PUC §781: (a) (1) Each water corporation with 500 or more service connections that is not subject to the requirements of Section 525, 526, 527, or 528 of the Water Code shall install, on and after January 1, 20

(a) (1) Each water corporation with 500 or more service connections that is not subject to the requirements of Section 525, 526, 527, or 528 of the Water Code shall install, on and after January 1, 2010, a water meter on each new service connection. (2) Each water corporation with 500 or more service connections as of January 1, 2010, that is not subject to the requirements of Section 526, 527, or 528 of the Water Code, shall install a water meter upon each unmetered service connection by January 1, 2025. (3) Each water corporation with less than 500 service connections as of January 1, 2010, that thereafter reaches 500 or more service connections and that is not subject to the requirements of Section 526, 527, or 528 of the Water Code, shall, within 10 years of attaining that threshold, install a water meter upon each unmetered service connection. (4) Each water corporation that is subject to the requirements of Section 525, 526, 527, or 528 of the Water Code shall install water meters pursuant to those sections. (b) (1) Each water corporation that has installed water meters, or caused water meters to be installed, that is not subject to Section 525, 526, 527, or 528 of the Water Code, shall, on and after January 1, 2015, charge customers for potable water based on the actual volume of deliveries, as measured by the water meter. This paragraph does not limit the authority of the commission to authorize a water corporation that promotes conservation through volumetric water pricing to determine and impose a rate, fee, or charge in addition to the charge for the actual volume of metered water delivered. (2) Each water corporation that is subject to Section 525, 526, 527, or 528 of the Water Code shall charge customers for potable water based on the actual volume of deliveries, as measured by the water meter, consistent with the requirements of those sections. (3) Notwithstanding paragraph (1), in order to provide customers with experience in volume-based water service charges, a water corporation that is subject to paragraph (1) may delay, for one annual seasonal cycle of water use, the use of meter-based charges for service connections that are being converted from nonvolume-based billing to volume-based billing. (c) A water corporation shall recover the cost of providing services related to the purchase, installation, operation, and maintenance of water meters in rates, fees, or charges. Rates, fees, or charges recovered by the water corporation pursuant to this section are subject to approval by the commission pursuant to Article 1 (commencing with Section 451) of Chapter 3 and Article 2 (commencing with Section 727) of this chapter. (d) The commission shall ensure that each water corporation that is subject to the requirements of this section or the requirements of the Water Measurement Law (Chapter 8 (commencing with Section 500) of Division 1 of the Water Code) comply with those requirements.