Effluent Management Plan

Contents

Reviews

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

This effluent plan was prepared in December 2024 and will be reviewed by December 2025 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 376 Brookstead Rd, Georgetown and the effluent is applied to the same address. Refer to the legal descriptions below for full details.

Land Owner:

Brookstead Ltd
484 Brookstead Road
Oamaru 9491

Person in Charge:

Rhys Hamilton
Ph 0274 317 077

Legal descriptions:

LOT 1 DP 27297 LOT 1 DP 10257 SECS 53-54 PT SEC 52 BLK VI AWAMOKO SD 

Existing Consents

• RM24.754.01 To discharge animal effluent to land and to use an animal effluent system for the purpose of operating an animal effluent system, expires 2035.

• RM23.245.02 To discharge contaminants to land for the purpose of undertaking intensive winter grazing, expires 2028. 

Map

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

Effluent Discharge Area: 160ha (152ha pivot and 8ha fixed grid). 

The system consists of a sand trap draining to a sump with solids separator which discharges into a plastic lined storage pond.  The pond is 2,180 cubic metres. The system discharges primarily by injection through the irrigation system into three of the four pivots, parts of the fixed grid to improve fertility in targeted areas, and in shoulder seasons through pods for an hour at a time.

No effluent is to be discharged within:

• 20m of the farm boundary or further if necessary to prevent spray drift crossing the farm boundary

• 50m of any surface watercourse.

• 50m of any subsurface drainange.

• 100m of any water abstraction point should any be established.

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

Cows: Up to 990 cows milking twice a day peak milk.

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 as relevant the electrician Waitaki Electrical on 0800 277 244, or Ahoy Engineering on 0210 300 944. Waterforce Oamaru can supply parts for self repair.

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

Operation Procedures

Soil Moisture Deficit

Check that Aquacheck data and graph shows adequate soil moisture deficit.

Running Straight Effluent:

• Check Outlet is Open

  • Pivot: tap open and control valve to 'open.'

  • Pods or Fixed Grid: relevant tap open.

Injecting into irrigation:

• Open outlet into irrigation pond.

• Open irrigation tap outlet - water will flow back up the line.

• Start pump

  • Ensure VSD is set at correct setting for application (see below).

  • Prime pump with all taps closed (20-30 pumps).

  • Start pump and stirrer.

  • Slowly open self cleaning screen (green tap).

  • Slowly open blue main tap keeping pressure over 35psi.

• Slowly shut outlet into irrigation pond.

Post Start Checks

• Ensure effluent is being dispersed as intended.

• Ensure pivot valve is on auto.

• Check for leaks or malfunction in the system.

• Monitor system consciously while running to ensure there is no run off.

• Take care not to kink the pod feeder hose - ensure a 3m diameter loop when pulling back. Shift pod approximately 40m each time and prioritise safe placement for both yourself and the environment when considering terrain.

Shut Down

• Turn pump and stirrer off.

• Shut blue main tap at pump.

• Shut all outlet taps (if running straight effluent or not intending to restart).

Recording

• Record application in the hard copy Irrigation Scheduling Sheet. 

Risks

• • All paddocks have slopes which can cause potential run-off. Timers and bucket testing to be used to adjust application depth according to soil moisture.

  • Pivot tracks can cause run off. Position pods away from pivot ruts so the effluent falls at least 5m short.

  • Water troughs to be avoided by pod.

  • Effluent is not to be applied to gully floors.

Note: original controlled copies of all farm Operational Procedures are located here.

Solids

• 1. • Solids are spread periodically as limited by storage, 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.

     • 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 as well as in passing throughout the day. Weak points are at the manifolds, the hydrants and the feeder hose. Check for kinks in the hose, holes, leaks or blowouts. Check that the sprinklers are under pressure and turning normally. Ensure the sprinkler is not located in a swale or siphoning. 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.

Inspections, audits and certificates from North Otago Irrigation Company, Fonterra (QCONZ), and Otago Regional Council are kept on record.

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 at least once a day.

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

Aquacheck data and graph verifies that over application of effluent has not occurred.

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, 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: 22nd June 2022

Date next test is due: 22nd June 2027

Pond Drop Test Report and Graph are available. 

The effluent storage facility also has a Dairy Effluent Storage Calculator and will be checked by a suitably qualified person to ensure permitted activity status.

Visual Inspection

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 (template)

• Monitoring

• Low pressure/high flow automatic pump cut out with Variable Speed Drive.

• Low rate application systems.

• Cooler water is metered and recycled to reduce volume of effluent produced.

• Automated text message timer prevents accidental over watering. It's important not to become complacent and rely on the automation.

• 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.

• Stirrer is proactively used to prevent buildup of solids. Solids are removed manually if needed.

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

• Storm water diversion from the cow shed roof prevents fresh water from unnecessarily occupying capacity in the effluent system during heavy rain.

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.

• For major issues that can't be repaired in-house contact as relevant the electrician Waitaki Electrical on 0800 277 244, or Ahoy Engineering on 0210 300 944. Waterforce Oamaru can supply parts for self repair.

• 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.