The Andean Glacier and Water Atlas

CASE STUDY

An early warning system for potential glacial lake outburst floods in the Cordillera Blanca, Peru The glacial lake Laguna 513 (9°12 ' 45 '' S, 77°33 ' 00 '' W) is located in the Cordillera Blanca at 4428 meters above sea level, in the tropical Andes of Peru. This and other glacial lakes sit in the catchment of the Rio Santa Valley, which is densely populated, with more than 260,000 inhabitants living downstream. Languna 513 started filling up in the 1970s. Syphoning of water was undertaken in the 1980s and tunnels were built in order to further lower the water level in the lake. However, in April 2010 a rock-ice avalanche entered the lake, causing a GLOF which damaged several bridges downstream and covered agricultural land. Fortunately, in this case no lives were lost. Based on insights from retrospective modelling analysis of the 2010 GLOF and hazard mapping on potential future scenarios, an early warning system was developed. The system consists of four stations, each strategically positioned. One station sits at the lake itself and a second station located at 3,600 m includes a pressure sensor. Both stations are equipped with geophones (devices recording ground movements and converting them into voltage). These are the main instruments used to register a potential GLOF trigger. Additional instruments include a camera at the highest station taking photographs every five seconds, and other sensors that measure humidity, wind speed, air temperature etc. The third, repeater station sits at 3,200 m and the fourth station, the data centre which receives all the information, is located at 2,600 m. In the event that one of the geophone passes over a certain threshold, an SMS is sent automatically to all involved persons, advising them to immediately check the early warning data and information. Subsequent steps have then to be taken based on a pre-defined action plan and on the available data. The early warning system is part of a larger initiative by Care Peru, which included education and capacity building measures on climate change adaptation. When installing systems like this, it is very important to actively engage with the local communities to ensure that they understand the benefit of these systems. In this case, the early warning system was destroyed by local farmers because they believed that the system caused the droughts that they are experiencing.

Policies andapproaches toaddresswater security in the Andes Adaptation at the local and community level needs to be supported by actions, including appropriate national and regional policy, trans­ boundary cooperation and international action on climate change. In many cases, local level approaches may be insufficient for water conservation and management. This is because water resources in the basin are impacted by several factors that extend beyond the local area, such as agriculture, urban development and forest conservation. And equally, the water resources affect the human activities in the areas surrounding the basin. Approaches such as river-basin Integrated Water Resources Management can be used to ensure that the linkages between the management of water and land are addressed, giving all the stakeholders within the river basin area an opportunity to improve coordination and operation (UNESCO-International Hydrological Programme, 2009). National policies need to provide strategies, plans and actions that address adaptation in key sectors such as sustainable water usage, agriculture and energy. National policies must also recognise the gender and ethnic inequalities that exist, to ensure that marginalised groups are considered and accommodated. The failure to develop policies that acknowledge potential impacts of climate change on mountain environments and related sectors will hinder economic development and will certainly result in loss of livelihoods at a local level and possibly at a much broader scale (Schoolmeester et al., 2016). A number of Andean countries have also taken up specific policy and legal measures to protect mountain water resource ecosystems and glaciers themselves. For example, in 2014, the Peruvian Congress passed the Payment for Ecosystem Services Law (the “PES Law”). The Law aims to promote, regulate and supervise the Payment for Ecosystem Services schemes (the “PES schemes”) to ensure the

Sources: Frey et al. (2014) & Hill (2016)

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