PAG Water and Energy project: 2021 Water benchmark results

2021 Water Benchmark Results

February 2023

Table of Contents

1. Introduction
2. Methodology
   • 2.1 Development of the Data Collection Tool
   • 2.2 Scope of the Data Collection
   • 2.3 Participation
   • 2.4 Notes on the Data
3. Water Benchmarks
   • 3.1 Drenching Benchmarks
     • 3.1.1 Calculation: Drenching per tonne
     • 3.1.2 Calculation: Drenching per bin
     • 3.1.3 Results
   • 3.2 Dedicated Pre-sorter Benchmark
     • 3.2.1 Calculation
     • 3.2.2 Results
   • 3.3 Dedicated Packing Line Benchmark
     • 3.3.1 Calculation
     • 3.3.2 Results
   • 3.4 Cold Storage Benchmark
     • 3.4.1 Calculation
     • 3.4.2 Results
   • 3.5 Ablutions, Canteens & Offices Benchmark
     • 3.5.1 Calculation
     • 3.5.2 Results
   • 3.6 Overall Packhouse Index
4. Water Usage Profiles
   • 4.1 Results
   • 4.2 Variation in Water Use Profiles
5. Year-on-Year Comparison of Water Use Benchmarks
6. Water Management Practices
   • 6.1 Flume Technology Age
   • 6.2 Flume Water Management
     • 6.2.1 Standard Water Management Processes
       • 6.2.1.1 PH Management
       • 6.2.1.2 Chlorine Management
     • 6.2.2 Cumulative Flume Water Holding Capacity
     • 6.2.3 Flume Water Drainage Cycle
     • 6.2.4 Flume Cleaning Processes
   • 6.3 Water Saving and Water Treatment Methods
     • 6.3.1 Flume Water
     • 6.3.2 Rainwater
     • 6.3.3 Drenching
     • 6.3.4 Pre-sort/Packing Line
     • 6.3.5 Cold Storage
     • 6.3.6 Ablutions, Canteens and Offices
     • 6.3.7 Wastewater Treatment Method
7. Conclusion
8. Recommendations

Introduction

In 2017, Blue North Sustainability was contracted by the Packhouse Action Group (PAG) to conduct a study on the water risks faced by pome fruit packhouse and cold storage operations and provide water consumption benchmarks for these facilities. Since then, Blue North has concluded three more rounds of benchmarking (Phases 2, 3 & 4).

This report concludes the fifth phase of this project and includes data from January to December 2021. The objectives of the fifth phase were to:

• Replicate the water use benchmark study from previous phases
• Increase packhouse participation
• Provide a year-on-year comparison of water use in packhouse and cold storage operations
• Collect more detailed data around drenching and hybrid pack lines
• Collect more data on water recycling practices

This report presents the results from Phase 5 (2021 data) and compares them to previous phases. Electricity benchmark results were compiled in a separate report.

Methodology

Outreach was made to previous and potential new participants via phone or email. New packhouses were offered onboarding sessions; previous participants were offered training in the latest data collection tool.

2.1 Development of the Data Collection Tool

• Additional fields for number of bins drenched, hybrid pack line water use, and wastewater treatment method.
• Data was sense-checked and anomalies discussed with participants.

2.2 Scope of the Data Collection

Five areas in pome fruit packhouses were benchmarked:

• Drenching (fruit or bins)
• Dedicated pre-sort line
• Packing lines (mainly flume water use)
• Hybrid line (pre-sort and packing simultaneously)
• Cold storage (RA and CA facilities, mainly cooling tower water)
• Ablutions, canteen & offices (staff water consumption)

2.3 Participation

• 23 packhouses invited; 9 provided data.
  • Four have participated since the start, three since phase 3, two since phase 4.
  • Main reasons for non-participation: limited capacity for data collection, data quality concerns due to lack of metering or allocation issues.

2.4 Notes on the Data

• All datasets for Phase 5 correspond to the 2021 calendar year.
• Packhouses are anonymised (A to M). Packhouse K could only provide total water consumption.
• Caveats are acknowledged in the report.
• In figures, blue bars = accurate/metered data; yellow bars = estimated/calculated data.

Water Benchmarks

3.1 Drenching Benchmarks

3.1.1 Calculation: Drenching per tonne

Drenching water consumption (m³) x 1000 / Tonnes of pome fruit drenched

Unit: Litres per Tonne of pome fruit drenched

3.1.2 Calculation: Drenching per bin

Drenching water consumption (m³) x 1000 / Number of pome fruit bins drenched

Unit: Litres per bin of pome fruit drenched

3.1.3 Results

• Only packhouses with drenching data shown.
• Some water consumption values estimated due to insufficient metering.
• Notable: Packhouse A used nearly twice as much drenching water per tonne as Packhouse M (metered data).
• Variation attributed to lack of metering, record keeping, and different drenching protocols.

3.2 Dedicated Pre-sorter Benchmark

3.2.1 Calculation

Pre-sort water consumption (m³) x 1000 / Tonnes of pome fruit for dedicated pre-sort line
Unit: Litres per Tonne of pome fruit for a dedicated pre-sort line

3.2.2 Results

• Only packhouses with a dedicated pre-sort line shown.
• Only Packhouse M provided metered data; others are estimates.

3.3 Dedicated Packing Line Benchmark

3.3.1 Calculation

Flume & pack floor water consumption (m³) x 1000 / Tonnes of pome fruit packed

Unit: Litres per Tonne of pome fruit packed

3.3.2 Results

• Many packhouses’ data estimated due to insufficient metering.
• Notable: Lack of metering at packing lines is a concern for data accuracy.
• Recommendation: Industry meter campaign/standard, awareness, training, and affordable recycling technology.

3.4 Cold Storage Benchmark

3.4.1 Calculation

Cold storage water consumption (m³) x 1000 / (CA & RA Tonne.Days)

Unit: Litres per Tonne.Day of fruit stored

• Tonne.Days = Tonnes stored × number of days stored

3.4.2 Results

• Water consumption of some packhouses estimated due to insufficient metering.
• Notable: Packhouse A uses harvested rainwater and defrost water for refrigeration plant.

3.5 Ablutions, Canteens & Offices Benchmark

3.5.1 Calculation

Ablutions, Canteens & Offices water consumption (m³) x 1000 / (Staff man days)

Unit: Litres per person per day

3.5.2 Results

• Good quality data (Packhouse A and D): 52–67 litres per person per day.
• High compared to the 50 litres per person per day allowance during the 2017 “Day Zero” drought.
• Recommendation: Awareness, training, and inexpensive recycling technology, especially for ablutions.

3.6 Overall Packhouse Index

• Incorporates water use for all sections, excluding “other” (non-packhouse/cold storage activities).
• Unit: m³ of water per tonne of pome fruit packed
• Most packhouses consumed 1–2 m³ of water per tonne of fruit packed in 2021.

Water Usage Profiles

4.1 Results

• Figure 8 displays the percentage of water consumed by different areas/activities in each packhouse (excluding “other”).
• Packhouse K could only provide total water use; profile not determined.

Table 1: Summary of Packhouse Data Quality

4.2 Variation in Water Use Profiles

Large variation attributed to:

• Lack of metering (thus estimations)
• Metered consumption not allocated to specific areas (“crow’s nest” piping)
• Lack of or errors in water consumption records
• Use of different types of flume technology
• Application of different water recycling technologies

Year-on-Year Comparison of Water Use Benchmarks

• Benchmarking supports target setting and year-on-year comparisons.
• Only packhouses participating in Phase 5 and at least one other phase are shown.
• For packing line and cold storage, use Packhouse A’s data over all years.
• For ablutions, offices, and canteens, use Packhouse A’s results for 2018–2021.

Trends:

• Upward trend in water consumption from 2018–2019 (lifting of “Day Zero” restrictions).
• 2021: Packing line water use decreased; cold storage, ablutions, canteens, and offices increased compared to 2020.
• Overall, most packhouses show a decrease in water consumed per ton of fruit packed since 2020.

Water Management Practices

Packhouses were surveyed on water reuse technologies and practices.

6.1 Flume Technology Age

• Flume technology age is split between more than and less than ten years old.

6.2 Flume Water Management

6.2.1 Standard Water Management Processes

PH Management:

• Four of nine packhouses monitor pH regularly.
• Three have no pH management.
• One manages ORP (Oxidation Reduction Potential) via an external company.
• One measures borehole water pH annually.

Reported acceptable pH levels:

• 7.0
• 7.0–7.5
• 6.5–7.8

Chlorine Management:

• Seven of nine monitor chlorine levels regularly.
• Corrective actions taken as needed.
• One uses chlorine dioxide instead of chlorine.

Reported acceptable chlorine levels:

• 20 ppm (infeed flume, pre-sort lines)
• 1–3 ppm (pre-sort flumes)
• 2–5 ppm (dedicated packing lines)
• 75 ppm (pear packing line)
• 50 ppm, 10–30 ppm, 25 ppm (other packhouses)

6.2.2 Cumulative Flume Water Holding Capacity

• Ranges from 15–685 m³ (average: 296 m³)

6.2.3 Flume Water Drainage Cycle

• Five of nine drain 100% of flume water weekly.
• Others: every two weeks, 2–3 times per year, or as needed.

6.2.4 Flume Cleaning Processes

• All use similar methods: drain, broom, wash/rinse with high-pressure water and soap, refill.
• Some add chlorine after refilling.

6.3 Water Saving and Water Treatment Methods

6.3.1 Flume Water

• Four drain to dams (then river or groundwater)
• Two filter via reeds/wetland
• Two use storm drains
• One sends to municipal treatment

6.3.2 Rainwater

• Three harvest rainwater (for condensers, production, gardens, or filtration)

6.3.3 Drenching

• Technologies: perforated grids, glass filters, sand filters

6.3.4 Pre-sort/Packing Line

• Technologies: glass filters, sand filters, UV, carbon filters

6.3.5 Cold Storage

• Two recycle defrost/condensate water

6.3.6 Ablutions, Canteens, Offices

• Biozone sewage treatment, rainwater tanks for drinking water

6.3.7 Wastewater Treatment

• Own sewage plant, municipal facility, wetland filtration, silver bromide solution

Conclusion

• Nine packhouses from Phase 4 returned for Phase 5, indicating value in the process.
• Year-on-year comparisons are valuable for internal discussions and show positive trends in water use reduction.
• Collection of hybrid packing line and water recycling data has improved accuracy.
• More accurate data and splitting of tonnages by line type will improve future benchmarks.
• Water reuse, alternative sources, and wastewater treatment are increasing but not yet widespread.
• Sharing of water recycling technologies is valuable for industry learning.
• Areas of concern: lack of metering, limited data collection capacity, unrecorded meter readings, limited use of renewable water sources.
• Positive trend: more packhouses are installing meters for accurate measurement.

Recommendations

• Understand and address reasons for metering and data recording issues.
• Encourage sharing of current and planned water efficiency projects.
• Split fruit tonnages by line type in future data collection.
• Include questions on preventative maintenance (leak detection and repair).
• Collect details on drenching protocols.
• Launch an industry meter campaign/standard.
• Encourage participation through recognition initiatives (e.g., “water heroes” campaign).
• Solicit suggestions to improve data collection tools and processes.
• Implement good water management practices:
  • Metering and regular record-keeping
  • Formal water policy and management plan
  • Water reduction targets
  • Staff training on water efficiency
  • Use of alternative water supplies (rain, ground, surface)
  • Reuse water where possible (e.g., production water for floors, handwashing water for toilets, pump seal/defrosted/condenser water to cooling tower make-up tank)
  • Treat and reuse wastewater
  • Maximise cooling tower cycles of concentration
  • Longer retention of drenching/flume water
  • Regular inspection and repair of leaks/equipment
  • Use efficient fittings and technologies (flow restrictors, tap aerators, auto-stop sensors, automatic shut-off valves, waterless urinals, dual flush toilets, etc.)