Jaewan Yoon

Application of GIS Technologies in Port Facilities and Operations Management

Prepared by the Ports and Harbors Committee of the Coasts, Oceans, Ports, and Rivers Institute of ASCE.

Brine Discharge Load Design and Optimization Framework for Desalination Process Using Mixing Plume Criteria and Discharge Pipe Length Augmentation

The operation of the desalination plants leads to a continuous step loading of the brine, typically in a double salinity mass concentration of the ambient receiving water. Currently there is no federal or state regulations in the United States except the state of California or no worldwide standard that regulate brine discharge and resultant brine dilution condition. In this study, the 10% rule regulated under the California Salinity Control was applied to the sourcesink design process for optimizing brine outlet conveyance and release configuration. Objectives of the proposed the source-sink design process are to keep the ambient coastal environment protected from excessive salinity spikes triggered by the brine discharge and to optimize the outlet conveyance dimensions and release configuration subjected to the implementation cost. Reflecting these two objectives simultaneously, a risk analysis was incorporated to solve a constrained minimization optimization problem, and Monte Carlo simulation technique was formulated based on the analysis results from Huntington Beach, California on the maximum allowable time of exposure to the high salinity. The brine plume dispersion and spatiotemporal dilution were correspondingly simulated using advection-diffusion equation on sloping seabed. As a result, the outlet length was optimized to minimize the excessive salinity spikes compliant to 10% rule regulated under the California Salinity Control. The methodology has been applied to five different case studies around world where each site has very diverse mixing characteristics. In addition, a nomograph has been developed to relate the outlet conveyance length as a function of mixing and dilution characteristic of the study area. The results indicate that the risk analysis in some cases can decrease the outlet conveyance length up to 100%.

Development of Spatiotemporal Source-Sink, Stratified Nitrogen Water Quality Model

A spatiotemporal source-sink, stratified water quality model was addressed in this paper. Model development effort was underway by coupling a surface water quality model with a hydrologic model. The hydrologic model, which estimated stormwater runoff from surrounding basins using Soil Conservation Service (SCS) method, was integrated with CREAMS nutrient submodel to evaluate corresponding sedimentary nitrogen transported from the basins. Afterwards a two-layer finite segment framework was developed to characterize in-reservoir water quality conditions. This framework predicted the fate and transport of Nitrogen influx in the reservoir. Verification of the water quality model was achieved through in-situ data from two sampling locations in the reservoir. A Geographic Information System (GIS) was used extensively in watershed analysis such as utilizing Digital Elevation Model (DEM) and raster data operations to delineate watersheds, and then to parameterize spatiotemporal topographic features for estimating stormwater runoff and nitrogen loadings.

Heuristic Knowledge-based Tool for Rainfall Synthesis, Runoff Estimation and Hydrograph Generation

Knowledge-based engineering has emerged as a potential technique for incorporating human expertise and some degree of intelligent judgment into decision-supporting procedures. A knowledge-based expert system (KBES) methodology to estimate the volume and hydrograph of direct surface runoff from rain events using the Soil Conservation Service Runoff Curve Number method was developed for hydrologic modeling and decision support systems. The KBES approach was designed to determine runoff curve numbers with limited available information on watershed characteristics, to generate rainfall intensity of the geographic location for desired durations and return periods, and to use the curve number and rainfall intensity estimates to calculate runoff volume, peak runoff and time-to-peak for design purposes. Rainfall intensity estimation is based on four regional partial-duration series parameters corresponding to a given geographic location. Currently, a regional parameter database for 12 midwestern states (Illinois, Indiana, Iowa, Kansas, Michigan, Minnesota, Missouri, Nebraska, North Dakota, Ohio, South Dakota, and Wisconsin) is compiled into the KBES for the rainfall synthesis.