1. Simultaneous Solutions for Aesthetics and Other Water Quality Problems Stephen Booth, PhD Craig Thompson, PE

2. Water Quality Issues ▼ Aesthetics l Taste & Odor l Color l Particulate matter ▼ Other Issues l Disinfection l DBPs and Precursors l Treatability

3. USEPA SMCLs - Aesthetics

4. USEPA SMCLs – Aesthetics (Cont’d)

5. Groundwater Aesthetics ▼ Iron-reducing bacteria and soluble iron ▼ Sulfur-reducing bacteria and sulfides ▼ High mineral content ▼ Salt water intrusion ▼ Contamination

6. Surface Water Issues ▼ Planktonic and benthic algae ▼ Proliferation of algae in reservoirs ▼ Agricultural runoff ▼ Industrial discharges ▼ Wastewater plant discharges

7. Surface Water Odor Qualities ▼ Earthy/Musty ▼ Grassy/Green Vegetation ▼ Decaying/Marshy ▼ Fishy ▼ Septic ▼ Medical/Chemical ▼ MTBE (chemical) ▼ Woody/Hay ▼ Soapy

8. After Treatment… ▼ Distribution system issues ▼ Plumbing and storage

9. Geosmin (t-1,10-dimethyl-t,9-decalol) ▼ Geo (earth) + osme = odor ▼ Customer complaints common > 10 ng/L ▼ Odor threshold at 45°C ~5 ng/L

10. 2-MIB (2-Methylisoborneol) ▼ Odor descriptors: musty, peaty, earthy, damp soil ▼ Sensitivity highly variable

11. Treatment Techniques ▼ Established: ▼ Oxidation ▼ Adsorption ▼ Emerging: ▼ Advanced Oxidation ▼ Biodegradation ▼ Alternate Adsorbents Complex design and operation Significant costs

12. Evaluating Alternatives ▼ Oxidation / Advanced Oxidation l Ozone l Chlorine dioxide l Potassium permanganate l UV + Peroxide ▼ Adsorption l GAC l PAC

13. Taste versus Safety Ratings Data from MWDSC/USBR Salinity Management Study, June 1999. Sample of five Southern California communities. Initial sample = 1503 10 = Perfectly Safe 0 = Very unsafe

14. Lake Bard Water Filtration Plant ▼ Calleguas Municipal Water District ▼ Source water is Lake Bard ▼ Seasonal algae problems results in T&O ▼ Ozone process l Oxidizes T&O l Improves micro-flocculation l High downstream filtration rates (9 gpm/ft 2 )

15. Oxygenation System Schematic

16. Tower and Eduction System

17. Jamieson Canyon Water Treatment Plant ▼ City of Napa, CA ▼ Current plant expansion: 12 to 24 mgd ▼ North Bay Aqueduct Water Quality l Episodes of elevated TOC and turbidity l Terminal Reservoir subject to algae and T&O Open (sunlight) Nutrient input from bird population

18. Raw Water Quality ParameterAverageRange Raw water TOC (mg/L) 5.71.1 - 16 Filtered water TOC (mg/L) 3.60.5 - 10 Monthly average peak raw water turbidity (NTU) 4020 – 70

19. Ozone System Design Criteria ItemValue Number of Cells5 HRT at 24 mgd5 min Ozone Dose Avg. (Max.)1.5 (3.0) mg/L Ozone Usage Avg. (Max.)250 (400) lb/day Source GasLOX

20. Jamieson Canyon WTP (Cont’d) ▼ Pre-Ozone for simultaneous benefits: l T&O treatment l Pre-oxidize without forming THMs and HAAs l Oxidation of organics and color l Lower coagulant dosage

21. Jamieson Canyon WTP (Cont’d) ▼ Pre-Ozone for simultaneous benefits: l Disinfection benefit l Ability to use settled water pipe as intermediate ozone contactor l Removal of PPCPs

22. Conclusions ▼ Taste and odor quality important to consumers ▼ Expense of T&O treatment drives us to look for multiple benefits ▼ Opportunity for creativity