STREAM (Spatio-Temporal River-basin Eco-hydrology Analysis Model) is a spatially-distributed watershed model designed to scale the capabilities of the CAMEL model (Koo et al., 2005) for application in mid-to-large scale basins. By optimizing grid-to-grid transport algorithms and restructuring river routing mechanisms, STREAM combines the high-resolution spatial heterogeneity of distributed models with the computational efficiency of semi-distributed models. It is specifically engineered to simulate complex watersheds where urban and agricultural landscapes coexist.

• Gangjin Bay Watershed / National Institute of Fisheries Science (2016, 2025)

• Sihwa Lake Watershed / Ministry of Oceans and Fisheries (2011 – 2025)

• Tongyeong and Jaran Bay Watersheds / National Institute of Fisheries Science (2017 – 2019, 2024 – 2025)

• Paldang Lake Watershed / Korea Environmental Industry & Technology Institute (2024 – 2025)

• Gonjiamcheon Watershed / Korea Environmental Industry & Technology Institute (2023 – 2024)

• Geum River Basin / Ministry of Science and ICT (2022 – 2023), KOEM (2018 – 2019), MOF (2014 – 2019)

• Soyang Lake Watershed / Korea Environmental Industry & Technology Institute (2022 – 2023)

• Hansan and Geoje Bay Watersheds / National Institute of Fisheries Science (2021 – 2023)

• Daecheong Lake Watershed / Geum River Basin Environmental Office (2021 – 2022)

• Inbukcheon Watershed / Korea Environmental Industry & Technology Institute (2021)

• Han River Basin / National Institute of Ecology (2020 – 2021)

• Saemangeum Watershed / Rural Research Institute (2013 – 2015), Geum River Basin Environmental Office (2020 – 2021)

• Jaran Bay Watershed / National Institute of Fisheries Science (2017 – 2019)

The STREAM model incorporates specialized modules and algorithms to provide comprehensive watershed analysis:

• Spatial Discretization: Partitioning the watershed into square grids of flexible sizes, where independent mass balance calculations are performed within each cell.

• Vertical Layered Structure: Each grid is vertically structured with a soil layer and a groundwater aquifer to simulate sub-surface interactions.

• Dynamic Time-Stepping: Internal calculation of the simulation time interval based on river reach lengths to optimize numerical stability.

• Computational Optimization: Elimination of grid-to-grid lateral mass transport to significantly enhance simulation speed for large-scale watersheds.

• Hydraulic Flow Control: Explicit control of surface runoff based on the height of agricultural levees (paddy/field dikes) and river embankments.

• Hydraulic Infrastructure Modeling: Automated internal generation of hydraulic structures, including weirs, reservoirs, sluice gates, and irrigation channels, based on user-defined specifications.

• Nutrient Cycling and Transport: Simulation of the transformation and transport processes of Carbon (C), Nitrogen (N), and Phosphorus (P) within soil and surface water systems.

• Multi-Class Sediment Transport: Classification of sediment by particle size (clay, silt, fine sand, coarse sand) and transport mode (suspended load and bed load).

• Agricultural Hydrology: Detailed simulation of irrigation requirements and drainage runoff through complex agricultural water supply systems.

• Urban Stormwater Management: Modeling of Combined Sewer Overflows (CSOs) and Sanitary Sewer Overflows (SSOs) within urbanized catchments.

• NPS Mitigation Strategies: Specialized modules for simulating road sweeping operations (vacuum and water cleaning) and various Non-Point Source (NPS) reduction facilities, such as constructed wetlands and infiltration basins