Blackwater -- Cataloging Unit 03010202

• Albemarle-Chowan Accounting Unit 030102
  
• Chowan-Roanoke Subregion 0301
  
• South Atlantic-Gulf Region 03 (There are 198 cataloging units in this region.)
  The state composition by area is 100.0% Virginia.
  

  I. Graphical Locater Maps

  Roads

  Water Only

  8 Digit HUCs

  The area of this HUC in these maps is 1935.3 km² ( 747.5 mi² ) [% in USA = 18.05, % in Region = 20.71]
  The area from the USGS is 744 mi².
  

  II. Flow Connections (upstream and downstream units)

  III. Named places in this watershed (total = 690)

  IV. Elevation Analysis

  This analysis is based on 773500 elevations on a 50 m grid within the area of this HUC.
  The mean elevation is 23.1 m ( 75.8 ft ) [% in USA = 5.40, % in Region = 26.77]
  The elevation standard deviation is 7.8 m ( 25.6 ft ) [% in USA = 3.69, % in Region = 14.14]
  The coefficient of variation is 33.8 %.
  The vertical relief is 46.9 m ( 153.9 ft ) [% in USA = 3.84, % in Region = 16.16]

  Elevation Percentiles

  	0 %	10 %	20 %	30 %	40 %	50 %	60 %	70 %	80 %	90 %	100 %
  meters	0.0	11.4	15.0	18.6	23.0	25.0	28.9	30.0	30.0	30.0	46.9
  feet	0.0	37.4	49.2	61.0	75.5	82.0	94.8	98.4	98.4	98.4	153.9

  

  V. Map Line Analysis

  Note- percentiles are for the feature density, not for the raw total lengths.
  

  line type	km	mi	km/km²	mi/mi²	% in USA	% in Region
  Perennial Shoreline	246.3	153.1	0.127	0.205	64.57	33.33
  Intermittent Shoreline	0.0	0.0	0.000	0.000	26.95	29.80
  Perennial Streams	1073.8	667.3	0.555	0.893	87.54	79.29
  Intermittent Streams	391.5	243.3	0.202	0.326	31.98	46.97
  Canals	0.1	0.0	0.000	0.000	36.62	43.43
  1° roads	30.5	19.0	0.016	0.025	63.67	44.44
  2° roads	170.2	105.8	0.088	0.142	97.58	93.43
  3° roads	107.4	66.8	0.056	0.089	51.40	8.59
  4° roads	2791.5	1734.9	1.442	2.321	74.99	55.05
  Total Roads	3099.6	1926.4	1.602	2.577	75.18	51.52
  Railroads	146.4	91.0	0.076	0.122	76.84	74.24
  Pipes and Powerlines	142.5	88.6	0.074	0.119	86.59	58.59

  
  Of the natural water in this HUC, 22.88% (by length) is intermittent [% in USA = 27.43, % in Region = 44.95]

  VI. Other sites

  • EPA- Surf Your Watershed - Index of Watershed Indicators
  • USGS- Science in Your Watershed - Selected Realtime Streamflow Stations
  • CTIC- Known Your Watershed

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  1999 SEPT 4, Last updated on 2003 JAN 23
  
  D.L. Gustafson, dlg@rapid.msu.montana.edu