OPINION: How to avoid turning Peru’s capital back into a desert

Belén Desmaisón, from the Pontifical Catholic University of Peru, analyses water stress in Peru’s coastal towns with a focus on Lima, where 75% of the water supply comes from the Andean glaciers. These glaciers, as detailed in the IPCC Special Report on Oceans and the Cryosphere, are currently disappearing.

CDKN invited specialists from the Global South to give their opinions on the IPCC Special Report on the Ocean and Cryosphere in a Changing Climate (SROCC). They answered the question: What are the implications of this information for their regions or countries, and what is their opinion on future development?

Half of Peru’s population depends on water supplied by glaciers

Peru’s coastal cities and towns all have an age-old connection with the ice from the Andes, as the glaciers supply water to the rivers that sustain coastal valleys. Over the centuries since pre-Hispanic eras, different civilisations have dug canals to expand the agricultural areas around these rivers to make one of the most arid deserts on the planet habitable. Lima receives only 10mm of rain annually. As a result of these immense efforts to convert arid terrain into productive valleys, currently almost one in three Peruvians live in the capital Lima. It is known as the second most habitable desert city on the planet (second to Cairo, Egypt).

The recent IPCC Report on Oceans and the Cryosphere in a Changing Climate foresees the rapid and continuing disappearance of year-round ice covering the White Mountain Range in the South American Andes, even without an increase in temperature. In Peru alone, 42.64% of the glaciers have disappeared in the last 40 decades. Consider that 75% of the water supply to the population of Lima (almost 10 million people) comes from the Lurín, Chillón and Rímac Rivers, which are entirely dependent on rainfall in the high Andean regions adjacent to the capital. The city is set to experience a growing water crisis that requires urgent adaptation measures in order to deal with the challenge.

Water use in Lima: Inequality and abuse in consumption

As with many other cities in the region, Lima is a city with high levels of inequality, and this includes the access to and daily use of water in different areas. More than a million people in Lima are dependent on delivery of water in private trucks for their water supply. According to Oxfam, they pay ten times more per litre than those who have fixed twenty-four hour water connections.

Furthermore, the National Superintendent of Sanitation Services reports that a person living in San Isidro, one of the most affluent districts, uses 400 litres of water per day while a person in Villa el Salvador, a more socio-economically vulnerable district, uses no more than 79 litres per day. These calculations may contain some inaccuracies, as they do not take into account the use of water by the transient/homeless population, industry and maintenance of public spaces. Nevertheless, the figures do reveal stark inequalities and the need for a more equitable distribution of water resources.

Bearing in mind that the World Health Organization states that a person should (be able to) use 100 litres of water per day to cover all necessities, in order to prepare for the growing water stress it is therefore not enough to only promote increased access to water for the most vulnerable populations but we also need to raise awareness and promote more efficient use of water in the wealthy areas. There needs to be a balance in water consumption in the city, so that the rivers can sustain demand. It is impossible to attempt to supply 400 litres per day to all inhabitants in Lima.

Adaptation measures must be connected to more efficient use and more equal access to water

To guarantee adaptation measures to deal with the imminent water crisis, the city needs radical changes in water and sanitation governance. It therefore needs to implement policies, programmes and specific actions to promote more efficient water use and more equitable and fair access.

The first step is to raise public awareness of the need to reduce water use and to encourage the use of more efficient fittings for toilets, taps and showers. This could go hand-in-hand with a tariff-scale based on water usage to discourage excessive consumption.

In addition, it is important that there is ongoing promotion and implementation of policies and programmes that oversee maintenance of water infrastructure (preventing leaks) and treatment and recycling of grey water.

SUNASS has re-used water for activities such as irrigating green areas, industrial uses and for toilets, which is less costly than treating water for (human) consumption. Beyond domestic use, actions must be taken to tighten the control of water usage (both legal and illegal) in the mining sector, to prevent wasting and contaminating the water source.

Finally, water management programmes and actions need to be multi-sectoral and multi-scaled, and this requires restructuring and inter-institutional collaboration. This would improve the participation of sub-national governments and enable greater control where currently they have very limited capacity. It would also provide an essential systemic framework that would make it possible to view the problem more holistically by assessing the total water catchment, and the repercussions on the entire system of actions taken in specific areas.

In conclusion, there is an urgent need to adapt to a future of water scarcity, which may impact more than just the situation of Peru’s coastal cities. Implementation of these measures requires commitment and collaboration from the state, private business, academia and the population as well as continual consolidation of networks for knowledge exchange and spaces for discussion.