Contents

Reviews

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

This effluent plan was prepared in November 2023 and will be reviewed by November 2024 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 6 Willowview Road, Maheno and the effluent is applied to the same address. The dairy shed is located at 190 Island Stream Rd. Refer to the legal descriptions below for full details.

Land Owner:

D.J. and S.E. Mathieson
3971 Hampden-Palmerston Rd
RD2 Palmerston 9482

Person in Charge:

Liz Hamilton
190 Island Stream Rd,
Maheno
027 568 8942

Legal descriptions:

LOT 1 DP 387370 LOTS 1-2 DP 387370 PT SECS 19 20 21 BLK VI PT SEC 22 BLK VI LOT 1 DP 12575 LOTS 1-2 DP 10556 PT LOTS 1-2 DP 2879 LOTS 2 DP 476007 LOT B DP 1097 PT SEC 1 OF 22 BLK VI OTEPOPO SD  

Existing Consents

• Surface Water Take Permit 2010.060

Map

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

Effluent Discharge Area: 78ha through irrigation system. K Lines must not be within 50m of Island Stream while discharging effluent.

The system features gravity feed from the shed through a stone trap to the settling pond.

From the settling pond the the effluent transfers to the storage pond from where it is injected into the irrigation system.

Safety features include a timer to run the effluent for only three hours per twelve hour K-Line pull and a low pressure cut-off in case of blow out.

No effluent is to be discharged:

• Across the farm boundary. Effluent is not to be applied when wind conditions cause it to leave the property.

• within 50m of any surface watercourse

• within 5m of any subsurface drainage or open drain  .

• within 5m of any surface water abstraction point.

• within 100m of any bore. Bore J42/0060 on the property no longer exists.

• within 150m of place of dwelling or assembly not on the property except as consented - don't apply effluent when wind conditions will carry odour to neigbours.

Cows: maximum 420 cows milked twice per day. 

The latest effluent map below shows effluent risk, critical source areas and waterways. Other relevant maps are located in the maps folder of the Farm Environment Plan folder.

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 The Willows. Waitohi soils are the majority of soils which are high risk FDE Category B. 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. This is achieved by application using a permanent soil moisture probe to determine soil moisture deficit, and then using a timer to apply effluent across a large area simultaneously through the irrigation system for a maximum of three hours at a time to ensure application depth doesn't exceed soil moisture deficit.

• Waitohi Soil

  • Silt over clay.

  • Poorly drained.

  • Sufficient profile available water (54mm).

  • FDE risk category B.

Subsurface Drains

No subsurface drains are in the effluent area. There are various open drains which are mapped as critical source areas.

Critical Source Areas

Numerous critical source areas are located throughout the farm and cannot be excluded from the effluent application area entirely. However, open drains can be avoided entirely and where a swale is at risk of ponding or run off the individual pod will be turned off to minimise the risk. Additionally, effluent is not applied unless there is a soil moisture deficit.

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 the electrician or Waterforce. Always listen for changes in the sound while it is running.

Electrical issues are to be referred to Waitaki Electrical on 0800 277 244.

All maintenance and repairs are recorded in the Irrigation Maintenance record book.

ORC Fact sheets provide guidance for staff in addition to training in accordance with this template. Only trained staff are to operate the effluent system, however all staff are responsible for reporting any issues. 

Risks

• • Most paddocks have Critical Source Areas which can cause potential run-off. Individual pods are shut off to reduce run off and pooling risk. Effluent is not applied unless a suitable soil moisture deficit is measured.

  • Water troughs to be avoided to mitigate risk of contaminating stock drinking water.

  • Effluent infrastructure has been designed to reduce the risk of neighbours experiencing odour by using K-Line which spreads low to the ground with low flow rates at each sprinkler for less effect from the wind. Effluent is not spread in wind conditions that will cause effluent or odour to leave the boundary.

  • Island Stream bisects the entire property so effluent is applied up to the fences and no closer than 5m from the stream. Individual pods are shut off to reduce run off and pooling risk where needed. Effluent is not applied unless a suitable soil moisture deficit is measured.

  • Three public roads run around three sides of the farm. The Willows reduces the risk of the public experiencing odour on these roads by using K-Line which spreads low to the ground with low flow rates at each sprinkler for less effect from the wind. Effluent is not spread in wind conditions that will cause effluent or odour to leave the boundary.

  • Flooding occurs occasionally. Storage is kept as empty as possible at all times within the limits of soil water deficit to ensure that maximum freeboard is available to store effluent in the event of a flood. 

Operation

1. Establish there is a soil moisture deficit using the soil moisture meter. This doesn't need to be done every time - only if there has been rain since the last reading. Do not apply effluent if there is already ponding, if cows will graze it within 24 hours, or if the ground is frozen or covered in snow.

2. Select application area to maximise an even rotation around the entire effluent area then check that effluent will not enter a waterway - including over land, directly or indirectly or through storm water or pipe. Only apply effluent within the effluent area on the map above.

3. Consider wind direction to prevent effluent spray or odour leaving the boundary. Do not apply effluent within 50m of the boundary upwind of the boundary in more than fifteen knots of wind.

4. Check the irrigators are set up, including that feeder hose bends have a radius of 1.5m to prevent kinking.

5. Start pump. Listen for unusual noise which may indicate a fault.

6. Inspect system as detailed below.

7. Record effluent application.

Minimisation of Effluent

• Limit flow of nozzles in the shed to a minimum.

• Pre-wet concrete ahead of milking to speed up hose down at the end.

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, or the farm boundary. 

• 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 the hydrants and the feeder hose. Check for kinks in the hose, holes, leaks or blowouts. Check that the nozzles are not blocked and are under pressure. 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 drain 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. Check for cracks in concrete or other signs of deterioration that may lead to leaks.

Bucket tests are completed on the irrigators at least once every three years to verify application depth and rate. Application rate can be adjustedby changing the timer. 

• 2023 Bucket tests 

Monitoring

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

All staff are to report any odour from the system to Liz 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 repaired before effluent is pumped again. Where possible the problem should be fixed immediately and recorded in the book.

For major issues that can't be repaired in-house contact Waterforce.

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

Pond Drop Test Records

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

Date of last test: 16th July 2024

Date next test is due: 16th July 2029

Storage meets permitted activity criteria. 

Dairy Effluent Storage Calculator

Visual Inspection

Drop Test Report

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

• Timers

• Low pressure cut-out

• Enlarged 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 take 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.

• Low water use creates less effluent with greenwash in the yard and recirculated cooler water for the wash down hoses.

• Large effluent discharge area per cow reduces the nutrient discharge per hectare.

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 repaired before pumping recommences. Where possible the problem should be fixed immediately and recorded in the book.

• For major issues that can't be repaired in-house contact Waterforce.

• 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.