To: Interested Parties

From: Water Resources Branch

RE: July 2005 monthly Water Quality Report

This is the Sabine River Authority Water Quality Report for July 2005. Water quality sampling was performed July 11th through July 14th. Recent weather (previous seven days) in the Sabine River Basin was warm, with daytime highs from the mid 80s to the upper 90s at Lake Tawakoni and at Lake Fork. Toledo Bend Reservoir and Orange had daytime highs from the mid 80s to the upper 90s. Lows ranged from the low 70s to the mid 70s at Lake Tawakoni and at Lake Fork. Toledo Bend and Orange had lows ranging from the upper 60s to the mid 70s. The waters of Lake Tawakoni and Lake Fork were thermally stratified. During the 28 days prior to the sample run, the Upper Basin received 0.93 and 1.63 inches of rainfall as recorded at Lake Tawakoni and at Lake Fork, respectively. Lake Tawakoni and Lake Fork received 0.34 and 0.73 inches of rainfall the week preceding the sample run. Toledo Bend and Orange received 3.53 and 3.22 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 401.66 feet msl with 64 cfs releases and the level of Lake Tawakoni was recorded at 434.76 feet msl with 6 cfs releases at the time of sampling. Stations LF2, LF3, LT23A and LT23C exceeded Stream Standards numeric criteria for pH while exceeding 100 percent saturation for dissolved oxygen. Station SR19 also exceeded 100 percent saturation for dissolved oxygen. Stations LT23C, LT23D, LT23A, LF3, LF4, LF2, 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. Station SR16 fell below the Stream Standards numeric criteria for dissolved oxygen and Station SR14 exceeded the Stream Standards numeric criteria for E. coli.


Lower Sabine Basin Including Toledo Bend to Morgan Bluff

The July monthly sampling results were indicative of water of high quality at most sites. The area received 1.5 inches of rain during the week of sampling. The level of Toledo Bend Reservoir was recorded at 167.58 feet msl with 204 cfs discharge at the time of sampling. Most reservoir stations were stratified with dissolved oxygen and pH differences throughout the water column. No anoxic conditions were found. Stations TB8, TB7A, TB6R, TB6K and TB6LN had elevated dissolved oxygen percent saturation. Stations TB6R, TB6J, and TB6K had pH values that were above the Stream Standards numeric criteria. Several of the stations with elevated pH readings also had over 100% saturation of dissolved oxygen at the surface. These factors together potentially indicate an algal bloom on the reservoir. Stations TB6R and SR2 also displayed a chlorophyll a result above the recommended screening criteria.

Tidal Section of the Sabine Basin below Morgan Bluff

Most sites sampled in the tidal portion of the Sabine Basin had values consistent with water of high quality. Tidal stations received just over 0.3 inches of rainfall the week prior to sampling with more significant rains just beyond that timeframe. All stations in this section of the Basin showed some stratification, but no anoxic conditions were found. Surface salinities were found at Stations ICW1, BB1, SRT1A, SRT1B and SRT1. The largest salinity value, 14 ppt, was found at Station SRT1C at a depth of 11.5 meters. Elevated bacteria levels were found at stations BB1 and SRT1C.

 

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:

 

      Upper Sabine Basin
Terry Wilson, Upper Basin Field Office Coordinator
903-878-2420 (twilson@sra.dst.tx.us)

      Lower and Tidal Sabine Basin
Jerry Wiegreffe, Lower Basin Field Office Coordinator
409-746-3284 (jwiegreffe@sra.dst.tx.us)

      If above are unavailable
John Payne, Special Projects Administrator
409-746-2192 (jpayne@sra.dst.tx.us)
or
Miles Hall, Resource Management/ Project Development Division Manager
409-746-2192 (mhall@sra.dst.tx.us)

 

Printed Tuesday, December 13, 2005 at 12:35