LARGE AREA HYDROLOGIC MODELING AND ASSESSMENT PART II: MODEL APPLICATION¹

TLDR

The study applies a river basin–scale hydrologic model to the Richland and Chambers Creeks watershed in Texas. The model was driven by GIS‑derived hydrographic and geographic data, calibrated with 12‑station weather records (1965–1984) and 1994 sediment survey data, and validated on the Mill Creek subwatershed. The model explained 84 % of calibration and 65 % of validation stream‑flow variability and predicted sediment loads within 2 % and 9 % of observed values for the RC and Mill Creek watersheds.

Abstract

ABSTRACT: This paper describes the application of a river basin scale hydrologic model (described in Part I) to Richland and Chambers Creeks watershed (RC watershed) in upper Trinity River basin in Texas. The inputs to the model were accumulated from hydro‐graphic and geographic databases and maps using a raster‐based GIS. Available weather data from 12 weather stations in and around the watershed and stream flow data from two USGS stream gauge station for the period 1965 to 1984 were used in the flow calibration and validation. Sediment calibration was carried out for the period 1988 through 1994 using the 1994 sediment survey data from the Richland‐Chambers lake. Sediment validation was conducted on a subwatershed (Mill Creek watershed) situated on Chambers Creek of the RC watershed. The model was evaluated by well established statistical and visual methods and was found to explain at least 84 percent and 65 percent of the variability in the observed stream flow data for the calibration and validation periods, respectively. In addition, the model predicted the accumulated sediment load within 2 percent and 9 percent from the observed data for the RC watershed and Mill Creek watershed, respectively.