To:††††† Interested Parties
From:††††† Environmental Services division
This is the Sabine River Authority Water Quality Summary for December 2001. Water quality sampling was performed December 11 through December 12. Total organic carbon and Nitrate & Nitrite werenít run this month due to equipment failure.† Recent weather was cool to mild and with normal rainfall in the Upper Basin and above normal rainfall in the Lower Basin.† The Upper Basin received 2.47 Ė 4.29 inches of rainfall during the 28 days since the previous sample run as recorded at Lake Tawakoni and Lake Fork respectively.† Toledo Bend and Orange received 8.75 and 13.41 inches respectively during the 28 days preceding the sample run.† At the Toledo Bend weather station, 6.72 inches of rain fell from 11/27 to 11/29/01.† The Orange station reported 10.75 inches from 11/27 to 11/28/01.† This rain event occurred 18-20 days prior to the Lower Basin sample run.† Air temperatures during the most recent three days prior to the sample run were cooler and in the 50ís and 60ís. Highs prior to the cooler weather were mostly in the 70ís throughout the Basin.† Recent nighttime lows were in the 20ís and 30ís in the Upper Basin and Toledo Bend, and in the 40ís in the Orange area.† Only the deepest sites were weakly stratified with respect to dissolved oxygen: LT23A at Lake Tawakoni and TB6K at Toledo Bend Reservoir.
Upper Sabine Basin Above Toledo Bend Including Lake Fork and Lake Tawakoni
For the December sample run, most of the parameterís values seen at the Upper Basin sites were consistent with water of high quality. A rain event during the night prior to and during the second day of the sample run caused high turbidity and E. coli values at most sites sampled on 12/12/01. Bacteriological counts were above stream standards at SR15, SR14, SR11, and SR10.† Notice that turbidity is also markedly higher and secchi visibility is shallower at these sites.† Lake Fork Reservoir was mixed at all sites and Lake Tawakoni was mixed at all sites except LT23A, which was weakly stratified at the deepest depth.
Lower Sabine Basin Including Toledo Bend to Morgan Bluff
The December monthly sampling results were indicative of water of high quality at most sites.† Toledo Bend Reservoir was still below pool level at the time samples were taken, but the levels were on the rise.† The reservoir was just above 165 feet.† Slight thermal stratification of the water profile was exhibited at most stations.† Oxygen levels were very similar throughout the water column at most sites.† E. coli results that were above stream standards were found at stations TB8, TB6M, TB6L, TB6N, and SR5.† These stations also received significant rainfall just before or during the time they were sampled.† Runoff from these rains could help explain the high bacterial results.† Stations TB6A and TB6S were not sampled this month. These stations were inaccessible due to weather conditions.
Tidal Section of the Sabine Basin below Morgan Bluff
Stations sampled in the tidal portion of the Sabine Basin had values that were consistent with water of high quality at most sites.† Station SRT1 was the only site that showed any salinity gradient.† The only surface salinity reading was recorded at station BB1, with a value of 3 ppt. Station SRT1 recorded the only other salinity reading of 2 ppt at a depth of 7.3 meters.† Stations SRT2 and SR1 recorded pH values below stream standards.†† E. coli results at station SR1 and Enterococcus results at stations ICW1, BB1, SRT2, and SRT1 were all found to be above the stream standard.† Runoff from rainfall that occurred less than twenty-four hours prior to sampling could have attributed to these values.
This Report and additional data for these monitoring stations are available on our World Wide Web site (www.sra.dst.tx.us). If you have any questions or comments concerning this report, please contact:
ō Upper Sabine Basin
John Payne, Upper Basin Field Office Coordinator
ō Lower and Tidal Sabine Basin
Jerry Wiegreffe, Lower Basin Field Office Coordinator
If above are unavailable
Miles Hall, Assistant Division Manager Environmental Services
Printed Monday, February 11, 2002