Drinking Water Technical Assistance

Water Treatment Plant and Distribution System

KY Water and Wastewater Operators Association57th Annual Conference

Louisville, Kentucky

Water Treatment Plant and Distribution System

Water Treatment Plant

Water Treatment PlantAre DBPs being formed in the treatment process?• Pre-oxidant?• Point of Chlorination?

– C-T• Coagulant dosage?

– TOC Removal• Enhanced coagulation• Alternative compliance (next slide)• Requirements

• Step 2

Operating filters properly? • Backwash Triggers• Backwash Procedure Meeting turbidity requirements?• AWOP goals

Source Source Water Alkalinity (mg/L as Ca Co3Water

0 to 60 >60 to 120 >120TOC (mg/L)>2.0 - 4.0 35% 25% 15%>4.0 - 8.0 45% 35% 25%

>8.0 50% 40% 30%

Alternative TOC compliance criteria 1. Source water TOC <2.0 mg/L

- Calculated quarterly as a RAA- Used on a monthly basis only when raw water TOC <2.0 mg/L

2. Treated water TOC <2.0 mg/L- Calculated quarterly as a RAA- Used on a monthly basis - Treated TOC sampled no later than at CFE

3. Raw water SUVA ≤2.0 L/mg-m- Calculated quarterly as a RAA- Also used on a monthly basis

4. Treated water SUVA ≤2.0 L/mg-m- Calculated quarterly as a RAA- Also used on a monthly basis - Treated SUVA sampled no later than at CFE

5. Raw water TOC<4.0 mg/L; Raw water Alkalinity >60 mg/L; TTHM <40 µg/L; HAA5 <30 µg/L- All parameters based on a RAA, computed quarterly- DBP compliance samples used to qualify for this criteria

6. TTHM <40 µg/L and HAA5 <30 µg/L with only chlorine for disinfection- Only plants that use free chlorine a the primary disinfectant

Distribution SystemAre DBPs a problem? • Representative sampling using a

hydrant and/or tap sampler – Meeting minimum chlorine

residual?• Can changing tank operation

improve water quality?– Meeting pressure requirements– Fire Protection– Quantity

• Flushing program?– Auto Flushers

• Setting goals? – Compliance– AWOP

Questions?? Comments??

Drinking Water Technical AssistanceDon DeKoster—502-429-7122

Jackie Logsdon—270-824-7529Russ Neal—502-564-3410 ext.4969Eric Sutton—502-564-3410 ext.4989