Case Study: Low-Flow Toilets
Conducted by: Massachusetts Water Resources Authority (MWRA)
How restaurants can save water and cut costs by replacing high-flow toilets with low-flow toilets
Background
In the early 1990s, MWRA’s Industrial, Commercial, and Institutional (ICI) Water Management Program conducted surveys for varying sizes and types of food service establishments.
These restaurants ranged from 85 seats to 1500 seats. They served an average of 2000 to 40000 meals per week
Their water consumption ranged from under 1 million gallons to 13 million gallons per year
That’s an estimated 6 gallons per meal to 29 gallons per meal
Their goal was to help these businesses improve their water efficiency and, therefore, cut their operational costs
It is important to note that the water + sewer rates of this case study are based on 1993 figures.
Water costs in 2020 are about 5.7 times the 1993 rate
Results
Restaurants can replace high-flow toilets + urinals with low-flow models:
The low-flow toilets use 1.6 (or less) gallons per flush
The low-flow urinals use 1.0 (or less) gallons per flush
By replacing 17 toilets and 7 urinals with low-flow models, a restaurant can save 1.1 million gallons of water per year
In 1993, the restaurant would’ve saved about $8500 with the project costing only about $6700
So, the restaurant would see a payback in around ten months
With inflation increasing today’s energy + water costs, even more money would’ve been saved