Attoyac at SH 21 - TCEQ ID: 10636

Site Description

Attoyac Bayou at SH 21; 0.71 km West of the intersection of SH 21 and FM 1196; 4.77 km East of Chireno.

Segment Description

Segment 0612 - Attoyac Bayou. Attoyac Bayou is a freshwater stream measuring 81.7 miles in length from a point 3.9 km (2.4 miles) downstream of Curry Creek in Nacogdoches/San Augustine County to FM 95 in Rusk County. The designated uses for this segment include the following: high aquatic life, general, contact recreation, and public water supply. The area surrounding the watershed is managed for agricultural (cattle and poultry), silvicultural, recreational, and wildlife uses. The watershed contains many rural residents. This segment has three areas that are listed on the 303(d) list due to bacteria.

Monitoring Performed Quarterly

Field Parameters Conventional Parameters Bacterial Parameters
Dissolved Oxygen Ammonia-N E. coli
Days Since Last Significant Rainfall Chloride  
Flow Severity Chlorophyll-a  
Instantaneous Stream Flow Pheophytin-a  
pH Sulfate  
Present Weather Total Dissolved Solids (TDS)  
Secchi Transparency Total Nitrate+Nitrite  
Specific Conductance Total Phosphorus  
Total Water Depth Total Suspended Solids (TSS)  
Water Temperature    



  • Upstream April

    Facing north, looking upstream. Photo taken 2010-04-10

  • Upstream May

    Facing north, looking upstream. Photo taken 2011-05-03

  • Downstream April

    Facing south, looking downstream. Photo taken 2010-04-10

  • Downstream May

    Facing south, looking downstream. Photo taken 2011-05-03

360 Degree View - click here to open in a new window