10608.25.
(a) After December 31, 2020, an urban retail water supplier shall achieve a water efficiency target as provided for in this section.(b) Each urban retail water supplier shall develop a water efficiency target for 2025 in its 2020 urban water management plan required to be submitted by July 1, 2021, pursuant to Section 10621. An urban retail water supplier may determine the water efficiency target on a fiscal year or calendar year basis. An urban retail water supplier may adjust and update the water efficiency target, as appropriate, based upon population growth, changes in irrigable landscape acreage, and other changes that affect water use when the supplier reports its compliance in achieving the water efficiency targets and its
implementation of the identified performance measures in its 2025 urban water management plan required to be submitted by July 1, 2026, pursuant to Section 10621.
(c) An urban retail water supplier shall adopt one of the following methods for determining its water efficiency target pursuant to subdivision (b):
(1) Seventy-five percent of the urban retail water supplier’s base daily per capita water use calculated using the methodology developed by the department pursuant to Section 10608.20.
(2) (A) Establishment of a retail-level water efficiency target that is the sum of the following:
(i) The residential population multiplied by 55 gallons of water use per person per day.
(ii) For irrigable landscape served by a residential or dedicated irrigation meter, an estimate of total irrigation demands within the supplier’s service area, based on the following factors:
(I) Evapotranspiration adjustment factor of 1.0 for parcels developed before 1992 and for special landscape areas.
(II) Evapotranspiration adjustment factor of 0.8 for parcels developed between January 1, 1992, and December 31, 2009.
(III) Evapotranspiration adjustment factor of 0.7 for parcels developed between January 1, 2010, and December 31, 2015.
(IV) Evapotranspiration adjustment factor of 0.55 for residential parcels developed after January 1, 2016.
(V) evapotranspiration adjustment
factor of 0.45 for commercial parcels developed after January 1, 2016.
(VI) Parcels in commercial or noncommercial agricultural use may be included by the urban retail water supplier, at its sole discretion, using an evapotranspiration factor of 1.0 in the calculation of the water use efficiency target or in the calculation for compliance of the target.
(iii) A volume of water to account for the variances taken by the water supplier due to unique situations within the water supplier’s service area and developed pursuant to subdivision (f).
(B) An urban retail water supplier that adopts the method described in subparagraph (A) for determining its water efficiency target shall identify proposed performance measures, as appropriate, for efficient water use by its commercial, industrial, and institutional customers
consistent with the recommendations identified in the report required pursuant to subdivision (b) of Section 10608.45 in the water supplier’s 2020 urban water management plan.
(3) Ninety percent of the applicable hydrologic region target, as set forth in the state’s 20x2020 Water Conservation Plan, dated February 2010. If the service area of an urban retail water supplier includes more than one hydrologic region, the supplier shall apportion its service area to each region based on population or area.
(d) Each urban retail water supplier shall meet its adjusted 2025 water efficiency targets by December 31, 2025, unless the supplier reports to the department that economic or hydrologic conditions beyond the water supplier’s control rendered it impossible for the water supplier to do so. An urban retail water supplier may elect to determine and report progress toward achieving its
2025 water efficiency target on an individual or regional basis, as provided in subdivision (a) of Section 10608.28. An urban retail water supplier shall report on its compliance with this section in its 2025 urban water management plan required to be submitted by July 1, 2026, pursuant to Section 10621.
(e) An urban retail water supplier shall base its adjusted water efficiency target and compliance with that adjusted target on the best available information concerning population, irrigable landscape acreage, and other factors that affect water use within its service area. An urban retail water supplier shall calculate its compliance with subdivision (d) based on the method by which it set its water efficiency target, as follows:
(1) An urban retail water supplier with a water efficiency target determined pursuant to paragraph (1) of subdivision (c) shall calculate its compliance
with subdivision (d) by comparing the adjusted water efficiency target with the urban retail water supplier’s compliance daily per capita water use.
(2) An urban retail water supplier with a water efficiency target determined pursuant to paragraph (2) of subdivision (c) shall calculate its compliance with subdivision (d) by comparing the water efficiency target with the total volume of gross water use measured through residential and dedicated irrigation meters during the final year of the reporting period. The urban retail water supplier shall include in its report on compliance with subdivision (d) a report on the urban retail water supplier’s implementation of the performance measures for efficiency commercial, industrial, and institutional water use identified in its urban water management plan. If an urban retail water supplier includes parcels in agricultural use in its water efficiency target, the urban retail water supplier shall
include water use for those parcels in its compliance calculation.
(3) An urban retail water supplier with a water efficiency target determined pursuant to paragraph (3) of subdivision (c) shall calculate its compliance with subdivision (d) by comparing the adjusted water efficiency target with the urban retail water supplier’s compliance daily per capita water use.
(4) Water use or loss caused by conditions of disaster or extreme peril to the safety of persons and property, including, but not limited to, conditions, whether natural or human caused, of fire, flood, storm, drought, epidemic, riot, earthquake, or other condition, shall be excluded from the calculation of compliance with the water efficiency target.
(5) The deadline for an urban retail water supplier to submit its plan pursuant to subdivision (e) of
Section 10621 shall be extended if the department does not release the final database pursuant to Section 10608.47 on or before July 1, 2019. The extension shall equal the length of time between July 1, 2019 and the date of the department’s release of the final database.
(6) Each urban retail water supplier shall have the discretion to achieve its water efficiency target under this section and to design and utilize any rate structure in any manner consistent with that supplier’s legal authority.
(7) Each urban retail water supplier shall have the discretion to measure progress toward achieving its water efficiency target under this section by considering the factors described in subdivisions (d) to (f), inclusive, of Section 10608.24.
(8) Notwithstanding the method used by an urban retail water supplier to calculate
compliance with subdivision (c), each urban retail water supplier shall address water loss within its service area pursuant to Section 10608.34.
(f) The department, in consultation with the Urban Stakeholder Committee, shall develop all of the following and any other factors as may be identified by the committee:
(1) Standardized variance methodologies for all of the following:
(A) Livestock.
(B) Swamp coolers.
(C) Significant transient population increases.
(D) Construction water for soil compaction and dust control.
(E) Potable water use to supplement ponds
and lakes to sustain wildlife.
(F) Vegetation irrigated for fire protection.
(G) Landscapes irrigated with recycled water having high levels of total dissolved solids.
(H) Other water quality concerns.
(2) A methodology to calculate the irrigable area associated with special landscape areas by aerial imagery or date of parcel establishment so that an urban retail water supplier may develop appropriate water efficiency targets as described in paragraph (2) of subdivision (c).
(3) A process for the submission of supporting documentation for other variances that shall be included into the calculation of the urban retail water supplier’s water efficiency target as described in paragraph (2) of
subdivision (c).
(g) For purposes of this section, “special landscape area” means an area of the landscape dedicated solely to edible plants, recreational areas, areas irrigated with recycled water, or water features using recycled water designed within and having the same evapotranspiration adjustment factor as contained in the model water efficient landscape ordinance set forth in Chapter 2.7 (commencing with Section 490) of Division 2 of Title 23 of the California Code of Regulations, adopted on September 15, 2015.