BIOL 1500 Lecture Notes - Lecture 3: Urban Stream, Hydrograph, Surface Runoff
24 Dec 2016
School
Department
Course
Professor
Document Summary
(cid:498)streamflow generation(cid:499) =excess water is stored in ocean, lakes, pond, underground. Drainage basin (watershed): the upstream area from which surface water flows towards the channel. Drainage divide: topographic line or boundary separating watersheds. Antecedent conditions: history (cid:523)rainfall moister(cid:524) that"s in the system. Measuring streamflow: velocity (v m/s) area (am2) method. Lag time differences between a forest + an urban stream. Thalwey-> thread of fastest moving h2o with the channel. Cross sectional area of the stream 2m2 -> 2m3/s. 1000l in 1m 3 st. lawrence daily average 1000. Hydrograph shows volume of water through time y-axis is volume m3/s x axis is time (hr) Distance between precipitation and peak is lag time the down (downfall) is hydrograph. Forest stream, losing a lot more water to soil, less than urban stream (effective runoff), fast lag time in urban. More base flow the longer the lag time. Levee is natural levee, occurs after a flood. Streamflow is impacted by landuse in the watershed.
