2023 Quarterly Results
November 2023
Water quality was excellent at 39-Mangaohuinga Stream and good at all other sites, except for water clarity which was low at sites 40, 41 & 42.
E. coli concentrations were exceptionally low at all 4 sites (≤ 110). Nitrate concentrations were well below toxicity levels at all sites being lowest at 42-Kiritehere Stream (< 0.01 mg/L) and highest at 40-Wairoa Stream (0.25 mg/L). Ammonia concentrations were exceptionally low at all 4 sites (< 0.005 mg/L). The combined concentration of Nitrate + Ammonia was below 0.5 mg/L at all sites. Ecological impacts, including problematic growth of algae and/or aquatic plants and loss of sensitive aquatic species are likely when the combined concentration of nitrate and ammonia regularly exceed 0.5 mg/L. Dissolved reactive phosphorus concentrations were low at all 4 sites (≤ 0.009). Water clarity was excellent at 39-Mangaohuinga Stream and poor at all sites (≤ 1.46 m), relative to the national bottom line (1.34 m).
Collection date: 10 November 2023
August 2023
Overall water quality was good except for water clarity which was low at all 4 sites. E. coli concentrations were exceptionally low at all 4 sites (≤ 54). Nitrate concentrations were below toxicity levels at all sites being lowest at 42-Kiritehere Stream (0.07 mg/L) and highest at 39-Mangaohuinga Stream (0.70 mg/L). Ammonia concentrations were low at 3 out of 4 sites (≤ 0.007 mg/L) and higher at 40-Wairoa Stream (0.02 mg/L). Sites 39 and 40 (Mangaohuinga stream and Wairoa stream) both had a combined concentration of Nitrate + Ammonia equivalent to 0.70 mg/L. Ecological impacts, including problematic growth of algae and/or aquatic plants and loss of sensitive aquatic species are likely when the combined concentration of nitrate and ammonia regularly exceed 0.5 mg/L. Dissolved reactive phosphorus concentrations were low at all 4 sites (≤ 0.01). Water clarity was poor at all sites (≤ 0.95 m), relative to the national bottom line (1.34 m).
Collection date: 25 August 2023
May 2023
E. coli concentrations were low at 3 out of 4 sites (≤ 230) and were slightly elevated at 42-Kiritehere Stream (290). Nitrate concentrations were below toxicity levels at all sites being lowest at 42-Kiritehere Stream (0.08 mg/L) and highest at 40-Wairoa Stream (0.69 mg/L). Ammonia concentrations were exceptionally low at 3 out of 4 sites (< 0.005 mg/L) and higher at 40-Wairoa Stream (0.02 mg/L). 40-Wairoa Stream and 39-Mangaohuinga Stream both had a combined concentrations of Nitrate + Ammonia exceeding 0.5 mg/L. Ecological impacts, including problematic growth of algae and/or aquatic plants and loss of sensitive aquatic species are likely when the combined concentration of nitrate and ammonia regularly exceed 0.5 mg/L. Dissolved reactive phosphorus concentrations were low at 3 out of 4 sites (≤ 0.01) and elevated at 39-Mangaohuinga Stream (0.011 mg/L). Water clarity was poor at all sites (≤ 0.77 m), relative to the national bottom line (1.34 m).
Collection date: 18 May 2023
Water Quality Summary 2022
The water quality dial for Marokopa River combines data collected at 6 monitoring sites between January 2022 – February 2023, representing 39 individual samples. Nitrates were low. E. coli and dissolved reactive phosphorus (DRP) were elevated, while water clarity was low indicating sediment loading. Arrows indicate an increase or decrease in values compared to the sub-catchment baseline (2016 – 2020). An increase in water clarity is positive for river health while an increase in all other attributes may impair river health.
