sites are monitored for ammonia. Three
out of four sites fall within band A and one
site in band B. At these sites, ammonia is
likely to have little to no effect on all but the
most sensitive species. Modelled estimates
support the monitored results, with
approximately 68% in band A and 32% in
band B (Figure 4).
Four sites are monitored for nitrate, all of
which fall in band A. At these sites, nitrate is
likely to have little to no effect on aquatic
life. Modelled estimates largely
Consents & Regulatory Committee agenda October 2021
Stream, were due principally to resident wild fowl populations in the vicinity of
recreational usage sites (as confirmed by inspections and more recently by DNA marker
surveys).
In terms of E. coli, bacteriological water quality in the latest survey period was similar in
comparison with historical surveys. The total number of samples falling within the “Alert”
or “Action” categories (28% of samples) was equal to the long-term average and was
strongly influenced by samples at two urban sites
sampled on 3 May 2017 31
Table 7 Chemical analysis of the Puremu Stream, sampled on 23 May 2017 33
Table 8 Results of metal analysis undertaken on 3 May 2017 34
Table 9 Results of metal analysis undertaken on 23 May 2017 35
Table 10 Results of rain event monitoring – discharge and Puremu Stream samples, 23 August 2016 37
Table 11 Results of rain event monitoring - Manganaha Stream, 23 August 2016 38
Table 12 Biomonitoring sites in the Puremu and Manganaha Streams related to the
Executive Audit and Risk agenda June 2024
overabundance of algae and aquatic weeds,
impact on the growth of sensitive species, or
even become toxic to freshwater organisms.
Five sites are monitored for ammonia, all of
which fall within band A. At these sites, ammonia
is not likely to have any toxic effect, even on the
most sensitive species. Modelling estimates
(Figure 4) however, suggest that around 66% of
rivers or streams are in band A, while 34% are in
band B.
Five sites are monitored for nitrate. One
River water quality
Nutrients
Ammonia, nitrate, and phosphorus are important for plant growth, but in excess amounts can cause
problems in freshwater. They can lead to an overabundance of algae and aquatic weeds, impact on the
growth of sensitive species, or even become toxic to freshwater organisms.
One site is monitored for ammonia, and falls in band A. At this site, ammonia is likely to have little to no
observed effect on ecosystem health. Modelled estimates supports the
Port Area Industrial Catchments Annual Report 2022-2023
STDC STDC Kaponga, Manaia, Pātea, and Waverley wastewater treatment plant monitoring report 2019-2020
groundwater
bore was in poor condition. All activity still appeared to have ceased at the
Derby Road North site.
10 February 2014
Inspection was conducted in conjunction with groundwater sampling:-
• No material had been stored or spread via this site for some years.
• The old cells and stormwater ponds were full of rain water.
• No sheen was evident, but some odour was observed immediately downwind
of the cells during groundwater sampling.
• No other issues were noted.