Table 2. UV-treated final effluent water quality parameters measured in the North End Sewage Treatment Plant.c.
| Sampling events | ||||||
|---|---|---|---|---|---|---|
| Parameters | Oct-22-2019 (#1) | Nov-28-2019 (#2) | Dec-18-2019 (#3) | Feb-6-2020 (#4)‡ | Mean | SD |
| BOD (mg/L) | 19.5a | 13 | 18 | 26 | 19.13 | 4.64 |
| cBOD (mg/L) | 4 | 5 | 7 | 7 | 5.8 | 1.5 |
| COD (mg/L) | 51.5a | 66 | 94 | 89 | 75.13 | 17.25 |
| sCOD (mg/L) | 25 | 51 | 68 | 63 | 51.8 | 19.2 |
| E. coli (counts/100 ml) | 60 | 60 | 90 | 1080 | 322.5 | 437.5 |
| Fecal coliforms (counts/100 ml) | 100 | 20 | 40 | 640 | 200 | 295.3 |
| Grab Temperature (°C) | 13.4 | 14.1 | 14.1 | 12.7 | 13.6 | 0.7 |
| Mean (Ambient) Temperature (°C) | 2.7 | −6.6 | −17.0 | −17.1 | −9.5 | 9.5 |
| NH4-N (mg/L) | 5.9 | 26.3 | 34.3 | 34.9 | 25.4 | 13.5 |
| NOx-N (mg/L) | 7.5 | 5.3 | 3.3 | 2.1 | 4.5 | 2.4 |
| pH | 7.12 | 6.81 | 6.79 | 6.99 | 6.93 | 0.14 |
| PO4-P (mg/L) | 1.3 | 2.6 | 1.2 | 1.0 | 1.5 | 0.7 |
| Precipitation (mm)a | 4.8 | 0 | 1 | 1.6 | 1.85 | 1.8 |
| TN (mg/L) | 15.4b | 40.7 | 49.8 | 50.5 | 39.1 | 14.22 |
| TOC (mg/L) | 19.8b | 21.2 | 29.6 | 34.4 | 26.25 | 6.02 |
| TP (mg/L) | 1.67b | 3.43 | 1.69 | 1.69 | 2.12 | 0.76 |
| TS (mg/L) | 1,065 | 886 | 818 | 598 | 841.8 | 193 |
| TSS (mg/L) | 19.5b | 6 | 10 | 18 | 13.38 | 5.58 |
| Turbidity (NTU) | 12.25b | 4.2 | 6.3 | 9.2 | 7.99 | 3.03 |
| grab filtered UVT (%) | 56.7 | 52.1 | 45.8 | 46.9 | 50.4 | 4.4 |
Notes.
- BOD
- biochemical oxygen demand
- cBOD
- Carbonaceous Biochemical Oxygen Demand
- COD
- chemical oxygen demand
- sCOD
- soluble chemical oxygen demand
- NH4-N
- ammonium-nitrogen
- NOx-N
- nitrogen oxides –nitrogen
- PO4-P
- orthophosphate
- TN
- total nitrogen
- TP
- total phosphorus
- TOC
- total organic carbon
- TS
- total solids
- TSS
- total suspended solids
- UVT
- Ultraviolet transmittance
a
Cumulative amount of rainfall over three days.
b
Parameters measured the day before and the day after were averaged and used to estimate parameters of sample date.
c
Modified from Jankowski et al. (2022).