Executive summary
Good during the monitored period
DO averaged 10.55 mg/L, the 5th percentile was 9.59 mg/L, and the minimum was 8.71 mg/L. Maximum ammonia/ammonium was 0.54 mg/L. This rating is a screening interpretation, not a regulatory ecological-status classification.
- Overall river-health screening rating: Good during the monitored period.
- Lowest DO was 8.71 mg/L at 2026-05-26 19:00:00; mean DO was 10.55 mg/L.
- The strongest DO relationship is typically water temperature: in this dataset r = -0.86, meaning warmer water coincided with lower oxygen.
- Ammonia/ammonium is also strongly associated with lower DO: r = -0.35.
- Diurnal behaviour is visible: average DO is lowest at about 20:00 and highest at about 12:00.
- Largest turbidity spike was 12208.43 NTU at 2026-06-12 06:00:00.
- Largest rainfall hour was 2.80 mm at 2026-06-03 10:00:00.
Note: This is an analytical screening report. It supports investigation and operational decision-making, but it is not a formal regulatory classification.
Water-quality and weather summary
| count | mean | std | min | 25% | 50% | 75% | max | |
|---|---|---|---|---|---|---|---|---|
| Ammonia/ammonium (mg/L) | 1514.00 | 0.32 | 0.05 | 0.18 | 0.30 | 0.33 | 0.36 | 0.54 |
| Conductivity (µS/cm) | 1514.00 | 359.73 | 28.88 | 219.34 | 351.48 | 366.04 | 378.75 | 398.56 |
| Dissolved oxygen (mg/L) | 1514.00 | 10.55 | 0.66 | 8.71 | 10.04 | 10.51 | 11.02 | 12.59 |
| do-pct" | 1514.00 | 97.34 | 3.11 | 88.97 | 95.60 | 96.71 | 98.33 | 111.89 |
| pH | 1514.00 | 7.99 | 0.12 | 7.69 | 7.92 | 7.97 | 8.03 | 8.60 |
| Water temperature (°C) | 1514.00 | 11.80 | 2.14 | 7.86 | 9.97 | 11.80 | 13.51 | 16.84 |
| Turbidity (NTU) | 1514.00 | 21.38 | 314.94 | 4.03 | 7.20 | 8.90 | 11.87 | 12208.43 |
| Air temperature (°C) | 1514.00 | 12.81 | 5.31 | 1.10 | 9.20 | 12.40 | 15.97 | 30.40 |
| Humidity (%) | 1514.00 | 73.92 | 16.30 | 32.00 | 61.00 | 77.00 | 88.00 | 100.00 |
| Rain (mm/hour) | 1514.00 | 0.08 | 0.27 | 0.00 | 0.00 | 0.00 | 0.00 | 2.80 |
| Atmospheric pressure (hPa) | 1514.00 | 994.84 | 8.71 | 968.20 | 989.30 | 994.35 | 1001.80 | 1011.30 |
| Cloud cover (seconds/hour) | 1514.00 | 61.84 | 38.59 | 0.00 | 23.00 | 76.00 | 99.00 | 100.00 |
| Wind speed (km/hour) | 1514.00 | 12.92 | 6.25 | 0.20 | 8.30 | 12.85 | 17.50 | 29.20 |
| Sunshine (seconds/hour) | 1514.00 | 1689.17 | 1732.75 | 0.00 | 0.00 | 713.93 | 3600.00 | 3600.00 |
Relationships affecting dissolved oxygen
DO correlations
| Correlation with DO mg/L | |
|---|---|
| Water temperature (°C) | -0.86 |
| Air temperature (°C) | -0.52 |
| pH | 0.49 |
| Ammonia/ammonium (mg/L) | -0.35 |
| Conductivity (µS/cm) | -0.24 |
| Humidity (%) | -0.13 |
| Atmospheric pressure (hPa) | 0.12 |
| Sunshine (seconds/hour) | 0.11 |
| Rain (mm/hour) | -0.07 |
| Cloud cover (seconds/hour) | -0.06 |
| Wind speed (km/hour) | -0.06 |
| Turbidity (NTU) | -0.01 |
Best lag relationships
| best_lead_hours | correlation | |
|---|---|---|
| variable | ||
| Water temperature (°C) | 4 | -0.92 |
| Air temperature (°C) | 8 | -0.83 |
| pH | 21 | 0.54 |
| Ammonia/ammonium (mg/L) | 0 | -0.35 |
| Sunshine (seconds/hour) | 9 | -0.28 |
| Conductivity (µS/cm) | 19 | -0.28 |
| Wind speed (km/hour) | 7 | -0.20 |
| Cloud cover (seconds/hour) | 14 | -0.16 |
| Rain (mm/hour) | 8 | -0.10 |
| Turbidity (NTU) | 11 | -0.02 |
Interpretation: Strong negative relationships indicate variables that rise when DO falls. In rivers, water temperature is a physical driver because warm water holds less oxygen. Ammonia/ammonium can indicate pollution and oxygen-demanding processes such as nitrification or organic decomposition. Rainfall effects can be indirect: runoff may raise turbidity and nutrients while conductivity can fall from dilution.
Time-series patterns
Diurnal effects
Hourly averages show whether readings follow a day/night rhythm. A typical river signal is oxygen rising during daylight photosynthesis and falling overnight due to respiration.
Obvious anomalies and watch-points
| variable | value | reason | |
|---|---|---|---|
| timestamp | |||
| 2026-04-21 12:00:00 | pH | 8.41 | robust z-score 5.9 |
| 2026-04-21 13:00:00 | pH | 8.49 | robust z-score 7.0 |
| 2026-04-21 14:00:00 | pH | 8.52 | robust z-score 7.4 |
| 2026-04-21 15:00:00 | pH | 8.51 | robust z-score 7.3 |
| 2026-04-21 16:00:00 | pH | 8.47 | robust z-score 6.7 |
| 2026-04-21 17:00:00 | pH | 8.37 | robust z-score 5.4 |
| 2026-04-22 11:00:00 | pH | 8.31 | robust z-score 4.6 |
| 2026-04-22 12:00:00 | pH | 8.39 | robust z-score 5.7 |
| 2026-04-22 13:00:00 | pH | 8.49 | robust z-score 7.0 |
| 2026-04-22 14:00:00 | pH | 8.54 | robust z-score 7.7 |
| 2026-04-22 15:00:00 | pH | 8.53 | robust z-score 7.6 |
| 2026-04-22 16:00:00 | pH | 8.49 | robust z-score 7.0 |
| 2026-04-22 17:00:00 | pH | 8.40 | robust z-score 5.8 |
| 2026-04-22 18:00:00 | pH | 8.28 | robust z-score 4.2 |
| 2026-04-23 10:00:00 | pH | 8.30 | robust z-score 4.5 |
| 2026-04-23 11:00:00 | pH | 8.36 | robust z-score 5.3 |
| 2026-04-23 12:00:00 | pH | 8.43 | robust z-score 6.2 |
| 2026-04-23 13:00:00 | pH | 8.52 | robust z-score 7.4 |
| 2026-04-23 14:00:00 | pH | 8.56 | robust z-score 8.0 |
| 2026-04-23 15:00:00 | pH | 8.55 | robust z-score 7.8 |
| 2026-04-23 16:00:00 | pH | 8.51 | robust z-score 7.3 |
| 2026-04-23 17:00:00 | pH | 8.42 | robust z-score 6.1 |
| 2026-04-23 18:00:00 | pH | 8.28 | robust z-score 4.2 |
| 2026-04-24 11:00:00 | pH | 8.27 | robust z-score 4.0 |
| 2026-04-24 12:00:00 | pH | 8.37 | robust z-score 5.4 |
| 2026-04-24 13:00:00 | pH | 8.48 | robust z-score 6.9 |
| 2026-04-24 14:00:00 | pH | 8.54 | robust z-score 7.7 |
| 2026-04-24 15:00:00 | pH | 8.52 | robust z-score 7.4 |
| 2026-04-24 16:00:00 | pH | 8.49 | robust z-score 7.0 |
| 2026-04-24 17:00:00 | pH | 8.40 | robust z-score 5.8 |
| 2026-04-24 18:00:00 | pH | 8.27 | robust z-score 4.0 |
| 2026-04-25 11:00:00 | pH | 8.30 | robust z-score 4.5 |
| 2026-04-25 12:00:00 | pH | 8.42 | robust z-score 6.1 |
| 2026-04-25 13:00:00 | pH | 8.52 | robust z-score 7.4 |
| 2026-04-25 14:00:00 | pH | 8.56 | robust z-score 8.0 |
| 2026-04-25 15:00:00 | pH | 8.55 | robust z-score 7.8 |
| 2026-04-25 16:00:00 | pH | 8.50 | robust z-score 7.1 |
| 2026-04-25 17:00:00 | pH | 8.41 | robust z-score 5.9 |
| 2026-04-25 18:00:00 | pH | 8.28 | robust z-score 4.2 |
| 2026-04-26 11:00:00 | pH | 8.34 | robust z-score 5.0 |
| 2026-04-26 12:00:00 | pH | 8.43 | robust z-score 6.2 |
| 2026-04-26 13:00:00 | pH | 8.54 | robust z-score 7.7 |
| 2026-04-26 14:00:00 | pH | 8.60 | robust z-score 8.5 |
| 2026-04-26 15:00:00 | pH | 8.60 | robust z-score 8.5 |
| 2026-04-26 16:00:00 | pH | 8.57 | robust z-score 8.1 |
| 2026-04-26 17:00:00 | pH | 8.49 | robust z-score 7.0 |
| 2026-04-26 18:00:00 | pH | 8.36 | robust z-score 5.3 |
| 2026-04-27 12:00:00 | pH | 8.31 | robust z-score 4.6 |
| 2026-04-27 13:00:00 | pH | 8.34 | robust z-score 5.0 |
| 2026-04-27 14:00:00 | pH | 8.35 | robust z-score 5.1 |
Cause-and-effect hypotheses to test next
- Temperature → lower dissolved oxygen: expected and strongly supported by this data.
- Sunlight → photosynthesis → higher DO and pH: supported by the diurnal DO pattern and positive pH/DO relationship.
- Rainfall → runoff/dilution: rainfall can spike turbidity and nutrients while lowering conductivity through dilution.
- Ammonia/ammonium → oxygen stress risk: elevated ammonia is associated with lower DO and should be investigated around event windows.