Toyah -- Cataloging Unit 13070003

• Lower Pecos Subregion 1307
  
• Rio Grande Region 13 (There are 70 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 2586.1 km² ( 998.9 mi² ) [% in USA = 36.29, % in Region = 25.71]
  The area from the USGS is 1030 mi².
  

  II. Flow Connections (upstream and downstream units)

  III. Named places in this watershed (total = 356)

  IV. Elevation Analysis

  This analysis is based on 1032874 elevations on a 50 m grid within the area of this HUC.
  The mean elevation is 1140.6 m ( 3742.1 ft ) [% in USA = 75.23, % in Region = 34.29]
  The elevation standard deviation is 353.8 m ( 1160.7 ft ) [% in USA = 87.83, % in Region = 81.43]
  The coefficient of variation is 31.0 %.
  The vertical relief is 1588.5 m ( 5211.6 ft ) [% in USA = 78.54, % in Region = 62.86]

  Elevation Percentiles

  	0 %	10 %	20 %	30 %	40 %	50 %	60 %	70 %	80 %	90 %	100 %
  meters	769.0	808.8	856.0	893.9	939.5	1004.9	1088.0	1193.5	1467.3	1778.8	2357.5
  feet	2522.9	2653.5	2808.4	2932.7	3082.3	3296.9	3569.5	3915.6	4813.9	5835.9	7734.5

  

  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	22.6	14.0	0.009	0.014	11.27	62.86
  Intermittent Shoreline	9.2	5.7	0.004	0.006	72.52	40.00
  Perennial Streams	9.1	5.6	0.004	0.006	4.83	31.43
  Intermittent Streams	1018.9	633.2	0.394	0.634	57.37	44.29
  Canals	55.4	34.4	0.021	0.034	74.04	75.71
  1° roads	44.4	27.6	0.017	0.028	65.85	85.71
  2° roads	43.3	26.9	0.017	0.027	37.57	55.71
  3° roads	69.8	43.4	0.027	0.043	27.81	58.57
  4° roads	2194.1	1363.6	0.848	1.365	25.39	48.57
  Total Roads	2351.6	1461.5	0.909	1.463	25.20	50.00
  Railroads	39.2	24.4	0.015	0.024	24.92	57.14
  Pipes and Powerlines	0.0	0.0	0.000	0.000	8.67	24.29

  
  Of the natural water in this HUC, 97.02% (by length) is intermittent [% in USA = 94.84, % in Region = 60.00]

  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