Contents

Reviews

In accordance with 21 (1) (a-c) of the Otago Regional Plan for Water:

This effluent plan was prepared in June 2026 and will be reviewed by June 2027 with the results noted in this section with changes recorded automatically.  The contents of this Effluent Management Plan are available to the regional council on written request.

Location and Ownership

In accordance with 21 (2) (a-e) of the Otago Regional Plan for Water

The physical location of the farm where the effluent system is located is 115 Maheno-Kakanui Rd and the effluent is applied to the same address. The dairy shed is located on Maheno-All Day Bay Rd. Refer to the legal descriptions below for full details.

Farm Owner

Waitahanui Farms Ltd

115 Maheno-Kakanui Rd, 

Maheno 

9495

rossrnz@hotmail.com

Person in Charge

Ross Robertson
0210 232 7220

Waitahanui Dairy Farm

115 Maheno-Kakanui Rd

Legal Description
LOTS 1-3 DP 421 PT CLOSED RD INTERSECTING SECS 72 73 SECS 68 72 PT SEC 69 BLK IV OTEPOPO SD
SEC 1 SO 24607

Existing Consents

RM13.062.01.V1 To discharge odour to air for the purpose of operating a dairy effluent pond.
Expires 1/3/2048

RM22.645.01 & .02 To discharge contaminants to land and air for the purpose of undertaking intensive winter grazing.
Expires 9/12/2032

RM23.280.01 & 02 To discharge odour to land and air for the purpose of disposal of animal effluent.
Expires 9/6/2033

RM24.036.01 To take and use surface water as primary allocation from the Kakanui River for the purpose of irrigation.
Expires 22/2/2035

Map

In accordance with Schedule 21 (2) (e) of the Otago Regional Plan for Water.

Effluent Discharge Area: 90.76ha through pivot, tanker, K line and pods.

Two solid holding ponds with end weeping walls, into a liquid holding pond with a rotating screen for aeration.

From the pond the effluent can be pumped directly to the irrigators.

No effluent is to be discharged within:

• 50m of any surface watercourse.

• 50m of any subsurface drainage.

• 100m of any water abstraction point.

• 200m of place of dwelling or assembly not on the property.

Cows: 1134

Soils

In accordance with Schedule 21 (2) (e) (iv) of the Otago Regional Plan for Water

Soil Types and Risk Profiles

Click here to access the S - Map for Waitahanui Farms. The effluent application area consists mainly of Timaru soils which are high risk FDE Category C land. There are also some Pukeuri soils which are high risk FDE Category B land on the river flats. According to Dairy NZ industry best practice the maximum effluent irrigation depth allowed is 10mm when a soil water deficit is identified that is greater than the application rate although this increases to 25mm for high rate tools on the river flat. This is achieved by application using low rate tools as the first option, specifically pivots, K Line and large effluent pods which can apply a custom amount depending on how long it runs in the same spot or how the pivot is set. Effluent tankers are not currently used but they are a high rate option.

Bucket tests are used to verify application rates and soil moisture deficit is determined a minimum of 24 hours after rain. The application rate must not result in exceeding Field Capacity.

• Timu_1a.2

  • Moderately deep silt loam.

  • Imperfectly drained.

  • High profile available water (59mm).

  • FDE risk category C.

Subsurface Drains

No subsurface drains are known in the effluent area.

Critical Source Areas

Critical source areas are excluded from the effluent application area as shown on the map above.

Operational Procedures and Maintenance

In accordance with Schedule 21 (2) (f) of the Otago Regional Plan for Water

The effluent pump is maintained monthly as part of the dairy shed inspection. For major issues that can't be repaired in-house contact Waterforce on 03 437 2210.

Electrical issues are to be referred to an electrician.

All maintenance and repairs are recorded in the Irrigation Maintenance record and the standard methods for operating the system are in the Effluent Procedures displayed in the cow shed.

ORC Fact sheets provide guidance for staff.

Risks

• • All paddocks have slopes which can cause potential run-off. 

  • Water troughs to be avoided.

  • Effluent area has been designed to reduce the risk of neighbours experiencing odour.

  • Effluent is not to be discharged within 150m of Brookstead Rd in Westerly conditions.

Solids

• Solids are spread annually, and cannot be spread on the same area more than once every two months, preferably by incorporating into cultivation of land.

• Solids are not spread onto land when the soil moisture exceeds field capacity; or within 20 metres of waterways. 

• Solids are also not spread where previous applications are still visible on the ground, or where soil moisture exceeds field capacity (a reading of 39% VWC on the soil moisture meter).

• Hazardous substances, hazardous waste and human effluent is not to be added to the effluent system.

Inspection, Monitoring and Reporting

In accordance with Schedule 21 (2) (g) of the Otago Regional Plan for Water

Inspections

Inspect the system for leaks, ponding and run off each time the pump is started up and in between shifts. Weak points are at hydrants and hoses. Check for kinks in hoses, holes, leaks or blowouts. Check that the nozzles are under pressure, the irrigator is operating normally. Leaks, ponding, run off and flow through drainage can cause the effluent to enter a waterway which must not occur.

As part of the monthly shed inspection check the area below the storage pond for wet patches, areas of grass that are greener than the grass surrounding it or any other signs of leaking from the pond. Include a check of the stone traps to ensure they aren't becoming blocked.

Bucket tests are completed annually on the irrigators to verify application depth and rate.

Monitoring

In addition to the checks after start up staff are to check the same components while the effluent is running if they are passing the irrigator during the day.

All staff are to report any odour from the system to the farm owner if it reaches the farm boundary, or if any complaints are received about the effluent system including odour.

Reporting

When a leak, ponding or run off are discovered the pump must be turned off immediately and the fault reported to the farm owner within half an hour. Where possible the problem should be fixed immediately and recorded.

Effluent applications are recorded in the dairy diary and reported at audits for NOIC and ORC.

Pond Drop Test Records

In accordance with Schedule 21 (2) (h) of the Otago Regional Plan for Water

The storage pond is a permitted activity.

Date of last test: 

Date next test is due: 

Drop Test Report
Visual Inspection
DESC

Contingency Measures

In accordance with Schedule 21 (2) (i) of the Otago Regional Plan for Water

The effluent system has several measures to prevent discharges to water:

• Staff training

• Monitoring

• Low pressure/high flow automatic pump cut out.

• Low rate application systems.

• Large storage pond. We never know when we will need to pump to storage or when we can empty the storage so we use every opportunity to drain effluent out of storage and apply to the paddocks. If there is effluent in storage and the soil has the appropriate soil water deficit to irrigate then emptying storage is a priority.

Leak Response

In accordance with Schedule 21 (2) (j) of the Otago Regional Plan for Water

• When a leak, ponding or run off are discovered the pump must be turned off immediately and the fault reported to the farm owner within half an hour. Where possible the problem should be fixed immediately and recorded.

• If a leak is detected in the effluent storage pond it must be emptied as soon as possible within the limits of the soil water deficit and the leak found and repaired.

Effluent Complaint Record

A register of effluent complaints must be available to the Otago Regional Council on request. If a complaint is received use this form to collect the following information:

(a) The date, time, location, and nature of the complaint

(b) The name, phone number and address of the complainant – unless the complainant elects not to supply, this information

(c ) Action taken by the consent holder to remedy the situation and any policies or methods put in place to avoid or mitigate the problem occurring again.