Early warning of flood conditions is vital to avoid any personal safety incidents and to mitigate damage to crops and infrastructure generally.
Careful measurement of upstream river levels assists with predicting flood levels and the timing of flood peaks. Alarm systems which alert key staff allows for better planning and reduces the impact of flood events.
A resilient and redundant telemetry system is crucial for such systems. In flood events local power and local cell tower infrastructure may also be damaged by the flood event. The telemetry systems using satellite infrastructure and systems with independent power systems are the best to ensure the measurement stations survive the flood event.
River level monitoring is routine and can be achieved through various methods, the most common being on a float and pulley / shaft encoder instrument at a convenient point inside a stilling well. Unidata’s 6541C is an appropriate instrument for this purpose.
A Neon Remote Logger can be used at each level monitoring station to read and transmit the river level data to a Neon Server routinely, typically every 5, 10 or 30 minutes. When the data arrives at the Neon Server, it can be viewed on a standard web browser. The data can be checked automatically for any out of limit / any high river level readings and an appropriate alarm action can be set up. Typically a high level could cause an email or a text message to be sent to key staff, and the messages can be set up with escalation processes, if the operation does not acknowledge the alarm. In these circumstances, the alarm will be sent to other staff on a hierarchy basis until one person acknowledges the alarm. Monitoring stations may also include a camera, either low definition image, high definition image or low frame rate video to provide further feedback as to the river conditions.
In flood conditions, primary power often fails, so the river level monitoring instrument and the Neon Remote Logger should have an independent power source, typically this would be a solar panel and battery, and perhaps a lithium emergency battery as a further power backup.
Consideration should be also given to the choice of communications channel for the Neon Remote Logger. In flood conditions, cell towers are also at risk of failure. If a cell tower fails in a region, its failure could cause several measurement stations using that cell tower to fail also. A satellite based system eliminates this risk and should be considered for some river measurement stations.
A river measurement station could also be set up for a Neon Remote Logger to use the cell tower as the primary communications channel and another satellite based channel could be available as a backup to make the system more resilient.
During flood conditions, it is often important to illuminate warning lights / warning signs and or audible alarms. The Neon Remote Logger can be configured to provide such control functions on local alarm and / or on a command from the Neon Server.
