Information flow

How does it work?

The transmitter unit is placed on the river bank (at a point where water level reaches during flood) and the receiver unit is placed in a house of the nearest village. The house owner (known as caretaker) will take care of the unit and disseminate information received from the instrument to the downstream communities through mobile phone/SMS.


  • As the power supply is connected to the units (transmitter and receiver), the transmitter establishes its network and starts communicating with the receiver at one-minute interval indicated by a blue LED light in the receiver unit.
  • As the water level rises up to the first sensor segment, the transmitter transmits this signal to the receiver and the receiver interprets it as level one indicated by yellow LED light.
  • If the water level rises up to the second sensor segment, the transmitter transmits second level signal to the receiver and the receiver interprets it as level two indicated by orange LED light and beep siren as pre alarm.
  • If the water level rises up to the third sensor segment, the transmitter transmits third level signal to the receiver and the receiver interprets it as level three indicated by red LED light and continuous ringing siren as final alarm.

Information flow

Disseminating and communicating risk information to the concerned communities and authorities is the integral part of the CBFEWS. When flood signal is detected upstream, it needs to be disseminated instantly so that people can prepare and respond to it. Warning information must be clear and brief for people to understand it. The followings are the major components of information dissemination.

Source of early warning information

Early warning information comes from individuals or organizations that generate a risk message and send it to concerned authorities and vulnerable people. The caretaker is the main source of information within the CBFEWS. Every bit of information delivered from the source needs to be reliable, timely and consistent. The source person (caretaker) needs to formulate a clear and standardized warning message so that the intended recipients can fully understand the message and act accordingly.

Recipients of early warning

Warning recipients are nodal persons downstream who are part of the communication network and who receives the warning message from different channels (e.g., directly from the source such as a caretaker or other concerned authorities) and instantly communicate it to the household level. There will be various levels of recipients depending on the distance of the vulnerable settlement along the river and the urgency of delivering the information.

Early warning message

Warning message is the information sent from the source to the intended recipients in the form of text (e.g., SMS), verbal or sound (siren, telephone, megaphone, shout, etc.) and visual (colour, flag, sign). When flood occurs, the situation does not allow for lengthy conversations. Warning messages should hence be short, concise, understandable and consistent and tailored to the specific need of intended users. Use of code language, e.g., ‘water reached level 1’ or ‘flood level 1’ can shorten the message. But such code language must be explained to the intended message recipients beforehand. In other words, the recipient should know what ‘flood level 1’ means, how to respond to it and what precaution needs to be taken. The CBFEWS developed by ICIMOD has three warning levels that can interpreted in the following manner.

Communication Channel

Communication channel is the network of people created for information dissemination. An efficient and reliable communication network is important for CBFEWS. Communication network, particularly among upstream (caretaker) and downstream (concerned people and authorities), is of utmost importance, and it should be formed in the initial stage of implementing the system. It can be formed through stakeholders’ consultation and meetings with local government officials and influential people in the village.

Key Actors and Their Roles and Responsibilities

The major actors in the communication network for CBFEWS are the caretaker of the instrument or gauge reader, local governmental authorities including army, police and disaster response units, village/panchayat heads and influential people, scientific or relief organizations, the media, and individuals who are concerned about the disaster. Each and every actor should have predefined roles and responsibilities that they would perform before, during and after the disaster. The major actors and their roles and responsibilities are listed below.


  • Take care of and monitor (e.g., check, clean and troubleshoot) flood early warning instruments
  • Monitor flood levels, keep records and disseminate flood warnings to the concerned authorities and people
  • Regularly report on the status of the instruments to the concerned authorities and communities

Local Disaster Management Authorities

  • Monitor and cross-check the situation, circulate information to the concerned organizations and downstream focal persons.
  • Deploy flood response or rescue teams such as military, police and civil authorities to the affected areas.
  • Circulate information to different media organizations.

Focal Person (Recipient of Information) in Downstream Vulnerable Villages

  • Receive flood warning and communicate it to the grassroots level.
  • Make sure that each and every member of the community gets the warning information.
  • Coordinate and disseminate information to different people who are responsible for different task for example early warning, rescue, first aid etc.

Local Media

  • Alert community by broadcasting or publishing flood warning and information.
  • Inform the community about ongoing relief and response activities.
  • Coordinate with the relief organizations.

Flood Risk Management Committee

In the absence of a community group that can deal with flood risks, a flood risk management committee can be formed based on common consensus to enhance the capacity of the local people to withstand the effects of flood in an organized way. Forming a flood risk management committee can not only unite the whole community and strengthen their capacity but also provides the authority and leadership for dealing with local flood related issues. The committee can have several sub-committees like early warning, communication and information group; first aid and heath group; evacuation and rescue group; shelter management and logistics group, etc. The major roles and responsibilities of flood risk management committee are:

  • Plan, implement and monitor flood related issues.
  • Coordinate and establish a network with external agencies and stakeholders.
  • Coordinate with upstream community
  • Coordinate with local people and assign them for different responsibility
  • Prepare a flood preparedness plan

Other actors

The private sector, Red Cross Society, police, army, influential leaders, and local teachers are other actors involved in disseminating the early warning.

Contact us

Neera Shrestha Pradhan
Water and Adaptation Specialist