Conservation-Oriented Residential Rate Design Under New York Public Service Commission Regulation

The preceding chapters established that water conservation is an important public policy objective, that tiered residential water rates represent one of the principal tools used to encourage efficient water use, and that conservation policy distinguishes between essential household water use and discretionary demand. The next step is to examine how these principles have been incorporated into the regulatory framework governing New York's investor-owned water utilities.

The New York Public Service Commission is responsible for regulating investor-owned water utilities to ensure that rates are just and reasonable while providing safe, reliable, and adequate service. Through comprehensive rate proceedings, the Commission reviews utility revenues, infrastructure investment, customer service, conservation initiatives, and residential rate design before approving tariffs that govern how water service is billed.

Within this regulatory framework, conservation is not treated as a stand-alone initiative. Instead, it is incorporated into a broader package of utility programs intended to promote efficient water use while maintaining reliable public service. Residential rate structures, customer education, conservation outreach, leak reduction programs, rebates for water-efficient fixtures, and other demand-management measures are considered together as complementary elements of a comprehensive conservation strategy.

The Commission's recent proceedings involving Liberty Utilities (New York Water) Corp. and Veolia Water New York illustrate this integrated approach. Although the details of their approved tariffs differ, both utilities operate under Commission-approved residential rate structures that use inclining block pricing to encourage efficient water use. These pricing structures function alongside conservation programs designed to educate customers, improve water-use efficiency, and reduce unnecessary demand.

Importantly, the Commission's regulatory approach does not treat conservation-oriented rate structures as static. Instead, the operation of those rate structures remains subject to continuing evaluation when questions arise regarding how they function under actual customer conditions.

The Liberty Utilities rate proceeding provides one of the clearest examples. As part of the Commission-approved Joint Proposal, Liberty was required to conduct a detailed Threshold Analysis examining residential customers reaching Tier 4 during non-peak months. The purpose of the study was to determine whether residential customers whose usage appeared to consist primarily of indoor household demand were reaching the highest residential conservation tier. The Joint Proposal further provided that, if indoor household demand was found to reach Tier 4, additional study would be undertaken in consultation with Department of Public Service Staff to determine whether further evaluation or potential modifications were appropriate. This requirement demonstrates that the Commission expected the operation of conservation-oriented rate structures to be informed by evidence gathered under real-world conditions rather than by assumptions alone.¹⁸

The Veolia Water New York proceeding reflects the same broader conservation philosophy. In approving the Joint Proposal, the Commission continued conservation-oriented residential rate design together with customer education, water-efficiency programs, conservation outreach, and rebate initiatives. These complementary measures demonstrate that conservation pricing forms only one component of a broader regulatory strategy intended to encourage efficient water use while maintaining reliable utility service. As the Commission explained in approving the Joint Proposal, "The rate structure established in the Joint Proposal is conservation-oriented, with inclining rates designed to discourage discretionary usage, particularly in the summer."¹⁹ This statement reflects the Commission's own understanding of the purpose underlying the approved residential rate structure.

Taken together, these proceedings demonstrate several consistent characteristics of New York's regulatory approach. Conservation remains a continuing public policy objective. Residential rate design provides one mechanism for encouraging efficient water use. Conservation pricing operates alongside education, outreach, and efficiency programs rather than replacing them. Finally, the Commission's own proceedings demonstrate a willingness to evaluate how conservation-oriented rate structures perform under actual customer conditions when questions arise regarding their operation.

This regulatory framework naturally leads to the next question examined in this report. If conservation-oriented residential rate structures apply a common Tier 1 allocation to all residential customers, what does existing research tell us about the relationship between household occupancy and ordinary residential water demand? Understanding that relationship is essential before evaluating how conservation policies operate across households of different occupancy levels.