Water is precious… established Scottish restaurant tells why

• A growing food business zeroed in on a major water waster… toilets
• Fitting passive infrared sensors reduced toilet water use by up to 75 %
• Simple measures reduced water costs by 33 %, saving ~€ 5 600 yearly

Henderson of Edinburgh Restaurant is a Scottish institution serving quality produce from their organic market garden since 1963.

The business has grown and now includes a retail outlet, an organic artisan bakery, a deli shop, a table-service bistro, a café and a restaurant with over 50 people employed.

At the restaurant, water is used for cooking, cleaning, dishwashing, vegetable washing, toilets and taps, and in food and drinks. The amount the company paid for water services was considered excessive and costly.

The restaurant owner turned to Zero Waste Scotland (ZWS) to identify ways of reducing water consumption and, in turn, saving money. A ZWS expert advised Henderson’s to establish a water mass balance to understand where and how much was being used in order to identify key areas for improvement.

For example, reading the water meter at the end of business on Saturday and then again on Sunday morning would identify leaks or wastage outside of business activities.

Toilet cisterns at the premises had a capacity of 9 litres and it was estimated that toilet flushing cost over £ 2 500 (~€ 2 800) a year. Placing low-cost devices in the cisterns to reduce the flush volume to 6 litres without compromising flush efficiency, reduced annual water use by 350 m3.

The restaurant’s two urinals had no flush control and it was estimated they used 368 m3 of water per year

Key results

A number of options were considered to reduce the amount of water used by the urinals (e.g. waterless urinals and timer controls). The decision to fit passive infrared sensors reduced water use by up to 75 %.

Following these simple measures the restaurant managed to reduce its water costs by 33 %, thus reaching annual saving £ 5 000 (~€5 600).