(1980 to
date) and average MCI values predicted from the MCI – site altitude regression equation
revealed areas on the ring plain where observed stream health is better, worse, or equal to that
which is predicted. This analysis suggested that approximately 65.3% of the area met or
exceeded the stream health predicted by the MCI – altitude relationship, with the remaining
34.7% falling just one quality class below that predicted.
Given the intensity of land-use on the
Executive Audit and Risk Agenda March 2023
Executive Audit and Risk Agenda July 2023
2.4 Irrigation to Land of Leachate
Situated north of the compost and vermiculture operations is a series of leachate ponds that collects
run-off from these activities. In addition to the collection of leachate and stormwater that falls in the
composting area, wash down water from the truck wash is also collected in this pond; which further
dilutes the compost leachate.
Figure 2 highlights the area in purple, where water from these ponds are irrigated to land. Typically
irrigation
indicated that all discharges had occurred when the river flow was above the
consented 5 m³/s.
The Waiongana Stream hydrology displays a natural rapid rise and fall (typical of Taranaki ring plain
streams) which allows for a limited window of opportunity when treated wastewater can be discharged
above the minimum consent limit. The consent holder has access to the Taranaki Regional Council web site
(www.trc.govt.nz), which provides current river flow and water levels for the Waiongana Stream
Waitotara. The remainder or irrigators are
generally located inland, between Inglewood and Eltham.
1.1.7 Irrigation systems
In general there are two types of irrigation methods; surface and pressurised. The majority of irrigation
systems currently in operation in the province fall in to the pressurised category. Pressurised systems can be
further differentiated based on the method of operation and equipment used. A summary of the systems
encountered in the region is given below.
K-line and
Company. Through an automated water
level sensor system, the Company can monitor the residual flows in the Manganui River and Mangaotea
Stream, water levels in the race and lake and how much rain is falling locally. This has allowed the Company
to manage race flows to minimise flooding, and has greatly improved the Company’s compliance with
residual flow requirements.
1.3 Resource consents
The Company holds 23 resource consents, the details of which are summarised in the table below.
irrigation methods; surface and pressurised. The majority of irrigation
systems currently in operation in the province fall in to the pressurised category. Pressurised systems can be
further differentiated based on the method of operation and equipment used. A summary of the systems
encountered in the region is given below.
K-line and long-lateral types – Impact sprinklers mounted on moveable laterals (Photo 1)
These are the most common systems found in the region, as they are a low cost
modelled results
from Fraser (2022).
Attribute band
Southern
Hill
Country
Coastal
Terraces
Pātea
Volcanic
Ringplain
Waitara
Northern
Hill Country
A 64% 0% 39% 27% 54% 84%
B 11% 3% 12% 7% 12% 6%
C 10% 17% 16% 11% 7% 2%
D 16% 79% 32% 55% 27% 8%
The modelled estimates show that the majority of total stream reach across the Waitara, Southern Hill
Country and Northern Hill Country FMUs fall in band A for visual clarity (54%, 64% and
conditions of this consent, the conditions of this consent shall prevail.
2. The consent holder shall maintain the structure in a safe and sound state such that:
(a) It does not fall into a state of disrepair and continues to function effectively for the
purpose it was designed; and
(b) Its structural integrity is maintained.
3. The consent holder shall ensure that upstream and downstream passage is provided
past the weir and intake structure for trout and native fish in all their life