RÍO CAUCA: ROUTE, TRIBUTARIES, CHARACTERISTICS, FLORA - GEOGRAPHY - 2024

The Cauca River has the second most important basin in Colombia, being surpassed only by the Magdalena River. It is located to the west of the territory of the South American country, advancing through the central mountain range and the western mountain range.

It runs from the south to the north of the country for 1,350 km, bathing with its waters the departments of Cauca, Valle, Risaralda, Caldas, Antioquia, Sucre and Bolívar. In its journey, it touches 183 Colombian municipalities, which represents 5% of the total of the national territory.

The Cauca travels 1,350 km through Colombian territory. Photo: Alejandro Bayer Tamayo from Armenia, Colombia

The Cauca and its basin have been a fundamental pillar for the economic development of the region since colonial times. There is the heart of the country's sugar and coffee industry. Thanks to its fertile valleys and easy access to water for irrigation, multiple crops of diverse importance for the economy proliferate in the area.

Likewise, livestock, mining and hydroelectric exploitation activities are developed on its banks. All this activity has increased the attractiveness of the region, concentrating 25% of the total Colombian population in its basin.

History

Precolumbian era

The first record of a human settlement on the banks of the Cauca River dates from 1500 BC. C. with the presence of the Ilama culture, which is evidenced by ceramic remains and ornamental metal pieces.

With its evolution and development, various ethnic groups have inhabited the area using the river's waters to obtain their livelihood and as a means of communication with other populations.

Colonial period

In 1535 the first Spanish foundation was made in the Cauca valley, Villa de Ampudia, named in honor of Juan de Ampudia, a Spanish explorer who arrived from Quito in the company of Sebastián de Belalcázar.

A year later, in 1536 Belalcázar ordered the transfer of the town to the western bank of the Cauca. Finally, on July 25, 1536, Santiago de Cali was founded in the Lili Valley and on January 13, 1537, its neighbor, Asunción de Popayán.

After the foundation of the first cities, the river became a fundamental means of communication for the transfer of explorers, settlers and resources that promoted the development of the region.

Contemporary age

In February 1888, the movement of people and goods along the Cauca River in steam boats began. This technology increased the communication and trade capabilities of the river, which, even before its arrival, suffered limitations due to the inability of the workers to move the rafts and barges.

At the end of the civil war, known as The Thousand-Day War, in which conservatives and liberals fought for control of political and economic power between 1899-1902, the Cauca basin was devastated as a result of the bloody confrontations and displacement. of the population.

In 1905, steamship transportation across the Cauca River received a boost from the national government that helped energize and connect local markets. This event coincided with the increase in coffee production in the area, the harvest was taken across the river to Cali and from there by train to the port of Buenaventura for export.

Source and mouth

The Cauca River is born at 3,900 meters above sea level in the Buey lagoon, near the Páramo Sotará in the department of Cauca, located on the Colombian massif. Its channel occupies 63,300 km ² from its source to its mouth in the Magdalena River. The meeting takes place in Brazo de Loba, one of the two divisions of the central sector of the Magdalena River, near the municipality of Pinillos in the department of Bolívar.

Travel

It travels 1,350 km through Colombian territory. From its source in the moor, it sinuously moves south to north, until it joins its waters with the Magdalena River at 15 meters above sea level.

On the banks of the Cauca, multiple settlements have been established on their way north, which depend on the river's waters for their economic and social development.

Alto cauca

This section goes from its source in the Sotará páramo in the Cauca department to the town of Timba in the Valle del Cauca department, occupying approximately 5,451 km ².

Cauca's Valley

It is located between Timba and the municipality of La Virginia in the department of Risaralda. It occupies approximately 19,349 km ².

Middle Cauca

It goes from La Virginia to the municipality of Tarazá, in the department of Antioquia. It covers an area of ​​19,750 km ².

Lower Cauca

It ranges from Tarazá to its mouth in the Magdalena River through the Brazo de Loba, in the department of Bolívar. It occupies an area of ​​18,750 km ².

Main cities that travels

Cali

Capital of the department of Valle del Cauca and the third most populated city in Colombia with 2,401,000 inhabitants, according to the 2012 census. It represents one of the main economic, industrial and cultural centers of the country.

It is a cosmopolitan city that coexists with the river, combining urban areas dedicated to tourism with hotels, restaurants and nightclubs with abundant parks and green areas for recreation and relaxation, promoting contact with nature.

Popayan

It is the capital of the department of Cauca and was founded in 1536. It has one of the best preserved colonial areas on the continent, with more than 200 blocks of period architecture that remain perfectly preserved.

It has Unesco recognitions for its gastronomy and its historical heritage. In 2009 the Easter traditions that take place in Popayán were declared as Oral and Intangible Heritage of Humanity.

With 280,107 inhabitants in 2005, it is a center of great importance for the region. Its urban area is crossed by the Cauca River, dividing the city into two parts with an average width of 40 m.

Tributaries

The Cauca river collects water from the valley that forms between the central mountain range and the western mountain range, made up of rivers, streams, streams and ditches, some of them of pluvial origin.

From south to north it receives the waters of the Negro, Vinagre, Las Piedras, Molino, Sucio, Urbío, Seguenguito, Cajibío, Puente Alto, Nangué, Inguito, Ovejas, Aznazu, Timba, Teta, Quinamayo, Claro, Palo, Tejada rivers. Jamundí, Desbaratado, Cali, Arroyohondo, Yumbo, Zabaletas, Guabas, Yotoco, Media Canoa, La Paila, Chanco, Catarina and La Vieja.

It is also fed by the rivers Guadalajara, Piedras del Valle, Limones, Frío, Tuluá, Morales, Bugalagrande, Pescador, Cañaveral, Risaralda, San Francisco, Pácora, Arma, Poblanco, Cartama, Piedras de Jericó, Combia, San Mateo, Guaca, Niverengo, Quebradaseca, Tonusco, Aurra, Sopetrana, Pená, Santa María, San Andrés, Ituango, Sinitavé, Espíritu Santo, Valdivia, Corrales, Tarazá, Noa, Dentón, Tamaná, Saino, Tigre, Palanca and Nechí.

characteristics

The Cauca River is historically constituted as one of the main axes for the economic development of western Colombia, serving as a means of interconnection between the different populated centers of the valley and as a bridge for its communication with the rest of the country, thanks to the establishment of ports., roads and railways on its banks.

Throughout its basin, economic activities of great importance for the region and the country are developed.

Rain basin

The Cauca River presents two wet periods and two dry periods in its annual regime. The floods appear between April and June; and between October and December. The dry season or dry period occurs first between January and March, and then from July to September. In the rainy season the river presents floods and floods that occupy the valley, affecting villages, farmland and livestock.

Economic motor

In the Cauca river basin are the lands that produce most of the Colombian sugar cane. There are also crops of rice, cotton, oil palm, corn, sorghum, citrus fruits, cassava, banana, coffee, yams, cocoa and beans.

In addition, industrial crops are produced for direct consumption and for processing into different products for human and animal consumption and subsistence artisanal crops. Some of them are permanent and others rotate depending on the season.

The interior plateau of Popayán is a suitable space for livestock exploitation with the breeding of sheep, cattle, horses and pigs. Its open land extensions, the quality of the pasture and the cool climate is ideal for the introduction of imported species that develop better at 2000 meters above sea level, unlike the Creoles.

The banks of Cauca are also rich in minerals such as coal, marble, limestone, silver, gold, iron, platinum and asbestos, which are industrially exploited and have made the Cauca valley the third most important department of mining production. from the country.

Due to the geological and climatic characteristics of the Cauca riverbed, during the winter large quantities of drag sand accumulate, forming islands that are suitable for construction and for complementary use in gardening. Its extraction is carried out in an industrial and artisanal way, constituting an important source of income in the region.

Cultural river

As a partner in the social and economic development of the populations, various cultural activities take place on the banks of the Cauca that place it as the protagonist. Some of them are manifested in ecological festivals, parties, recreational and religious activities.

Hello Cauca River

It is an environmental festival that seeks to draw the attention of the population to the need to preserve this river. This activity is organized by the Cabildo Verde Cauca Limpio, a non-profit civil association that works for the health of the river.

They focus on the sanitation of solid waste and give workshops on the importance and actions to keep it preserved and healthy.

Juanchito Carnival

Part of the cultural heritage of the region, this festival takes place in Cali and celebrates the mixture of cultures that occurred in the area thanks to commercial activities.

The steam transport through Cauca and its sand wealth attracted industrial projects with foreign labor to the area, who settled in the area mixing their cultural background with the locals.

Dancing establishments proliferated that exalted the rich tropical mix, in force to date with great national and international recognition. Other cultural events that take place on the river are:

Cauca River Marathon

This nautical competition is organized every year by the Colombian Federation of Motonautics in the waters of Cauca, in a circuit that goes from La Virginia to Cali and back. The challenge serves to integrate society into river conservation activities, through a dynamic of interest to the whole family.

Procession by the river

As part of the celebrations in honor of the Virgen del Carmen, in July there is a procession along the river in the territory of La Virginia, where the faithful thank the favors received from the patron saint of fishermen, accompanying her image on a walk through Cauca.

Hydroelectric exploitation

In September 1985, the Salvajina dam was inaugurated, the first of the two existing on the riverbed, located in the department of Cauca approximately 170 kilometers from its source.

It was built with two fundamental objectives: in the first place, to control the Cauca flow to avoid flooding in the Cauca Valley during flood seasons. Second, to meet the hydroelectric needs of the valley with the production of 285 MW.

The installation of the Salvajina dam has promoted an important agricultural development in the Cauca valley, allowing the administration of the water resource for its use in irrigation.

In 2010, the construction of the Hidroituango dam began, located in the Ituango municipality of the Antioquia department. Currently the project is still under construction and it is projected that when it comes into operation it will generate 2,400 MW, 17% of the country's total electricity demand.

Environmental impact

Human activity on the banks of the Cauca River has produced changes in the natural conditions of the river, which must be monitored and controlled to avoid the degradation of its ecosystem.

Deforestation

The deforestation of the riverbanks for agricultural and livestock use has as a consequence a significant deterioration of the soil that increases the risk of avalanches and reduces the capacity to absorb rainwater.

Ecological imbalance

Likewise, the elimination of the native flora alters the ecological balance, interrupting the biological corridors used by species that inhabit the region and those that migrate through it.

buildings

The construction of dams, beyond the biological cost due to the relocation of species in the filling of the reservoir, reduces the oxygenation of the water that rests in it. In addition, consequences are generated by the irresponsible administration of the water resource.

This is the case of the Hidroituango dam, located on the Cauca River, recently accused of committing ecological crimes that have caused the reduction of the river's flow.

Through its responsible entities, the Colombian government establishes a minimum limit for the maintenance of the ecosystem, avoiding the affectation of flora and fauna.

For the Hidroituango complex, the minimum was set at 450 m ³ / sec, however, in February 2019 the river flow dropped to 50m ³ / sec, due to the closure of the only downstream water passage, affecting aquatic species and the economic activities that take place in it.

Invasive species

Another problem related to the reservoirs in Cauca is the uncontrolled appearance and proliferation of the Buchón, an aquatic species that in 2019 occupied eight kilometers of the river.

This occurs due to the sedimentation of the reservoirs: the stagnant water contains excess nutrients, which together with the decrease in oxygen in the water, reduces the native species and allows the colonization of others such as the Buchón.

Sand mining

For its part, sand mining increases the presence of fine sediments in the water, which alters the amount of nutrients and salinity present in the water.

Likewise, dredging to obtain sand removes the invertebrates present in the substrate, putting at risk the survival of the species that depend on these microorganisms, undermining the banks and increasing the instability of the terrain.

Contamination

More than 10 million people live in contact with the Cauca riverbed and their cities deposit their wastewater in the river. Added to this is the water that arrives through its tributaries without treatment.

It is estimated that the river receives 330 tons of solid waste daily, which is irresponsibly dumped from adjacent villages.

In addition to receiving poorly treated water and solid waste of a different nature, on its way to Magdalena, Cauca passes through gold mines established on its banks that use mercury to extract the mineral.

This toxic metal seeps through the ground and reaches the river with harmful effects on aquatic species and humans.

The exploitation of coal leads to the water Polycyclic Aromatic Hydrocarbons (PAH) that are released during its extraction and pass into the water.

Unfortunately, in Colombia there is little control of these emissions that are recognized as carcinogenic compounds. PAHs pass to aquatic species and these, when consumed by humans, accumulate in their organisms with effects that are so far undetermined.

Flora

The Cauca moves from 3,500 meters above sea level at its source to 15 meters above sea level at its mouth in the Magdalena River. This gives it a great richness and diversity in the flora it presents. At its highest point it presents wild violet, ericaceous bushes, chusque, terrestrial bromeliads and black soul tree.

Between 2,000 and 1,000 meters of altitude, palms, epiphytes, sapotes, rubber, ficus, monkeys, freighters, beds and large herbaceous grow.

Below 1,000 meters is the humid jungle with trees up to 40 meters, among which the chagualo, yarumo, cedrillo, sande, jagual, carate and walnut stand out.

Fauna

Like the flora, the fauna present in the Cauca River is very diverse due to the great variety of climate that derives from its height. More than 100 species of mammals, 300 species of birds, 30 species of butterflies and 21 species of fish have been identified, in addition to reptiles and amphibians.

Mammals include deer, weasels, skunks, porcupines, howler monkeys, armadillos, squirrels, spectacled bears, sloths, and the mountain tapir.

The group of birds is made up of 13 endemic species and their total represents approximately 40% of the known species in the country, among which there are barranqueros, peeks, hummingbirds, tanagers, bluebirds, guacharacas, carriquíes, canaries, blackbirds, sparrows, owls, owls, toucans, hawks, harriers, crows, parrots, cauca guan, golden feathered parakeet and quetzals.

The most abundant fish in the river are bocachico, corroncho, catfish, toothfish, sweet tooth, and tota.

References

1. Río Cauca: the economic geography of its area of ​​influence, Banco de la República - Cartagena Branch. October 2015. Taken from banrep.gov.co.
2. Historical: they declare the Cauca river as a subject of rights, article in the digital newspaper Semana Sostenible Posted on June 20, 2019. Taken from sustainability.semana.com.
3. Ramírez, Carlos A. Morphological modeling of the Cauca river in the La Balsa-Juanchito section, Engineering and Competitiveness Magazine, 2006, Taken from redalyc.org/pdf/2913/291323467008.pdf
4. Hidroituango dries up the Cauca river: how the controversial dam reduced the flow of Colombia's second river by 80%, BBC News Mundo digital version. Posted on February 8, 2019. Taken from bbc.com/mundo.
5. Recovery of the Cauca river basin, Commission for the recovery of the Cauca river. April 2019. Taken from propacifico.org