Conservation Service Curve Number Approach Research Articles

Estimating urban flooding potential near the outlet of an arid catchment in Saudi Arabia

ABSTRACTThe aim of this study is to build a flood simulation model for the city of Hafr Al-Batin catchment area. The model consists of a hydrologic model, a hydraulic model and pre- and post-processing tools. A geographic information system-based modelling interface was used to pre-process the terrain and rainfall data and generate input files for hydrologic and hydraulic models. Soil map data, land cover map, land use map and digital elevation model was used to delineate the physical watershed's characteristics. The runoff estimation was based on the widely known Soil Conservation Service curve number approach. The hydrologic/hydraulic model simulations simulated the runoff hydrograph corresponding to different design storms and helped to delineate the resulting flood inundation maps. The results indicate good agreement between the delineated inundation map and the hazard map developed by the municipality. They also show that the location of the city complicates the runoff response for small storms creating two distinct peaks. The results of this study can be utilized for planning purposes and in the design of flood control structures as the study has estimated the runoff corresponding to different design storms and used hydraulics and geospatial data in delineating the flood zones.

Use of remotely sensed data to estimate the flow of water to a playa lake

The presence of water on Rosamond lake presents potential operational hazards and environmental issues for Edwards Air Force Base (EAFB). This research tests the utility of threshold precipitation in predicting inundation of Rosamond lake. Arcview v.3.2, with the ESRI extension ‘watershed delineator’ and detailed field investigations were used to delineate the watershed and determine elevation-bounded intervals based on soil types and vegetation types and densities. The natural resource conservation service curve number approach was used to estimate the initial abstraction of precipitation, infiltration, runoff, and estimate the threshold depth of precipitation. Climatic data from the western regional climate center and remotely sensed data from the USA Army Corps of Engineers Cold Regions Research and Engineering Laboratory were used to examine the association between winter precipitation events and surface water inundation. Visual_Data, a remote sensing analysis program, was used to analyze the Landsat multispectral images in the infrared (IR) bands and apply remote sensing techniques to determine the areal change of water on Rosamond lake over a defined temporal resolution. Threshold precipitation was then compared to precipitation events that occurred within the temporal resolution of the image subtractions to determine the association between precipitation and the inundation of Rosamond lake. The results of this study demonstrated that with refinement this approach could be used to predict the flow of water to a playa lake to predict the duration of inundation.