Implementing Residential Toilet Retrofit Programs

The Northwest Water Planning Alliance (NWPA) Water Supply Sustainability Plan (WSSP) identifies residential retrofits as a priority conservation strategy. Because toilets are among the largest sources of indoor water use, replacing older models with more efficient versions can result in substantial savings. Several communities in Northeastern Illinois have launched toilet retrofit programs, and their experiences offer lessons for others considering similar efforts.

How toilet retrofits drive water savings
Federal plumbing standards adopted in 1992 reduced toilet water use to 1.6 gallons per flush (gpf), replacing older models that commonly used 3.5 to 5.0 gpf. Most retrofit programs now require U.S. Environmental Protection Agency’s (EPA) WaterSense-labeled models using 1.28 gpf or less, ensuring both efficiency and performance.
​
Because toilet upgrades permanently replace inefficient fixtures, the resulting savings persist over time. The NWPA WSSP estimates that if 50% of eligible residential households retrofitted their toilets, the NWPA region could save 2.8 million gallons of water per day (MGD), increasing to 5.5 MGD if all eligible residents participated. The question is, how can the NWPA achieve these estimated water savings?

 Lessons Learned from Regional Programs
The NWPA Technical Advisory Committee (TAC) has recently heard presentations on toilet retrofit programs from Rethink Water Joliet, Cook County Leak Repair, and Conserve Water for Kane. From these examples, we’ve learned the following lessons about successful toilet retrofit programs. 
Lesson 1: Anchor program design in education
Education is foundational for effective toilet retrofit programs. For some residents, understanding that every drop counts may be sufficient motivation to undertake a retrofit. For others, outlining the water savings benefits in more detail, including potential water bill savings, can incentivize a retrofit. For example, Conserve Water for Kane offers workshops for residents, a water-use calculator, and resources.
 
Lesson 2: Lower participation barriers
Successful toilet retrofit programs lower financial, technical, and administrative barriers. In addition to offering rebates for the toilet itself, covering installation costs can boost participation. Making requirements clear, outlining documentation needs, and communicating reimbursement timelines reduces frustration and increases completion rates. For example, the Cook County Leak Repair Program provides direct installation services and eliminates the need for upfront payment.
 
Lesson 3: Strengthen messaging
 Programs are most effective when messaging is clear, repeated, and delivered through trusted local channels such as utility communications, municipal websites, and community partners. Conserve Water for Kane leveraged University of Illinois Extension partnerships, while Joliet’s Rethink Water initiative integrates rebate information into ongoing conservation communications to reinforce visibility.
 
Lesson 4: Measure and Communicate Program Outcomes
Effective conservation programs are designed with measurable outcomes in mind. Tracking participation, fixture replacements, and estimated water savings helps communities assess whether rebate efforts are delivering meaningful demand reductions. Rethink Water Joliet has reported outreach and engagement metrics alongside program updates, while Conserve Water for Kane tracks applications submitted and toilets replaced. Communicating results builds public trust, supports continued investment, and allows programs to adapt and improve over time.
 
Conclusion: Advancing Conservation Through Residential Retrofit Programs
Residential toilet rebate programs offer a practical and measurable pathway to advance WSSP conservation goals. By targeting one of the largest components of indoor residential water use and aligning with verified efficiency standards, communities can generate durable, quantifiable savings. Regional experience suggests a clear path forward: reduce participation barriers, pair incentives with education, maintain consistent messaging, and track measurable outcomes. By building on regional experience and adapting proven approaches locally, communities can deliver measurable water savings.