Community-centred flood early warning system in Nepal

South Asia Nadi Sambad

Early Warning Systems should aim to integrate the concerns of local people and be inclusive of gender, cultural, linguistic, and other social aspects.

By Dinanath Bhandari

Flood disasters cause significant loss and damage in Nepal. In an effort to minimize the impacts of flood disasters, strategies for risk reduction, including community-based flood early warning systems (EWSs), are being developed. Over the last 15 years, such EWSs have been established in over one dozen rivers in Nepal. Many individuals, communities, and government and non-government organizations are working on further developing them.

Rivers of Nepal (Credit: Regan Sapkota. Drawn with data from Department of Water Resources and Irrigation)

The typical EWS has four key elements:

  1. Understanding risks,
  2. Monitoring risks
  3. Communicating risks, and
  4. Responding to available risk information to prevent losses and damages.

A typical EWS includes weather monitoring, rainfall measurement, flood monitoring, and flood risk-forecasting arrangements. Similar to other technologies, these systems have been transformed from manual configurations to more efficient forms using ICT.

In this paper, I briefly discuss the evolution of community-based flood EWSs in Nepal and the challenges they face in better serving the risk-reduction needs of vulnerable communities.

The First Community-Based Flood EWS

The EWS located on the bank of Nepal’s East Rapti River in Chitwan District is Nepal’s first community-based EWS. The EWS was established in Bhandara in 2002 and subsequently set up in Piple and Jagatpur in 2006. This system used a machan, an elevated platform built to observe wild animals such as rhinos, deer, and wild boars from Chitwan National Park crossing the East Rapti River to entering human settlements and agricultural fields in the villages of Piple, Bhandara, and Jagatpur. One person from the community would, in turns, watch from the machan and raise an alarm if he/she saw animals approaching the villages. The villagers would then chase away the animals and save their crops.

East Rapti River in Chitwan District faces frequent floods during the monsoon and the 1993 floods brought especially large-scale devastations. The communities living along the banks of the river wanted to participate in an effort to minimise flood losses. From the machan, the observer would also watch the river and its flood level. The person would inform downstream communities of a potential flood so that they could take measures to remain safer from the floods. Thus emerged the idea of a community-based early flood warning system. For the 100 days or so of the monsoon, villagers would watch the river level from the machan. Once the river water reached a certain level, they would convey the message to community volunteers who would then go from door to door and inform the locals about the potential flood.

This arrangement worked well but faced two major challenges. First, at night, the person on the machan used a torchlight to observe the river but visibility was too poor to make accurate readings of the river level. Second, visiting every household to convey the message about a flood took time and was a difficult task. These limitations were overcome by using high-power electricity-operated flashlights to improve their view of the river. To inform people about the floods, electric sirens were introduced. New challenges later emerged to challenge these developments, too. During 2006/2007 Nepal faced frequent and long power cuts. As a result, neither the electricity-operated flashlights nor the siren worked adequately.

The problem posed by the power outage was solved by using a rechargeable acid battery torchlight. For informing the downstream communities a hand-held and -operated siren was introduced[1]. In addition, hand-held megaphones and mikes were used as an effective means to disseminate messages about flood levels. Both sirens and megaphones are still used to communicate flood risks, but communities also receive information from upstream gauge readers and SMSs from the Department of Hydrology and Meteorology (DHM).

Digital Methods

The advent of asymmetric digital subscriber line (ADSL) and mobile telephones has helped update EWSs. Since 2007, the DHM has used these devices to inform downstream communities of incoming floods. In the East Rapt River, the DHM observes the flood level at the gauging station at Rajaiya, which is located about 50 km upstream of Piple. The flood levels measured at Rajaiya are transmitted via mobile phones to downstream communities and to the local early warning task force with at least two hours of advance notice. The communities are encouraged to move to emergency flood shelters if necessary. Today, using advanced communication technologies, the real-time water level of the river is displayed at the District Administration Office in Chitwan.

By 2010, EWSs had been established in the West Rapti, Babai, Mohana, and Karnali rivers[2]. In 2012 an avalanche on Annapurna mountain caused flooding in the Seti River in Pokhara, which, in turn, lead to the loss of life. A year later, in 2013, with funding from the UK government, the DHM set up a river-level sensor and a climate station as part of the EWS in the Seti River. The station monitors and communicates real-time rainfall and river water-level data to downstream communities, a display board, and the District Emergency Operation Center at the district administration office in Pokhara.

In 2014, with support from USAID/OFDA, an EWS was established in the Kankai River in East Nepal. Established in partnership with the Jhapa District Chapter of Nepal Red Cross Society, the EWS uses the concept of providing rainfall-based flood alerts. New rainfall stations were also established in the river’s catchment in the mountain and the data collected was used to calculate potential floods by using a rainfall-runoff model. Later in 2016, a similar approach was established in the Kamala River basin with flood monitoring stations in those parts of Sindhuli, Siraha, and Dhanusha districts in the river’s catchment. An EWS has also been established in Koshi River to warn flood-vulnerable communities in Sunsari, Udayapur, and Saptari districts. It uses flood levels measured at Chatara. District chapters of the Nepal Red Cross Society partnered in this effort.

Since 2014, Nepal’s DHM, in partnership with the regional forecasts of the meteorological offices of other South Asian countries, issues three-day forecasts of rains. The DHM also sends messages of high rainfall and consequent high floods to downstream communities using radio, television, mobile phone, internet-based social media (Facebook, Twitter, and the like), and telephone.  During the monsoon, to get information on flooding, one can also call the toll-free number 1155.

Local Disaster Management Committees

Flood risks are a result of flood hazard exposure and vulnerabilities. To lower risks, community disaster management committees and local governments must be involved in risk reduction actions. EWSs are key in this effort. It is also important to recognise the context of the communities that receive messages meant to save lives by helping these communities move to places safe from flooding. Not everyone in a community has the same status. Depending upon the language, culture, age, and disability, individuals have different abilities to understand EWS messages. Making the decision to move a community is difficult.

Every year in every EWS site community volunteers are trained and mock-flood exercises are held. Flood-prone communities are mobilized to go to safe flood-shelters and locations as a key part of the actions. Since 2016, the National Emergency Operation Centre, the DHM and the respective district disaster management committees, and local authorities have also participated in these exercises. The mock-flood exercises use mobile text messages of flood alerts and warnings sent by the DHM. The exercise involves harmonizing text messages, blowing sirens, using loudspeakers, showing blue, yellow, and red flags, and visiting communities at risk. The time it takes to convey text messages to communities and disaster managers are also assessed in the exercise. Such exercises help in better understanding how users respond to early warning messages during a flood disaster.

In addition to saving lives, a community-based flood EWS also helps local communities take movable assets such as small livestock to safety before a flood arrives. To minimise risks, the community members who receive warning messages should be vigilant. They must keep grains and other materials in places where the floodwater will not reach before they leave their houses and go to the designated emergency flood shelter. The more time that is available before a flood arrives, the more that can be done to lower risks to the affected community. People with disabilities, sickness, and other limitations should receive special consideration during evacuations and other responses.

In their design and implementation, all EWSs should aim to integrate the concerns of local people and be inclusive of gender, cultural, linguistic, and other social aspects. Disaster management officials should heed the nature and magnitude of hazards and the specific needs of the communities. Some in a community may need immediate help but others may not. In order to achieve the goal of minimising risks, an EWS is basic, but it is equally important to work with communities to save lives, properties, and livelihoods. While these challenges must be systematically addressed, the EWSs established in Nepal have helped reduce human casualties.


[1]     This siren was brought from Maharashtra, India.

[2]    Practical Action and its partners and others were involved in the development. The European Commission’s Directorate General for European Civil Protection and Humanitarian Aid Operations (DG ECHO), formerly known as the European Community Humanitarian Aid Office, supported the community-based EWS.

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