Ordinary meeting of the


Nelson Regional Sewerage Business Unit



Friday 10 March 2017
Commencing at 1.00pm
Ruma Mārama

Civic House

110 Trafalgar Street, Nelson


Membership: Nelson City Councillors Tim Skinner, and Stuart Walker, Michael Higgins (Chairperson) and Tasman District Councillor Kit Maling (Deputy Chairperson)


Representatives: M Hippolite (Iwi Representative) and P Wilson (Industry Customers Representative)

Guidelines for councillors attending the meeting, who are not members of the Committee, as set out in Standing Orders:

·      All councillors, whether or not they are members of the Committee, may attend Committee meetings (SO 2.12.2)

·      At the discretion of the Chair, councillors who are not Committee members may speak, or ask questions about a matter.

·      Only Committee members may vote on any matter before the Committee (SO 3.14.1)

It is good practice for both Committee members and non-Committee members to declare any interests in items on the agenda.  They should withdraw from the room for discussion and voting on any of these items.


Nelson Regional Sewerage Business Unit

10 March 2017



Page No.



1.       Confirmation of Order of Business

2.       Interests

2.1       Updates to the Interests Register

2.2       Identify any conflicts of interest in the agenda

3.       Public Forum

4.       Confirmation of Minutes

4.1       9 December 2016                                                       5 - 9

Document number M2258


That the Committee

Confirms the minutes of the meeting of the Nelson Regional Sewerage Business Unit, held on 9 December 2016, as a true and correct record.    

5.       General Manager's Report                      10 - 108

Document number R7164


That the Committee

Receives the report General Manager's Report (R7164) and its attachments (A1663508, A1711018, A1711017, A1692595, A1713024); and

Approves expenditure up to $29,000 in the 2017/18 year for the initial eradication treatment of Argentine Ants at Bell Island, scheduled for November 2017.

6.       Financial Report                                    109 - 111

Document number R7263


That the Committee

Receives the report Financial Report to 31 January 2017 (R7263) and its attachment (A1721459).






Minutes of a meeting of the Nelson Regional Sewerage Business Unit

Held in Ruma Mārama, Floor 2A, Civic House, 110 Trafalgar Street, Nelson

On Friday 9 December 2016, commencing at 1.00pm


Present:               Councillors T Skinner and S Walker (Nelson City Council), K Maling (Tasman District Council), and M Higgins (Tasman District Council Representative)

In Attendance:     Nelson Regional Sewerage Business Unit Manager (R Kirby), Senior Asset Engineer – Solid Waste (J Thiart), Industry Customers’ Representative (P Wilson), Iwi Representative (M Hippolite), Management Accountant (A Bishop), and Administration Adviser (L Canton)




1.       Appointment of Chairperson

Nelson Regional Sewerage Business Unit Manager (NRSBU), Richard Kirby explained that the order of the agenda had changed and the first item of business would be the election of a Chairperson. 

Mr Kirby called for nominations from the voting members for the appointment of a Chairperson. 

Resolved NRSBU/2016/013

That the Business Unit

Appoints Michael Higgins as Chairperson of the Nelson Regional Sewerage Business Unit.     

Maling/Walker                                                                      Carried

2.       Appointment of Deputy Chairperson

Michael Higgins assumed the Chair and called for nominations from the voting members for the appointment of a Deputy Chairperson.

Resolved NRSBU/2016/014

That the Business Unit

Appoints Councillor Kit Maling as Deputy Chairperson of the Nelson Regional Sewerage Business Unit.

Walker/Higgins                                                                     Carried

3.       Confirmation of Order of Business

The Chairperson advised that since the agenda had been issued, a public forum presentation had been confirmed.

4.       Interests

Philip Wilson advised that he was a member of the Waimea Estuary Committee.

Matthew Hippolite advised that he was employed by the Department of Conservation and would potentially be involved with the Bell Island Spit Restoration Project. 

5.       Public Forum

5.1       Gillian Bishop - Bell Island Spit Restoration Project

Gillian Bishop gave a presentation (A1679997) on the restoration of the Bell Island Spit over the last six years.  She noted that it was a model of a community agency/council partnership with significant environmental benefits.  Ms Bishop said that the area should be self-sustaining within about four years. 

Ms Bishop answered questions about the source and varieties of plants on the Spit.


1    A1679997 - Public Forum - Gillian Bishop - Bell Island Spit Restoration presentation

6.       Annual Report 2015/16

Management Accountant, Andrew Bishop, advised that Audit New Zealand had indicated that an approval letter would be forthcoming.  He said he was confident that this would be received by the end of 2016 as required by the Nelson Regional Sewerage Business Unit (NRSBU) Memorandum of Understanding. 

7.       Bell Island Wastewater Treatment Plant - Pond Sludge Management

Document number R5951, agenda pages 7 - 18 refer.

NRSBU Manager, Richard Kirby, presented the report.  He explained that even if the proposed system did not reduce the build-up of sludge, it would result in sufficiently improved mixing and effluent processing to justify the proposed investment. 

Mr Kirby and Senior Asset Engineer – Solid Waste, Johan Thiart, answered questions relating to the estimated wind resource, the potential for bird or lightning strikes, and the expected lifetime of the system. 

Resolved NRSBU/2016/015

That the Business Unit

Receives the report Bell Island Wastewater Treatment Plant - Pond Sludge Management (R5951); and

Approves proceeding with engaging Gurney Environmental for the supply and delivery to Nelson of 9 (nine) Accel-o-Fac series three aerator/mixers in Pond F2 up to 50% of the value of $280,000 (excl GST); and

Approves the investment of up to $60,000 to install the 9 (nine) Accel-o-Fac series three aerator/mixers in Pond F2; and

Approves the negotiation of a variation to the Operation and Maintenance contract for the installation of nine Accel-o-Fac aerator/mixers in facultative pond F2 and;

Approves funding for the upgrade of the maturations ponds and desludging of the ponds in the 2015/16 and 2016/17 Business Plans be utilised for this initiative; and

Approves the monitoring of effluent quality in chambers C4, C5 and C6 to assess the performance of upgraded pond (F2) compared to the other two facultative ponds (F1 and F3); and

Requests that the outcome of the monitoring be reported back to the NRSBU for approval prior to the remaining 50% payment being made to Gurney Environmental.

Skinner/Walker                                                                     Carried


8.       Bell Island Wastewater Treatment Plant - Electrical Power Business Continuity Assessment

Document number R6834, agenda pages 20 - 29 refer.

NRSBU Manager, Richard Kirby, presented the report. 

Mr Kirby and Mr Thiart answered questions relating to the effect on the inlet screens in the event of a power supply disruption, discussions with Network Tasman, and alternative power sources.

Resolved NRSBU/2016/016

That the Business Unit

Receives the report Bell Island Wastewater Treatment Plant - Electrical Power Business Continuity Assessment (R6834); and

Notes the offer from Network Tasman to fund 50% of the capital cost ($447,000) of installing a second cable to the Bell Island Wastewater Treatment Plant has been declined; and

Approves adding the option of including the installation of permanent backup generation for the Inlet Structure and Discharge Pump (250 kVa) in the draft Business Plan 2017/18.

Maling/Skinner                                                                      Carried

9.       General Manager's Report

Document number R6816, agenda pages 30 - 137 refer.

NRSBU Manager, Richard Kirby presented the report.  He explained that no definitive evidence of efficacy had been provided by Bokashi Logic. 

Mr Kirby and Mr Thiart answered questions relating to the classification of accidental discharges by each Council, and the extent of infrastructural changes required to prevent accidental discharges altogether.

Attendance:  Councillor Skinner left the meeting from 2.54pm to 2.56pm.

Mr Kirby answered further questions about the timeframe and potential costs of the discharge consent renewal. 

Resolved NRSBU/2016/017

That the Business Unit

Receives the General Manager's Report (R6816) and its attachments (A1649724, A1665105, A1645078, A1436459, A452094, and A1664757); and

Declines the proposal from Bokashi Logic to implement treatment at Bell Island Treatment Plant.

Skinner/Maling                                                                      Carried

9.1       Draft business Plan 2017/18

The Board discussed expected growth and the infrastructure needed to meet potential increased demand. 

Resolved NRSBU/2016/018

That the Business Unit

Approves the Draft Business Plan 2017/18 (A1664757).

Higgins/Walker                                                                     Carried

10.     Financial Report

Document number R6885, agenda pages 138 - 140 refer.

Andrew Bishop presented the report. He tabled an updated final page (A1680118) and explained the changes. 

Resolved NRSBU/2016/019

That the Business Unit

Receives the Financial Report (R6885) and its attachment (A1629394).

Skinner/Maling                                                                      Carried


1    A1680118 - NRSBU Financial Report - tabled document - 09Dec2016


There being no further business the meeting ended at 3.40pm.

Confirmed as a correct record of proceedings:




                                                         Chairperson                                    Date



Nelson Regional Sewerage Business Unit

10 March 2017




General Manager's Report



1.       Purpose of Report

1.1       To report on the NRSBU operational activities over the last few months and outline what is proposed over the next few months.


2.       Recommendation

That the Committee

Receives the report General Manager's Report (R7164) and its attachments (A1663508, A1711018, A1711017, A1692595, A1713024); and

Approves expenditure up to $29,000 in the 2017/18 year for the initial eradication treatment of Argentine Ants at Bell Island, scheduled for November 2017.




3.       Accidental Discharge Consent

3.1       The NRSBU lodged an application for a resource consent for the accidental discharge of wastewater into the estuary.  This was primarily from the NRSBU reticulation and pump stations.

3.2       This was initially lodged on 23 July 2015 with the Nelson City Council (consenting authority). NCC subsequently requested additional information and this was collated and lodged 29 February 2016. 

3.3       The application was notified publicly during August/September 2016 and submissions closed at the beginning of November 2016.

3.4       Thirty five submissions were received.

·    One submission was in support of the consent.

·    Four of the submissions did not oppose the consent application and asked to be heard.

·      The other submissions all opposed the application submission mainly on the grounds that the discharge of any raw sewage to the Waimea Inlet is unacceptable.

3.5       The team of consultants are preparing evidence for the consent hearing that will take place in May 2017. (The date is to be confirmed)

4.       NRSBU Resource Consent Renewal Bell Island Wastewater Treatment Plant

4.1       Following procurement processes MWH was appointed as the primary consultant for the renewal of the discharges resource consents for Bell Island and Duncan Cotterill as the legal advisers for the consent application.

4.2       The project team have met on two occasions over the last month to finalise the scope of work and the programme. There are some additional tasks that need to be undertaken. These comprise a consent for discharge to land (seepage), discharge to land (centre pivot), occupation and use of Coastal Marine Area (CMA) and consent for the maintenance of the outfall pipeline/diffuser.

4.3       There is also a need to undertake a desktop study on the trace organic compounds (TOrC) that have recently been raised as a potential issue in wastewater discharges. This has only recently become apparent and we are endeavouring to assess the scale of the issue.

4.4       The NRSBU is in the process of scoping the iwi consultation for this application. It has engaged a resource to help facilitate this aspect. 

4.5       The project is on programme to lodge the consent in August 2017.

5.       Endocrine Disrupting Compounds (EDCs)

5.1       The ‘normal’ composition of wastewater is continually changing. Clause 3.3 outlined the recent need to assess TOrC’s within the wastewater discharges. There are many other emerging contaminants which are able to form complex mixtures of EDCs that can be detrimental to the environment and to human health. These originate in many steroids and other drugs that are becoming more prevalent within the community.

5.2       Independent research has shown that the treatment process at Bell Island significantly reduces these compounds prior to the wastewater discharge.

5.3       The capacity of the Bell Island treatment plant is considered to be similar to the best performing treatment plants. The report (appended) states that “All wastewater treatment plants exhibited similar concentrations of the estrogenic steroid hormones entering and exiting the plants.”

5.4       Northcott Research Consultants have been requested to develop a proposal to track the quality of wastewater through the ponds in terms of micro-pollutants. This work will benefit the work towards the discharge consent renewal and provide guidance in terms of the capacity of the ponds to remove these compounds from the treated wastewater discharge.

6.       Argentine Ants

6.1       The Tasman District Council issued a notification under the Tasman-Nelson Regional Pest Management Strategy Rule 6.1.5 that Argentine Ant infestation has been observed at Bell Island.

6.2       The ant infestation appears to be limited to a 12.5 Ha area as shown on the plan in the attachment.

6.3       It is considered that early action will limit the spread of these ants and that an eradication programme is achievable.

6.4       In accordance with the notice the NRSBU must initiate a programme to manage the ants by November 2017.

6.5       Nelmac quoted $9,450 to bait the area directly around infrastructure and boundary strips from the plant to the beach to isolate the area this work will then be followed up with an initial eradication treatment in November 2017.

Figure 5.5 Managing Argentine ant infestation

6.6       The cost for an initial eradication treatment is up to $29,000 and it is proposed to be carried out during November 2017.

6.7       It was therefore decided to commence with the initial eradication treatment to get best economic and environmental protection value.

6.8       Once the success of the initial eradication programme has been evaluated a further report will be submitted to the Board.

7.       Coastal Effects of the Bell Island Treated Wastewater Discharge: Benthic Monitoring Survey 2016

7.1       This is a report that the NRSBU commissions every 5 years to determine the ecological impact of the treated wastewater discharge.

7.2       The monitoring of sites showed no evidence of abnormal sediment anoxia or organic enrichment.

7.3       There is no evidence of cumulative enrichment due to Bell Island wastewater discharges.

7.4       As in previous surveys, biological communities at all site were healthy and functioning.

7.5       The report suggests that future surveys include analysis of nitrogen and phosphorous at a slightly deeper depth considering the findings of experimental studies that suggest that additional nitrogen inputs to estuarine sediments may result in elevated ammonium concentrations in deeper sediments (5-7cm) rather than the surface layer (0-2cm).

8.       Treated Wastewater Recirculation

8.1       A trial was initiated late December 2017 to demonstrate that the recirculation of treated wastewater from the discharge channel back through the ponds will create improved discharge quality by decreasing the retention time of treated wastewater in the individual maturation ponds. (Note that the three facultative ponds operate in parallel, discharges to the first maturation pond and then on to the final maturation pond)

8.2       Treated wastewater is pumped by means of the algae seeding pump from the discharge channel back into Facultative pond F1. (At a rate of approximately 8% of the capacity of the final maturation pond per day)

8.3       At the time when the trial started the algae in F1 was lagging well behind the other two ponds in both diversity and total algal numbers. To date the diversity of algae in F1 is significantly better than that in the other two ponds. Over the period of the trial to date F1 has outperformed the other two ponds significantly in both attributes but specifically in terms of algae diversity.

8.4       More significantly no adverse conditions have been observed in F1. This provides confidence that an increase in circulation will likely improve the condition in all the ponds if the treated wastewater is circulated through all three facultative ponds.

8.5       A recirculation pump can be sized to decrease the retention time of treated wastewater in the final maturation pond by half and is expected to decrease the density of algae in this pond (and therefore suspended solids in the discharge) allowing for increase sunlight penetration resulting in improved discharge quality.

8.6       The trial is expected to continue for four months.

9.       Upgrade and renewal of mixers in Facultative Pond F2

9.1       In December 2016, the NRSBU approved proceeding with engaging Gurney Environmental for the supply, delivery and installation of 9 (nine) Accel-o-Fac series three aerator/mixers in Pond F2, Bell Island Wastewater Treatment Plant.

9.2       These Accel-o-Fac mixers have been manufactured and shipped from England and are expected to be installed in April 2017.

9.3       It is anticipated that results of the testing for micro-organism, as discussed in section 4, will provide data that could be used, with other monitoring, to demonstrate the efficacy of the improvements derived from improved mixing in this pond relatively to a neighbouring pond.

10.     Contract 3458 – Operation and Maintenance

10.1     The reticulation and treatment operations have continued as normal over the last few months.  The effluent discharge continues to meet consent conditions and sludge produced at the treatment plant complies with Class A biosolids quality.

10.2     The ponds continue to perform well.  Loads are diverted away from the activated sludge area and into the ponds to utilise the capacity of the ponds during the summer months resulting in energy savings in the aeration basin.

10.3     Maintenance and renewal of the scraper mechanism and steel components in the secondary clarifier were completed during January 2017.

Figure 9.3.1 Rust on scraper mechanism.

Figure 9.3.2 Rusting of lauder brackets

10.4     The condition assessment of the secondary clarifier has shown that all the joint seal cover strips needed replacement and minor concrete corrosion that required the application of a seal to protect the concrete from further corrosion.

Figure 9.4 Shows cover strip used to protect joint seal

10.5     The activated sludge area should be ready to be commissioned in early March. The ponds are managing the loads.

11.     Contract 3619 – Biosolids Operation

11.1     The monthly volume of biosolids sprayed at Rabbit Island has dropped significantly over the last two months and is expected to stay at current levels until at least April.

11.2     The projected volume of biosolids that will be sprayed this year will likely exceed the budget projection by a moderate margin.


12.     Key Performance Indicators

12.1     The outcomes of key performance indicators for the 3 month period to 31 January 2017.


13.     Compliance Outcomes

13.1     The compliance outcomes for the 12 months to 31 January 2017 are outlined in the following table:


Resource Consent Compliance (rolling 12 month record)


Ø Discharge to Estuary Permit



Ø Accidental discharges (Consent for accidental discharges within Nelson City Council area is being sought at present)

Overflows occurred at the Beach Road, Saxton Road and Songer Street pump station during the heavy rain event on 24 March 2016. The rainfall event is the second highest rainfall recorded over a 24 hour period recorded for Nelson since January 2000.

An overflow occurred at the Songer Street during wet weather conditions when both storm pumps blocked on 22 June 2016.

Biosolids overflow to land and the Waimea estuary following a blow out on biosolids transfer pipeline on 19 and 20 July 2016.


Ø Discharge to Air Permit

100% Compliance


Ø Biosolids Disposal

100% Compliance


Ø Discharge treated 

waste water to land

100% Compliance


Odour Notifications


Ø Past three months



Ø Last 12 months





Ø Past three months



Ø Last 12 months



Speed of response for maintenance works


In past three months:

Ø Five call outs were associated with treatment plant issues.

·      Aeration basin aerator – 1 event.

·      Primary clarifier sludge pumps – 2 events.

·      Milliscreen – 1 events.

·      Power outage during storm event – 6 hour duration.

Ø No call outs recorded for pump stations.


Ø Response within 30 minutes.  Achieved.



14.     Review of Action Plan Implementation –
2014 Asset Management Plan and 2016/17 Business Plan

The following table indicates the draft time lines for the individual action items:


Business Plan Action

Target Date

Completion Date



Review manuals annually.

Apr 2017


Delayed. Contract manuals are reviewed annually by the contractor and submitted to the NRSBU for review. All the manuals have been reviewed with the exception of the Operation and Maintenance Manual. It is expected that this will be comleted in April 2016.


Consolidate all natural disaster information and review 3 yearly.

May 2017


Work will be carried out as part of next asset management review.



Internal benchmarking carried out annually.

Jun 2016

Aug 2016

Carried out as part of annual report.


Review risk of contributors leaving NRSBU.

Jun 2016

Dec 2015



Review capacity of treatment components.

May 2017


Expect treatment plant model to be in place in March 2017. This will follow an assessment of S::can results.


Programme for pipe inspections.

Apr 2017


Included in annual review of Operation and Maintenance Plan.


Annual review of contractor performance.

Dec 2016

Jun 2016



Screen upgrade.

April 2017


Variation issued to Nelmac to project manage the installation of the second inlet screen.


Review secondary sludge separation.

May 2017


Depends on completion of treatment plant model.


Construction second sludge storage tank.

Jun 2018


Delayed from June 2016.


Develop sludge removal programme.

May 2018


Subject to review of the performance of the improvement of mixing in F2.


Review effluent discharge management.

Mar 2016

Jan 2016



Renewal of effluent discharge permit

Aug 2018


On schedule.


AMP Action

Target Date

Completion Date



Annual customer survey.

Mar 2016

Apr 2016



Business Continuity Plan review.

Jun 2016

Jun 2016



Consider benefits of succession planning and how it might be implemented once governance issues (TDC and NCC) have been resolved.

Jun 2016

June 2016



Review of security required at all facilities.

Mar 2016

May 2016



Monitor sludge levels in ponds and ascertain long term removal and disposal requirements.

Mar 2016

Feb 2006



Improve reporting requirements for asset condition, performance and maintenance from maintenance contractor.

Mar 2016

Apr 2016



Implementation of internal bench marking (using historical data) of NRSBU network, pump stations, treatment and disposal facilities.

Jun 2017

June 2017

Still to be intiated


Develop Demand Management Policy.

Jun 2016

Jun 2016


15.     Health and Safety

15.1     There have been 14 inductions and 192 visitors to the Bell Island WWTP over the past three months.

15.2     Four Health and Safety incidents were reported.

15.2.1  Operator pricked by a hypodermic needle when attending to the milliscreen. All vaccinations are up to date.

15.2.2  Operator strained a muscle in his back when attending to the milliscreen.

15.2.3  Near miss: Incorrect pump isolated at pump station. All pumps have now been labelled to correspond with VSD’s.

15.2.4  Wing mirror of a Ute was knocked off when a protruding pump part carried on a different Ute hit the mirror.

16.     Financial Status

16.1     Expenditure is tracking above budget. This is partly a result of dealing with the biosolids transfer pipeline blockages and the blow out which was not budgeted for.

16.2     There has also been an increase in monitoring costs:

·    The testing daily trade waste samples collected from the three industrial contributors, as arranged following the review of the Agreement for Disposal of Trade Waste.  This additional testing cost $3,000 per month.

·    The cost of the five yearly environmental monitoring associated with the treated wastewater discharge. This cost was budgeted for in year 2017/18 instead of 2016/17.

16.3     The cost of biosolids spraying is expected to exceed the budget by $30,000 for this financial year.  The decrease in biosolids volume following the introduction of sludge thickening has not eventuated as anticipated, however there should be a decrease in sludge volumes through to the end of the year.

16.4     The cost of power supply is tracking well below budget and the annual cost is expected to be well under budget.

16.5     Overall the current projections show that operation and maintenance expenditure could exceed the budget by over $50,000 to $70,000. To compensate for this increased expenditure, discretionary expenditure will be deferred where feasible.



Richard Kirby

Consulting Engineer


Attachment 1:    NRSBU Bell Island Endochrine Disrupters A1663508

Attachment 2:    Bell Island Argentine Ants A1711018

Attachment 3:    Argentine Ants Biosecurity Notice A1711017

Attachment 4:    Coastal Effects: Benthic Monitoring 5 yearly report A1692595

Attachment 5:    Status report 10 March 2017 A1713024



Important considerations for decision making

1.   Fit with Purpose of Local Government

This update fits in with the purpose of local government as it contributes to meeting the current and future needs of the community for good quality local infrastructure and local public services.

2.   Consistency with Community Outcomes and Council Policy

The report is in line with the objectives of the NRSBU in the provision of cost-effective collections and treatment of wastewater.

3.   Risk

There is no risk in the recommendation to receive this report.

4.   Financial impact

The additional cost associated with eradication of Argentine Ants will nominally increase operational expenditure.

5.   Degree of significance and level of engagement

The recommendation to receive this report is of low significance.

6.   Inclusion of Māori in the decision making process

Maori have not been consulted on this matter.

7.   Delegations

This is a matter for the NRSBU.



























































































Nelson Regional Sewerage Business Unit

10 March 2017




Financial Report



1.       Purpose of Report

1.1       To consider the Financial Report to 31 January 2017.



2.       Recommendation

That the Committee

Receives the report Financial Report to 31 January 2017 (R7263) and its attachment (A1721459).








Andrew Bishop

Management Accountant


Attachment 1:    A1721459 - NRSBU Financial Report to 31 January 2017