Rathbun Regional Water Association, Inc.
Water Treatment PlantSource Water Evaluation
Chariton River WTP Intake
Overview of Treatment
Principles of Operation
• Oxidation and Precipitation• Coagulation• Flocculation• Sedimentation• Filtration• disinfection
SuperPulsating Clarifiers
Solids Contact Basins
Chemical Feed
Filtration
High Service
Analyzers
Performance Based Training
Jan-11 Feb-11 Mar-11 Apr-11 May-11 Jun-11 Jul-11 Aug-11 Sep-11 Oct-11 Nov-11 Dec-110.0
0.1
1.0
10.0
100.0
1000.0
Turbidity ProfileRaw Max Sed Max Filter Combined
Tu
rbid
ity
(NT
U)
Source Water Evaluation
1. Organics/Manganese2. Taste and Odor3. Turbidity4. Alkalinity5. Farm Chemical Application6. Bacteria/Cryptosporidium
Organics and Manganese
• Often Bound together• Removal contrast based on pH (TOC/Mn)• Sodium Permanganate• Rainfall events push organics into lake
– Leaves, trees, brush, etc.• Lake stratification promotes Mn build up• Low dissolved oxygen concentration
– New Caisson provide relief from lake bottom
36 “ Screened Intake
Taste and Odor
• Spring flush of nutrients into lake• Dry summers influence stratification
– Sunlight penetration due to settling• Geosmin and Methoisoborneol -2 (MIB)
– Encapsulate in blue-green algae cell walls– Release when cyanotoxins are present
• Phosphorus reduction can help
Turbidity
• Very low turbidity is hard to treat (< 5ntu)• High turbidity can be expensive (>100ntu)• Rathbun range is 3 – 500 ntu. Avg. is 25 ntu.• Sediment removal is a great benefit.• Rainfall events > 1” above and below intake
are detrimental to optimization.
Discharge 2010
Alkalinity
• Requirement for coagulation buffer– 0.5 mg/L plus 35 mg/L residual
• Extreme flooding (2007-2008) downstream• Rathbun uses Sodium Hydroxide to buffer
– 1.65 mg/L dosage to achieve 1 ppm residual
New Caisson
Farm Chemical Application
• Atrazine and Nitrogen• Nearly eliminated since RLWA improvements• Carbon caps on filters• Powder Activated Carbon
Syngenta Atrazine
Bacteria/Cryptosporidium
• Manure Runoff• Ecoli and Fecal Coliform• Chlorine Demand• 4-log removal of crypto• Conservation practice to maintain low influent
Questions???• [email protected]
• (800) 233.8849
• www.rrwa.net
• www.rathbunlandwateralliance.blogspot.com
