Water savings in restaurants: the valve using nearly a third of the kitchen's water

Water savings in restaurants start at the dishwashing sink: the pre-rinse spray valve, which removes leftovers from plates before the dishwasher, can account for nearly a third of the water in a commercial kitchen, according to the US Environmental Protection Agency (EPA). Replacing the valve, scraping plates before rinsing and retiring the hose from cleaning solve most of the waste. At La Patria Café e Bistrô, in Campos dos Goytacazes, Brazil, finding the problems and training the team delivered a 35% saving in consumption.

In short:

• The pre-rinse spray valve can take nearly a third of a kitchen’s water. Old ones run at up to 17 litres per minute; those sold in the United States today use at most 4.8.
• One hour a day of an old valve uses about 1,000 litres; with an efficient one, under 300, using the EPA’s calculation.
• A wash-down hose discharges 19 to 26 litres per minute; a mop bucket takes 38 to 57 litres.
• ENERGY STAR dishwashers, ice machines and combination ovens use at least 10% less water and energy, according to the EPA.
• At La Patria Café e Bistrô, the diagnosis and staff awareness delivered a 35% saving.

Where does a restaurant use water?

In the kitchen, first of all. According to the EPA, the largest water uses in restaurants are kitchen equipment and processes, followed by washrooms. Inside the kitchen, almost everything is washing:

Point	What it uses water for	Where the waste is
Pre-rinse spray valve	Removing leftovers from plates, pans and trays before the dishwasher	Old high-flow valve, trigger locked open
Dishwasher	Washing and sanitising	Running half empty, old model
Prep sinks	Washing food and utensils	Tap open throughout preparation, thawing under running water
Floor cleaning	Washing the kitchen, bin area and cold rooms	Hose running instead of squeegee, mop and bucket
Ice and equipment	Ice machine, dipper well, stoves with running water	Inefficient equipment or left on unused
Washrooms	Customers and staff	Toilets with a trickle, taps without self-closing

Why is the pre-rinse spray valve the kitchen’s biggest waste?

Because it stays open all day and, in old models, pours out a lot of water per minute. The EPA estimates that it can account for nearly a third of the water in a typical commercial kitchen and that kitchens tend to use it for up to 200 minutes a day. The calculation is simple: flow rate times minutes of use times days of operation. For one hour of use a day and 26 days of operation a month:

Valve	Flow rate	One hour a day	Per month
Old, made before 2005	Up to 17 litres per minute	1,020 litres	26,520 litres
Made between 2005 and 2019	Up to 6.1 litres per minute	366 litres	9,516 litres
Current, within the 2019 US rule	Up to 4.8 litres per minute	288 litres	7,488 litres

Replacing an old valve with an efficient one saves, in this example, almost 20,000 litres a month. And because pre-rinse water is usually hot, the gas or electricity bill falls too. According to the EPA, replacing a valve of 6.1 litres per minute or more with an efficient one pays for itself in under a year in most kitchens.

When choosing and using the valve:

• Choose the spray force for the job. A kitchen with light dishes works with a gentler spray, which uses less; pans with baked-on residue need a stronger one.
• Do not lock the trigger open. The continuous-spray clamp, misused, leaves water running between one plate and the next.
• Adjust the hose height. A valve too high or too low makes staff prefer the tap, which uses more.
• Clean off scale and look for leaks. Do not drill out the nozzle to increase the spray: that increases consumption. If it cannot be recovered, replace it.

What are the 10 measures for saving water in a restaurant?

1. Replace the pre-rinse spray valve with an efficient model, as in the section above.
2. Scrape plates and pans before rinsing. It is the EPA’s recommendation for reducing pre-rinse water and the load on the food waste disposer. In self-service restaurants, a sign asks customers to clear their leftovers.
3. Do not wash dishes with the floor hose. The EPA reserves the hose for floors and counters; dishes go under the pre-rinse spray valve.
4. Clean floors with a squeegee, mop and bucket. A wash-down hose discharges 19 to 26 litres per minute: ten minutes of it use 190 to 260 litres, enough to fill three to almost seven mop buckets. Shut the supply valve when it is not in use, because self-closing nozzles also leak.
5. Run the dishwasher only when full and, when replacing it, choose a certified model, which uses at least 10% less water and energy.
6. Make only the ice that will be used, with an efficient machine.
7. Switch off whatever runs non-stop. The EPA lists dipper wells and stoves that use running water among the equipment to replace or turn off when idle.
8. Thaw in the fridge, not under running water. Brazil’s health regulator, Anvisa, already requires in its food service rule (RDC 216/2004) that thawing be done under refrigeration, below 5 °C, or in the microwave when the food goes straight to cooking. Planning prep takes care of food safety and water at the same time.
9. Look after the washrooms. Self-closing taps, efficient toilets and a monthly dye test: a toilet with a visible trickle wastes 144 litres a day, according to the water conservation manual of Brazil’s National Water Agency (ANA), FIESP and SindusCon-SP.
10. Measure and train. Note the meter reading at opening and closing every day, and agree the rules with the team. Consumption while the restaurant is closed is a leak or forgotten equipment.

How much can a restaurant save?

The result depends on the starting point, but cases show the order of magnitude. Thiago Amorim, owner of La Patria Café e Bistrô, in Campos dos Goytacazes, Rio de Janeiro state, described T&D’s work like this: “They identified the problems and raised people’s awareness, achieving a 35% saving in consumption. They are super competent! They work respecting the company’s rules and routines.”

La Patria’s path is the one that works in any kitchen: find where the water goes, fix what is loss and agree routines with the people who work there. In T&D’s SEA 360º, the ceiling observed in the full programme is a 70% reduction, and each restaurant’s result is calculated against its own baseline.

How do you measure a restaurant’s water use?

Per meal served. The total bill varies with how busy the restaurant is, and consumption per meal shows whether the kitchen became more efficient or just sold less. As an order of magnitude, the kitchen of a public hospital in Brasília, measured by University of Brasília researchers, used about 30 litres per meal. Each restaurant’s number depends on the menu, the service and the dishes.

The roadmap:

1. Baseline: twelve months of consumption, with the number of meals in each month.
2. Daily reading: meter at opening and closing, to separate the working day from the night.
3. Indicator: litres per meal, tracked every month.
4. Review: consumption outside the pattern calls for a walk around the kitchen looking for the locked valve, the forgotten tap or the leak.

The signs of hidden leaks and the full test are in invisible leaks: find them before the bill does, and the roadmap for any business in the guide to water savings for businesses.

How does T&D help restaurants save water?

With SEA 360º, in two phases. Implementation, with no construction work, covers the baseline under the IPMVP protocol, efficiency technology at points of use, electronic leak detection, repairs and team training, one of the points La Patria highlighted. In ongoing management, T&D tracks consumption and delivers monthly reports on financial, operational and ESG performance.

For chains and industrial kitchens, TDRR remote monitoring tracks reservoirs, pumps and hourly consumption, and sends an alert by app, text message or WhatsApp when a unit drifts from its pattern. For restaurants in shopping centres, the food court rules are in water savings in shopping centres.

Frequently asked questions

How much water does a restaurant use?

It depends on the menu, the number of meals and the dishes. The indicator that allows comparison is consumption per meal served. As a reference, the kitchen of a public hospital in Brasília studied by the University of Brasília used about 30 litres per meal.

Is it worth replacing the pre-rinse spray valve?

In most kitchens, yes. According to the EPA, replacing a valve of 6.1 litres per minute or more with an efficient model pays for itself in under a year, through savings in water and in the energy used to heat it.

Can food be thawed under running water?

Anvisa’s food service rule in Brazil, RDC 216/2004, requires thawing under refrigeration, below 5 °C, or in the microwave when the food goes straight to cooking. Planning prep avoids running water and protects the food.

How do you get the kitchen team involved in saving water?

With simple, agreed rules: scrape before rinsing, do not lock the valve open, wash floors with squeegee and bucket and report any leak. At La Patria Café e Bistrô, raising people’s awareness was part of the path to the 35% saving.

Can a small restaurant save water too?

Yes, and with the same measures. La Patria is a café and bistro, and the pre-rinse spray valve, the hose and the washrooms weigh on any kitchen, large or small.

Sources

• EPA WaterSense at Work, section 4.1, Pre-Rinse Spray Valves (2023): weight, flow rates, use time, calculation and payback of replacing the pre-rinse spray valve
• EPA WaterSense at Work, section 4.8, Wash-Down Sprayers (2025): wash-down hose flow rates and cleaning methods that use less water
• EPA WaterSense, Types of Facilities: the largest water uses in restaurants
• EPA WaterSense, Saving Water in Hotels (2016): certified kitchen equipment and equipment that runs water continuously
• Anvisa, Resolution RDC No. 216 of 15 September 2004, in Portuguese: item 4.8.13, thawing
• Santana, L.; Sant’Ana, D. Water end-use analysis in a public hospital in Brasília, Brazil. Engenharia Sanitária e Ambiental, 2023: water use per meal in the hospital kitchen
• Conservação e reúso da água em edificações (ANA, FIESP and SindusCon-SP, 2005), leak loss table, reproduced in Souza et al., XXI Brazilian Water Resources Symposium (ABRHidro, 2015), in Portuguese
• Testimonial by Thiago Amorim, owner of La Patria Café e Bistrô, published by T&D
• T&D SEA 360º and TDRR