To: Interested Parties

From: Water Resources Branch

RE: March 2006 monthly Water Quality Report

Water quality sampling was performed March 6th through March 9th. Recent weather (previous seven days) in the Sabine River Basin was warm, with daytime highs in the upper 60s to upper 80s at Lake Tawakoni and at Lake Fork. Toledo Bend Reservoir and Orange had daytime highs from the upper 60s to the low 80s. Lows ranged from the upper 30s to low 60s at Lake Tawakoni and at Lake Fork. Toledo Bend and Orange had lows ranging from the mid 30s to the mid 60s. The waters of Lake Tawakoni and Lake Fork were thermally mixed. During the 28 days prior to the sample run, the Upper Basin received 2.76 and 3.02 inches of rainfall as recorded at Lake Tawakoni and at Lake Fork, respectively. Lake Tawakoni and Lake Fork received no rainfall the week preceding the sample run. Toledo Bend and Orange received 4.52 and 2.02 inches of precipitation during the 28 days prior to the sample run.

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

Most water quality parameter measurements at Upper Basin sites were consistent with water of high quality. The level of Lake Fork was recorded at 399.09 feet msl with 8 cfs releases and the level of Lake Tawakoni was recorded at 428.77 feet msl with 6 cfs releases at the time of sampling. Stations LT23A, LT23C, LF2, and LF4 met or exceeded 105 percent dissolved oxygen saturation. Stations LT23A, LT23D, LT23C, SR22, and SR19 exceeded the recommended screening criteria for chlorophyll a. High chlorophyll a levels in conjunction with dissolved oxygen saturation values exceeding 100% often indicate algal bloom conditions.

Lower Sabine Basin Including Toledo Bend to Morgan Bluff

The March monthly sampling results were indicative of water of high quality at most sites. The area received 0.3 inches of rainfall the week prior to sampling. The level of Toledo Bend Reservoir was recorded at 165.98 feet msl with 174 cfs discharge at the time of sampling. Most reservoir stations were stratified with dissolved oxygen and temperature differences throughout the water column. All of the lake stations were well oxygenated. Stations TB6A and TB6S recorded dissolved oxygen percent saturations above 105% saturation, while Station TB6R recorded a chlorophyll a result above the recommended screening level. Stations TB8 and TB7A exceeded the recommended screening criteria for nitrate+nitrite nitrogen.

Tidal Section of the Sabine Basin below Morgan Bluff

Most sites sampled in the tidal portion of the Sabine Basin had values that are consistent with water of high quality. Although the tidal stations received no measurable rainfall in the seven days prior to the sample event, it was raining while these stations were sampled. Due to strong winds and heavy rain while sampling, surface parameters only were measured at all but one station. Surface salinities were found at all but one tidal station. The largest salinity value, 10 ppt, was found at Station BB1. A bacterial result above the numeric stream standard was also found at station BB1.


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:


      Upper Sabine Basin
Terry Wilson, Upper Basin Field Office Coordinator
903-878-2420 (

      Lower and Tidal Sabine Basin
Jerry Wiegreffe, Lower Basin Field Office Coordinator
409-746-3284 (

      If above are unavailable
John Payne, Special Projects Administrator
409-746-2192 (
Miles Hall, Resource Management/ Project Development Division Manager
409-746-2192 (


Printed Thursday, June 08, 2006 at 10:04