To: Interested Parties

From: Water Resources Branch

RE: September 2004 monthly Water Quality Report

This is the Sabine River Authority Water Quality Report for September 2004. Water quality sampling was performed September 13th through September 16th. Recent weather (previous seven days) in the Sabine River Basin was warm, with daytime high air temperatures from the low 80s to the mid 90s at Lake Tawakoni and at Lake Fork. Toledo Bend Reservoir and Orange had daytime highs from the low 80s to the mid 90s. Lows ranged from the mid 50s to the upper 60s at Lake Tawakoni and at Lake Fork. Toledo Bend and Orange had lows ranging from the low 60s to the mid 70s. Lake Tawakoni and Lake Fork exhibited thermal stratification. During the 28 days prior to the September sample run, the Upper Basin received 2.42 and 2.11 inches of rainfall as recorded at Lake Tawakoni and Lake Fork, respectively. The week prior to the sample run, Lake Tawakoni and Lake Fork did not receive any rain. Toledo Bend and Orange received 1.02 and 3.11 inches, respectively, during the 28 days preceding the sample run.

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

For the September sample run, most water quality parameter measurements at Upper Basin sites were consistent with water of high quality. The level of Lake Fork was recorded at 401.73 feet msl with 64 cfs releases and the level of Lake Tawakoni was recorded at 436.61 feet msl with 5 cfs releases at the time of sampling. LT23D, LT23C and SR11 did not meet the stream standards numeric criteria for pH. These sites along with LF3 had high levels of dissolved oxygen with greater than 100 percent dissolved oxygen saturation. Chlorophyll a values at LT23A, LT23D, LT23C LF3 and LF4 were above the screening levels for reservoir sites. Elevated chlorophyll a levels and high dissolved oxygen with greater than 100 percent dissolved oxygen saturation indicate algal bloom conditions. These conditions may also lead to elevated pH levels. SR16 exceeded the stream standards numeric criteria for E. coli.


Lower Sabine Basin Including Toledo Bend to Morgan Bluff

The September monthly sampling results were indicative of water of high quality at most sites. No rainfall was measured during the seven days prior to sampling. The level of Toledo Bend Reservoir was recorded at 168.43 feet msl with 204 cfs discharge at the time of sampling. All reservoir stations were stratified, with pH and dissolved oxygen differences throughout the water column. Anoxic conditions were found at the deepest depths at most of the lake stations. pH values exceeded stream standards at stations TB7A, TB6R, and TB6K. Stations TB8, TB7A, TB6R, and TB6K had a dissolved oxygen percent saturation value above 100%. These factors together indicate an algal bloom on the northern sections of Toledo Bend. A chlorophyll a value above the screening criteria was also found at station TB6F.

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. The tidal stations received 0.42 inches of rainfall the day prior to the sample run. All of the sites in this section of the Basin showed some stratification, but no anoxic conditions were found. Surface salinities were found at all tidal stations with the highest value of 10 ppt found at station BB1. The overall greatest salinity value of 20 ppt was found at station SRT1 at a depth of 10.6 meters. All but one of the tidal stations recorded Enterococcus results that were above the stream standard criteria. This is most likely a result of the rain the day prior to sampling that was preceded by over a week with dry conditions.

 

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 Monday, May 23, 2005 at 11:07