# A Real-Time Water Level and Discharge Monitoring Station: A Case Study of the Sakarya River
## 4 Discussion  
The real-time river monitoring station represents a significant innovation in environmental monitoring technologies, providing accurate and continuous measurements of river water levels. This system transmits measurement data to a server via the internet using microcontroller and Internet of Things (IoT) technology. The design, functionality, and application potential of the system are assessed based on its energy independence, integration of advanced technologies, communication and software infrastructure, and calibration processes. One of the most remarkable features of the monitoring station is its energy independence. The integration of a solar panel and Maximum Power Point Tracking (MPPT) solar energy control unit allows the system to operate autonomously without the need for an external power source [34]. This design reduces operational costs and enhances the system's reliability in remote or off-grid areas. The ability of the system to function for approximately a week solely on battery power, even without solar input, demonstrates its durability and robustness under varying weather conditions. This feature provides significant advantages in terms of sustainability and uninterrupted data collection, which are critical for effective environmental monitoring. The ultrasonic liquid level sensor used in the system ensures high accuracy in water level measurements [35]. This sensor can measure river levels at specified intervals and transmit the data to a central server via the GSM module. The use of an RS485 converter for data processing and transmission further enhances the reliability and accuracy of the data flow. The communication module of the monitoring station is programmed using the Arduino platform to interact with the sensors. Arduino's open-source libraries facilitate efficient communication and data processing between the sensors and the river monitoring Station. The program establishes communication with the SIM800 modem, converts sensor readings, and transmits the data to the server via the RS485 converter. Key variables such as APN settings, GPRS credentials, SIM card PIN code, and server address are defined within the Arduino interface, ensuring seamless data transmission and processing. Calibration studies were conducted in both laboratory and field environments to ensure the accuracy and reliability of sensor readings. In the laboratory, the sensor's distance readings were compared with manual measurements, validating the sensor's accuracy and enabling necessary adjustments. The integration of a web interface facilitated real-time monitoring and recording of calibration data, allowing for remote evaluation. Field calibration was performed by installing the station on the Orencik Bridge over the Sakarya River. The sensor's measurements were validated against laser meter and manual measurements, demonstrating high accuracy with minimal error margin. This validation confirmed the sensor's reliability under external environmental conditions. The software infrastructure of the system plays a crucial role in data processing and accessibility [36]. Data collected from the sensors are processed using connections established through the PHP programming language and stored in a database. These data are analyzed and displayed on a web interface, allowing users to easily access real-time information. Measurements are presented with date and time information, and discharge values are calculated in cubic meters per second (m\({}^{3}\)/s), with river depth provided in meters. Additionally, maximum and minimum discharge and river depth values for the last day, week, and month can be viewed in real time. A separate website allows users to view and download data in various formats such as Excel and PDF. The primary objective of the real-time river monitoring station is to detect flood risks early and promptly warn relevant parties. When the water level exceeds a certain threshold, the system automatically sends alerts.