Innovative and sustainable sanitation services to ensure access, closure of the nutrient cycle and as a measure of adaptation to climate change

Nitrogen and phosphorus are essential for food production in global agriculture. A food security assessment should consider whether there are sufficient nutrients to ensure food production. With a growing world population, the food needs of an additional 2 billion people will need to be met by 2050. In this scenario, innovation to find new sources of nutrients to ensure food security is even more relevant.

Worldwide, the discharge of untreated wastewater into rivers and seas represents a negative environmental impact and is risky for public health. The Sustainable Development Goals (SDGs) provide guidance to countries to advance sanitation, achieve better living conditions and protect the environment.

In Bolivia, the population has grown rapidly in the last two decades, and is expected to continue increasing in the future. Although 68% of people have access to sanitation in urban areas, only 30% of wastewater is treated [1] and the city of La Paz, the most populated, does not have a wastewater treatment center.

The Metropolitan Master Plan for Drinking Water and Sanitation of La Paz – El Alto and Adjacent Areas establishes as a general objective to establish the best strategy for the development and expansion of drinking water and sanitation services until the year 2036. The plan includes sanitation alternatives in -situ, through the execution of ecological sanitation for populated areas that demand attention to their sanitation service needs.

The Embassy strengthens relations between Sweden and Bolivia, promotes political dialogue and cooperation for sustainable development. Thanks to their support, an exchange of Swedish technologies for the crystallization of urine was generated in the municipality of El Alto (La Paz) with the purpose of obtaining a powder fertilizer with a high content of phosphorus and nitrogen, two key elements for food production. This presentation (powder) facilitates the application of the fertilizer for Bolivian farmers. Although the innovation and technology are Swedish, work was carried out to adapt that technology to the Bolivian context with local materials.

EPSAS, the operator of drinking water and sanitation services in La Paz, with the support of the Swedish Embassy through the technical assistance of Aguatuya, is developing capabilities to offer innovative sustainable sanitation alternatives, such as decentralized wastewater treatment , septic tanks with scheduled collection of sludge for proper treatment and management of waste from dry ecological toilets, implementing an adequate system for the collection and treatment of fecal sludge and urine until its final disposal, ensuring its continuity, the closure of the cycle of nutrients and sustainability.

It is expected that this set of additional solutions will allow EPSAS to provide an innovative, accessible and environmentally sustainable sanitation service for peri-urban populations and even contribute to closing the nutrient cycle and food security in Bolivia. Based on current crop yields, the nutrients available in human excreta could meet the 100% nitrogen and 70% phosphorus deficit. Therefore, excreta recycling could be one of the most innovative strategies to prevent deforestation and nutrient depletion in forests and also increase the circularity of nutrients and crop yields in Bolivia.

[1] Source: National inventory of wastewater treatment plants carried out in 2017 by the Ministry of Environment and Water of Bolivia.