Dairy Crest Hanworth - Case study: Reducing water use

“We are already committed to continuous improvement of our environmental performance through our accreditation to ISO 14001. However, we see the FHC as a further impetus to driving down our usage of this valuable environmental resource.”

Ann Lovering - Group Environmental Manager, Dairy Crest


What have we done?

Dairy Crest Having joined the FHC, Dairy Crest undertook a benchmarking exercise across its sites. This identified that the Hanworth site's water use per tonne of milk processed was higher than that at a similar site in the group. To investigate, an exercise was carried out on key items of equipment at the site, which showed that the bottle washers were using significantly more water than their designed usage.

The jet bars on both bottle washers had jet nozzle damage and wear, increasing the orifice sizes. This resulted in the bottle washers using a considerably higher amount of water, with the machines running out of balance.

It was proposed that all 64 jet bars and 1,250 jets be changed for new stainless steel versions on both bottle washers. The project costs to achieve this were £57,000.

When the jet bars were replaced, a 5,502 m3 per month water reduction was realised (on a like for like production volume), equating to 66,024 m3 per year water and effluent savings. A reduction in steam use of 166 tonnes per week was also achieved, with the total savings estimated at £200,000 per year.

Water savings seen since 2007

  • 8% relative water savings across the business;
  • 16% reduction in m3 of water used per tonne of milk processed at Hanworth.

How joining the FHC helped

Joining the FHC focused Dairy Crest's attention on water usage. The company has been monitoring water usage at production sites for a number of years, but benchmarking between sites was not regularly carried out. Joining the FHC acted as the trigger to ensure this was done.

At the Hanworth site, there had been a gradual increase in the water volume used to process a tonne of milk. Benchmarking identified that the site was performing relatively poorly and, therefore, a detailed water balance exercise as recommended by the FHC was carried out. This identified the potential benefits of carrying out the work.

More information

This case study istaken from the The Federation House Commitment - Progress Report: 2009 published in July 2009.