GENERAL GEOLOGY

Detailed explanation-1: -Human activities can affect runoff In addition to increasing imperviousness, removal of vegetation and soil, grading the land surface, and constructing drainage networks increase runoff volumes and shorten runoff time into streams from rainfall and snowmelt.

Detailed explanation-2: -Temperature, wind speed and humidity affect evaporation and transpiration rates, thus soil moisture regime and infiltration rate, and finally runoff volume.

Detailed explanation-3: -Runoff volumes are affected by various factors: type of precipitation, duration, amount, and intensity of precipitation. In addition, the type of watershed also influences the amount of runoff.

Detailed explanation-4: -Runoff from nonpoint sources includes lawn fertilizer, car exhaust, and even spilled gasoline from a car. Farms are a huge nonpoint source of runoff, as rainwater and irrigation drain fertilizers and pesticides into bodies of water. Impervious surfaces, or surfaces that can’t absorb water, increase runoff.