Author(s): Hosoo Lee; Gwangmin Ok; Yeonghwa Gwon; Dongsu Kim; Young Do Kim
Linked Author(s): Dongsu Kim, Yeonghwa Gwon, Young C. Kim, YongDo Kim
Keywords: Spectral data Sewer pipes Stormwater pipes Water depth Non-contact OBRA Monitoring chamber
Abstract: This study aims to develop flow monitoring technology for urban flood defense in sewer and stormwater drainage systems. As urban flooding damage increases due to rapid climate change and intense rainfall, the importance of monitoring existing sewer and stormwater drainage systems is becoming more critical. Traditional measurement methods based on water level-discharge relationship curves through water level gauges suffer from reduced accuracy due to sediment accumulation and variations in internal pipe flow, which limits the performance evaluation of flood defense infrastructure. To overcome these limitations, this study proposes a contactless monitoring approach that measures depth rather than water level within sewer pipes by utilizing spectral data. A method to measure the depth in sewer and stormwater pipes using the OBRA technique with multispectral sensors was developed. Experiments were conducted under various light source and illumination conditions using a monitoring chamber to ensure accurate data collection and analysis. Additionally, an algorithm was implemented using Python's OpenCV library to correct positional errors that may occur during multispectral image analysis, enhancing measurement accuracy. The disparity correction using tracking points minimized discrepancies between images, enabling the collection of reliable data. Furthermore, based on experimental results, the effects of light source types and illumination changes on depth measurements were analyzed. Subsequently, the study evaluated the accuracy of the proposed depth measurement approach by comparing and analyzing flow estimation methods based on depth assessment using spectral data against supply flow data. This study presents a novel methodology to address the limitations of existing sewer and stormwater monitoring technologies and is expected to contribute to the enhancement of real-time monitoring technology in urban flood response systems.
Year: 2025