HYDROLOGIC CHARACTERISTICS OF AN AGRICULTURAL WATERSHED IN RURAL QUEBEC

The hydrology of a 26.1 km(2) rural Quebec watershed was investigated. Thirty-one rainfall-runoff events were used in the analysis. The aver age time of concentration (t(c)), lag time (t(l)) and time to peak (t( p)) for these events were measured as 7.4, 8.5, and 13.1 h, respective ly. The U.S. Soil Conservation Service and Airport equations provided the best estimates of t(c) (6.1 and 5.9 h, respectively), though all e quations underestimated t(c). Lag time and t(p) were variable and rela ted to storm duration. Equations describing relationships between peak discharge, antecedent flow, total rainfall, and surface runoff were d eveloped. Surface runoff was also correlated to event rainfall and the 14-day antecedent precipitation index. All rainfall-runoff relationsh ips demonstrated strong correlation. Peak and antecedent flow appeared to be correlated to the 30-minute maximum rainfall intensity. These a ttributes characterize rural watersheds and provide the basis for mode lling their hydrological responses.