Industry water benchmark study helps manage risks

By Eddie Vienings and Dianca Yssel

South Africa is a water scarce region of the world, receiving 40% less precipitation than the global annual average. The implications of this have become clearly evident in recent times – with almost all our available water supply already allocated, South Africa has very little margin to play with.

Challenges arising from chronic water scarcity are further exacerbated by generally sub-optimal water resource governance, resulting in issues of contamination as well as inefficiencies in storage, conveyance and use.  Given that agriculture is in many cases the largest water user in a catchment, this presents a significant risk across agricultural value chains, from the farm level to packhouses and cold storage facilities.

The Packhouse Action Group (PAG) Water Benchmarking Project was initiated in recognition of the need to identify and manage water-related risks at the packhouse and cold storage levels in pome fruit value chains.

The PAG steering committee initiated phase 1 of the project in 2017 and Blue North Sustainability was appointed as project managers.

Phase 1 objectives included:

• identification of key water-related risks;
• a water consumption benchmark study to highlight areas where packhouses can save water;
• developing a methodology for the identification and management of water-related risks for pome fruit packhouse and cold storage operations; and
• encouraging industry knowledge sharing.

In 2019, the PAG approved a second phase for this project.  The objectives of the second phase were to:

• replicate the water use benchmark study undertaken in phase 1;
• provide a year-on-year comparison of water use in packhouse and cold storage operations; and
• collect information on water management practices.

In 2020, the PAG approved a third phase for this project. The objectives of the third phase were to:

• replicate phase 2 objectives;
• Increase packhouse participation; and
• collect more detailed information on packing line water management practices.

The project commenced in 2017 and is now in its fourth year.  The most recent phase of data collection was conducted between 23^rd October and 1st December 2020 to coincide with the packhouse “off season”.

Data was collected in three packhouse areas:

• Packing Lines – This included all packing line water consumption, of which flume water use made up the majority.
• Cold Storage – This included Regular Atmosphere (RA) and Controlled Atmosphere (CA) facilities. Cooling tower water consumption made up the majority of cold storage water consumption.
• Ablutions, Canteen & Offices – This included all staff water consumption.

One of the main areas for improvement identified through the course of the project has been data availability and accuracy.  In some cases, packhouses have had no water metering or record keeping in place or not all water consuming sections or processes are metered, creating challenges when allocating water use to specific packhouse processes and sections. The water reticulation system in some of the older packhouses has also proved challenging; they can be something of a “black box” due to several packhouse modifications and extensions over the years. The project was established for this purpose and the findings have formed the basis of continuous improvement processes; we’ve witnessed improvements in  water metering and data recording within the first year of packhouses participating in the project.

Ten packhouses participated in the latest round of the project and we have received the commitment from 3 more packhouses who will participate in the 2021 data collection round.

Figure 1 (below) shows the anonymised 2019 results for the packing line section. The two packhouses in blue passed the data sense checks for this section and the packhouses in yellow indicate some level of data incompleteness. As can be seen, water consumption in packing lines varied between 264 and 663 litres per ton packed. The large variances in this figure suggests opportunities for, in some cases significant, water use efficiency improvements.

Figure 2 (below) shows the anonymised 2019 results for the cold storage section.  Five packhouses provided data for their cold storage sections that passed the data quality sense checks. Water consumption from these checked datasets varied between 3 and 14 litres of water per ton of pome fruit stored for one day. The variation was even larger when considering the whole sample. This large variation in results again indicate significant water saving potential in the cold storage sections of many packhouses.

Figure 3 (below) shows the anonymised 2019 results for the ablutions, canteen, and offices. Results from the two packhouses that passed the data quality sense check varied between 38 and 59 litres per person per day. A good benchmark to consider here is the City of Cape Town “day-zero” water budget of 50 litres per person per day.  Both the variability in results as well as the “day zero” target point to opportunities for improvement in this aspect of packhouse water management.

The saying that “you can only manage what you measure” comes to mind! This is so true for water consumption in a packhouse. The project has identified sections where packhouses can improve metering and water data recording. Furthermore, the large variation in results point to technology and operating procedure changes that packhouses can make in specific areas to improve their water management and reduce their water consumption.

Interestingly, the results indicate an increase in water consumption in all areas since the project was started in 2017. One possible explanation for this apparent increase that has been put forward was the relaxation of water restrictions after the “day-zero” crisis was averted. The ongoing process of data quality sense checking is aimed at confirming these consumption trends.

Water is a critical resource in agricultural supply chains. Armed with the valuable insights provided by the PAG Water Benchmarking Project, packhouse managers have a heightened understanding of where, for what purpose and how much water is being used in their operations and are better equipped to measure, manage and improve the use-efficiency of this critical resource.

The full report contains more information on packhouse water use profiles, packing line water management practices etc. and can be requested from Hortgro.

Please contact Eddie if you are interested in participating in the next round: eddie@bluenorth.co.za