from the point of view of socio-environmental well-being, as well as of the diversity and complexity prior to the interventions, which are still their potentials.
The information available on the national territory - the "baseline" - is incomplete, imprecise, cryptic, riddled with technicalities, difficult to access for the general public; so much so that it almost seems that this was intentional, so that we do not know all that we have destroyed and continue to destroy. It is difficult to find reliable sources. Data from different sources often contradict each other. Often, in order to study species or ecosystems, there is no choice but to resort to the environmental assessment studies of industrial undertakings, contracted and edited -redacted- by the same companies proposing high-risk megaprojects, who want the most reductionist and negationist view possible of what will be impacted, as well as of the social and ecological damage that the undertaking will cause.
Although the outlook is bleak, there are many encouraging citizen initiatives, such as the 16 public/private conservation areas -Nature Sanctuaries and Private Conservation Initiatives-, the proposed National Glacier Protection Law that seeks to protect the vital headwaters of watersheds. We want to add to these the campaigns to protect the Ojos de Mar wetlands, at the mouth of the Maipo, and the Quilicura wetlands. Also those in defense of the watershed, No Alto Maipo, No Anglo American and No to the expansion of Los Bronces. The articulation of the Somos Cuencas movement, the work of the Corporación Camino a Farellones and the initiative for the Cajón del Maipo to be declared Geopark by Unesco, the defense of the coastline and beaches, of diverse species such as the Pilpilén and the Andean Cat. And there is more... Faced with the acute crisis in the basin, recently, also the Metropolitan Regional Government, the (CR)2 linked to several universities, and Fundación Chile have become active and are working on the diagnosis of the serious and growing socio-ecological problems that afflict the basin, and in proposing solutions. This is not an easy task, because the problems are of long standing, pushed by a tremendous historical inertia, and because they are structural. In any case, the people are in the lead in terms of being aware and raising the alarm about these situations. It is strange and disturbing, however, that we have to fight to inform and try to protect, conserve, and even revive this basin, which is the matrix of everything that inhabits it. For the Maipo River to flow again, what is crystal clear is that we have to continue working, and with more force and urgency, to improve not only the state of the Maipo River watershed, but of all the watersheds of our battered country called Chile.

Subscribe Today!