Wastewater 5 Options v1

Wastewater Options Q&As

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Wastewater Options Q&As

Information about the options for wastewater management from the treatment plant in Banks Street to the marine outfall pipe in the Bay.

For information on the project to reduce wastewater being discharged into our rivers and onto people's properties during rain events - see DrainWise 

Q&As about the wastewater treatment plant, the options and costs, the treatment plant upgrade and the discharge into the bay.

The wastewater treatment plant

Why is more work required on the treatment plant?

The 2010 upgrade was the first stage to improving the treatment plant discharge to bring it up to modern standards. The resource consent for the treatment plant requires additional improvement to be made over time. Even after the previous upgrade, Gisborne’s wastewater treatment system was bench marked as being below that of most comparable councils. Community expectations and environmental standards are also becoming more stringent over time. 

Do we have to spend money now or can it be delayed?

The present discharge complies with stage 1 of the resource consent. It does not comply with the water quality standards that are specified in the consent, which come into force once the preferred long term wastewater management option is implemented. While a number of important dates are referred to in the consent, the long term wastewater management option essentially requires to be implemented by 2020. If this is not done, then Council will not be compliant with the resource consent.

Why can't we discharge the wastewater to land?

At this time, the treatment plant has a sea outfall and the cost of changing that to a land disposal system is significant and we would need to find suitable land that can take the large volume of wastewater for the long term. However, Council is looking at alternative use and disposal options, with the aim of ultimately directing the wastewater elsewhere. An option is to treat the wastewater to a level where the water can be used for irrigation or other processes and then dispose of the solid material to land. This is called “Alternative Use and Disposal” and is required to be considered under our resource consent.

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The options and costs

Why are the options so expensive?

Wastewater treatment is a large and complex process. We're dealing with the whole city’s wastewater flow – about the volume of 5 Olympic size swimming pools each day. It takes land and large engineered systems to treat wastewater.

Option 1 is the minimum under Council’s current resource consent in terms of achieving wastewater quality standards. It does not achieve loading rate conditions, which Option 2 achieves. Council also has to undertake best endeavours to find alternate use and disposal options and achieve cultural outcomes envisaged in the consent. Iwi representatives consider Options 3, 4 and 5 go towards achieving these aspects.

What are the main differences between the 5 options?

The difference is mainly the level of treatment that occurs. The investment in potential alternate use and disposal, cultural aspects of the consent and the cost of that additional treatment. Each of the options has an added stage of treatment that incrementally improve the quality of the discharge.

What if the district can't afford it?

 Aspects of affordability do not remove the water quality conditions in the consent. As a minimum the consent still requires Option 2 to be implemented as stage 2, if all consent conditions related to water quality are to be complied with. 

Are ratepayers absorbing the full cost?

At present no alternative sources of funding have been found for the wastewater infrastructure, and therefore the costs have been expressed on a per household basis. The costs are likely to be borne by all households in the city that are connected or have the ability to connect into the public wastewater system. Both ratepayers and tenants are likely to be affected on account of transferal of costs onto members of the community that rent accommodation. Alternate sources of funding are being investigated.

Why are costs included?

The survey is about finding out which option is supported by the community, in the context of costs, so we can gauge the community’s willingness to pay for wastewater infrastructure. The reason the costs have been included is so that the community makes an informed decision when filling out the survey. The long term plan process will take into account affordability constraints in implementation of that option. 

Are the costs operational?

The costs include operational and capital costs. 

Are you recovering the capital set up?

If so, what would be the payback period? What proportion is annual running costs and maintenance?

The cost is the additional cost for the upgrade option (it does not include current wastewater treatment costs, which are already paid for through rates). It was calculated on a ‘per-connection to the wastewater system’ basis. This was seen to best reflect the cost implication per household. The cost will be funded by ratepayers through the rates or indirectly by tenants through rental costs, unless alternative non-ratepayer funding is secured for the upgrade. Capital and operational costs (including new assets and renewals, debt repayment and inflation) were calculated out over 50 years. The average of this gives us cost per connection to the wastewater system. To calculate the average annual cost we used the number of total connections to the treatment plant (domestic and commercial) which was 15,278. The loan repayment term was 20 years. The proportion of maintenance and running costs varies depending on the option. Operational costs (running costs and maintenance) comprise between 60% and 75% of the annual cost.

Is the cost additional to what we already pay?

Yes. There is an annual increase in rates, and the costs of stage 2 of the wastewater consent will be included within future rates increases.

Can the options be a staged plan over a number of years?

The choices are not mutually exclusive, each option essentially builds on the previous one. A staging plan can be considered by Council, and has formed part of previous discussions. However, staging would likely require a variation to the consent.

What is the pay back period?

What proportion is annual running costs and maintenance? 

The cost is the additional cost for the upgrade option (it does not include current wastewater treatment costs, which are already paid for through rates). It was calculated on a ‘per-connection to the wastewater system’ basis. This was seen to best reflect the cost implication per household. The cost will be funded by ratepayers through the rates or indirectly by tenants through rental costs, unless alternative non-ratepayer funding is secured for the upgrade. Capital and operational costs (including new assets and renewals, debt repayment and inflation) were calculated out over 50 years. The average of this gives us cost per connection to the wastewater system. To calculate the average annual cost we used the number of total connections to the treatment plant (domestic and commercial) which was 15,278. The loan repayment term was 20 years. The proportion of maintenance and running costs varies depending on the option. Operational costs (running costs and maintenance) comprise between 60% and 75% of the annual cost.

After the upgrade will the bay always have great water quality?

Do the options solve all the water quality problems in the bay? 

The water quality in the bay is generally good most of the time and the treatment plant discharge isn’t the only cause of poor water quality in the bay.  The beaches are most affected by water from the city’s rivers. When warning signs are erected at the city beach, it's usually as a result of heavy rainfall and runoff from urban and rural areas and overflows if the rainfall is very intense. Improving the performance of the treatment plant will improve the overall water quality in the bay and reduce the risk of bacteria and viruses that affect swimming, surfing and shellfish in the Bay.  However, it won’t eliminate water quality problems entirely – it's impossible to prevent stormwater runoff from urban areas going to the Bay and this runoff carries some pollutants. At the same time, agricultural pollution also reaches the city’s rivers and eventually the sea and beaches.

Has this been done anywhere else?

There's a large number of NZ councils that have, or are currently, considering wetlands and / or land disposal options, including Ashburton, Tauranga, Taupo, Rotorua, Turangi, Huntly, Ngaruawahia, Te Kauwhata, Cambridge, Waikeria, Otorohanga, Pukekohe, Rawene, Coromandel, Omaha, Matakana, Queenstown, Invercargill, and Whangarei. The proposed approach is also in line with what has and is happening internationally. In 1991 there were already over 20 constructed wetlands in New Zealand receiving wastewater flow rates ranging from 7.5m3/day to around 4500m3/day. Approximately 43% of treatment plants nationally discharge to land in some way, of which 23% use a high rate discharge to land system, 11% irrigate trees, 11% cut and carry, and 6% grazed pasture. Currently approximately about 11% of the national treated wastewater is discharged onto land. 

Is this a high cost wastewater treatment option, and is it higher than elsewhere in New Zealand?

If you compare Gisborne’s total investment into wastewater treatment (how much we have spent on wastewater compared to other similarly sized wastewater treatment plants), we're well below the national average. Even if Option 5 was chosen, the total investment in wastewater in Gisborne would still not be considered high when compared with other similarly sized wastewater treatment plants. The difference is that Gisborne only started investing in wastewater treatment over the last 20 years, while most other areas have invested in wastewater treatment over a much longer time (and costs have been more spread out in those areas).

How much is Council contributing towards this?

Council pays for all infrastructure through rates revenue, grants, and revenue from some of its assets that make money. Council’s main revenue source is rates, and therefore rates pay for most of the work that Council does.

Will this affect people with their own wastewater systems like septic tanks?

The rating system is designed so that the cost of the wastewater treatment and wastewater pipe network is funded primarily by rates on properties that are either already connected to the wastewater system or could connect to the system if they wanted to. A small part of wastewater funding is from fees and charges, such as disposal from septic tanks.  People with their own wastewater systems may be affected with higher fees when disposing into septage sites. 

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Will the upgrade improve the quality of industrial wastewater?

Not at this stage.  The industrial wastewater is treated on site by the discharger, prior to it entering Council's industrial system. But our consent has requirements for improved water quality from these discharges and will require industrial processes to meet the higher standards in accordance with the consent requirements.

Will everyone have to pay for the cost of the upgrade?

This will be decided through the Long Term Plan process. Through this process, everyone will have the opportunity to comment on how the costs are split. The costs are likely to be borne by all households in Gisborne city that are connected or have the ability to connect into the public wastewater system. This includes tenants in rental accommodation as the costs may be passed on.

How much did the upgrade in 2010 cost?

Approximately $40 million was spent on the first stage of the consent in 2010.

Yes - the consent was a 2 stage consent. Stage 1 was to construct a Biological Trickling Filter (BTF) which then allowed Council to monitor its performance before adding on disinfection. Stage 2 requires disinfection and also allowed sufficient time for Council to investigate not only disinfection but alternative beneficial use of the treated wastewater and if possible removing of all wastewater into the Bay.

The consent still applies and has 2 stages. The infrastructure built in 2010 was only the first stage of the wastewater treatment upgrade as required by the consent. Council is currently deciding on what to do in order to comply with the second stage of the consent. That's why we're consulting with the community, so that the decision can be informed by community feedback.

The first stage of the wastewater treatment plant met the conditions of the first stage of the consent. The proposed wastewater treatment options are designed to address the conditions that form part of the second stage of the existing consent. 

Is the proposal a major upgrade or just fine tuning?

The upgrades required to comply with the water quality standards in the consent require much more than fine tuning. The original consent in 2007 included 2 biological trickling filters, clarification, solids handling, and ultraviolet disinfection at a total project cost of approx $85 million. A consent variation in 2009 permitted Council to split the construction of the $85 million project into 2 stages. To give Council the time to investigate other ways of managing the wastewater, achieve better outcomes that cater for cultural aspects, to look for cost savings, and spread the costs out. Stage 1 was then built in 2010 at a cost of approx $45 million, with stage 2 to be built later. In 2015 Council obtained permission to further delay stage 2. Council is now looking to implement stage 2 as required in the consent.

Are the changes new and do they radically change the treatment process?

The additional treatment components build on what we already have, and all options include components that were integral to the original wastewater treatment plant consent from 2007. The wetland process has been investigated and discussed since the 2009 consent variation, and this component is the final component within the ‘treatment train’ and therefore does not change what currently takes place. 

A key component of the consent is the importance of addressing social and cultural aspects.  These are definitely not met by the current wastewater infrastructure. The consent requires that Council undertakes best endeavours to stop treated domestic wastewater flowing from the marine outfall into the bay, with investigations into alternative use and disposal options to achieve this. In other words, finding ways to use or dispose of the treated wastewater so that it no longer has to be sent out to sea via the marine pipeline.

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Present discharge into the bay

The present discharge complies with stage 1 of the consent. It does not comply with the water quality standards that are specified in the consent, which come into force once the preferred long term wastewater management option is implemented. While a number of important dates are referred to in the consent, the long term wastewater management option essentially requires to be implemented by 2020. If this is not done, then Council will not be compliant with the consent originally set by the Environment Court.

Has the present discharge created any health issues?

The 2015 consent variation concluded that recreational health effects are less than minor, based on the information provided by Council's consultants at that time. This view is not supported by all in the community and iwi, with their concerns summarised below: 
Data has not been collected on health issues attributed to the marine outfall. Ailments contracted on account of wastewater generally are undiagnosed, it's extremely difficult to conclusively link illnesses to any specific source of pollution, and the studies used to support the 2015 consent variation may need to be looked at closer. Further evidence would be required in order to make conclusions on whether there are any infectious or other health issues related to the marine outfall. No modelling has been undertaken to identify when the most risk is present, and what is the general use status at such times. The understanding of health risks has also progressed since 2015, with recognition of risks posed by emerging contaminants. There are therefore different views on this issue.

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The consultation process

What's the purpose of community engagement?

Council has to improve the wastewater treatment plant at Banks Street and has identified 5 options to do this.  All the options are very expensive to build and to run and spending more money gets a higher level of treatment and incrementally better outcomes. Given the cost of these options, we would like to get input from our community who has to pay for the upgrade, to get the most acceptable combination of cost and outcomes.

What's the process for the consultation?

Council is engaging with the community by various means, including social media, a postal survey, our website and talking to people at events and shopping areas. The information  we collect about peoples’ choice of treatment option will be used  to inform which option will be included in our Long Term Plan (LTP) so money is put in the budget along with all the other things Council needs to spend money on over the next 10 years.  Everyone will get a chance to have their say on the LTP when we consult on the draft LTP in March 2018.  This will be another opportunity to provide feedback on the wastewater treatment plant, but Council will already have identified the preferred option at that stage. 

Who came up with the options?

Council has been assisted by 3 community-based advisory groups to help develop or assess viable options for the wastewater treatment plant.  These are the Wastewater Management Committee (WMC), the Wastewater Technical Advisory Group (WTAG) and the Wastewater Options Review Group (WORG).  Council's project team, in collaboration with council subject matter experts and external experts, has worked with the community-based advisory groups to arrive at the 5 options now being consulted on.

Who is on the Wastewater Management Committee?

The Wastewater Management Committee has 8 members, consisting of 4 iwi representatives and 4 councillors. The role is to assist Council in assessing viable options for the wastewater treatment plant. 

What is the role of iwi?

As kaitiaki of the coastal marine environment, iwi have a suite of attendant rights and responsibilities that must be paid particular regard. Also, their relationship with taonga (s6e) must be recognised and provided for.

Finding more information on our website

Links to more information:

Video on the wastewater options

DrainWise - information on the programme that's looking at resolving stormwater issues and related wastewater discharges into the rivers

There is a lot of technical detail on the following web pages:

Wastewater Management Meeting 11 July 2017 - a good overview of the consent is document 17 248 X1 

Wastewater Management Meeting 12 May 2017 

Information related to the wetland component of the wastewater project (which helped decide which options to put forward) Wetlands Trial 2016 

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