■  Urban Drainage System Management

Recent climate changes increased the likelihood of heavy rainfall in urban area in Korea, which can cause devastating property damage and loss of life. The importance of urban inundation prevention will also increase. In order to mitigate the impact of urban inundation on the system, structural solutions such as improvement of efficiency in hydraulic structure, making urban drainage plan and increasing the size of sewer conduits has been adopted in the urban drainage system. However, structural solutions are not a cost-effective alternative. Furthermore, most urban cities are lack of space for new hydraulic structure to capture the run-off in a developed area (e.g., constructing a detention basin). High-level technology such as optimal operation of combined drainage systems among non-structural solutions in urban area is not sufficient for overcoming these drawbacks.

Hydro systems laboratory has researched about urban drainage system management in two projects: ‘Development of Advanced Techniques in Combined Inland-River Systems for Reducing Urban Inundation’ supported by the Ministry of Public Safety and Security and ‘Development of GIS based Pump Station Operation with Decision Support System’ supported by Small and Medium Business Administration.

■ Related Research Project 

  (Development of Advanced Techniques in Combined Inland-River Systems for Reducing Urban Inundation)

The main objective of the project is to develop an intelligent real-time operation tool for urban drainage system consisting of pump stations, detention reservoirs and sewer networks that minimizes the flood risk and inundation areas in combined inland and river systems considering the flood characteristics. To achieve this target, the contents of the research are divided to four main parts including as follows:

 ·         

● Development of optimization techniques for reducing urban inundation

● Development and analysis of pumping systems in combined inland-river system

● Development of uncertainty analysis and risk assessment of combined inland-river system

● Verification of the proposed operations and developing the monitoring system

The detail research topics of each year are as flows:

● 1st year: 

→ Making contents of optimized and combined inland-river systems

● 2nd year:

→ Development of estimating the extent of reduced urban inundation by operating combined 

    inland-river system

→ Development of optimal operating technique for reducing urban inundation through decreasing 

   downstream elevation in river considering elevation change

● 3rd year:

→ Analysis of reducing urban inundation impact by optimal operating

● 4th year: 

→ Development of proto-type for optimal operating system

● 5th year: 

→ Making practical manuals for combined inland-river optimal operating system

■ Related Research Project 

  (Development of GIS based Pump Station Operation with Decision Support System) 

In general cases, pump operation is solely based on the water level in the detention pond at the outlet. Pump station operator manually turn on and off the pumps. We developed a new pump operation approach in which pumps are operated based on the outflow computed from an urban drainage analysis program (EPA-SWMM) given real-time rainfall measurement.

In this project, based on FFC6 (Free Flood City 6), which is developed under the project ‘Urban Flood Prevention Plans and Management’ by the Ministry of Land, Infrastructure and Transport, Urban Flood Disaster Management Technology Research Group (2003~2008) connection with forecast data of the Meteorological Administration, reflects field conditions as much as possible and develop GIS-based decision support system for operating pump station optimally.

The contents of the research are divided to four main parts including as follows:

- Expansion of prediction time through connection with forecast data of the Meteorological Administration: Utilizing the forecast with actual levels of rainfall up to this point to improve the prediction accuracy of inflow and extend the forecast period.

- Operating pump station based on real-time field measurements: Development of decision support system considering the experience and improvements of the site operator with a long operational experience.

- Algorithm development for the optimum operation of pump station: Algorithm for performing optimum pump operation depending on field conditions such as drainage basin area, reservoir and pumping capacity, etc.

- Systematic management system in accordance with the distortion and deterioration of the pipe: Systems that uses GIS to manage the embedded and property information of the upstream sewer and utilizing relevant information at the pump station.

■ Research Achievements

● FFC6 (Free Flood City 6)

)

- Developed for ‘Urban Flood Prevention Plans and Management’ by the Ministry of Land, Infrastructure and Transport, Urban Flood Disaster Management Technology Research Group (2003~2008)

- Pump station is one of the most active and reliable way to protect against flooding caused by the overflowing in the low-lying areas of the city. But flooding has been repeated due to insufficient management standard, operations depending on the experience of the manager and neglects the management, etc. Therefore, the system reduces flooding low-lying areas of the city, and operates pump station through totally, considering upstream distribution network for efficient and reliable flood prevention activities; Real-time pump station operation system.

- From 2009 to 2011, it was installed at 9 pump stations of Seoul (Gasan 1, Yongdu, Yongdap, Singil, Ohgeum, Guro 1, Seongsan, Sillim, Joongdong) and has been operating since.

● G-PUMPS (GIS based Predicting Urban-inundation and Managing Pump System)

)

- Developed for ‘GIS based Pump Station Operation with Decision Support System’ by Small & Medium Business Administration (2014~2015)

- Development of field customized practical system for complete conjunction with pump control system of the existing system through maximization of pump stations’ field applicability.

- Pump stations operating decision support system through providing drainage status and pipe network information based on GIS.