Characteristics and operational performance of selected WWTPs, Ontario, 2014–2017
| Plant code and parameter . | Plant A . | Plant B . | Plant C . | Plant D . | Plant E . |
|---|---|---|---|---|---|
| Types of treatment | Conventional + SF | Conventional | Conventional + SF | Conventional | Conventional (EA) |
| Effluent quality | Tertiary | Secondary | Tertiary | Secondary | Secondary |
| Disinfection type | UV | UV | Chlorine | Chlorine | Chlorine |
| Intensity/dosage | 30–40 mJ/cm2 | 30–40 mJ/cm2 | 3.1 mg/L | 5.8 mg/L | 7.3 mg/L |
| Contact time | 0.23 s | 0.23 s | 15 min | 10 min | 13 min |
| Receiver | Creek | Great Lake | River | River | River |
| Study period | November 2014–October 2015 | November 2014–October 2015 | May 2015–April 2016 | July 2015–June 2016 | December 2016–November 2017 |
| Rated capacity, m3/day | 22,727 | 24,548 | 7,200 | 81,800 | 9,320 |
| Mean daily flow, m3 | 16,900 | 15,040 | 3,040 | 42,610 | 6,750 |
| cBOD5 mean ± SD, mg/L | 1.2 ± 0.4 | 4.2 ± 2.8 | 2.1 ± 0.1 | 3.9 ± 2.3 | 3.5 ± 1.4 |
| Range | 1.0–2.0 | 2.0–11.7 | 2.0–2.3 | 2.2–10.4 | 2.0–5.8 |
| Regulatory effluent limit | 5 | 25 | 25 | 25 | 25 |
| TSS mean ± SD, mg/L | 1.7 ± 0.5 | 6.5 ± 5.8 | 2.4 ± 0.4 | 6.9 ± 3.7 | 5.9 ± 1.4 |
| Range | 1.0–2.6 | 3.0–20.5 | 2.0–3.5 | 2.3–14 | 3.9–8.2 |
| Regulatory effluent limit | 5 | 25 | 25 | 25 | 25 |
| TP mean ± SD, mg/L | 0.11 ± 0.04 | 0.3 ± 0.18 | 0.08 ± 0.02 | 0.42 ± 0.14 | 0.39 ± 0.06 |
| Range | 0.05–0.15 | 0.10–0.75 | 0.05–0.12 | 0.2–0.60 | 0.30–0.49 |
| Regulatory effluent limit | 0.3 | 1 | 0.3 | 1 | 1 |
| TAN mean ± SD, mg/L | 0.10 ± 0.03 | 8.36 ± 4.92 | 0.08 ± 0.05 | 2.06 ± 1.78 | 1.68 ± 1.60 |
| Range | 0.08–0.14 | 0.34–12.0 | 0.05–0.2 | 0.18–5.23 | 0.12–4.86 |
| Regulatory effluent limit | 1.0, 2.0* | ||||
| UAN, mean ± SD, mg/L | 0.001 ± 0.0 | ||||
| Regulatory effluent limit | 0.02 | ||||
| pH mean ± SD | 7.65 ± 0.06 | 7.20 ± 0.08 | 7.17 ± 0.12 | 7.55 ± 0.18 | 7.49 ± 0.19 |
| Range | 7.52–7.71 | 7.10–7.35 | 7.00–7.36 | 7.24–7.89 | 7.15–7.69 |
| Regulatory effluent limit | 6.0–9.5 | 6.0–9.5 | 6.0–9.5 | 6.0–9.5 | 6.0–9.5 |
| E. coli monthly GM ± SD | 1.3 ± 0.5 | 59.8 ± 75.3 | 2.4 ± 2.9 | 17.0 ± 19.2 | 48.3 ± 21.4 |
| Range, CFU/100 mL | 1.0–2.0 | 7.0–285 | 1.0–11 | 3.0–75.0 | 11.2–79.0 |
| Regulatory effluent limit | 200 | 200 | 200 | 200 | 200 |
| Plant code and parameter . | Plant A . | Plant B . | Plant C . | Plant D . | Plant E . |
|---|---|---|---|---|---|
| Types of treatment | Conventional + SF | Conventional | Conventional + SF | Conventional | Conventional (EA) |
| Effluent quality | Tertiary | Secondary | Tertiary | Secondary | Secondary |
| Disinfection type | UV | UV | Chlorine | Chlorine | Chlorine |
| Intensity/dosage | 30–40 mJ/cm2 | 30–40 mJ/cm2 | 3.1 mg/L | 5.8 mg/L | 7.3 mg/L |
| Contact time | 0.23 s | 0.23 s | 15 min | 10 min | 13 min |
| Receiver | Creek | Great Lake | River | River | River |
| Study period | November 2014–October 2015 | November 2014–October 2015 | May 2015–April 2016 | July 2015–June 2016 | December 2016–November 2017 |
| Rated capacity, m3/day | 22,727 | 24,548 | 7,200 | 81,800 | 9,320 |
| Mean daily flow, m3 | 16,900 | 15,040 | 3,040 | 42,610 | 6,750 |
| cBOD5 mean ± SD, mg/L | 1.2 ± 0.4 | 4.2 ± 2.8 | 2.1 ± 0.1 | 3.9 ± 2.3 | 3.5 ± 1.4 |
| Range | 1.0–2.0 | 2.0–11.7 | 2.0–2.3 | 2.2–10.4 | 2.0–5.8 |
| Regulatory effluent limit | 5 | 25 | 25 | 25 | 25 |
| TSS mean ± SD, mg/L | 1.7 ± 0.5 | 6.5 ± 5.8 | 2.4 ± 0.4 | 6.9 ± 3.7 | 5.9 ± 1.4 |
| Range | 1.0–2.6 | 3.0–20.5 | 2.0–3.5 | 2.3–14 | 3.9–8.2 |
| Regulatory effluent limit | 5 | 25 | 25 | 25 | 25 |
| TP mean ± SD, mg/L | 0.11 ± 0.04 | 0.3 ± 0.18 | 0.08 ± 0.02 | 0.42 ± 0.14 | 0.39 ± 0.06 |
| Range | 0.05–0.15 | 0.10–0.75 | 0.05–0.12 | 0.2–0.60 | 0.30–0.49 |
| Regulatory effluent limit | 0.3 | 1 | 0.3 | 1 | 1 |
| TAN mean ± SD, mg/L | 0.10 ± 0.03 | 8.36 ± 4.92 | 0.08 ± 0.05 | 2.06 ± 1.78 | 1.68 ± 1.60 |
| Range | 0.08–0.14 | 0.34–12.0 | 0.05–0.2 | 0.18–5.23 | 0.12–4.86 |
| Regulatory effluent limit | 1.0, 2.0* | ||||
| UAN, mean ± SD, mg/L | 0.001 ± 0.0 | ||||
| Regulatory effluent limit | 0.02 | ||||
| pH mean ± SD | 7.65 ± 0.06 | 7.20 ± 0.08 | 7.17 ± 0.12 | 7.55 ± 0.18 | 7.49 ± 0.19 |
| Range | 7.52–7.71 | 7.10–7.35 | 7.00–7.36 | 7.24–7.89 | 7.15–7.69 |
| Regulatory effluent limit | 6.0–9.5 | 6.0–9.5 | 6.0–9.5 | 6.0–9.5 | 6.0–9.5 |
| E. coli monthly GM ± SD | 1.3 ± 0.5 | 59.8 ± 75.3 | 2.4 ± 2.9 | 17.0 ± 19.2 | 48.3 ± 21.4 |
| Range, CFU/100 mL | 1.0–2.0 | 7.0–285 | 1.0–11 | 3.0–75.0 | 11.2–79.0 |
| Regulatory effluent limit | 200 | 200 | 200 | 200 | 200 |
SF, sand filtration; EA, extended aeration, i.e., no screening and primary clarification; CBOD5, 5-day carbonaceous biochemical oxygen demand; TSS, total suspended solids; TP, total phosphorus; TAN, total ammonia nitrogen; UAN, unionized ammonia nitrogen; SD, standard deviation; GM, geometric mean; CFU, colony forming units.
*May–November, 1 mg/L; December–April, 2 mg/L.