Flood monitoring system under accurate hydrological model It is a project that brings together knowledge in many disciplines. The objective is to solve problems and find ways to prevent or mitigate the severity of the flood that will occur. That will affect the economy, health, homes or property or agricultural areas Which, when considered the value of the damage, is very mental and economic Floods can be divided into 2 types: flooding in the community area or the city. And floods in agricultural areas or around the city To solve the problem of flooding must be viewed as a system and a single block. Cannot fix only any part of the problem Must solve problems at the same time Hydrology models are therefore important. To understand the system and pattern or the amount of water that will occur This starts with the amount of rainfall that will occur in the area as well as statistics of the rain in the past. If there is a rainfall that falls beyond the capacity of the water catchment area (Watershed Area) or the river (River) will cause excess water causing runoff from the conditions of the hydrological system or various variables. That have caused a flood As mentioned above If we can know or measure variables and accurately process the mass of water that will occur. This information can be used to design a surveillance system and determine how to manage future floods. Internet of Things (IoT) or the Internet of Things It connects many devices into the Internet world. Making it possible to command, control or monitor various devices through the Internet It makes it more comfortable, shorter, and easier. Moreover, nowadays, IoT technology is playing an increasingly important role in human daily life. Whether it is agriculture, military, transportation, etc. But IoT still has problems in connection due to the connection to the Internet. Because some or some places are distant Causing poor internet access And including the need to have an adequate power supply to meet the needs of the system. Therefore, NB-IoT (Narrow band Internet of Things) technology is applied to solve this problem, as NB-IoT is the latest standard for connecting various IoT devices to mobile internet without 3G / 4G. NB-IoT is low power consumption. Can use energy from Solar Cell by reducing the panel size. Support for connecting multiple devices simultaneously, can be used both indoors. And large areas The device is cheaper, easy to use, works through networks that have already set up towers. Therefore, the project to create a flood surveillance system under the correct hydrological model. It is a project created to study and integrate principles Hydrological data Land use information Surveillance network information system And how to monitor the flood with IoT technology with the appropriate guidance To be used primarily in water management, whether it is the management of floods that affect urban communities. Or farmers community In that area correctly and able to answer spatial problems (Area Based) properly By adopting NB-IoT technology as a medium for connecting to the Internet world more easily. Make network information system surveillance And surveillance of floods is easily accessible and convenient to the user.