and detaching or detached mats accumulating on the river’s edge triggered the
‘Alert’ level at the same four sites (Waingongoro River at Ohawe, Kaupokonui River at the mouth, and
Waiwhakaiho River at the last riffle and at Merrilands Domain) on a total of 8 surveys. Levels of
cyanobacteria were higher than in the previous season; and lower than the preceding three seasons,
probably a reflection of the relative amounts of rainfall causing freshes that scour streambeds of
Operations and Regulatory Commiittee Agenda July 2024
caddisflies). The MCI index (widely used to monitor macroinvertebrates in
streams) is high (typically >100) in streams dominated by mayflies, stoneflies and caddisflies and low
(typically <80) in streams dominated by worms, snails and chironimids.
In Taranaki, nutrients are not such a problem because of fast flowing and relatively short rivers and
streams. High rainfall leads to frequent flushing events in rivers and streams that provide natural
scouring. Even in summer, most Taranaki rivers do
on aquatic life.
4.4.3 Climate
NIWA virtual Climate Station -38.975, 174.525 Thirty years of rainfall and evaporation data is
summarised in Table 1 below
Table 1: NIWA Virtual Climate Station 30-year data for a site near Uruti Site
Uruti Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec Total
Rainfall 120.0 107.0 119.2 151.2 181.2 189.5 181.8 178.0 175.4 188.4 149.4 149.0 1890.
Evaporation 134.5 108.0 88.6 52.7 31.1 21.4 25.4 39.0 57.5 85.1 109.3 126.0 878.6
4.4.4
there will always be a delay
between sample collection, analysis, receiving results and
delivering the public health advice. This is primarily because
bacteria need time to grow in the lab as part of the analytical
process. While we can try to minimise the time between
sample collection and delivery of the information, there will
always be a delay.
By collecting all-weather water quality data, it may be
possible to develop a predictive rainfall risk model, which can
Revised Assessment of Environmental Effects (AEE) - June 2020
performance for consent 7470-1.1 16
List of figures
Figure 1 Location of TTR site production and monitoring bores 5
Figure 2 Daily abstraction volumes under consent 7470-1.1 (July 2014-June 2015) 10
Figure 3 Daily abstraction volumes under consent 7470-1.1 (2009-2015) 10
Figure 4 Maximum daily abstraction rate under consent 7470-1.1 (2014-2015) 11
Figure 5 Maximum daily abstraction rate under consent 7470-1.1 (2009-2015) 11
Figure 6 Observed groundwater levels and rainfall
between the
relatively ‘shallow’ groundwater table and the Haehanga Stream.
This may vary at different times of the year, for example, depending
page
5
on rainfall and stream flows. This information is needed to assess
the impact of the discharge to the irrigation areas (and potentially
the composting pads and ponds) on the groundwater and the
subsequent effect due to contaminated groundwater entering
surface water.
18 An initial review undertaken by LEI identified a
Mangati Catchment Joint Annual Report 2022-2023
d) Construction timetable for the erosion and sediment control works and the bulk earthworks
proposed;
e) Maintenance, monitoring and reporting procedures;
f) Rainfall response and contingency measures including procedures to minimise adverse effects in
the event of extreme rainfall events and/or the failure of any key erosion and sediment control
structures;
g) Procedures and timing for review and/or amendment to the erosion and sediment control
measures listed in the ESCP; and,