Water Supply Reliability and Housing – Making it Work in Times of Drought

New Housing in Southern California is More Water Efficient and Conservative Than Ever Before

Inside and outside the home, water-efficient and conservative practices are on display. Super-efficient fixtures and appliances are teamed with low to zero water-use landscapes, designed to be California climate-friendly year around.

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Water Efficiency of New Housing is Backed Up by Water Agency Planning and Monitoring Programs and Independent Expert Reports and Studies:

1. Urban housing water demand and growth is embedded in Integrated Regional Water Management Plans prepared by water suppliers and distributors throughout Building Industry Association of Southern California’s (BIASC) region--by and large, the Metropolitan Water District of Southern California’s service area. Plans are forward-looking, decades into the future.
   

2. BIASC home builders are setting the pace for making conservation a way of life by using a new indoor water use efficiency standard in California, as described in 2018 with SB 606 (Hertzberg) and AB 1668 (Friedman). Housing planned for and approved after 2023 uses new per capita demand standards that are among the strictest in the nation.
   

3. State of California 2021 Results of the Indoor Residential Water Use Study (IRWUS) reports California residential properties are already using less than 50 gallons of water per day, with one-quarter of properties currently using less than 45 gallons per day.
   

4. 2021 IRWUS sets aggressive timelines for lowering indoor water use efficiency standards for residential properties, from 55 gallons per capita daily currently to 42 by 2030.
   

5. 2021 IRWUS also predicts future declines in residential water use, attributed to more efficient appliances and fixtures in new homes.
   

6. Expert studies report a 22% decline in in-home water use between 1999 and 2016, attributable to efficiency gains inside the home.

   • Water Research Foundation - Residential End Uses of Water, Version 2, Executive Report 2016

   • Analysis of Water Use in New Single-Family Homes, 2011

   • California Single Family Water Use Efficiency Study, 2011
     

7. Public Policy Institute of California (PPIC) in 2016 found that per capita urban water use fell sharply during the 2011-2016 drought, even with an increasing population. Much of the water savings were a result of decreased outdoor use.

   • PPIC Water for Cities, October 2016

   • Just the Facts, Water Use in California, May 2019
     

8. Dramatic declines in total residential (typical three-bedroom home) water use have been observed over the past 50 years:

   • California Home Building Foundation: 2010 Water Use in the California Residential Home

   • Analysis of Water Use in New Single-Family Homes, 2011

   • Water Research Foundation - Residential End Uses of Water, Version 2 Executive Report

   • State of California 2021 Results of the Indoor Residential Water Use Study (IRWUS)

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Overview of BIASC Water Supply and Reliability Policy Positions

• BIASC supports the construction of a new Delta conveyance facility, funded completely by State Water Contractors

• BIASC supports increasing water storage statewide in the form of new and expanded existing reservoirs and the recharge of groundwater basins

• BIASC supports water conservation when it’s cost-effective for consumers

• BIASC supports outdoor water use efficiency efforts in landscape irrigation, such as smart controllers, low to zero water use landscape areas, and greater use of recycled water where feasible