Context
“En poco años, no habrá nada. El Lago Titicaca está enfermo, nosotros también.”
In the words of natives “In a couple of years there will be no life. Titicaca Lake is ill, and so are we.” The declaration belongs to the people living in Bahía de Cohana, Bolivia and it was released as the community resolution, in order to mark the Water International Day, in March 2012.

Titicaca Lake is the "highest navigable lake" in the world, shared by both Bolivia and Peru, and one of the most attractive touristic areas, while Bahía de Cohana is an area located in the Minor Lake of Titicaca.

The lake’s watershed is suffering, already for decades, the effects of climate change and pollution from residential, industrial and mining effluent. The large infrastructure developments in the city El Alto and surroundings mirror downstream significant climate changes: rainfalls carrying effluents in the bay area, water eutrophication and livestock farming endangered.

Thirty years ago, fishery and agriculture were the principal form of survival, but today, due to pollution, the fishery has disappeared and the agriculture is suffering from soil degradation. The eutrophication (over-nitrification) is a common issue in areas with rapid growth and large developments. Bahía de Cohana, where livestock farming is the main economic activity, providing life resources for thousands, is at risk.

Progress
Addressing the needs of small and vulnerable countries is one of the missions of the Inter-American Development Bank (IDB), which works to improve lives in Latin America and the Caribbean. Started in the 60’s, Bolivia has been assisted by IDB in its national evolution, due to its geographical constraints and legacy of poverty.

Large investment projects in transportation and energy sectors are complemented by actions for assessing their impact and adaptation to climate change for both people and nature. Such evaluations will be difficult to be done by using ground access for large workforce, but technologies based on remote sensing are efficient alternatives, and assessments can be done periodically without extensive preparation.

For more than a decade, Sentinel satellites from Copernicus programme are supplying huge amounts of data. The European Space Agency (ESA) has initiated collaborations with international financial institutions, in order to demonstrate the capability and the efficiency of high quality geo-information services.

In 2015, TERRASIGNA was commissioned by ESA to perform an impact analysis for IDB’s investments in South America.
There were several case studies addressed in Bolivia, and Bahía de Cohana was assessed through a detailed investigation focused on the bay area, and the two river basins feeding the zone. The analysis took into consideration the larger context:

• area of interest - 5078 sq. km;
• almost 1 million people in the range studied (including industrial areas);
• hydrographic network - 9 lakes (5 with small dams, 4 with natural flow) and 2 main rivers (Katari and Tiahuanacu);
• urban areas - 9 important cities with El Alto the largest, industrialized;
• environmental issues - polluted waters from various cities feeding the Titicaca Lake.

The study covered the period 2003 - 2016, but land use dynamics were also performed for various temporal periods.
Change analysis monitored key aspects in the area of interest, associated with different datasets:

• urban extension - increased;
• aridity - decrease trend;
• seasonal changes - rain fall (decrease tendency) & mean air temperature (rise trend);
• vegetation overgrowing - vegetation indices (declined) & evapotranspiration (deteriorated in the extended agricultural areas);
• agricultural expansion - increased.

Large urban spread and agricultural expansion were made at the cost of sparse vegetation and wetlands, which play an important role in everyday life.

Natural resources exploitation is a blind trade-off, especially in underdeveloped countries, but balance defines life on earth.
Every being has a role to play and exists only through the existence of another being. A subtle, fragile harmony that can be easily shattered.

Financial institutions and companies seeking the impact of their development plans have now a trusty ally.  
EO technologies are an efficient operational support tool, assisting investments plans all through its deployment stages.

This is the first material in a serie that will present services performed in South America.
See also Lake Titicaca water quality assessment and High Andean Wetlands