San Saba -- Cataloging Unit 12090109

• Middle Colorado-Concho Accounting Unit 120901
  
• Lower Colorado-San Bernard Coastal Subregion 1209
  
• Texas-Gulf Region 12 (There are 122 cataloging units in this region.)
  The state composition by area is 100.0% Texas.
  

  I. Graphical Locater Maps

  Roads

  Water Only

  8 Digit HUCs

  The area of this HUC in these maps is 6078.0 km² ( 2347.7 mi² ) [% in USA = 87.07, % in Region = 81.97]
  The area from the USGS is 2330 mi².
  

  II. Flow Connections (upstream and downstream units)

  III. Named places in this watershed (total = 613)

  IV. Elevation Analysis

  This analysis is based on 2427902 elevations on a 50 m grid within the area of this HUC.
  The mean elevation is 601.2 m ( 1972.4 ft ) [% in USA = 60.92, % in Region = 83.61]
  The elevation standard deviation is 107.2 m ( 351.7 ft ) [% in USA = 57.37, % in Region = 88.52]
  The coefficient of variation is 17.8 %.
  The vertical relief is 425.4 m ( 1395.7 ft ) [% in USA = 49.83, % in Region = 81.97]

  Elevation Percentiles

  	0 %	10 %	20 %	30 %	40 %	50 %	60 %	70 %	80 %	90 %	100 %
  meters	339.0	438.8	487.0	543.3	579.4	626.9	663.7	687.4	701.0	728.7	764.4
  feet	1112.2	1439.6	1597.7	1782.5	1900.9	2056.7	2177.5	2255.2	2299.8	2390.7	2507.8

  

  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	103.6	64.4	0.017	0.027	17.62	14.75
  Intermittent Shoreline	18.3	11.4	0.003	0.005	70.06	54.10
  Perennial Streams	371.0	230.6	0.061	0.098	19.04	35.25
  Intermittent Streams	2839.9	1765.0	0.467	0.752	65.56	84.43
  Canals	14.1	8.8	0.002	0.004	51.87	67.21
  1° roads	1.0	0.6	0.000	0.000	35.20	18.03
  2° roads	238.5	148.2	0.039	0.063	69.87	63.11
  3° roads	84.8	52.7	0.014	0.022	15.11	15.57
  4° roads	7760.7	4823.3	1.277	2.054	62.25	21.31
  Total Roads	8084.9	5024.8	1.330	2.140	54.29	18.03
  Railroads	85.6	53.2	0.014	0.023	23.87	15.57
  Pipes and Powerlines	85.0	52.8	0.014	0.023	29.70	16.39

  
  Of the natural water in this HUC, 85.76% (by length) is intermittent [% in USA = 84.46, % in Region = 88.52]

  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