To: Interested Parties
From: Environmental Services division
This is the Sabine River Authority Water Quality Report for November 2002. Water quality sampling was performed November 12th through November 14th. Recent weather in the Basin was variable with daytime high air temperatures from the 60s to the 80s at Lake Tawakoni and Lake Fork, and ranging from 60s to the 80s at Toledo Bend Reservoir and Orange. Lows were mostly in the 30s and 40s at Lake Tawakoni, 40s through 60s at Lake Fork, 30s through 60s at Toledo Bend, and 40s through 60s in Orange. The Upper Basin received 6.40 – 5.99 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 had unusually high amounts of rainfall recording 18.74 and 18.54 inches respectively during the 28 days preceding the sample run. Reservoir profiles indicated complete mixing of the water column in Lake Tawakoni, Lake Fork and Toledo Bend reservoirs.
Upper Sabine Basin Above Toledo Bend Including Lake Fork and Lake Tawakoni
For the November sample run, most of the parameter's values seen at the Upper Basin sites were consistent with water of high quality. The most recent significant rain was 0.26 inches at Lake Tawakoni and 0.63 inches at Lake Fork eight days prior to the sample date. Surface water temperatures were between 12.1 and 16.2ºC at river and reservoir sites. BS-1 exceeded the numeric criteria for the stream standards for E. coli. Nitrate/nitrite levels at LT23A and LT23D exceeded reservoir screening criteria. No stream standards exist for nitrate/nitrite so screening values are used as a guide. Surface water temperatures near the dams at Lake Tawakoni and Lake Fork were 15.9 and 16.2ºC respectively. Bottom temperatures at the same sites were essentially the same as their surface temperatures with 15.8 and 16.2ºC respectively. Lake Tawakoni and Lake Fork were completely mixed.
Lower Sabine Basin Including Toledo Bend to Morgan Bluff
The November monthly sampling results were indicative of water of high quality at most sites. The area received heavy rainfall about one week prior to the sample run. During that rain event the area received close to eight inches of rain within a three-day period. The level of Toledo Bend Reservoir was recorded at 168.61 feet with seven gates discharging from the spillway, but no discharge through the generator at the time of sampling. All lake sites showed stratification, but only the very deepest station on the reservoir showed anoxic conditions at the deepest depths. The E. coli level at TB6N was above the stream standard. Station TB6N is located in a small, slow-moving bayou, and does not represent the conditions of the main body of the reservoir. Stations located in the main body of the reservoir showed no impact from the water quality conditions indicated in this backwater area.
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. The area received its last significant rainfall just over a week prior to the sample event. Around three inches of rain was recorded during a two-day period. Most sites in this section of the Basin were well mixed with only slight oxygen differences throughout the water column. No anoxic conditions were found. No recordable salinities were found at any site at any depth. Stations SRT2 and SRT1 had elevated bacterial results.
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:
Ø Upper Sabine Basin
John Payne, Upper Basin Field Office Coordinator
Ø Lower and Tidal Sabine Basin
Jerry Wiegreffe, Lower Basin Field Office Coordinator
If above are unavailable
Miles Hall, Assistant Division Manager Environmental Services
Printed Tuesday, January 28, 2003