Natchitoches

Harry Garsee - Superintendent
City of Natchitoches
Office: (318) 352-4883

Engineer of Record:

N & A, Inc.
740 Front Street
Natchitoches, La. 71457
Rick Nowlin, P.E.
(318) 352-3665

EES Employee's Role:

A new Extended Aeration Activated Sludge Plant was constructed. The location of the facility is five (5) miles outside of the City of Natchitoches adjacent to the Red River. This facility consisted of a 20 MGD headworks with a mechanical screen, manual screen, grit chamber, and splitter box. A 50 MG earthen equalization basin, three 1.63 MG oxidation ditches with intra channel clarifiers, and a UV disinfection chamber attached to an effluent pump station. A sludge processing building consisting of a mechanical shop, chlorination room, belt press and pump room, and an operator's office. A lime silo is adjacent for sludge mixing. A sludge storage shed is located to the rear of the sludge building for sludge storage. Two circular sludge clarifiers thicken the sludge before being pumped to the belt press. The administration building has a complete wastewater laboratory MCC room, two offices, restrooms, and a kitchen/meeting room.

Contractor	Don Barron Construction
Completion Date	1993
Construction Costs	$10,000,000
Costs/Gallon	$2.04

Type of Waste	Domestic
Flow (Average)	4.9 MGD
(Hourly Peak)	16.3 MGD
Phosphorus In	0.00 MG/L
Minimum Operating Temp.	10 C
Elevation (MSL)	110.00 FT.
Hydraulic Detention Time	24.00 Hrs.
Sludge retention Time	22.00 Days

BOD In	217.00 MG/L
BOD Out	30.00 MG/L
TSS In	217.00 MG/L
TSS Out	30.00 MG/L
TKN In	25.00 MG/L

Total Reactor Volume	4.9 MG
Hydraulic Detention Time	24.00 Hrs.
Sludge Retention Time	22.00 Days
Yield	0.68 lbs. of Solids/lb. of Bod Removed Daily
Sludge Production	6,668.12 lbs./day
Food to Microorganism Ratio	0.07 lbs. BOD In/lbs. MLSS Organics
Alpha	0.85
Beta	0.97
BOD Applied	9,787.82 lbs./day
TSS Applied	9,787.82 lbs./day
Ammonia Nitrogen Applied	1,223.48 lbs./day