2023 Quarterly Results
November 2023
Overall, water quality at Mangaorongo stream was fair on 14th November 2023. E. coli concentrations were slightly elevated (350). Nitrate and Ammonia concentrations were well below toxicity levels (Nitrate 0.53 mg/L; Ammonia 0.005 mg/L). Dissolved Inorganic Nitrogen (DIN) was slightly elevated (0.54 mg/L), potentially impacting river health[1]. Dissolved reactive phosphorus was also slightly elevated (≥ 0.013 mg/L). Water clarity was excellent (3.38 m) relative to the national bottom line (0.61 m).
Collection date: 14 November 2023
September 2023
Overall, water quality at Mangaorongo stream was good on 11th September, except for a slightly elevated concentration of Dissolved Inorganic Nitrogen. E. coli concentrations were low (120). Nitrate concentrations were well below toxicity levels (0.61 mg/L). Ammonia concentrations were exceptionally low (< 0.005 mg/L). Dissolved Inorganic Nitrogen (DIN) exceeding 0.5 mg/L, potentially impacting the health of the river1 . Dissolved reactive phosphorus was low (≥ 0.008 mg/L). Water clarity was excellent (1.55 m), relative to the national bottom line (0.61 m).
Collection date: 11 September 2023
May 2023
E. coli concentrations were low at all sites (≤ 96). Nitrate concentrations were well below toxicity levels at all sites being lowest at 1-Waikawau River and 2- Manganui River (≤ 0.08 mg/L) and greater at 3-Mangaorango Stream (0.63 mg/L). Ammonia concentrations were low at all sites (≤ 0.007 mg/L). 3- Mangaorango Stream had a Dissolved Inorganic Nitrogen (DIN) concentration exceeding 0.5 mg/L, potentially impacting the health of the river1 . Dissolved reactive phosphorus concentrations were elevated at all sites (≥ 0.011 mg/L). Water clarity was excellent at 2-Manganui River and 3-Mangaorango Stream (≥0.99 m) but was poor at 1-Waikawau River (0.46 m), relative to the national bottom line (0.61 m).
February 2023
2022 Summary
The water quality dial for Awakino & Tasman combines data collected at 6 monitoring sites between January – December 2022, representing 47 individual samples. Nitrate was low, while water clarity was high, indicating low concentrations of suspended sediment. E. coli was elevated and dissolved reactive phosphorus (DRP) was slightly elevated. Arrows indicate an increase or decrease in values compared to the sub-catchment baseline (2015 – 2020). An increase in water clarity is positive for river health while an increase in all other attributes may impair river health.
2021 Summary
E. coli and DRP are the main contaminants of concern.
Sediment appears to be elevated in the upper Awakino River, reflected by measurements taken at Gribbon Road.
Overall, those sites monitored by WRC exhibited higher E. coli concentrations compared to KCRC sites. This may relate to the greater number of samples collected at WRC sites, capturing seasonal peaks in more detail.
Over all sites in Awakino River and Tasman – Manganui River is the cleanest site and Gribbon Road is the poorest performing site.
Attribute bands
A (or blue is the best) through to E (red) which is the worst.
