Preliminary Treatment

Gates

Cranks for Slide Gates at Cahokia Pump Station

Sluice Gate at East St. Louis Pump Station

The East St Louis pump station uses two types of gates:  sluice gates and slide gates.  The sluice gates control the flow of water coming into the pump station and control the flow to the barscreens.  These gates are automatically operated.  The final sluice gate is manually operated and controls the flow to different pumps.  The two slide gates are used to isolate the barscreens for cleaning.

The Cahokia pump station uses manually operated and automatically operated slide gates.  All are used at the barscreens.  The automatic gates control the flow going to each of the barscreens while the manual gates are utilized to isolate the barscreens for cleaning.

Barscreens

Barscreen at Cahokia Pump Station

Both pump stations have similar types of barscreens.  They remove trash and debris larger than an inch and a half.  Each pump station has a pair of barscreens that are mechanically raked.  The rakes are set to run when the debris building up against the barscreens affects the flow of water coming into the pump station.  The rakes pull the trash and debris up a conveyor connected to the screens.  The debris is raked upward over the top of the conveyor and falls into a dumpster.

Pumps & Pipes

East St. Louis Pumps and Force Main

The East St Louis pump station is equipped with four dry pit pumps.  The wastewater is pumped 8000 feet, or 1 ½ miles, from the East St. Louis pump station to American Bottoms through a 42 inch ductile iron force main.  During normal operation, the pump station operates using a single pump.

The Cahokia pump station is equipped with three dry pit pumps.  The water is pumped 14,000 feet, or over 2 ½ miles, to American Bottoms through a 20 inch ductile iron force main.  Similar to operation in East St. Louis, one pump is in use during normal operation.