Every three years, Cal Water submits an Infrastructure Improvement Plan to an independent state agency and separate state watchdog, the Public Advocates Office, for review and approval. This process helps us continue providing a reliable supply of high-quality water for customers’ everyday needs and sufficient resources for firefighters.
2021 Infrastructure Improvement Plan
- 2021 IIP Application
- 2021 IIP Application Attachment A—Proposed Procedural Schedule
- 2021 IIP Application Attachment B—Financial Reports
- 2021 IIP Application Attachment C—Summary of Earnings
- 2021 IIP Application Attachment D—Proposed Customer Notices
- 2021 IIP Application Attachment E—Current Tariffs
- 2021 IIP Application Attachment F—Proposed Tariffs
2015 Infrastructure Improvement Plan
2012 Infrastructure Improvement Plan

Advice Letter
Advice letters are informal requests to the California Public Utilities Commission (CPUC) seeking approval or authorization.
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Infrastructure Improvement Plans
This page is designed to share helpful information on our 2024 Infrastructure Improvement Plan to continue to provide safe and clean drinking water.
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