Outdoor Use Reduced as Utility Drought Rules Take Effect

SAN LUIS OBISPO, Claif., July 29, 2021 /PRNewswire/ -- Flume, the company that brings connectivity and intelligence to household water usage, today released the quarterly results for the Flume Household Water Use Index, the leading measure of U.S. household water use. The Flume Index shows that western water providers that are implementing drought restrictions are successfully reducing outdoor use during the summer of 2021. Nationally, indoor household water use has largely returned to the levels measured before the pandemic. 

The Flume Household Water Use Index is based on data from tens of thousands of Flume devices that are installed on household water meters across the nation. Flume water use data summaries are reported quarterly.

National Indoor Per Capita Water Use
As seen in Figure 1, Indoor Household Water Use was an average of 46.2 Gallons per Capita per Day (GPCD) in Q2 2021.

In Q2 2021 indoor water use nationally returned almost back to the levels measured before the pandemic, after a period of higher indoor water use during most of 2020 due to COVID-19 restrictions. On a national scale, the lingering impacts on indoor use appear to be small, but there are some regional differences. Water-efficient homes can use 35 GPCD or less, so the Flume data show that additional indoor efficiency potential remains.

Figure 1: Flume Indoor Household Water Use Index - Q4 2019 through Q2 2021.

Indoor Per Capita Use by Metro Area
Indoor per capita use for the 15 most populous Metropolitan Statistical Areas (MSA) in the US was calculated by Flume for Q2 2021. The Philadelphia MSA was the most efficient metro area during Q2, with an average indoor use of 41.0 GPCD. The Phoenix MSA had the highest indoor use per capita in Q2 2021 with an average of 57.5 GPCD.

National Outdoor Household Water Use
Outdoor Household Water Use was an average of 220.4 gallons per household per day (GPHD) in Q2 2021. That is a decrease of 7.8% from Q2 2020 as summertime water use did not ramp up as steeply this year as it did in 2020. The Flume Index shows average outdoor use from households across the US in all climates. Specific information on outdoor use can be seen on the interactive dashboard, link provided below.

The Impact of Watering Restrictions on Outdoor Water Use
According to the weekly U.S. Drought Monitor, as of June 1, 2021, 43.7% of the contiguous U.S. was classified as experiencing moderate to exceptional drought. Cities and states, particularly in California and the southwest, implemented outdoor irrigation restrictions to curb water use and extend dwindling water supplies.

California's Marin Municipal Water District (MMWD) is one provider that has implemented outdoor irrigation restrictions during Q2 2021. With reservoir levels at historic lows, the MMWD board of directors declared a water shortage emergency and adopted mandatory water use restrictions. The goal of MMWD's restriction program is to achieve a 40 percent reduction in water use districtwide. Some of the rules, which have become more stringent over the course of the summer, include limiting spray irrigation to one day a week and drip irrigation to two days per week.

Flume data provides unique insight on the impact of irrigation restrictions on a daily, weekly and monthly basis. Figure 2 shows the daily average outdoor water use in Marin County, the Los Angeles MSA, and the rest of California. While water use across the state and in other cities steadily increased during Q2 2021, outdoor water use in Marin decreased as soon as restrictions were enacted in mid-May. During June 2021, average outdoor use in Marin was less than half that (44%) of the rest of California.

Figure 2: Flume Outdoor Household Water Use in Marin County, Los Angeles MSA, and the rest of California for Q2 2021

"Tracking indoor and outdoor demand separately and in real-time during a drought enables water utilities to adapt their response measures and achieve necessary savings," said Peter Mayer, P.E., Principal of WaterDM - an expert consultant to the water industry for more than 25 years. "A drought is not a static event and Flume provides essential data for making important management decisions."

For More Information
For more information about how Flume collects and analyzes water use data, and for detailed graphs with additional insights, please visit the interactive Flume Household Water Use Index Dashboard.

About Flume
Inspired by California's record drought, Flume empowers homeowners to better understand their usage and conserve water. By providing real-time water use information, Flume protects the home, puts the power of water consumption and conservation in the customer's hands, and improves the relationship with our most precious resource. The Flume® Smart Water System consists of an easy-to-install sensor that adapts to most existing home water meters, which communicates water use to the homeowner in real-time. To date, Flume has tens of thousands of devices installed across the United States. Learn more at www.flumewater.com.

SOURCE Flume