Case Study: Disinfection byproducts in a recently constructed public water supply Maria O’Connell, P.E. Kristine Wheeler, P.E. New York State Department of Health Glens Falls District Office
Service Area Intake Wilton Stillwater V/T Saratoga Hills Burnt Hills/ Ballston Lake & CPWA Global Foundries
SCWA Water System Hudson River Low Lift Pumps Raw Water Transmission Main Chemical Injection: Permanganate, Coagulant (PACL) and Powder Activated Carbon (PAC) Mixing Basin Filter Pumps Membrane Filter Racks (14 MGD) Chemical Injection: Chlorine and Caustic Soda (pH adjustment) Clearwell for chlorine contact time (1 MG) High Lift Pumps Finished Water Transmission Main (≈30 miles) Finished Water Storage at Global Foundries (5 MG)
Purchase Customers Wilton Burnt-Hills-Ballston Lake Clifton Park Water Authority State Farm Insurance (via CPWA) Round Lake (via Clifton Park) Stillwater Village Stillwater Town Global Foundries Moreau (emergency connection pending 2013) Mechanicville (possible emergency connection)
Global Foundries
Source: Hudson River Turbidity Color Natural Organic Matter (NOM) Total Organic Carbon (TOC) Algae
Low Lift Pump Station
Chemical Injection Sodium Permanganate Polyaluminum Chloride (PACL) Powder Activated Carbon (PAC) ◦Taste & Odor ◦DBP Precursors Sodium Hypochlorite Caustic Soda
Mixing Basin Pre-filter Chemical Mixing Short Detention Time No Significant Pretreatment Enhanced Coagulation BAT for DBPs
Membrane Filters Pall Aria Membrane Microfiltration LT2ESWTR Giardia & Crypto Removal Dissolved Matter, DBP Precursor Removal Membrane Fouling
Lagoons No Discharge, no SPDES permit Increased filter cleaning frequencies caused increased recycle rates Increased DBP Precursor Loading
Clearwell & CT
Finished Water Transmission Main About 30 miles 36” then 30” diameter Detention time Two smaller diameter pipes ◦Back up ◦Lower detention time
Finished Water Storage Located at Luther Forest Technology Campus 5 Million Gallons Booster Chlorination Recirculation Dedicated to Global Foundries
Total Trihalomethanes 2012 Running Annual Average (ug/l) Public Water Supply NameQ1Q2Q3Q4 Burnt Hills Ballston Lake WD Clifton Park Water Authority Round Lake Village Saratoga County Water Authority Saratoga Hills Park (Stillwater) State Farm Insurance (Bldg 2) Stillwater Village Stillwater WD # Wilton Water & Sewer Authority Moreau Town (Queensbury)
Total Trihalomethanes - CPWA 2012 Running Annual Average (ug/l) Sample SiteQ1Q2Q3Q4 Blue Spruce Water Storage Tank Boyack Rd Bruno Rd. Storage Tank Grooms Tavern Jonesville Fire Dept.* Riverview Rd.* Round Lake Rd. Metering* State Farm Regional Office (Bldg 1) *Sites only have 1 year of data
Haloacetic Acids 2012 Running Annual Average (ug/l) Public Water Supply NameQ1Q2Q3Q4 Burnt Hills Ballston Lake WD Clifton Park Water Authority Round Lake Village Saratoga County Water Authority Saratoga Hills Park (Stillwater) State Farm Insurance Stillwater Village Stillwater WD # Wilton Water & Sewer Authority Moreau Town (Queensbury)
Haloacetic Acids - CPWA 2012 Running Annual Average (ug/l) Sample SiteQ1Q2Q3Q4 Blue Spruce Water Storage Tank Boyack Rd Bruno Rd. Storage Tank Grooms Tavern Jonesville Fire Dept.* Riverview Rd.* Round Lake Rd. Metering* State Farm Regional Office *Sites only have 1 year of data
Factors for Evaluation Groundwater vs Surface Water Stage 1 vs Stage 2 DBP Rule Conventional vs Membrane Finished TOC Comparable NOM Species Reactivity Varies Detention Time
Challenges Round Lake is on SNC List Stillwater Pending SNC List Stage 1 vs. Stage 2 DBP Rule Public Notification
Looking Forward Permanganate has been added PAC trial at Raw Water PS Evaluate other oxidants and disinfectants Tank Aeration Increased Flows Distribution System Management Operator Training Carbon Filtration? Pretreatment?
Thank you!