stream : body of running water that is confined to a channel and moves downhill due to gravity
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StreamStream: body of running water that is confined to a channelchannel and moves downhill due to gravity
Drainage BasinDrainage Basin: total area drained by a stream. Larger streams have larger drainage basins.
The size and composition of the sediment carried by the stream The size and composition of the sediment carried by the stream depends on the nature of the drainage basin.depends on the nature of the drainage basin.
Contour Lines:
One last thing about contour lines is that they “V” upstream when they cross a river drainage. Blue represents water features on topographic maps, and the line and three dot pattern of the streams on this map indicate an intermittent stream – sometimes it flows and sometimes it doesn’t. (*)
Next, notice how the contour lines form a “V” and that the “V” points towards the top of Squaw Peak (higher elevation), The rule of thumb is that the “V’s” point upstream,(*)
What was done was to draw a line that connects the tips of the “V”s.
In this illustration of North Mountain Park all the stream drainages will be highlighted in purple. It includes the blue stream lines as well as the unmarked drainage.
Fig. 10.27
Flood Plain:Flood Plain: area habitually flooded by a stream at high water. Contains fine-grain sediment deposited during flooding
Natural levee:Natural levee: low ridges formed along sides of main stream channel during flooding.
Base Level
• Base level ‑ the lower limit to which streams can erode.
• Sea level is the ultimate base level.
• Local or temporary base level: a lake or another stream that an upland stream flows into. Could also be a waterfall.
Stream Valleys
• Stream valleys‑form and evolve from stream erosion. • Small, steep walled, deep valleys: gullies. • Large, steep walled, steep sided valleys: canyons.
DischargeDischarge
Vwater velocity
(m/sec)
Q = W
average width (m)
Daverage
depth (m)
Volume of water per unit time that passes a specific point on the river.
m3/s
WaterWatchWaterWatch
This is from a rain gauge at the Reedy River downstream of downtown Greenville..
http://waterdata.usgs.gov/
0.1 in of 0.1 in of rainrain
1.2 in of 1.2 in of rainrain
WaterWatchWaterWatch
This is from a gauge on the Reedy River downstream of downtown Greenville. Note the rapid peak and relatively rapid decline.
http://waterdata.usgs.gov/
Big stormBig storm
Rapid responseRapid response
Why?Why?
WaterWatchWaterWatch
This is from a gauge in a rural area. Note the slow peak and decline.
http://waterdata.usgs.gov/
Big stormBig storm
Slow responseSlow response
Why?Why?
WaterWatchWaterWatch
This is from a gauge from below one of the dams on the Catawba River. The weird pattern is caused by controlling outflow from a hydroelectric dam.
http://waterdata.usgs.gov/
Big stormBig storm
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