Leaky effluent ponds? Prove it!

Most dairy effluent storage pond owners believe that their ponds are not leaking, particularly those that have been synthetically lined. However, even with synthetic lining, it is not possible to be sure that the pond is not leaking without carrying out a test. Therefore, it is important for dairy farmers to have their effluent storage ponds tested to ensure that they are not leaking.

One of the drivers for proving that effluent storage ponds are not leaking, is the need for farms to operate at a minimum of Good Management Practice (GMP). Ideally the farming operation should be operating at better than GMP.

GMP is a set of standards and guidelines that aim to ensure that farms are managed in a sustainable and environmentally responsible way. One of the key requirements of GMP for dairy farms, is that effluent storage facilities must be sealed and maintained to ensure the containment of effluent. Therefore, it is essential for dairy farmers to test their effluent storage ponds to ensure that they are meeting the GMP standards.


The need for effluent storage pond testing may not always be initiated by the Regional Council. Sometimes this can also be requested by the irrigation scheme, dairy company or can be as a result of a Farm Environment Plan (FEP) audit. These requests are becoming more frequent as the importance of good farming practices and environmental sustainability increases.

In the past, especially when FEP’s were first being introduced, some farmers questioned the need for environment plans. They considered that they were already doing a good job of farming in a responsible and environmentally friendly way. However, it soon became apparent that it is no longer sufficient to ‘be’ a good operator; farmers must now ‘prove’ that this is the case. This ‘proof’ of good practice and sustainable actions does not stop at the farm, this is also now being required by companies within the supply chain and from the markets that they serve. At the farm scale, this can be done through the FEP and associated auditing process, and for effluent storage ponds, it can only be done through appropriate testing.

Accurate testing is essential to ensure that effluent storage ponds are meeting the required standards. In Canterbury, the criteria for storage being a permitted activity is that leakage cannot exceed 1mm per day. Measuring leakage in a dynamic environment can be challenging. Whilst the test is being carried out there may be rainfall, evaporation, wind and associated wave action, barometric pressure changes and sometimes even flows into or out of the pond. In these dynamic environments, companies need to be able to measure with sufficient accuracy to comply with industry and regional council expectations. If the pond testing apparatus has recently been upgraded this also helps to increase the degree of accuracy and make the process easier to set up and dismantle. This helps save time, therefore reducing the costs of the testing. 

For more information or to book your test

Christchurch: +64 3 964 6521
Ashburton: +64 3 307 6680
Hastings: +64 6 873 404
Cromwell: +64 27 457 0415

© 2004 - 2022 Aqualinc Research Limited