Wastewater Treatment Plant
Phone Number: 936-633-0288
- The staff of the WWTP is available for school
tours of the facility. For any questions or information
regarding the City's WWTP, please call (936) 633-0288
- Free RV Dump Station Monday through Friday 8
am to 4 pm. Saturday use may be available if the owner has made
arrangements during the previous week.
- The Industrial Pretreatment Program is
conducted from this department. Any questions or comments
concerning the Program can be directed to the Environmental
Manager by calling (936) 633-0288.
The Process of Wastewater
Sewage discharge from Lufkin's
residential, commercial and industrial contributors is collected at
the WWTP. The influent sewage is pumped into the Plant and
introduced to forced air, which will increase the microbial activity
and aid in the removal of grit and grease.
The influent enters a separation stage of solid settling. The
untreated sludge is Primary Sludge. It is thickened and then pumped
to a Holding Tank which also receives thickened Secondary Sludge.
The Holding Tank Sludge is pumped to three Anaerobic Digesters and
held for a minimum of 15 days at 100°F to 105°F. The Anaerobic
Sludge is hauled to a state permitted application site for
beneficial use and also to the county landfill.
The Primary water flows to the Aeration Basin. This is the heart of
the treatment plant. The Primary water is introduced to forced air
and Secondary Sludge being returned from the Final Clarifiers. The
Primary water provides food, the Secondary Sludge provides
microorganisms and the air provides respiration for the
microorganisms. In the Aeration Basin, or Biological Reactor, the
waste is broken down by the microorganisms into a stable inert form.
The Secondary Sludge from the Basin is pumped to the Final
Clarifiers where it is allowed to separate the solids from the
water. Part of the solids are returned to the Aeration Basin as food
and the rest is thickened by the Gravity Belt Thickener then pumped
to the Holding Tank. The clear water, or Effluent, is sent to the
Chlorine Contact Chamber where it is held in the presence of
chlorine to kill the microorganisms. The Effluent is then introduced
to sulfur dioxide which removes the chlorine before it is discharged
into Hurricane Creek.
Conventional Waste Activated Sludge
Design Flow: 11.3 Million
Gallons per Day
Peak Flow: 11,875 Gallons
Average Flow 2005: 6.4 Million Gallons
Average CBOD 2005: 6 mg/L; 97 % Removal
Average TSS 2005: 8 mg/L; 95 %
Annual Cost 2005: $0.758 per 1,000
TCEQ Permit Effluent Parameters 30 Day Avg.
Carbonaceous Biochemical Oxygen Demand (CBOD)
Total Suspended Solids (TSS)
Total Chlorine Residual (Effluent)