Floods are caused by many factors like prolonged heavy rainfall (locally concentrated or throughout a catchment area), highly accelerated snowmelt, severe winds over water, unusual high tides, tsunamis, or failure of dams, levees, retention ponds, or other structures that retained the water. Flooding can be exacerbated by increased amounts of impervious surface or by other natural hazards such as wildfires, which reduce the supply of vegetation that can absorb rainfall.
Climate extremes and changing weather, which are associated with global warming, have led to a significant increase in the frequency and severity of floods. Flooding has many negative impacts, damaging property and endangering the lives of humans and other species.
Some methods of flood control have been practiced since ancient times. These methods include planting vegetation to retain extra water, terracing hillsides to slow flow downhill, and the construction of floodways (man-made channels to divert floodwater). Other techniques include the construction of levees, lakes, dams, reservoirs, retention ponds to hold extra water during times of flooding.
If a construction site, property or community is at risk from river flooding, having an early warning system in place could make all the difference. Time is crucial to deploy some flood protection measures and to remove people, vehicles, machinery and vulnerable materials to a place of safety.
Local Environment Agencies’ flood alerts often have been proven unreliable, so when flooding does occur, affected areas are not ready. With remote river flooding monitoring and alarms in place you can be sure that everyone who needs to be alerted will be, whenever the flooding actually occurs. But the effective implementation of flood monitoring and warning system is non-trivial, since it requires the reliability coupled with the availability of related information.
Water level and precipitation measurements, together with video surveillance is an excellent way to control the flood risk. Other sensors to measure soil moisture, water quality, or meteorological conditions like wind speed, wind direction, humidity or solar radiation can sometimes add valuable information.
Real-time images provide more useful dynamic field information to support improved decisions than sensors alone.
Water level sensors using radar technology provide a way to measure depth in areas unsuitable for contact-based depth sensors such as submersible pressure transducers, allowing for monitoring in hard to reach locations.
The ideal placement for a flood warning gage will depend largely on the site considerations of the waterway where it is located. Careful planning is needed to select the location, determine water level fluctuation, and to design a mounting solution that will effectively protect the gage from acts of nature or vandalism.
NIHON KASETSU eComo Monitoring System can be installed and operate from a single or multiple locations, with flood sensors distributed over areas measuring many square km/miles. Warnings to staff and public can be delivered using a variety of media including e-mail, SMS text, audible siren and flashing lights, etc. Our wide experience in this kind of application can help you find the optimal solution for your projects.