Wastewater System

The Water & Wastewater Board began construction of the first wastewater treatment plant for the City of Satsuma in July 1995. This facility was placed into service in February 1997; marking the first time in the history of Satsuma that the city provided Board controlled sewage treatment for its citizens. The plant is constructed on 76 acres of land adjacent to Bayou Sara and has a capacity of 999,999 gallons per day treatment.

Our wastewater system consists of the Satsuma Wastewater Treatment Plant, 20 pump stations, 36 miles of PVC (polyvinylchloride) sewer mains, and 733 manholes, serving 2300 customers. The pump stations range in size from 2.4 horsepower to 25 horsepower.

The following is a brief description of the normal flow pattern through the plant under design conditions. Raw sewage from the collection sytem and main lift station enters the plant via a 12-inch force main at a header. The header distributes the flow to 3 static screens for solids removal. The screens are designed to remove relatively large objects such as sticks, rocks, etc. All solids will slough off screen into a metal shoot to channel the debris into the dumpster. These dumpsters are handled and maintained by the contracted solid waste handler.

Screened wastewater flows to the splitter box for distribution to the 2 aerated chambers. In the aeration tanks, the wastewater is biologically treated by bacteria and other microorganisms. During the time the wastewater is in the tank, or " detention time", bacteria assimilate the organic matter in the wastewater, thereby "cleaning" the wastewater, and also create new cell tissue. Waste products of this process include carbon dioxide and water, both of which are excreted into the wastewater. Sludge which has settled in the clarifiers also has many microorganisms that can feed on the organic matter in the wastewater. This sludge, called "activated sludge", is pumped from the clarifier and returned back to the aeration tanks where it is mixed with the incoming wastewater. The return activated sludge/wastewater mixture is called "mixed liquor". From the aeration tanks mixed liquor flows into the secondary clarifiers. Settable solids in the mixed liquor settle in the clarifiers, where sludge collection from sloped sides move the sludge to a center trough. A portion of the sludge removed from the clarifier bottom collection trough is pumped back to the aeration tanks (return sludge) to maintain the microorganism population. The remaining sludge, called "waste sludge" is pumped to the activated waste lagoon for further processing.

Effluent from the clarifiers flows to the post aeration chamber to increase the dissolved oxygen concentration to support aquatic life. After the last aeration chamber effluent flows to the ultraviolet channel. In this channel, UV is provided to disinfect the wastewater prior to discharge via effluent pump station to Bayou Sara.

The wastewater discharged from the treatment plant is tested according to ADEM standards and must meet treatment limits for dissolved oxygen, total suspended solids, carbonaceous biochemical oxygen demand, pH, enterococci, TKN, nitrite plus nitrate, and ammonia. This testing is performed by plant operators on site and by a private laboratory.