wastewater treatment system, including the installation of an additional soakage
trench. The wastewater treatment system at the Retreat did not adversely affect the water quality of the
local freshwater and coastal environments. Although high bacteriological results were returned from the
routine sampling round in January 2019, these counts were attributed to surface runoff draining the
upstream agricultural catchment, following the rains that preceded the sampling. Two follow-up samples
were
was also some replacement of square kerbing with radial.
Mangaotaki Rockfall (2008)
Heavy rain triggered a large rock fall on 4th August 2008 at the Mangaotaki Bluffs. The large
rocks blocked SH3 for almost 48hrs and a route detour through local council roads was required
during this time.
Two stock truck effluent disposal facilities have been built along the route, one in each of the
regions – the Taranaki one at Ahititi on the northern
site.
1.3 Resource consents
1.3.1 Water abstraction permit
Section 14 of the RMA stipulates that no person may take, use, dam or divert any
water, unless the activity is expressly allowed for by a resource consent or a rule in a
regional plan, or it falls within some particular categories set out in Section 14.
The primary effects of taking and diverting groundwater is the potential for the water
table to be lowered, consequently impacting on nearby surface water such as the
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
westerly wind. The monthly rainfall was 210 mm of
rain as recorded at the Inglewood WWTP TRC weather station.
The step screen was operating and wastes were fully contained. Slight odour was noticeable in the vicinity of
the step screen. One aerator was operating on the aeration pond, which was a turbid, light grey brown
colour. The pond was discharging into the main pond.
The main pond had a normal level of 0.76 m, with a relatively clear, green grey colour and rippled surface.
The
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
period was lower than normal in
comparison with historical surveys. The total number of samples falling within the “Alert” or “Action”
categories (40% of samples) across the 16 recognised bathing sites was the highest recorded. However, it
should be noted that the “Action” category is the only category for which swimming is not recommended.
In the 2017-2018 season, 79% of all samples met the national bathing guideline. Of the 21% of samples that
exceeded the guideline, 11% arose
sound state such that:
a. They do not fall into a state of disrepair and continue to function effectively for the
purpose they were designed;
b. Their structural integrity is maintained;
c. There is no settlement or loss of foundation material; and
d. Erosion of the foreshore or seabed which has been demonstrated by monitoring to
be a direct result of the rock revetment structure, is minimised as far as
practicable.
19. Within 6 months of completion of the rock revetment
undertaken on 20 February 2015 38
Table 10 Results of rain event monitoring – discharge and Puremu
Stream samples, 13 August 2014 39
Table 11 Results of rain event monitoring - Manganaha Stream, 13
August 2014 40
Table 12 Biomonitoring sites in the Puremu and Manganaha Streams
related to the Colson Road Landfill. 41
Table 13 Chemical analysis of Colson Road Landfill groundwater
sampled 9 June 2015 44
Table 14 Air deposition monitoring results for 13 January- 4 February
2015 45
bunded to contain any stormwater and organic leachate, and exclusion drains, bunds,
and diversions are situated around the ponds to divert clean stormwater away from
operational areas.
74. Stormwater runoff typically occurs immediately following rain events. The stormwater
volume depends on a number of factors, including the moisture content of the soil and
the intensity of the rain. The majority of contaminants contained within the stormwater
will be in the ‘first flush’ of water leaving