2019-2020 monitoring year, with most
commencing irrigation in late October and concluding in March. Rainfall recorded at the Council’s
monitoring locations over the summer irrigation period ranged between 85% and 114% of historical mean
values. Total usage during the 2019-2020 irrigation season, across all exercised irrigation consents was 8,835
ML. This was more than that used during the preceding 2018-2019 monitoring year, when 56 irrigation
consents were exercised, and a total usage of 6,906 ML. …
cyanobacteria were higher than in the previous
three seasons, and similar to the preceding two seasons, probably a reflection of the relative amounts of
rainfall causing freshes that scour streambeds of periphyton.
page
Timely reporting of the results of bacteriological water quality and cyanobacteria numbers/cover was
undertaken by use of the Taranaki Regional Council website (www.trc.govt.nz) and LAWA website
(www.lawa.org.nz), as well as liaison with territorial local
2018-June 2019) 9
Figure 4 Daily abstraction volumes under consent 7470-1.2 (July 2009-June 2019) 10
Figure 5 Maximum daily abstraction rate under consent 7470-1.2 (July 2009-June 2019) 10
Figure 6 Observed groundwater levels GND2102 and rainfall (July 2018-June 2019) 11
Figure 7 Observed groundwater levels GND2102 and abstraction (July 2018-June 2019) 12
Figure 8 Observed groundwater levels GND2103 and rainfall (July 2018-June 2019) 12
Figure 9 Observed groundwater levels
Daily abstraction volumes under consent 7470-1.2 (July 2009-June 2018) 10
Figure 5 Maximum daily abstraction rate under consent 7470-1.2 (July 2009-June 2018) 10
Figure 6 Observed groundwater levels GND2102 and rainfall (July 2017-June 2018) 11
Figure 7 Observed groundwater levels GND2102 and abstraction (July 2017-June 2018) 12
Figure 8 Observed groundwater levels GND2103 and rainfall (July 2017-June 2018) 12
Figure 9 Observed groundwater levels GND2103 and abstraction (July
.................................................................................................................................................. 8
2.3 CLIMATE .................................................................................................................................................... 8
Table 2: Kaka Road Rainfall Events 2011-17 ............................................................................................. 10
Table 3: High Intensity rainfall data (NIWA) for site ................................................................................ 10
2.4 HYDROLOGY / HYDROGEOLOGY
wet weather from mid July to early
August 2008 resulted in further intermittent overflows of very dilute, treated wastewater to
the stream until mid August 2008. Similar intermittent overflows were recorded after very
wet weather late in the 2009-2010 period, over a four week period in September 2010 and
again, more briefly late in the 2010-2011 period. Seven intermittent overflows, each of one to
four days duration, occurred following heavy rainfall events in the 2011-2012 period. One
climate, with abundant rainfall and high sunshine hours, makes the region lush, green
and fertile.
Rainfall
Annual rainfall varies throughout the region. Some coastal areas receive less than 1,400 mm annually, while
the summit of Mount Taranaki receives around 7,500 mm.
Heavy rainfall events do occur and there can be extremes. In 2012 heavy rain caused a number of slips on
the coastal road around Mount Taranaki, including a large slip at Oākura that covered the road, burying a
REMEDIATION NZ LTD Page 7
Document No: RU-P-650-0500-A
Revision No: V1.3
Date: 1 0-9-2018
Controller: C Kay
page
Leachate & Stormwater
Management Plan
f) Any conspicuous change in the colour visual clarity;
g) Any emissions of objectionable odour;
h) The rendering of fresh water unsuitable for consumption by farm animals; and
i) Any significant adverse effects on aquatic life.
3.4.3 Climate
NIWA virtual Climate Station -38.975, 174.525 Thirty years of rainfall and
nitrogen concentration in the pond and the rainfall 30 days prior to the
sampling event. This was based on 7 ammoniacal nitrogen concentrations
measured between October 2017 and April 2019. The relationship has an
R2 value of 74%.
Using this relationship, the monthly rainfall from 2018 was used to
calculate monthly nitrogen concentrations in the pond. The concentration
was converted to a loading rate in kg/ha/month based on the volume
irrigated (calculated from 2018 irrigation hours and an
variation of annual
rainfall
mm y-1r
usRainDays10 Catchment average frequency of rainfall > 10 mm days month-1
usRainDays20 Catchment average frequency of rainfall > 20 mm days month-1
usRainDays100 Catchment average frequency of rainfall > 100 mm days month-1
segAveTCold Segment mean minimum winter air temperature degrees C x 10
Hydrology MeanFlow Estimated mean flow m3 s-1
nNeg Mean number of days per year on which flow was less
than that of the previous day
Year-1