Improving the protection of drinking-water sources

We believe that the zoned approach proposed in the discussion document should be clearly identified as a baseline protective measure with an expectation that detailed risk assessments will be conducted wherever possible. Specifically, we would recommend that catchment risk assessments that account for both local hydrogeology and public health risk should be mandatory for suppliers working under S2 and S3 source water rules stipulated by Taumata Arowai. It should also be made very clear that an integrated approach is expected as part of Te Mana o Te Wai as stated in the NPS-FW “Local authorities must take an integrated management approach to freshwater management in accordance with the principle of ki uta ki tai (‘from the mountains to the sea’)”(s3.5.1).
In practical terms, we are concerned that for many larger supplies separating into three areas, rather than taking an integrated approach, may lead to an under or over estimation of actual risks. For example, a large contamination event in SWRMA3 may be a bigger risk than a smaller event in SWRMA1. Or a permitted activity may happen just outside the ‘zone’ and still be a risk. Each activity should be evaluated from a ‘whole of catchment’ risk perspective – is 501m different than 499m from an intake? A discharge prohibited at 499m would be allowable at 501m despite no difference in risk? Within SWRMA3 consideration needs to be taken for any potential draw down effects, as seen in Havelock North. If a water supply is over abstracted there is an increased risk from zone 1, and to a lesser extent, zone 2, to effective pull contaminants through into supply. Again, this points to a real need for a case-by-case initial assessment to be made on top of the stated baseline requirements. The Australian framework whereby different land uses are prioritised in the area surrounding a drinking water source provides a useful tool in clarifying the overall management strategy across a catchment .
As stated in the discussion document, the three at-risk area approach is supported by international agencies as quoted in the report, but these other agencies also note that this technique is a simplification exercise that does not reflect supply complexity . The stated zone areas are also substantially reduced as compared to the UK and US comparisons highlighted in the report. The reason for the reduction seems to be a “pragmatic” response to accommodate smaller drinking water supply but this is not matched with an increasing area of protection for larger supplies . At minimum, a risk-management approach, in line with the source water protection plans required by Taumata Arowai, should be incorporated into this very basic protection framework.

What is the advice if there is less than 8 hours travel to the intake, ads may be the case in small catchments.
There is no evidence presented that 2.5km should be the maximum distance. An evidence-based approach should be applied. PDP (2018)3 only suggests consideration should be given to existing activities. This is not a precautionary or a risk management approach.
It is unclear why the median flows are used to delineate source protection zones. A risk-based approach would include the circumstances when the water source is most at risk e.g., high flows, low flow, high abstraction rates etc.

‒ Should SWRMA for all aquifers be bespoke so their unique features, depth and overall vulnerability can be considered?
Yes. There is evidence in the literature that the geology, lithology of an aquifer and its overlying vadose zone and soils will play a role in the risk of contamination occurring. Assessments of aquifers used for drinking water is a must.

It is appropriate that for drinking water abstraction a wider setback distance is used. ESR does not think these differing setbacks will cause confusion because protection of source water for drinking is a different objective. Stock Exclusion Regulations with the 3 m setback are for reduction of contamination of waterways by stock. There are circumstances in which Stock Exclusion Regulations don’t apply e.g.,
• if there is fencing.
• stock need to access a dedicated bridge or culvert,
• stock are actively supervised as driven across the lake or wide river and it’s not more than twice a month.
• It’s too difficult to install a dedicated bridge or culvert on a highly mobile riverbed and stock are actively supervised as driven across the lake or wide river.
These conditions are not necessarily appropriate exclusions when applied to drinking water extraction and potential for contamination.

‒ Do you agree that a 5-metre radius around a source water bore gives enough protection? Why or why not?

With much of the change in the water sector being driven by an event linked to potential contamination of a bore head, a conservative approach should be considered. Setting zones should be evidence based. Pragmatism is not in keeping with a risk management approach. No evidence is presented in PDP 20183 to support a 5m zone, just a statement that 30 m may be impracticable. There will be many different interpretations of “impractical”. For bore head protection a recommendation that new bores are developed with a 10m protection zone may increase the degree of safety over time while still allowing current bores to operate with the currently more achievable protection radius of 5m.

‒ If not, what alternative would you suggest?
Ideally a whole of catchment integrated approach will be used that factors in the potential public health risk of a contamination event. However, if a standard set-back is to be used then a 10m minimum distance should established for all new source water bores.

To avoid inconsistent approaches, litigation and delays (as mentioned in the RIS), bespoke, or case-by-case, methodologies should only be applied in very specific circumstances such as complex interlinked systems.
Having said this, standard methodology and modelling approaches for risk assessments should be developed urgently. The use of locally specific hydrogeological data and potential hazards will provide more protection than a generic baseline zone and therefore should be explicitly expected, particularly for supplies working under S2 and S3 assurance rules.

As a minimum a source-water protection zones must be consistent with the national direction, or more precautionary. At the time of establishment by the regional council, the water source protection may not have assumed the importance that is now required following the Havelock North outbreak and investigations. With the inclusion of a new category of very small suppliers within the Water Services Act, there are possibly new supplies that won’t have been included in previous planning exercises. This will need to be addressed. Furthermore, allowing historical processes for determining water protection zones would lead to inconsistencies and inequities with lesser protection for some communities. The development of accepted standard techniques and models would assist in ensuring both location specific risk analysis and regional uniformity.

Yes, it is essential to balance the enabling philosophy of the RMA with the precautionary approach required for managing public health risk. Water suppliers and Regional council staff will have a variety of experience and knowledge, with those in smaller areas likely to have less expertise at hand. Providing national direction reduces litigation with its inherent delays and costs. A national direction provides clarity and certainty and improves consistency in decision making.

‒ If so, what activities should it address?
• Any activities that elicit contaminants that cannot be removed by the drinking water treatment process (treatment and disinfection) defined under the Taumata Arowai acceptable solutions. Or contaminants that may react with treatment processes to produce harmful by-products (e.g., disinfection by-products)
• Activities that affect flow, or quantity (for groundwater) as this will impact other users and estimates of contaminate concentrations from other sources
• Discharge of recycled water
• Discharge, runoff and ponding of effluent
• The activities need to be clearly focussed on the potential for contamination of source water, including cumulative effects and the consequences of emergencies e.g., flooding, fire and climate change
• The activity provides a pathway for contaminants to enter the water e.g., construction of dams, earthworks drilling, excavations e.g., for ponds, unlined ponds which are designed to seal over time by the accumulation of sludge e.g., waste stabilisation ponds are sometimes constructed in the way
• Desludging of waste stabilisation ponds,
• Composting
• Activities that produce contaminants that persist in the water system for extended periods
• Activities that have the potential to significantly alter the biodiversity of the water habitat such that would impact water quality or introduce new organisms through environmental alteration

‒ How restrictive should controls be in SWRMA 1, for resource users other than water suppliers?
Drinking water protection should be a priority and the requirements to protect the source water should have greater hierarchy that other resource users. NPS-FM (s31.21) states that the first right to water is water itself. The RMA provides an effects management hierarchy, permitted activity should:
• Avoid adverse effects first
• Then mitigate any adverse effects,
• Offset adverse effects,
• Provide aquatic compensation and then,
• Avoid the activity.
Drinking water provides an important conduit between environmental and human health and as such restrictive controls appropriate to risk are warranted. Restrictive controls provide certainty, avoid litigation and attendant delays. With source waters it is now a legal requirement to adopt the principles of Te Mana o Te Wai. The current collective understanding of this is that source water protection is paramount to protecting water and human health, this can only be practically achieved through strong NES-DW guidance which promotes good decision making under the RMA. The intent of the RMA is to protect environmental health, not human health, and so protections NES-DW must consider potential human health impacts carefully and provide a clear framework that enables councils to act prevent contaminants entering the water supply, particularly for larger populations.

‒ Are there any activities you believe should be fully prohibited in this area? \
In line with earlier comments, each source and supply should be considered on a case-by-case basis. Risks between groundwater and surface water will be quite different and require different management. Overall, consideration should be given to the following factors:
• Using or storing hazardous substances including chemicals, radiation sources, explosives in bulk volumes
• Any activities requiring physical containment facilities at PC2 level or above
• Abattoirs or other activities dealing with carcass processing, offal pits
• Crematoriums
• Landfills
• On-site wastewater facilities, faecal compositing
• Intensive stock holding areas or pens

Yes. The RMA is an enabling act, with a duty to avoid, mitigate or remedy effects, as highlighted in the NPS-FM effects management hierarchy. Cumulative effects can be difficult to assess and some may not be apparent for some time e.g., nitrates in Canterbury groundwater. There can be a high level of uncertainty around the effectiveness of mitigation measures, especially as they won’t take into account the impact of cumulative effects, particularly over the time of a consent, which may be 25-30 years.
A precautionary principle should be applied to protect health with national direction on activities, otherwise there will be inconsistent decisions made about what is acceptable in SWRMA2. It also provides certainty for applicants and reduces the potential for litigation. PDP (20183) state that there should be careful control of all activities that contribute non-point source contamination sources in Zone 2.

‒ If so, what activities should it address?
See comments from earlier but broadly it should address activities which can contaminate the drinking water source, provide a pathway for contamination (direct or indirect) or adverse effects from an emergency, accident, climate change, where identification of the adverse effects, attenuation and mitigation of those adverse effects is unlikely to occur within the travel time. Cumulative effects also need to be addressed e.g., on-site wastewater systems within an area, land use changes. Nonpoint sources such as irrigation and stock numbers, should also be carefully controlled (PDP 20183). Consideration needs to be given to emerging contaminants including organic contaminants and microplastic, the framework needs to provide sufficient flexibility to include future developments and understandings of risk.

See comments to previous questions but broadly protections should be in place that prevent any contaminant entering the drinking water supply that cannot be mitigated/eliminated by treatment processes defined under an “acceptable solution” including viruses. It is important to clearly state that the level of treatment is aligned to acceptable solutions, as anything can be treated to remove any contaminant, at a price. This is inequitable as it is not the polluter who pays.
Any chemicals with a potential to accumulate over time in the water system e.g., nitrates, pesticides.
Storage of large volumes of chemicals that could lead to a contamination event e.g., pesticides or fuel could leach into groundwater, or use of timber treatment chemicals which can runoff site or leach through soils.

There is a lack of detail about emergencies or effects of climate change (i.e., a long-term change) in SWRMA 3 and what protections need to be in place to mitigate the impact of these events.

‒ What is your view on requiring unused bores to be decommissioned?
It is essential to decommission unused bores to allow prioritisation of drinking water sources where they exist without undue influence on other activities.

‒ Should bores of poor quality be required to be upgraded or decommissioned? What timeframe might be reasonable to do this?
Yes, this should be required as a co-ordinated activity with source water planning on the same timeframe as required by Taumata Arowai.

A combined approach is required across NES-DW and NPSFM2020. Careful consideration needs to be made as to the appropriateness of using vulnerable aquifers for drinking water source. The approach taken should include tangata whenua and ensure any approaches uphold Te tiriti and Te mana o te wai.

Details provided in previous questions

Can be numerous – all risks should be identified within the SWRMA and a risk assessment performed on each. Some of these have been outlined in sections above.

A few examples -
• Discharge of any untreated effluent (wastewater overflows (septic and municipal), tradewaste, industrial waste etc)
• Overflow from oxidation ponds
• Offal pits, effluent ponds
• Chemical stores within the catchment
• Run-off from farms after heavy rain events (e.g., Walkerton, Havelock North)
• Insufficient water (drought, other users)
• Intensive stock holding areas
• Landfills and landfill leachates
• Highly combustible materials that may result in firefighting runoff entering the water supply or those that may release pollutants when burning such as arsenic, plastics, heavy metals etc.
• Timber treatment yards
• Petrol stations and airports
• Location in relation to contaminated sites
• Changes to aquifer structure – water table fluctuations
• Water table increase from flood events could lead to mounding of supplies leading to changes in flow through network
• Cracks/breaks in pipework
• Infiltration into network of sediment/silt

All activities with some potential to affect source water (for drinking water) should undertake emergency response planning and risk assessment. Contingency plans are required under the RMA. The precautionary principle should be applied as the worst outbreaks are usually an unexpected combination of failures and events. Risk can change over time as activities change, therefore an up-to-date response or contingency plan is an important on-going management tool.

Yes, but it may overwhelm small water suppliers so some assistance may be required.

Yes – NES-DW should apply to all registered water supplies. Equity is important. Smaller communities may be more at risk and have less resources. If a risk-based approach for larger supplies (those applying S2 and S3 assurance rules) is applied, then actions can be proportionate to the size and complexity of the DW supply. The current zones would provide an easy-to-use standard for small suppliers under the S1 assurance rules.

Overall, ESR strongly supports the revision of the NES to improve protections for drinking water sources. We agree that amending the NES-DW is the correct approach to ensure that it specifically addresses drinking water and adequately addresses the issues which are complex and very technical. The NES Freshwater Management is too broad to address these issues and so the revision of the NES-DW is appropriate and valid.
We also agree on the timing to support Source Water Risk Management Plans and Regional Plans.

There are still some overall concerns including:
• Quantity protection and responses as low flows can rapidly increase contamination
• Insufficient information and guidance around cumulative effects such as land application of waste; fertiliser addition, pesticides/herbicides.
• Ensuring that the NES-DW align with Taumata Arowai source rules, e.g., the proposed “Acceptable Solution for Spring and Bore Water” stipulates certain activities such as sewage disposal are not permitted within 50m of a bore head, this doesn’t obviously align with the proposed SWRMA2 which is 1 year travel time or 2.5km.
• Similarly, it is key that the NES-DW align with NES for recreational water.
• While NPS-FM requires assessment of cumulative effects there is not very much direction. How long for example would it take to establish a trend? The issue with cumulative effects is that once the trend is recognised it can be difficult to identify the source of the problem if there are several consents or activities in the area. This could significantly impede the Council’s ability to intervene. What level of evidence would be needed to satisfy a consent holder that the source had been identified and they would be required to take action or stop the activity?
• The definition of a water supplier is defined under the Water Services Act (i.e., a supply serving more than one household), what protections are in place for individual household supplies?
• What is the process if a water supplier needs to identify a new source e.g., climate change may change rainfall patterns?
• What mechanisms are available and/or needed for protecting waters that have been identified as potential future drinking water sources to prevent contamination prior to them being designated as an actual drinking water source?
• Critically, there is a need to make it clear that ongoing assessment and monitoring is necessary, beyond which may be legally required to comply with Source Water Assurance Rules. In previous iterations of the regulations there has been a lack of the ongoing assessment of a drinking water supply. This is especially pertinent in the current climate change scenario. Conditions change over time, for example, amount of water abstracted which will influence the potential risk of contaminant presence. Or, drought followed by flood, which again increases the risk of contamination.
• There is a need to also recognise the importance of assessing the health of a water source as it is biological processes within the wider water ecosystem that can reduce the risk of contamination. This is also a remit of the NPSFM 2020, maintain the mauri of wai. Consideration needs to be explicitly made to the importance of the health of system itself.