TABLE 1.
Characteristics of the four reclaimed water systems studied
| Characteristic | California | Florida | Massachusetts | New York |
|---|---|---|---|---|
| Treatment process | Screening, flow equalization, trickling filters, primary and secondary clarification, flocculation, denitrification, filtration, disinfection system, and two reclamation storage reservoirs; trickling filters with tertiary sand filtration | Activated sludge with Bardenpho and secondary filtration; approx 150 collection system pump stations | Single anoxic; MBR (Zenon but switched to Torrey flat plate prior to the fall sampling) with nitrification and denitrification system; 2.57 × 107-liter equalization tank with a 13,200-liter/min submersible lift station | Anoxic and aerobic; MBR (Zenon) in the basement of a 293-unit high-rise building |
| Plant capacity | 88,960 liters/day | Average, 2.9 × 107 liters/day; full capacity, 3.4 × 107 liters/day | 950,000 liters/day but if needed can expand to 4.2 × 107 liters/day, a capacity that is attainable during high-flow seasons (i.e., full-scale activity and use of the sports stadium that it serves) | Generates 95,000 liters/day reclaimed water, 34,000 liters/day of which is for toilet flushing and 43,500 liters/day of which is for the cooling tower |
| Disinfection | Chlorine | Chlorine | Chlorine | UV and ozone |
| Storage | Open reservoir | Open reservoir (6.84 m deep with a useable storage vol of approx 2.11 × 108 liters) | 3.79 × 106-liter tank | 75,700-liter tank |
| Reuse type | Irrigation (landscaping) | Irrigation (residential, golf, schools, etc.) | Toilet flushing and urinals at stadium | Irrigation, toilet flushing, cooling tower |
| pH range | 7.07-9.60 | 7.12-8.19 | 7.32-8.94 | 6.12-7.62 |
| Conductivity (μS/cm) | 1,360-2,029 | 518-1,601 | 735-1,461 | 175-914 |
| Turbidity (NTU) | 0.67-12.7 | 0.58-16.2 | 0.23-25.2 | 0.06-2.20 |
| Water temp (°C) | 14.1-25.1 | 21.1-30.1 | 2.4-29.7 | 20.8-33.2 |
| TOC concn (mg/liter) | 12.8 ± 1.9 | 7.2 ± 0.8 | 3.8 ± 1.2 | 2.7 ± 0.5 |
| BDOC concn (mg/liter) | 6.2 ± 1.4 | 1.4 ± 0.8 | 0.6 ± 0.4 | 0.4 ± 0.2 |
| AOC concn (μg/liter) | 1,407 ± 983 | 1,141 ± 503 | 459 ± 467 | 149 ± 109 |
| Alkalinity (mg of CaCO3/liter) | 236 ± 28 | 205 ± 9 | 145 ± 16 | 33 ± 10 |
| NH3-N concn (mg/liter) | 7.8 ± 10 | 0.1 ± 0.2 | 0.04 ± 0.2 | 0.01 ± 0 |
| NO3-N concn (mg/liter) | 6.2 ± 10 | 0.7 ± 1 | 2.5 ± 1 | 24.5 ± 10 |
| P concn (mg/liter) | 11 ± 3 | 4 ± 2 | 22 ± 12 | 2 ± 0.4 |