APPENDIX H
Spatial Analysis of Vernon Subwatershed
Reach III ) Red River Basin
Wilbarger County, Texas
BASIN SUMMARY REPORT
FOR THE
RED RIVER BASIN
September 1999
1.0 Background
Reach III of the Red River Basin is being monitored by the Red River Authority of Texas during FY 1999. At the beginning of this period, it became necessary to choose a priority subwatershed to conduct further study of concerns identified during previous assessments. The staff of the TNRCC delineated the entire Red River Basin, and the subwatersheds for Reach III were analyzed to determine which area should be selected. The population density and the density of the major points of interest were the primary factors in selecting the priority subwatershed for this reach. As a result, the area surrounding the City of Vernon in Wilbarger County was selected as the priority subwatershed for this special study.
The main surface features of the subwatershed selected include a small section of the Pease River and approximately one third of the City of Vernon. This section of the Pease River is fed by a large system of tributaries, including the North, Middle, and South Forks of the Pease River. This subwatershed contains a large number of groundwater wells which are used for municipal and irrigation purposes and also contains a large number of petroleum storage tanks (PST). The urban and rural areas within this subwatershed depend solely upon groundwater due to the high concentrations of dissolved solids in all surface water sources available.
The economy of this study area is supported by agri-business, farming, ranching, petroleum production and light industry, all of which pose potential stormwater runoff problems. This subwatershed contains one monitoring station with sufficient data. The data were adequate to provide significant statistical and spatial analyses.
2.0 Identifying Sources
Global positioning (GPS) data were collected on petroleum storage tanks (PSTs) and groundwater wells to obtain accurate locations on potential sources of pollution. Maps were then prepared depicting the location of these potential sources that might have the greatest influence on the receiving waters within this subwatershed.
3.0 Events and Issues
Events and issues identified in this subwatershed are as follows:
June 8, 1991 ) Significant Rainfall Event
August 2, 1995 ) Significant Rainfall Event
January 31, 1997 ) Vernon Wastewater Treatment Plant Permit Amendment
4.0 Statistical Analysis
Statistical analysis of chemical constituents found to be a concern was performed on station number 10165 located in the selected subwatershed.
|
Station |
Parameter |
N |
Mean |
SD |
Max |
Min |
N* |
Criteria |
|
10165 |
00620 |
39 |
0.29 |
1.023 |
6.4 |
< 0.01 |
1 |
1.0 |
|
10165 |
00650 |
15 |
0.38 |
0.5152 |
1.77 |
< 0.03 |
7 |
0.2 |
|
10165 |
00660 |
15 |
0.07 |
0.0923 |
0.4 |
< 0.03 |
1 |
0.1 |
|
10165 |
00665 |
56 |
0.15 |
0.238 |
1.0 |
< 0.01 |
9 |
0.2 |
|
10165 |
00671 |
53 |
0.06 |
0.183 |
1.0 |
< 0.01 |
2 |
0.2 |
|
10165 |
31616 |
47 |
324.11 |
1,466.365 |
10,000 |
< 1.0 |
5 |
200 |
5.0 Trend Analysis
Trend analysis of chemical constituents found to be a concern or possible concern in the 1996 screening process was performed on station number 10165 located in the selected subwatershed. There were six constituents with sufficient data analyzed and no significant trends were found.
|
Station |
# Events |
Date Range |
Determination |
|
10165 |
80 |
10/28/1981 ) 12/16/1998 |
Sufficient Data |
|
Parameters |
N |
p-value |
|
00620 |
39 |
0.010077 |
|
00650 |
15 |
0.321149 |
|
00660 |
15 |
0.451974 |
|
00665 |
56 |
0.684619 |
|
00671 |
53 |
0.426954 |
|
31616 |
47 |
0.489080 |
Map of Vernon Subwatershed (Transportation Theme)
Map of Vernon Subwatershed (City Boundary Theme)
Map of Vernon Subwatershed (Hydrology Theme)
Map of Vernon Subwatershed (Water Resources I)
Map of Vernon Subwatershed (TNRCC Monitoring Stations Theme)
Map of Vernon Subwatershed ( Miscellaneous Theme)
