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drawing of denitrification plant
The Town, under direction from the California Regional Water Quality Control Board, is building improvements at Wastewater Plant No. 2 to remove excess nitrogen from the Town effluent discharge to Old River.  Excess nitrogen contributes to harmful blue-green alga growth in the Delta.  Improvements being constructed include Oxidation Ditch No. 4, and Anoxic Basins No. 2, 3, and 4. The new process will remove nitrogen by first providing oxygen in the oxidation ditches to convert ammonia in the wastewater to nitrate.  Then the oxygen will be removed in the anoxic basins to convert the nitrate into pure nitrogen and oxygen that will go back into the air.  Total project cost is $18 million.  Project will be complete in Fall of 2023.
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