Sabine River Authority of Texas

To: Interested Parties

From: Environmental Services division

RE: january 2000 Water Quality Monitoring Report

This is the Sabine River Authority Water Quality Summary for January 2000. Water quality sampling was performed January 11 through January 13. Daytime high air temperatures during the seven days prior to the sampling dates were mostly in the 50ís and 60ís in the Upper Basin and in the 60ís and 70ís in the Lower Basin. Nighttime lows in the mid 20ís were recorded several nights in the Upper Basin but most were in the 30ís and 40ís. Low temperatures in the Lower Basin were mostly in the 40ís and 50ís. About an inch of rainfall was recorded in January prior to the sample run.

Upper Sabine Basin Above Toledo Bend Including Lake Fork and Lake Tawakoni

For the January sample run, most of the water quality values seen at the Upper Basin sites were consistent with water of high quality. The most recent rainfall was a 0.6 inch rain three days prior to sampling. Lake Tawakoni recorded 0.69 inches of rain since January 1st (11 days previous) and Lake Fork recorded 0.63 inches during the same period. Water temperature and dissolved oxygen profiles were similar from surface to bottom at Lake Tawakoni and Lake Fork indicating complete mixing, with no significant thermal stratification. Elevated dissolved oxygen at several reservoir sites indicate high algal activity and field notes indicate water color is somewhat greener than usual for winter months. This may be partially due to mild temperatures seen so far this winter. Water quality parameters were within stream standards at all Upper Basin reservoir sites and ammonia was slightly over screening criteria at SR10.

Lower Sabine Basin Including Toledo Bend to Morgan Bluff

Samples taken during the January 2000 WQM sampling were indicative of high quality water at most sites. At the time of sampling, Toledo Bend Reservoir was still exhibiting low water level conditions. Water sampled at most sites on the reservoir was very clear and green. Deep-water stations of the reservoir were well mixed, having no thermal stratification. Station TB6N, located below a municipal wastewater treatment plant, had higher conductivity, chloride, phosphate, and ammonia results. Station TB6N also had very low dissolved oxygen concentrations compared to other sites and was covered with duckweed at the time of sampling. Station BA4, located below a paper mill, had higher conductivity, chloride, sulfate, and fecal coliform results. Water in the bayou was very black and low at the time of sampling. Samples taken from Station SR3, located downstream of BA4, exhibited the same black color as the water in Anacoco Bayou.

Tidal Section of the Sabine Basin below Morgan Bluff

Water samples indicative of high quality were collected from the tidal portion of the Sabine Basin. All surface water values measured were within stream standards criteria. A definite salt-water wedge was detected as far north as the I10 Bridge. Salinity readings ranged from <1.0 ppt at surface to 16 ppt at a depth of 9.8 meters. No tidal action was observed at the time of sampling. Deep-water profiles were well mixed and exhibited no thermal stratification.

This Report and additional data for these monitoring stations are available on our World Wide Web site ( If you have any questions or comments concerning this report, please contact:


Printed Wednesday, July 19, 2000