scheme 6
Table 2 Gauging results for gaugings undertaken in relation to the Manganui River residual flow 14
Table 3 Details of consents and special conditions in relation to abstraction rates, discharge rates and
water levels and the recording 18
Table 4 Incidents where recorded flows/water levels did not meet consent requirements. 19
Table 5 Summary of summer Manganui River daily water temperatures (°C) prior to the increase in
residual flow to 400 L/s (1992-2002) and for the
and
liner installation construction details for new ponds. For existing ponds, we provide
estimated leak rates and comments on leak detection monitoring and maintenance (see
Section 4).
• Environmental considerations for siting new ponds (see Section 5).
1.2 Scope of work
We have carried out the following:
• Desk top review of available geological information including:
- Townsend et al., 2008. Geology of Taranaki Area. Institute of Geological and Nuclear
monitoring, enables the Council to continually re-evaluate its approach
and that of consent holders to resource management and, ultimately, through the refinement of methods
and considered responsible resource utilisation, to move closer to achieving sustainable development of the
region’s resources.
1.1.4 Evaluation of environmental and administrative performance
Besides discussing the various details of the performance and extent of compliance by Methanex, this report
also assigns them a rating
including loss of gate control, the scheme operated with few major issues. In comparison with
previous monitoring years, compliance with residual flow requirements was high, continuing on from the
significant improvement noted in the 2014-2015 monitoring period. Management of the level of Lake
Opunake improved from the previous period, as maintenance works and changes to operations led to a
reduction in the rate of water lost during station shutdowns. Unfortunately, the maintenance works required
(NZTM)
3.4 Legal description of property at site of activity (refer to land title or rates notice)
_________________________________________________________________________________
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3.5 Assessment/Valuation number of property (refer to land title or rates notice)
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3.6 What is
to
manage the channel alignment.
Works required to protect roads and bridges are the responsibility of the asset owner but advice will be
provided.
Where erosion control works will be of benefit to more than one landowner, a subsidy from the Councils
General Rate may be available from the Regional Council. No subsidy will be available for the protection
of District Council or national assets such as highway and rail bridges.
Currently the key location where channel
rating for their environmental and administrative performance during the period
under review.
Environmental performance is concerned with actual or likely effects on the receiving environment from the
activities during the monitoring year. Administrative performance is concerned with the Company’s
approach to demonstrating consent compliance in site operations and management including the timely
provision of information to Council (such as contingency plans and water take data) in accordance
regularly. A backup system allowed the collection of a limited range of critical data, which allowed
Trustpower to continue operating the scheme in line with other conditions (e.g. residual flows, race water
levels etc.). There was only one occasion when required flow rates were not complied with. This related to a
severe weather event resulting in a high race water level but was of short duration (no more than 2.5 hours).
Compliance with flushing flow requirements was good with regards to the
category of
mesotrophic to possibly mildly eutrophic (mildly nutrient enriched). However, taking into
page
account the influence of suspended sediment in this reservoir, and the moderately low
chlorophyll levels, the classification is more appropriately mesotrophic. Previous trending of
this water quality data over time found a very slow rate of increase in trophic level. An update
of the trend report (for the period 1990-2014) has confirmed this very slow, insignificant rate
the Council, which is the body
responsible for managing the asset.
1.3 Duration and review of the Plan
The duration of the Plan is ten years from the date of formal preparation and acceptance by
Council. This Plan has also been prepared with a 30-year time horizon. Maintenance costs
and rates are current to June 2020.
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Okato Scheme Asset Management Plan
27 August 2020 4
The Plan will be updated, after the proposed capital works are completed and then reviewed