Development of a base model for flood forecasting studies in the Humber River Basin (NL) and selection of an appropriate model forcing dataset

• Main Author: Jasim, Faten
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2014
• Subjects: Canada; Newfoundland
• Online Access: https://research.library.mun.ca/6332/; https://research.library.mun.ca/6332/1/Thesis_Faten_Jasim_Final.pdf; https://research.library.mun.ca/6332/3/Thesis_Faten_Jasim_Final.pdf

The Humber River basin (7860 km²) in Newfoundland is the second largest watershed on the island portion of the province. Efforts are underway to establish a base model for a flow forecasting system within the basin for flood damage mitigation and hydroelectric power optimization. This study examines three model forcing datasets (temperature and precipitation) and attempts to identify the best option based on the simulated streamflow amounts. In past stochastic studies, difficulty has been encountered due to a lack of observed data and the complexity of the hydrologic system, especially during the snowmelt period. Strong topographic influences within the basin limit the representativeness of observations. Given the strong topographic influences on orographic precipitation and temperature, the WATFLOOD gridded hydrologic model was selected, which permits the use of topographically adjusted gridded meteorological inputs as well as station data. Adjusted station data from APC2 (Second Generation Adjusted Precipitation for Canada), NARR (North American Regional Reanalysis) and CaPA (Canadian Precipitation Analysis) were used in the study. Based on 30-year run sequences, a base model able to translate weather and antecedent moisture to streamflow has been developed. Generation of initial conditions for forecasting purposes cannot rely on APC2 data due to its production lag. Instead, the NARR and CaPA products were evaluated against gridded station observations. Results indicated that APC2 produces the best results in terms of streamflow followed by NARR and CaPA. For model initialization purposes, the NARR precipitation dataset is recommended over CaPA for the Humber River.