Lower Frio -- Cataloging Unit 12110108

• Nueces Accounting Unit 121101
  
• Nueces-Southwestern Texas Coastal Subregion 1211
  
• 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 3087.8 km² ( 1192.7 mi² ) [% in USA = 48.70, % in Region = 43.44]
  The area from the USGS is 1250 mi².
  

  II. Flow Connections (upstream and downstream units)

  III. Named places in this watershed (total = 262)

  IV. Elevation Analysis

  This analysis is based on 1235330 elevations on a 50 m grid within the area of this HUC.
  The mean elevation is 125.6 m ( 412.1 ft ) [% in USA = 17.48, % in Region = 39.34]
  The elevation standard deviation is 37.2 m ( 122.0 ft ) [% in USA = 29.28, % in Region = 41.80]
  The coefficient of variation is 29.6 %.
  The vertical relief is 200.9 m ( 659.1 ft ) [% in USA = 28.90, % in Region = 41.80]

  Elevation Percentiles

  	0 %	10 %	20 %	30 %	40 %	50 %	60 %	70 %	80 %	90 %	100 %
  meters	33.0	78.6	92.1	103.6	111.4	121.4	135.0	146.9	158.0	178.9	233.9
  feet	108.3	257.9	302.2	339.9	365.5	398.3	442.9	481.9	518.4	586.9	767.4

  

  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	380.2	236.3	0.123	0.198	63.48	63.11
  Intermittent Shoreline	9.2	5.7	0.003	0.005	69.78	53.28
  Perennial Streams	129.6	80.5	0.042	0.068	14.97	24.59
  Intermittent Streams	1270.8	789.8	0.412	0.662	59.17	70.49
  Canals	0.0	0.0	0.000	0.000	35.62	41.80
  1° roads	33.2	20.7	0.011	0.017	55.80	58.20
  2° roads	10.4	6.5	0.003	0.005	19.42	7.38
  3° roads	172.3	107.1	0.056	0.090	51.63	71.31
  4° roads	3603.3	2239.5	1.167	1.878	50.64	9.84
  Total Roads	3819.3	2373.7	1.237	1.990	45.90	9.84
  Railroads	28.4	17.7	0.009	0.015	19.90	10.66
  Pipes and Powerlines	44.0	27.4	0.014	0.023	30.18	17.21

  
  Of the natural water in this HUC, 71.52% (by length) is intermittent [% in USA = 71.39, % in Region = 62.30]

  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