1. Lake Tarawera Sewerage Steering Committee
Community update 14th January 2018
Glenn Snelgrove
Independent Chair
Lake Tarawera Sewerage Steering Committee

2. Lake Tarawera Sewerage Steering Committee cont.
Lake Tarawera Ratepayers’ Association
Libby Fletcher
Terry Beckett
Lake Tarawera Community
Anaru Rangiheuea (also Tuhourangi)
Richard Noke
Lakes Water Quality Society
Neil Callaghan
Tarawera Lakes Restoration Committee
John Ford
Barnett Vercoe - Onuku Maori Land Trust
Chris Sutton
Rotorua Lakes Community Board
Jim Stanton
Tarawera Lakes Protection Society
Fred Stevens
Tuhourangi Tribal Authority
Alan Skipwith
Te Mana O Ngāti Rangitihi Trust
Ken Raureti
Chris Clarke
Te Arawa Lakes Trust
Karen Vercoe
Nicki Douglas
Rotorua/Taupo Federated Farmers
Gifford McFadden
Rotorua Lakes Council
Cr Tania Tapsell
Cr Mark Gould
Monty Morrison
Bay of Plenty Regional Council
Kevin Winters
Ministry of Health
Annaka Davis
Technical Advisory Group
Taupiri McLeod
Ngāti Te Rangiunuora
Peri Marks
Wally Lee

3. Lake Tarawera Sewerage
Purpose of Tarawera Sewerage Steering Committee
The Tarawera Sewerage Steering Committee (TSSC) is established to reach consensus on a preferred sewage disposal option for Tarawera
To recommend a solution to the Rotorua Lakes Council
To work with appropriate funding agencies to obtain an approved level of funding and subsidy to enable the construction of a suitable sewage disposal scheme at a cost acceptable to the community.

4. Lake Tarawera Sewerage
Goals
The Committee is to select amongst options for the scheme, which is overall the best practicable option, and which:
Contributes best to improving the water quality in Lake Tarawera by reducing such nutrient and contaminant flows from homes and properties as enter into the lakes.
Recommends “the best practical option” in terms of the Resource Management Act (RMA)

5. Lake Tarawera Sewerage
Goals Continued
Best meets the needs of the community and the cultural needs of tangata whenua.
Achieves environmental outcomes.
Best safeguards public health.
Complies with regulatory requirements, national and regional.
Attracts appropriate subsidy funding.
Is the most cost effective option for local rate payers as well as Rotorua Lakes Council.
Has community support.

6. Lake Tarawera Sewerage
Responsibility and reporting of TSSC
The TSSC is a meeting of equals among stakeholders: community groups (especially iwi), authorities (especially Rotorua Lakes Council), and such other stakeholders as may have an interest.
The TSSC is not a Statutory Committee and is not subject to direction by Rotorua Lakes Council, nor is there any delegation of Council decision making authority to the TSSC.

7. Lake Tarawera Sewerage
Responsibility and reporting of TSSC
The TSSC is to report to the community and to Rotorua Lakes Council.
The TSSC is to recommend to Rotorua Lakes Council its preferred option for a sewerage scheme and make such representation to both the RLC and BoPRC annual and long term plans and policies in support of its recommendations. This does not preclude any member of the committee making a submission in their own right.

8. Lake Tarawera Sewerage
TSSC engagement and reporting functions
The TSSC may occasionally seek broader stakeholder input by convening workshops, stakeholder forums or by other appropriate means. This engagement shall be done in conjunction with Rotorua Lakes Council.
The TSSC shall report regularly to Rotorua Lakes Council. The frequency and form of this reporting shall relate to the timeline of the proposed scheme.
The TSSC after agreement by Rotorua Lakes Council, shall report to the public at appropriate times.

9. Lake Tarawera Sewerage
Lake Tarawera Restoration Plan
Developed with the community.
Plan approved by both Councils. Te Arawa Lakes Trust and community. Community Plan Committee is Chaired by Libby Fletcher
Has a number of actions to improve the environment.
Number one priority is to reticulate wastewater.

10. Lake Tarawera Sewerage
Cultural Impact Assessment
Acknowledgment TLT Abridged version of presentation

17. Key Recommendations CIA
From the report the committee received the four guiding principles of;
1 The best option that halts the decline in Lake water quality. Te Mauri o te Wai
2 Enables the return of Iwi and best use of Maori land
3 The option that has least impact on the sites of significance
4 The management of waste and the respect for one another Tekanga

18. Lake Tarawera Sewerage
Cultural Impact assessment stage two
Currently being scoped
Stage two will focus on the committees preferred options
Engage the four principles
Consult with Iwi and Hapu
Consult with Maori Land Trusts
Recommend findings and preferred option
Identify mitigation if needed

19. On-site Wastewater Capability Project
Undertaken by Bay of Plenty Regional Council
Acknowledgements
Trisha Simonson – Louise Feathers Planning Ltd.

20. Current Situation Water quality in Lake Tarawera is declining.
BoPRC classified Tarawera as a Maintenance Zone and Future Reticulation Zone.
From 1 December 2017 all septic tanks will be a discretionary activity, requiring resource consent.
All aerated wastewater treatment plants (AWTS) must meet a nitrogen standard or require resource consent.
Reticulation options are being investigated.
Should reticulation not be the preferred option, then continued use of on-site systems is required.
Can sustainable, lawful on-site wastewater management occur for the Lake Tarawera community?

21. OSET Capability Project
A range of environmental constraints were identified by BoPRC which limit effective and sustainable OSET management at Tarawera.
The project sought to confirm whether or not these constraints exist, and to what extent.
Used GIS and BoPRC data to identify areas to visit.
Field investigation including soil testing and site inspections.
Colour grading of properties, green to red.
Identified what is required for properties to be compliant with BoPRC rules.
Overall conclusions made.
Full report available at Steering Committee meeting.

23. Identified Constraints
A range of environmental constraints have been identified by BoPRC which limit effective and sustainable on-site wastewater management at Tarawera:
Existing Systems
Soil Type
Property Size
Proximity to Groundwater
Land Slope

24. Data Gathering GIS Data from BoPRC used as follows:
Maps generated showing areas greater than 15 degrees in slope.
Used with aerial photos to identify sites with less than 250m2 disposal area.
Soil maps used to identify areas with Rotomahana soil types.
Property size from Prover.
Groundwater level from BoPRC topography.
Data used to select five areas to undertake site inspections and the locations for soil investigations.

26. Desk-Top Results Existing Systems
391 OSET systems, 11 Resource Consents.
9 AWTS systems, 382 Septic Tanks (97%).
177 Soak Hole systems (45%), 75 Trench systems (19%).
Where septic tank size known, 276 were less than the recommended minimum size of 3,000 litres (80%).
Soil Type – Rotomahana Mud description from literature
Property Size – urban scale, 70% less than 1500m2.

27. Field Investigation Results
Soil Investigation
11 boreholes drilled.
Rotomahana Mud identified in 9 holes.
Groundwater intercepted in two holes at 800mm and 1000mm depth
Percolation tests in four boreholes.
Average permeability measured at 0.1m/day, worst case 0.05m/day.
Given permeability, soil texture and lack of topsoil, the soil is classified as category 6 (AS/NZS 1547:2010).
On the basis of the soil tests, the area required for wastewater disposal per lot was revised to 600m2, based on a loading rate of 2 mm/day and a 4-bedroom dwelling.

28. Field Investigation Results
Site inspections:
107 properties or 27% were inspected.
Confirmed that 40%+ sites inspected had steep slopes and limited level areas generally occupied by buildings.
17% of properties had an issue with existing systems e.g. odour, breakout, too close to watercourse, broken tank lids, systems under driveways or decks.
64% of dwellings sourced water from Lake Tarawera.
Some sites had multiple dwellings and outbuildings limiting available area.
On 27% of sites, it was difficult to establish the location or type of disposal system.
Where owners were present, most indicated their systems had been serviced within 12 months.

29. Collapsing Tank
Broken Tank Lid
Tank under Driveway
Typical Site Area

30. OSET Colour Grading
The constraints identified by BoPRC and confirmed by the field investigation were assessed for all properties.
Where sites were not visited desk-top data used to determine colour grading.
Results:
Green: Permitted Nitrogen Removing Systems (2 properties) = Acceptable
Yellow: AWTS and Consent Septic Tanks Systems (16 properties) = Short Term Acceptable.
Orange: Upgrade Work Required (204 properties) = Need Significant Upgrades
Red: Unable to Meet the Standard Required (169 Properties) = No Solution Available

31. Colour Grading Pie Chart

32. OSET Plan Compliance
If a reticulation scheme is not pursued, the Tarawera OSET systems must be compliant under the OSET Plan by either:
Installing a Nitrogen Reducing AWTS System, or
Gaining Resource Consent for a septic tank system (that meets modern standards) as a discretionary activity.
For the 220 Orange or Yellow Properties, this means around $16,000 for a new AWTS, or a consent (which may be declined as septic tanks do not meet the required N reduction).
For the 169 Red Properties current, solutions have not been determined. Further investigation may find specific solutions. Some properties are very severely limited and pump-out of wastewater may be the only option.

33. Summary and Conclusions
Effective and sustainable on-site wastewater management at Lake Tarawera is severely constrained.
On-site disposal is contributing to the nutrient and pathogen loads discharging into Lake Tarawera.
The majority of Tarawera properties (95%) do not meet current standards.
On-site systems are not likely a valid option for 43% of the community and a further 56% face significant upgrades.
Given the evidence of the impacts of OSET discharges and the upgrades required, it is considered important that the settlement is reticulated.

34. OSET Plan Compliance The OSET Plan requirements for Lake Tarawera are:
Existing septic tanks are permitted subject to having an outlet filter and having sludge removed.
Existing AWTS within 200 metres of the lake edge are permitted.
A new AWTS+NR system is a permitted activity.
Other new systems require a resource consent.

35. OSET Plan Compliance The OSET Plan requirements for Lake Tarawera are:
Houses which are expanded, altered or reconstructed can install an AWTS+NR as a permitted activity. For those who do not wish to install an AWTS+NR, a resource consent is required for some other type of system.

36. OSET Plan Compliance The OSET Plan requirements for Lake Tarawera are:
There are a number of existing property owners who are not complying with Maintenance Zone requirements, or have not complied with resource consent requirements. There are also failing on-site effluent treatment systems. The wastewater systems on these properties are contributing to adverse effects on Lake Tarawera.
Council does not wish to authorise inadequate new systems which will make the existing situation worse.

37. OSET Plan Compliance The OSET Plan requirements for Lake Tarawera are:
BOPRC Recommendation is that property owners engage an approved wastewater system designer to develop a proposal which will comply with the current requirements of the operative OSET Plan. Resource consents may be granted for systems that;
comply with the relevant New Zealand Standard(s),
appropriate to site restrictions, and
do not exacerbate the problems associated with nutrients discharged into the Lake.

38. Sewerage Options for Tarawera
Acknowledgement
Greg Manzano
_______________________________________________________________________

39. PROPOSED SERVICE AREA Number of properties: Current - 423
Ultimate - 546

40. INDICATIVE CAPITAL COST (MAY 2017)
POTENTIAL SERVICING OPTIONS
INDICATIVE CAPITAL COST (MAY 2017)
Option
Description
Collection, Reticulation and Transfer
($M)
Treatment and Disposal
Total Capital
Cost Estimate 1A
LPGP system connected to Okareka scheme via Tarawera Road
$14.7
$2.7
$17.4 1B
LPGP system connected to Okareka scheme via Playnes farm
$12.5
$15.2 1C
OPGP system connected to a local WWTP and LDS
$6.4
$18.9 2A
STEP system connected to Okareka scheme via Tarawera Road
$16.9
$19.6 2B
STEP system connected to Okareka scheme via Playnes farm 2C
STEP system connected to local WWTP and LDS
$21.1
NOTE: STEP system options about $2M more expensive than LPGP systems

41. LOW PRESSURE GRINDER PUMP SYSTEM
Houses at Tarawera connected by low pressure grinder pumps
About 1500 installed within the district over the last 9 years

42. STEP SYSTEM
Underground septic tank (about litres) provides primary treatment (solids settling) so only liquids go to treatment plant.
The solids remain in tank for years
and decompose through anaerobic
process. Remaining solids pumped
every seven years (approximately.)
Solids filtered out.
25mm line connects property to main sewer in street.

43. PROPOSED WASTEWATER TREATMENT PLANT AND LAND DISPOSAL SYSTEM CONCEPT
Wastewater Treatment – Membrane BioReactor Plant
(600m³/day approx.)
Land Disposal System – Trench based Rapid Infiltration.
Approximate area requirement
- 5-6 hectares (depending on soil characteristics and buffer requirements.)
Solids management – Stored on site and transported offsite.
Odour management – Enclose all odour generating processes
with foul air extraction and treatment.
Noise management – Blowers house inside blower room with acoustic silencers.
Indicative cost - $6.0M to $6.50M.

44. PROPOSED WASTEWATER TREATMENT PLANT AND LAND DISPOSAL SYSTEM
EMERGENCY STORAGE TANK
SOLIDS MANAGEMENT BUILDING
PROCESS TANKS
PERMEATE TANK
CONTROL/BLOWER BUILDING
Indicative perspective view of Tarawera Wastewater Treatment Plant

45. ASSESSMENT CRITERIA APPLIED
Proximity to receptors
- Neighbouring dwellings / urban areas
- Cultural/historically significant sites
- Groundwater users
- Rivers and streams
- High use stream management areas
- Ecologically significant sites
Distance from proposed reticulation
Nearer site means lower capital and operations cost
Site topography
Flatter slopes are ideal
Designations
ONFL – Outstanding natural features and landscape
Geology
Higher permeability is better suited for RI disposal

46. Committees Recommendations
That the best practical option for local collection of wastewater is LPGP Grinder Pumps with STEP as a back up option.
Reasons
Topography of the land very sloping.
Capacity of the system LPGP can take higher loadings.
Cost effective - is the cheapest cost.
Geology Rotomahana Mud.
Note Subject to CIA report.

47. Committees Recommendations
The best practical option
That the effluent be pumped to one of two connections at Lake Okareka - Playnes farm connection or Connect to Lake Tikitapu (Blue Lake).
Reasons
Lake Okareka made allowance for Tarawera.
Get all nutrients out of the catchment .
No Resource Consents required.
Easiest to construct.
Cheapest of disposal options.
Note Subject to CIA report.

48. Committees Recommendations
That a detailed CIA (Cultural Impact Assessment) be undertaken by TLT (Te Arawa Lakes Trust) providing advise on (in no particular order)
The aspiration of Maori and Maori land owners.
The removal of nutrients and contaminates from the lake catchment. Enhancing the Mana of the Lake and its significance.
Any Cultural issues with the alignment of both reticulation and trunk mains. Playnes Farm or Lake Tikitapu and The onsite treatment of effluent if required.

49. Committees Recommendations
That funding applications be made to both the Bay of Plenty Regional Council and the Rotorua Lakes Council for Additional Funding. Currently $6.5m from MfE and $.75m from RLC.
That the Committee look at ways of bringing the project forward Including Lump Sum payments and early rating.
That there be a community update following the receipt of the CIA.
That towards the end of the year, an expression of community support be assessed.

50. Committees Recommendations
That the Reticulation Zone for Lake Tarawera be increased include Te Mu Road, The Landing, The Buried Village and the new Tarawera Walkway carpark.
Recommendation 6
That Council in consultation with community and Maori land owners evaluate the max number of connections to the scheme.

51. Budgets - Estimated Project Budget
FRESHWATER IMPROVEMENT FUND
Year 1
Year 2
(if applicable)
Year 3
Year 4
Year 5
TOTAL
Amount requested from the fund for each hear of the project (excl. of G.S.T.)
$325,000.00
$550,000.00
$3,825,000.00
$8,525,000.00
OTHER CASH INCOME
(excl. in-kind contributions)
Rotorua Lakes Council - to be recovered from Tarawera ratepayers who are scheme beneficiaries
Rotorua Lakes Council – contribution from general rates
$300,000.00
$450,000.00
$0.00
$750,000.00
Total cash income from other sources for each project year (excl. G.S.T.)
$775,000.00
$9,275,000.00
TOTAL PROJECT INCOME
$1,100,000.00
$7,650,000.00
$17,800,000.00

52. Costs Based on a capital cost of $17.8M
Subsidies Received and other income $ M
Community Cost $ 9.275M
At this stage, subject to change no's of connections
Very draft cost per property would be $16,863
Add GST $19,393
Please note: Subject to final costs, variation in property numbers. Contracts are at + or – 30%

53. Timelines

54. Questions