Environmental flows and levels; and take limits
Flow connects the whole story - freshwater ecosystems rely on water body’s natural flow variability and levels to function!
Our position in a nutshell
New Zealand rivers are highly variable. They can rapidly change between high flow and low flow states very quickly. Freshwater ecosystems and the species that live in them rely on this variability to thrive.
Environmental flows and levels is an inclusive term that encompasses ecological flows, cultural flows and the flows required for social (including human health and well-being), recreation and economic activities. (Footnote 1) Ecological flows are the flows that water bodies themselves need for their natural processes, including ecosystem health to support species to thrive in habitats ki uta ki tai (from the mountains to the sea).
The different flow types that are important for the variability in rivers natural systems, include:
flushing flows that can clear out periphyton and sediment,
median annual low flow (MALF) that indicate the lowest flow level you could expect naturally in a system,
flood flows that help to form new channels, move boulders, and maintain the natural form and character of a river. This is particularly important for braided river systems which change their course more often, and
a variety of flow types that support fish life-cycles such as cueing migration, opening river mouths so fish can move between fresh and sea water, and flows that over top the banks. Many indigenous species spawn on the banks of rivers and require variability.
The ecological flow recommendations in the draft National Environmental Standard for ecological flows (draft NES Flows) are not stringent enough. More recent science (footnote 2 and 3) has found that allocation of more than 20 percent of MALF will have a detrimental effect (i.e. moderate to major change to natural structure and ecosystem functions with greater risk) on ecosystem health, while allocation to 10 percent will have a high level of protection on ecological values. Unless more recent, regional specific studies have been completed – your regional plan should set allocation take limits at around 10 percent of MALF to be precautionary and protect ecological values. (Footnote 4)
You will need to differentiate between naturalised and observed MALF and have a qualified hydrologist complete this work. You should reassess how appropriate this management tool will be in the future considering it is a backward-looking statistic, rather than a tool to project the critical thresholds in future climate and flow variability. It must be completed at the stream reach scale and the National database can support this work.
You will need to consider decisions about allocation and flow requirements in an interconnected way - the same way that water seamlessly flows between various water body types itself. For example, groundwater takes can have a significant cumulative effect on surface water.
Footnotes
1. Richter, B.D.; Davis, M. M.; Apse, C. And Konrad, C. (2012). Short Communication: A Presmptive Stanndard for Environmental Flow Protection. River reserve and application, River Res. Applic, 28: 1312 – 1321. DOI: 10.1002/rra.1511
2. Richter, B.D.; Davis, M. M.; Apse, C. And Konrad, C. (2012). Short Communication: A Presmptive Stanndard for Environmental Flow Protection. River reserve and application, River Res. Applic, 28: 1312 – 1321. DOI: 10.1002/rra.1511
3. Hayes, J. W. (2023). Review of environmental flow limits for the Wairau River in the proposed Marlborough Environment Plan, and of consent applications for converting Class B to Class A allocations. Prepared for: Nelson-Marlborough Fish and Game Council. Fin & Flow Consulting Report No. F&F2023-1. 64 p.
4. Richter, B.D.; Davis, M. M.; Apse, C. And Konrad, C. (2012). Short Communication: A Presmptive Stanndard for Environmental Flow Protection. River reserve and application, River Res. Applic, 28: 1312 – 1321. DOI: 10.1002/rra.1511
The NPS-FM directive
You must set rules for environmental flows and levels in your regional plan that will provide for the compulsory values of ecosystem health, human contact, threatened species and mahinga kai. Other values may be developed by the community. Along with the ecological flows that all species need throughout their entire life cycle to thrive, environmental flows also need to provide for other values including recreational flow needs, flows sufficient for swimming where that is valued, wai tapu, and natural flows that reflect the personality of the individual water body.
Environmental flows and levels are the equivalent of target attrib ute states. They are the numbers measured in water bodies (such as flow in cumecs in a river or the level of a lake or groundwater) that need to be achieved to enable the environmental outcomes associated with the values to be achieved. This must include the flows needed for an ecosystem to function and thrive. You will need to identify those environmental flows for each water body (not just the FMU) and write them down as a rule in your regional plan. This may require multiple flow numbers on a single water body to provide for different flows at different times of the year. The flows should reflect the requirements of all values; for example, flows that support indigenous freshwater species spawning on the banks of rivers while also providing flows that water users may need for rafting or kayaking.
Policy 4 directs you to manage freshwater as part of New Zealand’s response to climate change and that means taking into account modelled changes in rainfall that may affect river flows and aquifer recharge and building resilience in to how you set environment flows and levels in your regional plan.
Take limits are the numbers, expressed as rules in your regional plan, that make sure that those environmental flows and levels are achieved. They are the amount of water that can be taken and indicate when a take must reduce or cease.
Environmental flows and levels and take limits must be rules in your regional plan. This is so that, if you choose, existing consents can be reviewed under section 128 of the RMA 1991, to update them to reflect the new regime.
Clause 3.17 (1)(c) of the NPS-FM asks you to state in your regional plan whether existing water permits will be reviewed to comply with new environmental flows and levels (including when you will review them, and which water permits you will review). Reviews will help meet Policy 11 which requires you to phase out all existing over-allocation and avoid over-allocation in the future. You must allocate water in a sustainable way, and you cannot over-allocate it. See our practice note on protecting water bodies and freshwater ecosystem health.
The draft National Environmental Standard for Ecological Flows (draft NES-Flows) suggested a take limit of up to 30-40 percent of MALF and some regional plans currently allocate this or more water. Clause 3.17(4) of the NPS-FM directs you to identify take limits that are specific to the relevant water body, it’s interconnected water bodies and their associated ecosystems, including the frequency and duration of the lowered flows or levels. Take limits may therefore have to change.
You must include criteria in your regional plan to approve water permit transfers and improve how to allocate water. You must also encourage methods in your regional plan for efficient water use. The mindset must switch from allocation of water for activities – to allocation of water for the water body first as is required through Te Mana o te Wai.
Since 2014 (when the NPS-FM was first introduced), you have been required to use a freshwater accounting system. A freshwater accounting system is fundamental for good decision making around water allocation.
You will need to use techniques such as models, estimates and meters to ensure all measures on allocated water are accounted for and that resilience and contingency is included to deliver a complete and robust water allocation framework. Estimates of weekly averages will not be as useful when you get closer to allocation limits and monitoring the instantaneous and daily use (in L/s or m3/s) will become critical. Better assessments of Permitted Activities may be necessary.
What do we want to see?
We want to see naturally resilient water bodies and freshwater ecosystems that are not stressed by decisions that result in over-allocation of water resource.
The NPS-FM tells you to think differently about freshwater management and you must identify what environmental flows and limits are needed by the water body and freshwater ecosystem first. The take limit may be smaller and the minimum flow higher than what you currently allow for activity’s now, but you must find ways to deliver on policy 11 and phase out over-allocation and stop future over-allocation.
Once allocation decisions have ensured the health and well-being of water is protected, then the needs of people (such as drinking water) must be secured. Allocation to support people’s social, and economic, well-being can be offered last. To calculate this, you should determine the pattern of use, instantaneous take and the volume for calculating takes for weekly and annual allocation.
This starts with you setting an allocation limit of around 10 percent of MALF if you do not have recent flow studies for your region. Anything over 20 percent of MALF has been found to have detrimental effects on ecosystem health (footnote 5). Undermining the health and well-being of water bodies and freshwater ecosystems is not consistent with the NPS-FM directive or the RMA.
Rivers and streams are connected to and interact with groundwater and lakes and wetlands. All water systems will interconnect and influence each other’s environmental flows and levels. Your regional plan must ensure there are sufficient water levels and environmental flows for all water body types.
Setting precautionary MALF limits is critical as this is the time that the system is most stressed – during hot, low flow conditions – typically during summertime, which can increase water temperatures and encourage algae to grow. Inappropriate allocation limits can cause detrimental impacts to ecosystems if low flows have been pushed past natural ecological limits and water bodies and freshwater ecosystems becomes stressed. The earlier that low flows begin and the longer they last, the greater the impact on ecosystems health. Consider how hydrology calculations (achieving ecological flows) will account for deoxygenation effects at times of low flow as well.
Calculating allocation limits in the past have often been based on current allocation limits and historical records, and each year, water permits are added up to determine the next years allocation limit and as a predictor for future allocation limits. This is not an appropriate way to determine your allocation limits. We expect you to adjust your historical records to forecast for climate change predictions as well. The Ministry for the Environment has published the statistics for each region and those should be used as a starting point (footnote 6).
Often rules are written as a single litre per second units because that is simple. We want to see you develop more advanced approaches to setting take limits, and this should include changing take limits as flows increase and decrease and take rates adjusting to instantaneous flow where monitoring technology allows for this approach. For example, if the water flow is 200 litres per second, then the take limit would be 20 litres per second, but if the water flow is only 100 litres per second, then the take limit would only be 10 litres per second. With this approach, the amount of water taken will vary with the amount of water that is currently flowing in the river or stream which will help maintain the rivers natural flow variability. This ‘stepped’ approach is relatively easy to implement (assuming good allocation records are kept, and usage is maintained) and it avoids the need for flow sharing as flow reduces.
Ideally your precautionary approach will require take limits of 10 percent of the instantaneous flow for regimes harvesting large amounts of water at high flow. For all others, using MALF estimates is more precautionary. This will protect the health and well-being of water bodies and freshwater ecosystems as well as the changes predicted by climate change. The advantage of setting takes based upon a percentage of instantaneous flow is that you maintain a more 'naturalised' hydrograph through its full range, particularly as minimum flow is approached, this avoids running the river dry at minimum flow for extended periods and has an ecological benefit.
We understand that technology for real time monitoring and automatic pump regulators are not available in every instance. However, large allocation takes such as hydro schemes have the infrastructure and often the public interest incentive in place to implement this and improve the public and ecology outcomes of these activities. We want to see you enforce these new management requirements for large take allocations. The take rate for most small pumps can still be worked out based on the size of the pump and diameter of the pump being used, so whether it is a Permitted or consented activity, we expect that water users will know their rate of take and be able to comply with the conditions of their water takes and permitted standards. The requirement to test and certify this is not overly onerous either.
You will need to manage water through a range of other flows to maintain the frequency and magnitude of key flows that are ecologically relevant, such as 3FRE events (3 times the median flow), flood flows and the median flow as ecosystems also rely on those metrics to function. There are limitations to these metrics, and it is increasing being understood that a range of flows are important to ecosystem health, however these more common metrics do provide a place to start. Median flow for example, is an important measure to ensure you are maintaining the variability above and below the natural environmental flow. Ask yourself what your take limits are for MALF, what your take limits are for flood flow and median flow levels, and what your take limits are for 3FRE events? Include those numbers in your regional plan rules and make sure they are measured and monitored.
We want you to identify the cultural flow requirements for all species that are important to hapū and iwi, including the range of flows required for their entire life cycle. Cultural flows are essential to provide for the habitat and biological ques that are important species to Māori such as piharau, kōura, īnanga/atutahi, ngaore (smelt), tuna and kākahi. This includes the ecological flow required for the species entire life cycle, not just during times of harvest. The appropriate range of flow provision will help support the cultural connection to mahinga kai as a compulsory value. However, cultural flows are more than just mahinga kai, many species are taonga and may be in culturally significant sites. Mahinga kai is more than harvest as well and encompasses wider consideration of indigenous freshwater species function within healthy ecosystems. Bathing, swimming and identifying significant places of wai tapu such as tohi will be important to provide for. This will require you to engage with and build trusted relationships with tangata whenua to find out the values and flows that support them, as mātauranga Māori cannot be expected to be freely given.
Footnotes
5. Hayes, J. W. (2023). Review of environmental flow limits for the Wairau River in the proposed Marlborough Environment Plan, and of consent applications for converting Class B to Class A allocations. Prepared for: Nelson-Marlborough Fish and Game Council. Fin & Flow Consulting Report No. F&F2023-1. 64 p.
6. NIWA. (2019). National water allocation statistics for environmental reporting; 2018. Prepared for: Minsitry for the Environment.
How should the NPS-FM be implemented?
Setting environmental flows and levels requires integrated thinking
Environmental flows need to be considered from the starting point of a naturalised flow. We expect you to protect the environmental flows for the whole length of a river, there are no trade-offs, so you cannot take from one part of the river for another. You will need to treat and manage surface and groundwater as the same resource – water, in an integrated system. Groundwater takes can cumulatively have a significant stream depletion effect on surface water, particularly spring fed water bodies, so you need to account for both (especially where there is a ‘moderate’ or greater degree of hydraulic connection between groundwater and surface water). Interconnected water body types need to be managed together.
There are key features of flow regimes and their environmental functions that should be integrated into your thinking to sustain freshwater values (some considerations are listed below and outlined in the report by Hayes (2023) (footnote 7):
Components of the hydrograph and their environmental functions
Ecologically relevant flow statistics
Space and food as flow-limiting factors for fish
Flow variability
The transport capacity of rivers – as it relates to life-supporting capacity and ecosystem health
The minimum flow allocation rate: how they interact to affect instream life
In addition, you will need to think about how your regional plan could drive land use change in catchments to improve or restore flows and increase resilience for ecosystems and communities. Land use change can have a dramatic effect on catchment yield. Studies (footnote 8) demonstrate, for example, that tussock communities have a greater catchment yield over pasture or forestry. Decreasing catchment yield will impact both people and ecosystems, because the total amount of water available to be allocated will be reduced. This may mean that minimum flows are reached more often and the adverse effects from previously set allocations may become unacceptable.
Plans must work in concert to manage vegetation alongside setting environmental flows. For example, wetlands and forest restoration can help keep water in the landscape, reducing hydrograph peaks and thus limiting flood damage. Restoring vegetation around waterways can also mean irrigators do not have to take as much water as land does not dry out as quickly. Making room for rivers can help to restore aquifer recharge, meaning groundwater resource are more reliable in summer and surface water takes can be reduced.
You will also need to consider the effects of climate change and changing pattern of use such as reduced snow melt, higher demand for water in summer months and in areas that traditionally did not need water irrigation in the past. This will have an impact on catchment yield.
Footnotes
7. Hayes, J. W. (2023). Review of environmental flow limits for the Wairau River in the proposed Marlborough Environment Plan, and of consent applications for converting Class B to Class A allocations. Prepared for: Nelson-Marlborough Fish and Game Council. Fin & Flow Consulting Report No. F&F2023-1. 64 p.
8. Mark, A. F. And Dickinson, K. J. M. (2008). Maximizing water yield with indigenous non-forest vegetation: a New Zealand perspective. Frontiers in Ecology and the Environment. Vol. 6, Issue 1, 25 – 34. (Online: https://doi.org/10.1890/060130), https://esajournals.onlinelibrary.wiley.com/doi/abs/10.1890/060130.
Restrict water takes before environmental flows are at risk
It is unclear the extent of water allocated in Aotearoa New Zealand. There is a lack of water allocation frameworks implemented across the country to manage takes, including permitted water takes and small tributaries, both of which help to make up the total water levels in a system.
Allocation limits need to be set at levels that do not risk breaking points. Precaution is required when setting limits. This means stopping water from being taken out of rivers and groundwater before water quality and quantity issues occur. It is extremely difficult to return water to a river once it has been allocated. Allocating a volume of water equivalent to 30% of MALF has been common practice. Ecosystems may survive this for a short time, as they are naturally resilient, but like the human body, the longer periods of time it is under stress, the more impact it will have on the system over time.
Although it can be difficult to definitively draw a line at what level is considered safe for ecological flows – we know that the more water taken, the greater the risk of impact on species success. You should also treat water diversion and low flow barriers that will dewater local rivers the same as abstraction. The NPS-FM requires that you prioritise water bodies and ecosystem health. The marginal differences in water take limits should always act on the side of caution and for the wai first.
Allocation limits require an understanding of local context
All water bodies are different and the values and outcomes that the community seek for their rivers, lakes, groundwater, and estuaries will also be unique. You will need to set environmental flows and levels that can meet a diverse range of ecological, cultural, recreation and economic needs – but not all needs will be equally weighted.
There are online tools available to model MALF. However, models are not a true representation of what the natural system is doing or what the effect of decisions made about flow levels will have on species and their habitat. The interaction between ground and surface water and connections between water bodies are as complex as the species interactions within those water bodies. You will need to undertake local studies of your catchment to understand the local intricacies of your water body interactions such as bioenergetic relationships to flow.
When undertaking these studies, be conscious that it may take longer than you would expect for groundwater and surface water interactions to stabilise. Simply halting abstraction for a few hours or days may not re-create naturalised flow conditions. In rivers where surface flows go to ground, the water on the surface is often linked with the groundwater table. When groundwater is depleted because of abstraction of surface flows, they may need to be recharged before the river begins behaving as it should.
There are limits to using IFIM to set minimum flow levels – use the Presumptive Standard.
You should not rely on hydraulic habitat modelling on its own. Local decision making will require in-depth studies for intermittent (and some ephemeral) rivers. We know that surface flows are greatly influenced by groundwater levels and that the relationship is not always constant. The decisions you make about how environmental flows and levels are set should focus on the outcomes you want to see so that the ecological and other values set by your community can be achieved.
There are a limited number of methods that are used to determine how minimum flow levels are set such as the Instream Flow Incremental Methodology (IFIM). In New Zealand, there has been a heavy reliance on IFIM, however there are significant limitations to this method that need to be realised, particularly relating to different life cycles of fish species and flow dependent species. It also does not consider species interactions and food availability in the system (footnote 9). Although IFIM is cheap and provides a tidy percentage that appears easy to understand, it is poor in approximating habitat quantity and habitat quality. This leaves a lot of room for interpretation and can create bias in how it is applied. IFIM can be used successfully, but you need to understand and account for its shortfalls (footnote 10).
We want to see the Presumptive Standard (footnote 11) approach used as the method to set your environmental flow when site-specific environmental flow determinations cannot yet be applied. This means the allowable rate of water take for a given day is set as a percentage (e.g. 10%) of the naturalised flow for that day. This rate reduces as the natural flow reduces and is applied consistently across the entire flow range.
Footnotes
9. Hudson, H., Byrom, A. E. And Chadderton, W. L. (2003). Department of Conservation: A critique of IFIM – instream habitat simulation in the New Zealand context. Science for Conservarion 231. Wellington, New Zealand.
10. Hudson, H., Byrom, A. E. And Chadderton, W. L. (2003). Department of Conservation: A critique of IFIM – instream habitat simulation in the New Zealand context. Science for Conservarion 231. Wellington, New Zealand.
11. Richter, B.D.; Davis, M. M.; Apse, C. And Konrad, C. (2012). Short Communication: A Presmptive Standard for Environmental Flow Protection. River reserve and application, River Res. Applic, 28: 1312 – 1321. DOI: 10.1002/rra.1511
Allocate less water to improve certainty and security.
A greater water take limit does not mean greater certainty and water security. In fact, the opposite is true. The higher your allocation limit i.e. 30% allocation instead of 20% allocation, the sooner you will need to turn off the pump because you will reach your limit quicker. Also, you will have to leave that pump off longer, because you will need to wait a longer period for environmental flows and levels to be restored.
Resource consents typically state that when the levels become too low, then you must stop taking water. But the greatest level of certainty for continued business access to water, is water supply 100% of the time. If you are at risk of turning off the pump then there is uncertainty, and the higher the allocation limit, the lower the security of supply.
You will need to make decisions on how you will manage consented use and actual use of water allocation. If the actual use is lower than the consented take, you should not consent more if people are not using it all, and those takes should only allow for the activity that has been consented. This approach will assist in phasing out over-allocation in a catchment and avoiding over-allocation in the future, by consenting less when there is a review of less actual water used than consented. During reviews or when consenting new takes, you will need to assess the effects of the water take and the effects of the use for that water take, (not just the volume of water) when making decisions to grant them.
The longer and more frequently stressed the water body is (i.e., the system is subjected to low flows and levels over an extended period), the greater it will impact the health and well-being of the water body and freshwater ecosystem. You must be bold, as the NPS-FM directs that you make sure your take limits reflect the needs of the water body and freshwater ecosystem first – not the historical abstraction that has previously been allocated.
You should allocate less water to provide more certainty for water users and to protect instream values for water bodies and ecosystem health.
Prioritise public use over private water allocation
Public water needs to be prioritised over private use. For example, once enough water has been allocated for water bodies themselves and ecological health, use for public health and wellbeing such as swimming should be allocated before private water allocation for commercial use.
Community supplies will need to be carefully considered, as not all public water takes are used solely for drinking water. Other activities such as filling troughs, dairy shed use, irrigation for orcharding like kiwi fruit and watering gardens are often taken from this water supply take. When considering water quantity decisions, particularly allocation, you will need to consider links to the end use of water.
We want to see hydro peaking restricted or prohibited in your regional plan. Hydro power stations release pulses of water to increase hydroelectric power production profitability, resulting in rapid and frequent, short-term fluctuations in water flow and water levels down and upstream of the plant (footnote 12). This changes the natural flow variation in rivers and has far-reaching effects on river environments, aquatic and terrestrial species, and the safety of people and communities, such as recreational users who may not know the activity is occurring.
Footnotes
12. Bejarano, M. D.; Jansson, R. And Nilsson, C. (2017). The effects of hydropeaking on riverine plants: a review. Department of Ecology and Environmental Science, Landscape Ecology Group. Umeå University, SE- 901 87, Umeå Sweden.
Avoid new dams and introduce residual and flushing flows to existing dams
We want to see new dams avoided and all existing dams introduce residual and flushing flows that will protect the health and well-being of water bodies and freshwater ecosystems. Ultimately, removing dams could have widespread ecological, recreational and cultural benefits to restoring ecosystem health.
Dams have been constructed across Aotearoa New Zealand and many were consented long before there was a strong framework to protect freshwater matters such as environmental flows and biodiversity. The scale and impact of these structures have long lasting and severe impacts on freshwater ecosystem health. Much of this impact results in irreversible loss of species and ecosystems (footnote 13).
Many native fish species such as tuna and īnanga (whitebait) are diadromous and need access up and down river systems to complete their lifecycle. Hydro dams are often dangerous places for fish to navigate as penstocks and the turbines can kill species as they try to move through them – even when alternate fish passage is provided.
Instead of looking to the past to build or maintain dams (footnote 14), think to the future and what alternative measures can be put in place to support freshwater management and allocation. For example, rather than damming more water for land use activities, promote the right type of land uses in the right type of place by re-allocating water from large inefficient users to more suitable activities for the region they are in. This could include promoting cropping in wetter areas and restricting dairying in drylands.
Footnotes
13. Joy, M. and Foote, K. (2017). Dam the Dams. Online: https://www.researchgate.net/publication/321094881_Damn_the_dams
14. Bladder storage units generally have a 10 year warranty but should only be used on occasion
Use high flow only takes for offline storage options
‘Offline’ water storage options are a good way for consent holders to plan for access to water takes during low flow periods. Like water tanks for drinking water, water access for other activities can be safeguarded for consistency and certainty, if storage solutions are invested in. Options include tanks, dams, ponds (or more recent technology like bladder storage) (footnote 15) to draw down a take allocation and secure it more independent of the water body state.
Best practice draws water during ‘high-flow takes’, also known as ‘peak-flow takes’ which refers to takes only allowed above median flows or higher. This means people do not need to dam waterways or risk drawing water when water levels are low, but demand is high or consistently required for activities. There is some risk that takes during high flow will result in murkier, disturbed water with more sediment in ponds, but sediment removal can be planned for, and it is still a better option than taking at low flows. Takes during low flows has impacts on freshwater, its natural character and the freshwater species that depend upon it.
We do not expect all ‘peak-flow’ water to be taken off the top and stored, as these peaks are still an important part of the way rivers need to flush out sediment and support natural processes to protect natural form and character. For example, we need to ensure summer fresh events provide their ecological benefits and are not ‘skimmed’ by high flow takes. We still expect an allocation limit on the number above median flow takes per catchment.
Along with the ecological benefits of only taking water at high flow for storage, it can provide business certainty for water supply, independent of low flow situations. Some regulators manage storage activities as a Permitted activity, but this is often attached to a large number of conditions to meet this activity status. It would be better managed as a Controlled activity to better regulate how each situation is assessed and to control the way water storage is undertaken to meet water take allocations and limits. For example, takes may be restricted during certain months and a consent makes this more clearly enforceable. A consent document also provides an additional asset for the owner to on-sell. Engineering specific river-height take structures may require a significant in-stream structure, such as a weir on the bed and bank. Real-time monitoring and compliance is still new but provides an opportunity to think differently about how water takes are allocated and managed for all parties.
Footnotes
15. Bladder storage units generally have a 10 year warranty but should only be used on occasion
Root stock survival water allocation must be an emergency-type take
Access to water resources for root stock survival is critical for industry. If there is no water, and plants die, this can have huge economic impacts, however businesses must prepare for dry conditions.
We want to see water takes for root stock survival regulated as a Discretionary activity. A condition of granting should be evidence of pre-prepared actions to store water, rather than rely on an allocation below minimum flow. Storage may be a prerequisite for granting a root stock survival takes. This needs to come out of existing allocations and it should only be for emergency-type takes at times of greatest impact – it is not to support production augmentation or growth. Volumes to determine what ‘survival’ means will need to be well researched, agreed in advance and regulated. Volumes should also be relatively small and require very efficient and bespoke application for each situation.
A root stock survival scenario is foreseeable and prudent businesses should be reasonably able to plan for the recurrence interval. Businesses must take due diligence to avoid a need for this type of take. Resource consents should only be granted on exceptional circumstances and with proof of adequate business planning, similar to town businesses supply agreements with town water suppliers.
Use evidence to make good decisions for environmental flows
The NPS-FM requires you to use the best information available to set environmental flows and levels and take limits. This means you cannot use the numbers currently in your plan, or numbers that simply reflect current takes as a default. You must use the best information available which may include river specific studies, or aggregated research reviews.
You will need to undertake local studies of your catchment to understand the intricacies of your water body interactions such as bioenergetic relationships to flow. We expect your studies to include smaller tributaries.
It is critical to understand and document local information through regional specific studies to ensure that low flow is alleviated as soon as possible. Although most councils have aspects of collecting data set up as part of regular monitoring, many do not have the extent of data required to make good decisions and achieve the purpose of the accounting systems outlined in Clause 3.29. For example, although the draft NES Flows states you do not have to measure permitted takes, it is often those smaller takes, particularly on smaller streams, that cumulatively, can have significant impacts on the environmental flow and levels of that ecosystem and its interconnected water system.
If you do not have sufficient data about the total amount of water taken, then there is likely a large portion of flow that is not accounted for in the water allocation framework. Remember the plan cannot allow water to be taken below a minimum flow – even for a permitted activity. To prevent flows falling below minimum flows and levels, you will need to implement a one-to-one flow sharing regime (footnote 16) by requiring each user to reduce their rate of take on a pro rata basis or set up a rostering system whereby groups of users have access to the common water resource at different times. This will need to indicate when flows reach the sum of the minimum flow or level by determining the total volume of water allocated through current resource consents and Permitted activities for the relevant surface water body. You should establish a water user group to assist in developing suitable restrictions to implement the flow sharing regime to make sure it is fit-for-purpose.
A common shortfall in calculating flow regimes is to miss accounting for Permitted water takes. Every water take, whether it is consented for not, for example regular household use and small private water supply takes are also included in the total take – so make sure that you know what water takes are occurring, at all times, and make provision for that in your allocation framework.
Footnotes
16. Biggs, B. J.F., Ibbitt, R. P., Jowett, I. G. (2008) Determination of flow regimes for protection of in-river values in New Zealand: and overview. Ecohydrology&Hydrobiology. Vol 8, No 1, 17 – 29. DOI: 10.2478/v10104-009-0002-3
How we know the NPS-FM is being achieved
The natural flow variability of water will be restored to water bodies across Aotearoa New Zealand. This means that enough flow is available for the natural character of that system to freely express itself, while ensuring that ecological needs are also being meet. Your regional plans will use best information available to set limits in your plans and these limits will achieve the outcomes for environmental flows and levels. Flow connects all aspects of freshwater management, and this will be at the forefront of how decisions are made on take limits.
Implementation Toolbox
The toolbox will continue to be developed as new information becomes available:
Tools: are helpful diagrams, processes, or ways to support how you should implement the NPS-FM.
Examples: provide text suggestions to help draft objectives (values and environmental outcomes), policies, and rules (limits) in your regional plans, including how monitoring could be achieved. It includes examples of how attributes and base line states, target attribute states, environmental flows and levels, and other criteria, where appropriate, can be written or presented to help achieve environmental outcomes.
Case studies: illustrate where the NPS-FM has been well applied (or not) throughout the country and provides national or international lessons to help implement the NPS-FM.
Evidence: provides relevant case law to support how the NPS-FM must be applied.
Resources: provide links to supporting literature and best information available to implement the NPS-FM.
Tools
[When available]
Cultural Tool
https://www.culturalflows.co.nz/
Examples
[When available]
Case studies
[When available]
Evidence
[When available]
Resources
Hayes, J. W. (2023). Review of environmental flow limits for the Wairau River in the proposed Marlborough Environment Plan, and of consent applications for converting Class B to Class A allocations. Fin & Flow Consulting Report No. F&F2023-1. 64 p.
Hudson, H., Byrom, A. E. And Chadderton, W. L. (2003). Department of Conservation: A critique of IFIM – instream habitat simulation in the New Zealand context. Science for Conservarion 231. Wellington, New Zealand.
Richter, B.D.; Davis, M. M.; Apse, C. And Konrad, C. (2012). Short Communication: A Presmptive Standard for Environmental Flow Protection. River reserve and application, River Res. Applic, 28: 1312 – 1321. DOI: 10.1002/rra.1511
NIWA. (2019). National water allocation statistics for environmental reporting; 2018. Prepared for: Ministry for the Environment.
Fish and Game, Forest and Bird and Choose Clean Water have written this practice note to communicate their expectation on how regional councils should implement the National Policy Statement for Freshwater Management 2020 (NPS-FM) into their regional plans. This is one in a series of practices notes which have been prepared on various topics relating to NPS-FM implementation.
