Water flow regulations for showers in the United States are primarily set by the U.S. Department of Energy (DOE) and the Environmental Protection Agency (EPA) to conserve water and energy. These regulations limit the maximum flow rate of showerheads sold and installed in the country.
Here’s a breakdown of the key rules and standards:
1. Federal Showerhead Flow Standard
• Established: 1992 under the Energy Policy Act
• Maximum Flow Rate: 2.5 gallons per minute (gpm) at 80 psi (pounds per square inch) of water pressure
• Applies to all showerheads manufactured and sold in the U.S.
2. EPA WaterSense Standard (Voluntary)
• Launched: 2006
• Maximum Flow Rate: 2.0 gpm
• Must maintain good pressure and spray quality
• Showerheads that meet this standard carry the WaterSense label, meaning they are both efficient and effective
• Voluntary but widely adopted by states, municipalities, and building codes
3. State-Specific Regulations (Stricter in Some States)
Some states have gone further than the federal rule to encourage conservation:
California
• Current standard: 1.8 gpm
• Enacted during severe drought conditions and is now permanent
• Applies to showerheads sold or installed in the state
Washington
• Adopted 1.8 gpm standard, similar to California
New York
• Follows federal standard (2.5 gpm), but some city buildings (like in NYC) install low-flow heads for savings
Colorado, Hawaii, Vermont, and Oregon
• Also have adopted 2.0 gpm or 1.8 gpm max flow standards
4. Multi-Head Showers
• A 2010 federal clarification states that combined flow from all active heads in a multi-head system must not exceed 2.5 gpm unless each head is controlled separately.
5. Exemptions and Modifications
• Older homes may still have higher-flow heads unless updated
• Some commercial or institutional uses (like gyms or hotels) may have customized plumbing allowances but still must follow sale/manufacture restrictions
Why It Matters:
• Reducing flow from 2.5 to 2.0 gpm can save thousands of gallons of water per year
• Also reduces energy costs (less hot water used)
• EPA estimates households can save up to $70 per year just by switching to a WaterSense-certified showerhead
• the US allows a higher maximum flow than most other developed countries.
• Canada, Australia, and Singapore have stricter limits, often between 6–9 L/min.
• European countries generally don’t have mandatory flow restrictions yet, but eco-certifications (like BREEAM or LEED) push for more efficient fixtures.
• Water-scarce nations (e.g., South Africa, Israel, and parts of Australia) tend to enforce lower limits and strict conservation practices.
