tomenu
Local warning system – flood warning and forecasting system
LVS (Local Varning System) servesto warn the population against flooding. Especially before the torrential rains (eg storms). It consists of several individual measurement stations and the central station. They are divided according to the measured values :
- Rain gauge measuring station
- Hydrometric measurement station
In Slovakia, the system is running for example in the village, which is in the mountains surrounded by hilly terrain. Similarly situated municipalities in Slovakia is a lot, but the problem is that this terrain is grassy. In other locations the water that flows down the slopes after torrential rain is captured by the forest and soil. The water on the grassy surface sinks into the valley where the river level dramatically increases, and overflowthe village. In the surroundings, on the hills are strategically placed rain gauge stations to measure rainfall. Usually two or three rain gauge stations (depends on terrain). In front of the village by the stream is positioned gauging stations that measure the water level in the stream.
Each station isautonomous, is powered by battery and the electrical connection 230 is not necessary. The battery is recharged by the solar cell. The ERAN 2 is used in the station. It provides the following features:
- viewing the current results on the display
- it remembers the measured data for aperiod of 1 year
- configuration by keypad
- setting of 3 limits of precipitation and 3 limits of water level
- communication with WinCentral through GSM network (if there is no possibility of
GSM Access ,
communication is privided by radiostation)
- sends warning SMS in case of limit excession on telephone numbers
Water level station measure water level in the creek in fron of village. The measuring interval is 5 minutes, so every 5 minutes is the water level measured in the stream and the measured value is compared with four different limits. In excess of any limit, the station sends a warning message.
Rain gauge station measures rainfall (precipitation). Every 5 minutes station evaluates whether the limit is not exceeded. The station evaluates the four levels. Rainfall for the last 5 minutes, 30 minutes, 60 minutes, 12 hours. In the case of limit excess, the station sends a warning messages.
The centralstation isusually located at the municipal office of the village. Central station is a computer that is running a WinCentral and SQLView (Visualis) with the following features:
- WinCentral communicates with the stations, downloads data from them and warning of
limit excess, controls the functionality of stations
- SQLView presents measured data
The stations communicates with thecentral station via the GSM dial-up connection or via radio. Advantages and disadvantages of these types of communications are listed below.
Radio-communication:
- if there is no GSM network,- only one option
- I tis necessary to provide the permission for communication zone
- There is no fee for transfered data, but there is fee for communication
zone permission
- In case of limit excess is warning message sent to the central station and central
station sends the sms to default telephone numbers
GSM dial-up:
- i tis not necessity to provide communication zone permission
- obligation to obtain SIM cards with data number
- fee for transfered data
- needs to be access of GSM network
- In case of limit excess, warning messages are sent directly to telephone number
without communication with central station