Staff at the Regional Water Quality Control Board, Colorado River Basin (Regional Board) received and reviewed the draft CV-SNMP Development Workplan dated April 30, 2021. The Coachella Valley Water District (representing the CV-SNMP Agencies) received a letter from the Regional Board dated June 30, 2021 with comments and suggested revisions to the draft CV-SNMP Development Workplan. The Regional Board comment letter is attached to this Appendix C.
The CV-SNMP Agencies prepared responses to the Regional Board comments and revised the CV-SNMP Development Workplan to address the comments. The Regional Board’s comments and the CV-SNMP Agencies’ responses are described below.
Item Location Regional Board Comment Response from CV-SNMP Agencies 1 Section
1.0
of the CV-SNMP is to sustainably manage salt
and nutrient loading in the Coachella Valley
Groundwater Basin in a manner that protects
its beneficial uses.
Sustainability focuses on meeting the needs
of the present without compromising the
ability of future generations to meet their
needs. The Sustainable Groundwater
Management Act (SGMA) considers
sustainable groundwater management to be
occurring within a basin that is operated in
such a way so as not to cause “undesirable
results,” such as chronic depletion of
groundwater, groundwater degradation, or
land subsidence.
The Regional Water Board recommends the
TAC develop a plan to manage identified salt
and nutrient loading sources and provide a
definition of what beneficial use protection
will consist of, integrating the
antidegradation analysis into the
stakeholder’s definition of protected.
The CV-SNMP Agencies, which include
Groundwater Sustainability Agencies in the
Indio and Mission Creek Subbasins,
understand the SGMA definitions and
requirements for sustainable groundwater
management. SGMA compliance work for
the two medium-priority basins in the
Coachella Valley is being conducted under
separate efforts and will leverage the
development and implementation of the CV-
SNMP for the sustainable management of
salts and nutrients.
The CV-SNMP Agencies believe the CV-SNMP
Development Workplan addresses the
Regional Board’s recommendation to
develop an SNMP that will manage identified
salt and nutrient loading (see Section 4.3 of
the Workplan) to protect defined beneficial
uses (Section 4.5), and will include an anti-
degradation analysis that satisfies the
requirements of State Board Resolution 68-
16 (Section 4.10).
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 2 Section
1.3
Agencies have concluded that numeric
objectives for [total dissolved solids] TDS and
nitrate in groundwater are necessary to
resolve the concerns of the Regional Board.
Identifying a water quality objective is
necessary to determine the assimilative
capacity of the aquifer. To assess the
assimilative capacity of salts, the 2015 CV
SNMP cited the “upper limit” Secondary
Maximum Contaminant Level (SMCL) of
1,000 milligrams per liter (mg/I) as the water
quality objective for total dissolved solids
(TDS) excluding the more protective and
“recommended limit” SMCL of 500 mg/I. The
water quality data indicated that many areas
within the basin had TDS concentrations that
were less than 500 mg/I (the lower
“recommended limit” of the SMCL range).
Resolution No. 68-16, Statement of Policy
with Respect to Maintaining High Quality
Waters in California (Antidegradation Policy)
states “Whereas the quality of some waters
of the State is higher than that established
by the adopted policies and it is the intent
and purpose of this Board that such higher
quality shall be maintained to the maximum
extent possible consistent with the
declaration of the Legislature; ...”
The Regional Water Board recommends that
the SNMP provide the scientific basis
including an antidegradation analysis for any
proposed water quality objectives.
The CV-SNMP Agencies believe that the
approach presented in the CV-SNMP
Development Workplan addresses the
Regional Board’s recommendation to
provide the scientific basis for setting water
quality objectives pursuant to CWC Section
13241 and will include an anti-degradation
analysis that satisfies the requirements of
State Board Resolution 68-16 (see Section
4.10 of the Workplan).
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 3 Section
1.3.1
Development Workplan must address each of
these factors in setting the TDS objectives for
groundwater management zones.
California Water Code § 13241 [Water
quality objectives] states that “Each regional
board shall establish water quality objectives
in water quality control plans as in its
judgment will ensure the reasonable
protection of beneficial uses and the
prevention of nuisance;...” The CV SNMP
stakeholders may present recommendations
regarding TDS water quality objectives,
which the Regional Water Board will review
and make a final determination regarding
adoption into the Water Quality Control Plan
for the Colorado River Basin Region (Basin
Plan).
The Regional Water Board recommends
deleting the word ‘setting’ and using the
word ‘recommending’ TDS objectives for
groundwater.
The CV SNMP Development Workplan has
been revised to replace the word “setting”
with the word “recommending.”
4 Section
2.2.2
general occurrence of groundwater, and how
groundwater flows through and discharges
from each subbasin.
Publicly available data on the San Jacinto
Tunnel installed through fractured bedrock
in the 1930’s and operated by Metropolitan
Water District (MWD) reports that the
fractured crystalline bedrock units contain
and convey a substantial amount of water in
the subsurface. The concept of a “mega-
watershed groundwater system” from
mountain block recharge is provided in the
works of Robert Bisson and Jay Lehr.1
In that mountain front recharge is identified
later in the CV SNMP, Regional Water Board
suggests the inclusion of a discussion on the
water bearing nature of the surrounding
fractured bedrock units.
Section 2.1 has been updated to recognize
that the bedrock formations in the hills and
mountains that surround the groundwater
basin can contain groundwater within pore
spaces and fractures.
Subsurface inflow from the bedrock
formations will be included in the technical
analysis of salt and nutrient loading (Sections
4.3, 4.7, and 4.8 of the Workplan).
1 https://www.oregondigital.org/downloads/oregondigital:df710j60x
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 5 Section
2.3.2
salts and nutrients are discharged from each
subbasin.
Dr. John Wilson’s (New Mexico Tech) work
provides strong research in regard to the
removal of salts and nutrients through
microbial activity. Specifically, see Dr.
Wilson’s study of salt and nutrient uptake
and removal where there is mixing of
shallow groundwater and surface water
(hyporheic zone). 2
The Regional Water Board recommends
evaluating microbial uptake as a salt and
nutrient management mechanism.
Section 2.3.1 has been revised to include
“microbial processes” in the description of
the complexities of the N/TDS loading
process.
6 Section
4.2
objective of this task is to convene a CV-
SNMP Stakeholder Group and the CV-SNMP
Technical Advisory Committee (TAC). The CV-
SNMP Agencies and the selected consultants
will organize and run both groups during the
implementation of the CV-SNMP
Development Workplan.
A locally driven and controlled, collaborative
process open to all stakeholders and the
regional water board will contribute to the
development of a CV SNMP that will manage
salts and nutrients on a basin-wide basis and
achieve the goals of groundwater
sustainability, recycled water use, and water
quality protection.
The Regional Water Board recommends
deleting the word “run” and adding a
different word or words such as “will
facilitate.”
Section 4.2 has been revised to replace the
word “run” with “facilitate.”
2 https://www.sciencedirect.com/topics/earth-and-planetary-sciences/hyporheic-zone
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 7 Section
4.2.1
stakeholders include but are not limited to:
the agricultural community and groups; golf
course industry groups; tribes; the Coachella
Valley Regional Water Management Group;
the Groundwater Sustainability Agencies in
the Coachella Valley; all major water and
wastewater agencies; industrial dischargers;
county and city land use planning agencies;
Federal and State agencies; and
nongovernmental organizations (NGOs).
A critical first step will be to solicit input from
the CV-SNMP Stakeholder Group as to their
issues, needs and wants. This information
will be collected up front so the CV-SNMP
Agencies and consultants can proactively
address stakeholder concerns, and
potentially incorporate them in the CV-SNMP
development process.
Achieving the goals of groundwater
sustainability, recycled water use, and water
quality protection is best achieved through
the management of salts and nutrients on a
basinwide basis through collaborative
processes open to all stakeholders.
Documenting and addressing the input from
an all-inclusive stakeholder group will help
identify the water use needs of a diverse
population and address historical and state-
wide SNMP development challenges
identified during the 2018 Policy revision
such as managing salt and nutrient loading to
the basin from sources other than recycled
water and the ability/authority of the
stakeholders to implement best
management practices and salt and nutrient
management measures.
The Regional Water Board encourages the
CV SNMP Agencies to keep all-inclusiveness
as a priority and involve all major
stakeholders within the basin. The CV SNMP
Agencies should also consider the inclusion
of significant stakeholders from outside the
basin such as The Colorado River Basin
Salinity Control Program and the MWD.
Section 4.2.1 has been revised to:
- Add the Colorado River Basin Salinity
Control Forum and the Metropolitan
Water District of Southern California to
the list of potential CV-SNMP
stakeholders.
- Include the following bullet to describe
the objectives of convening the CV-SNMP
Stakeholder Group:
Understand the ability/authority of
the stakeholders to implement best
management practices and salt and
nutrient management measures.
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 8 Section
4.2.2
Board staff will be encouraged to participate
on the TAC in an advisory role.
Regional Water Board understands that
critical details and decisions to develop an
adequate CV SNMP will be established
through the TAC and are committed to
working with this committee.
Comment noted and appreciated.
9 Section
4.3
objective of this task is to quantify the
individual components of N/TDS (nitrate and
TDS) loading to groundwater.
Mountain front recharge has been identified
as a potential source of aquifer recharge
originating from within the basin’s
watershed.
The Regional Water Board recommends
quantifying the salt and nutrient loading
from the mountain front recharge
component through evaluation of
representative bedrock springs as indicators
of the hydrologic conditions of the fractured
bedrock units.
Section 4.3.1 has been revised to include the
collection of historical “Water-quality data
from bedrock springs, wells, and streamflow
within the watersheds tributary to the
Coachella Valley” to characterize the water
quality of subsurface inflow from the
surrounding mountains and hills.
10 Section
4.3
characterization of N/TDS loading will be
performed for a recent historical period to
the present to characterize seasonal
variations and long-term trends in loading
and generate estimates of N/TDS loads in the
vadose zone. The length of the historical
period will be defined as part of this task but
should be long enough to characterize the
N/TDS loads in the vadose zone.
The required antidegradation analysis
component of the CV SNMP, discussed in
Section 4.10.3 of the Workplan, will need to
incorporate a discussion on the impacts of
elevated salinity to the public and the public
infrastructure since 1968.
The Regional Water Board recommends
evaluation of past nitrate and salt (TDS)
loading estimates for each management
zone extending at least to 1968.
Comment noted. The SNMP Agencies will
conduct the required antidegradation
analysis in accordance with the requirements
of the Antidegradation Policy. The exact
length of the “historical period” will be
defined as part of this task. Considerations
will include the requirements of the
Antidegradation Policy, as well as the
availability of data and information and
solute travel times through the vadose zone.
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 11 Section
4.3.2
methods are finalized, the time-history of the
volumes and associated N/TDS
concentrations will be estimated and
described for each N/TDS loading term.
The CV SNMP must identify what ‘methods’
the Workplan is referring to.
Refer to the preceding paragraph.
The “methods” are the “the types of tables,
maps, and data graphics that can be
prepared with the available data to
characterize historical and current N/TDS
loading to groundwater.”
The text in 4.3.2 has been revised to replace
the word “methods” with “types of tables,
maps, and data graphics.”
12 Section
4.4 The introduction to Section 4.4 states: The
objective of this task is to characterize nitrate
and TDS concentrations in groundwater as of
2020 (i.e. current conditions). The
characterization will include an analysis of
the time history of nitrate and TDS
concentrations in groundwater that led to
current conditions.
The Regional Water Board concurs that
establishing existing water quality is
necessary to compute the potential
existence and magnitude of assimilative
capacity for a basin, subbasin, or
management zone and supports other
proposed Workplan tasks; and also agree
that the proposed evaluation of past water
quality will assist with an understanding of
nitrate and TDS historical trends in
groundwater.
The Regional Water Board expects the fully
developed groundwater monitoring plan to
provide groundwater quality data that is
representative of the management zones
and encourages the TAC to develop a
technically defensible method to evaluate
the ambient water quality of each area.
The CV-SNMP Agencies completed the CV-
SNMP Groundwater Monitoring Program
Workplan (final report dated December 23,
2020), and the Regional Board approved the
CV-SNMP Groundwater Monitoring Program
Workplan in a letter dated February 21,
2021. The intent of the monitoring program
is to provide groundwater data that is
representative of all subbasins, subareas,
and depth-specific aquifer systems within
the Basin. The approved CV-SNMP
Groundwater Monitoring Program Workplan
is included as Appendix A and is summarized
in Sections 2 and 3 of this workplan.
Section 4.5 describes the process to define
the ambient water quality (AWQ) metric in
each management zone that will be used to
estimate ambient water quality conditions
and assess beneficial use protection. An
AWQ metric is a technical method to
estimate “ambient” N/TDS concentrations in
each groundwater management zone. The
purpose of AWQ metrics is to enable the
comparison of ambient N/TDS
concentrations in groundwater versus the
beneficial-use thresholds and water quality
objectives, and thereby indicate the state of
beneficial use protection.
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 13 Section
4.5
of this task will provide the necessary
information to:
- Support subsequent tasks in this
workplan to:
Set TDS objectives pursuant to CWC
13241(a): Past, present, and
probable future beneficial uses of
water
As previously stated, per California Water
Code § 13241 water quality objectives are
established by the regional boards. It is
appropriate for the CV SNMP stakeholders to
recommend TDS water quality objectives,
which the Regional Water Board will review
and make a final determination regarding
adoption into the Basin Plan.
The Regional Water Board recommends
deleting the word ‘Set’ TDS objectives and
using the word ‘Recommend’ TDS objectives.
The CV SNMP Development Workplan has
been revised to replace the word “Set” with
the word “Recommend.”
14 Section
4.5.1 Hydrologically vulnerable areas, as identified
in the Groundwater Ambient Monitoring
Assessment (GAMA) Groundwater
Information System database, exist where
soil or rock conditions are more vulnerable
(or susceptible) to groundwater
contamination, and where aggressive salt
and nutrient management practices may be
warranted.
The Regional Water Board recommends
including hydrologically vulnerable areas as
one of the criteria to assist with delineation
of management zones.
The CV SNMP Development Workplan has
been revised to add “Location of
hydrologically vulnerable areas as identified
in the GAMA Groundwater Information
System database” as one of the criteria to
assist with delineation of management
zones.
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 15 Section
4.5.3
ambient nitrate and TDS concentrations will
be compared to the beneficial-use thresholds
to assess the current state of beneficial use
protection.
Assimilative capacity is not synonymous with
the amount of allowable degradation. The
Regional Water Board recommends that the
CV SNMP not only provide the technical basis
for determining the degree of water quality
degradation allowable, but to also identify
the potential impacts/injury to the members
of the public. The SNMP should identify costs
associated with using water with elevated
nitrates and TDS levels and if there are
potential impacts to human health, safety, or
the environment with the proposed changes
to water quality [and assimilative capacity]
over time.
Section 4.10 of the CV SNMP Development
Workplan addresses the Regional Board
recommendation in this comment.
The numeric TDS objectives proposed in the
CV-SNMP will be derived through a
documented technical analysis described in
the Workplan. The TDS objectives can be
used by the Regional Board to determine the
degree of water quality degradation
allowable (if any). Section 4.10.2 describes
that a written demonstration will be
prepared, referencing all technical work
performed in prior tasks, to illustrate how
the CV-SNMP and its recommended TDS
objectives collectively satisfy the
requirements of CWC 13241, including the
protection of beneficial uses.
Section 4.10.3 describes that an
antidegradation demonstration will be
prepared to illustrate how the CV-SNMP and
its recommended TDS objectives collectively
satisfy the requirements of State Board
Resolution 68-16 (the Antidegradation
Policy), again including the protection of
beneficial uses. The antidegradation
demonstration also will include a socio-
economic evaluation of, but not limited to:
- The melded unit cost of the total water
supply under the CV-SNMP.
- The funding mechanisms available to the
agencies responsible for CV-SNMP
implementation and the cost impacts to
those agencies and their rate payers.
- The potential costs associated with using
groundwater if the CV-SNMP projects
higher N/TDS concentrations in the
future.
The antidegradation demonstration also will
include the rationale for determining that
the CV-SNMP is or is not justified by the
socio-economic considerations.
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 16 Section
4.5.3
MODFLOW output files need to be assessed
to determine whether they meet the
requirements of the water-quality modeling
and its cascading modeling approach.
The Regional Water Board recommends
calibrating the model to demonstrate the
model’s ability to return reasonable results
for historical measured conditions.
The two MODFLOW models are calibrated
and are currently being updated and used to
support SGMA compliance in the Mission
Creek subbasin and the Indio subbasin.
17 Section
4.6.2
processes may be important to timing and
magnitude of N/TDS loading to the saturated
zone, particularly for return flows from the
land surface through partially saturated
sediments.
The Regional Water Board recommends the
consideration of previously mentioned
hyporheic zone research, which has
demonstrated that the potential for salt and
nutrient removal via vadose zone processes
is measurable.
Section 4.6.2 has been revised to include
“microbial processes in the hyporheic zone”
as criteria to consider in developing
modeling procedures for simulating the
vadose zone.
18 Section
4.6.5
River water is a major source of
supplemental water that supports
groundwater basin sustainability and the
economy of the Coachella Valley. The future
N/TDS concentrations of Colorado River
water will affect the quality of groundwater.
The Regional Water Board recommends that
the CV SNMP include an evaluation of
climate change on the availability and quality
of the Colorado River water source. If the
evaluation indicates that the Colorado River
water quality will be negatively impacted,
potentially degrading the quality of the
Coachella Valley groundwater, mitigation
measures must be identified and evaluated
for potential implementation.
Climate change could potentially impact the
quality of Colorado River Water. The
following phrase has been added to Section
4.6.5 to describe what the Technical
Consultant should review before
recommending assumptions for N/TDS
concentrations of Colorado River water for
water-quality modeling over the planning
period: ”review available information on
salinity projections for Colorado River water
including any predicted impacts from climate
change.”
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 19 Section
4.6.6
quality models will not be calibrated using
traditional methods of model calibration to
historical data targets.
The Regional Water Board recommends the
SNMP include proxy tests for the calibration
of the model to historically verifiable
datasets.
The CV-SNMP Agencies agree that the water-
quality models should be capable of
simulating historically verifiable datasets.
The introduction of Section 4.6 has been
modified to state that the water-quality
models should have “the ability to
reasonably simulate groundwater-quality
conditions over a historical period” and a
new subsection has been added to the
Workplan: Section 4.6.6 Develop Procedures
for Verifying the N/TDS Forecasting Tools.
20 Section
4.7.1 The objective of this section is to develop a
‘baseline’ planning scenario that represents
the current water supply plans and water
management plans for the Coachella Valley.
The baseline scenario must provide a
discussion of the water quality of both
imported (allochthonous) water and sources
of groundwater replenishment originating in
the basin (autochthonous). Also include a
reasonable economic forecast of the direct
effects associated with the projected
nutrient and salt loading in the baseline
scenario. A similar economic evaluation was
conducted in the Central Valley Region.3
The CV-SNMP Development Workplan lays
out a strategy to perform a holistic
evaluation of all sources of salt and nutrient
loading for the Baseline Scenario (as well as
all CV-SNMP Scenarios).
The economic analysis for the Baseline
Scenario (and the CV-SNMP Scenarios) is
described in Section 4.9. The text in Section
4.9.1 has been revised to include the
potential need to analyze the costs
associated with the effects of potential
future increases in groundwater salinity.
3 https://www.waterboards.ca.gov/rwqcb5/water_issues/salinity/library_reports_programs/econ_rpt_final.pdf
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 21 Section
4.7.2
simulation results of the Baseline Scenario
will be evaluated to determine if CV-SNMP
implementation measures are potentially
necessary in the future to control N/TDS
loading to protect the beneficial uses of
groundwater in specific management zones.
Section 6.2.4.4 of the Policy states that a
required component of the SNMP is
“Implementation measures to manage or
reduce the salt and nutrient loading in the
basin on a sustainable basis and the intended
outcome of each measure.” Additionally, the
Department of Water Resources (DWR)
notified many of the CV SNMP Agencies
through their affiliation as a Coachella Valley
Groundwater Sustainability Agency (GSA)
that their Groundwater Sustainability Plan
(GSP) developed pursuant to the SGMA
should continue investigations into ways to
reduce water quality impacts associated with
importing Colorado River water. The DWR
recommended that the GSAs take aggressive
steps to further quantify the nature and
scope of water quality issues associated with
importing water (allochthonous supply) into
the Subbasin, establish reasonable and
achievable standards, and begin to adopt
and implement projects and management
actions that will achieve sustainability with
regard to groundwater quality, and to do so
on an accelerated basis.
The CV SNMP must identify and evaluate
implementation measures that have the
potential to control salt and nutrient loading
and protect groundwater in the Coachella
Valley on a sustainable basis.
The CV-SNMP Agencies believe that the CV-
SNMP Development Workplan fully
addresses the Regional Board’s comment.
The workplan lays out a strategy to perform
a holistic evaluation of all sources of salt and
nutrient loading, the expected future
changes in groundwater quality, and any
predicted impairment of beneficial uses of
groundwater. Equipped with this
information, the CV-SNMP Agencies will then
explore and evaluate the effectiveness and
costs of CV-SNMP implementation measures
(i.e. projects and/or programs) to manage
N/TDS loading, and then recommend a
preferred CV-SNMP approach to the
Regional Board that will protect beneficial
uses of groundwater on a sustainable basis.
This work will be performed in an open,
transparent process through the TAC and CV-
SNMP Stakeholder groups with Regional
Board participation and input throughout.
22 Section
4.8 Pages 54 and 55 of the Workplan states: Task
4.8 is necessary if Task 4.7 concludes that CV-
SNMP implementation measures are
potentially necessary in the future to protect
the beneficial uses of groundwater in
management zones. If not, then Tasks 4.8
and 4.9 in this workplan are not necessary to
execute.
The objective of Task 4.8 is to develop CV-
SNMP implementation measures that have
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies the potential to control N/TDS loading and
protect beneficial uses of groundwater in the
Coachella Valley on a sustainable basis.
Section 4.8 of the Workplan is an essential
component of the CV SNMP, and without it
the impact of the SNMP is reduced to a
groundwater monitoring plan. Including
implementation measures in the CV SNMP is
important as the SNMP has been identified
as part of the groundwater management
strategy for the Coachella Valley and is
referenced in water management plans
generated by the Coachella Valley Integrated
Regional Water Management Planning
(IRWMP) Group, the Urban Water
Management Planning (UWMP) Group, and
the GSAs. As previously stated, DWR’s
approval of the Coachella Valley GSP
recommended implementing salt and
nutrient management projects and actions
that will achieve sustainability with regard to
groundwater quality, and to do so on an
accelerated basis.
A major source of salt (TDS) entering the
Coachella Valley groundwater resources is
from groundwater augmentation using water
imported into the basin from another
location (allochthonous), i.e. the Colorado
River. The CV SNMP must identify and
evaluate management strategies that
improve and enhance the allochthonous
sources of groundwater augmentation and
include how impacts to groundwater quality
from imported supplies can be offset
(mitigated) by replenishing the groundwater
resource with higher quality water from
sources originating in the basin
(autochthonous), as demonstrated in
other regions of the state,4 as well as other
strategies. The Regional Water Board
recommends the CV SNMP propose
management scenarios for consideration
including descriptions of how
implementation/mitigation measures will be
specifically developed to manage or reduce
See response for Item 20 above.
The CV-SNMP Agencies contend that it is
premature to develop specific
implementation measures at the “workplan
stage” in the development of the CV-SNMP
update. The CV-SNMP Development
Workplan proposes to develop and evaluate
implementation measures at the appropriate
time: after the evaluation of historical and
current groundwater quality; after the
evaluation of all sources of N/TDS loading;
after the delineation of management zones
and the description of their beneficial uses;
and after the evaluation of future N/TDS
concentrations in management zones under
the Baseline Scenario. Only then are the CV-
SNMP Agencies, the Regional Board, and
other CV-SNMP stakeholders in a
knowledgeable position to recommend the
appropriate location, type, and timing of
implementation measures that will
effectively and efficiently manage N/TDS
concentration in groundwater to protect
beneficial uses on a sustainable basis.
4 https://www.usbr.gov/lc/socal/reports/LASGwtraugmentation/AppC.pdf
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies the salt and nutrient loading in the basin on
a sustainable basis and the intended
outcome of each measure.
23 Section
4.8.2
the recommended CV-SNMP Scenarios will be
implemented in the models, the model
simulations will be conducted, and the model
results will be evaluated and compared
against the Baseline Scenario for their
effectiveness in controlling N/TDS loading
and protecting beneficial uses.
If the groundwater model is not calibrated to
historically verifiable accuracy, the use as a
comparative tool may be subjective. The
Regional Water Board recommends the
SNMP include proxy tests for the calibration
of the model to historically verifiable
datasets.
A new subtask has been added to Task 4.6:
4.6.6 Develop Procedures for Verifying the
N/TDS Forecasting Tools.
Task 4.7 has been revised to state that these
procedures will be implemented during the
construction of the water-quality models to
demonstrate their ability to reasonably
simulate historical groundwater-quality
conditions.
24 Section
4.10
objective of this task is to select a preferred
CV-SNMP Scenario, which will form the basis
for a CV-SNMP implementation plan and any
required updates to the Basin Plan.
The Regional Water Board recommends
deleting the word “required”’ and using the
word “recommended” in reference to
updates to the Basin Plan.
The CV SNMP Development Workplan has
been revised to replace the word “required”
with the word “recommended.”
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 25 Section
4.10.2
Water Code (CWC) section 13241 lists the
factors to consider when establishing water
quality objectives without unreasonably
affecting beneficial uses.
The Regional Water Board recommends that
the economic evaluation include impacts
related to elevated salinity in groundwater
and consider the correlated impacts to the
assigned beneficial use. The SNMP should
also identify human health, safety, and
environmental impacts associated with the
potential adoption of TDS water quality
objectives. It is the responsibility of the
involved stakeholders developing the CV
SNMP to solicit public input and approval.
The SNMP-Agencies agree that the CV-SNMP
must include evidence and analysis to
support findings required by California Water
Code section 13241 and State Water Board
Resolution No. 68-16, Statement of Policy
with Respect to Maintaining High Quality of
Waters in California (Antidegradation Policy).
In accordance with California Water Code
section 13241, to establish water quality
objectives in a water quality control plan, the
Regional Board must consider certain factors
related to the proposed water quality
objectives, including “economic conditions”
and the “need for developing housing within
the region.” Because the CV-SNMP may be
used by the Regional Board to establish
water quality objectives, the CV-SNMP will
include sufficient evidence and analysis of all
aspects of the “economic conditions,” the
“need for developing housing within the
region” and the other factors in Section
13241 as they relate to the issues addressed
in the CV-SNMP. In addition, in accordance
with the Antidegradation Policy and Section
6.2.4.5 of the 2018 Water Quality Control
Policy for Recycled Water, the CV-SNMP will
include evidence and analysis demonstrating
consistency with the Antidegradation Policy,
including, but not limited to, evidence and
analysis related to the “maximum benefit” to
the people of the state related to the issues
addressed in the CV-SNMP.
The economic analysis for the Baseline
Scenario (and the CV-SNMP Scenarios) is
described in Section 4.9. The text in Section
4.9.1 has been revised to include the
potential need to analyze the costs
associated with the effects of potential
future increases in groundwater salinity.
Appendix C: Responses to Comments on the Draft CV-SNMP Development Workplan
Item Location Regional Board Comment Response from CV-SNMP Agencies 26 Section
4.10.3
antidegradation demonstration will be
prepared as required by Section 6.2.4.5 of the
2018 Policy. The objective will be to illustrate
how the preferred CV-SNMP Scenario and
N/TDS objectives collectively satisfy the
requirements of State Board Resolution 68-
16 (the Antidegradation Policy).
Section 6.2.4.5 of the Policy states that one
of the required components of the SNMP
includes an antidegradation analysis. The
antidegradation analysis must consider all
past (since 1968), current, and future salt
and nutrient loading that is anticipated to
occur under the preferred CV SNMP
Scenario, and how this has and will continue
to affect groundwater quality. The analysis
should consider the changes in population
and land use practices and their impacts to
groundwater quality. The results of the
antidegradation analysis will potentially
identify hydrologically sensitive areas and
direct the CV SNMP Agencies to evaluate the
need for and the degree of management or
mitigation and regulatory oversight that will
be required to protect water quality.
The CV-SNMP Development Workplan
includes an anti-degradation analysis that
will satisfy the requirements of State Board
Resolution 68-16 (Section 4.10) and will
address the Regional Board
recommendations in this comment.
This page intentionally left blank.
APPENDIX 4-A
GROUNDWATER LEVEL MONITORING WELL HYDROGRAPHS
This page intentionally left blank.
Appendix A-1
Groundwater Elevation
Hydrograph
03S03E08A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
1,150
1,200
1,250
1,300
1,350
1,400
1,450
1,500
1,550
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
03S03E08A01S
Appendix A-2
Groundwater Elevation
Hydrographs
03S04E17K01S and
03S04E22A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
550
600
650
700
750
800
850
900
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
03S04E17K01S | 03S04E22A01S
Appendix A-3
Groundwater Elevation
Hydrographs
03S04E14J01S and
03S05E30G01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
400
450
500
550
600
650
700
750
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
03S04E14J01S | 03S05E30G01S
Appendix A-4
Groundwater Elevation
Hydrographs
04S05E08R01S and
04S05E05K01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
100
150
200
250
300
350
400
450
500
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
04S05E08R01S | 04S05E05K01S
Appendix A-5
Groundwater Elevation
Hydrographs
04S05E15C01S and
04S06E18Q04S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
0 50
100
150
200
250
300
350
400
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
04S05E15C01S | 04S06E18Q04S
Appendix A-6
Groundwater Elevation
Hydrographs
03S04E20F01S and
03S04E30C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
450
500
550
600
650
700
750
800
850
900
950
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
03S04E20F01S | 03S04E30C01S
Appendix A-7
Groundwater Elevation
Hydrograph
04S06E18Q04S
Appendix A-7
Groundwater Elevation
Hydrographs
04S06E20M02S and
04S06E28H02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-100
-50
0 50
100
150
200
250
300
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
04S06E20M02S | 04S06E28H02S
Appendix A-8
Groundwater Elevation
Hydrographs
03S04E35R01S and
03S04E34R01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
250
300
350
400
450
500
550
600
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
03S04E34R01S | 03S04E35R01S
Appendix A-9
Groundwater Elevation
Hydrographs
05S06E10L01S and
05S06E05Q01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-100
-50
0 50
100
150
200
250
300
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S06E10L01S | 05S06E05Q01S
Appendix A-10
Groundwater Elevation
Hydrographs
04S04E24E01S and
04S04E13C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
100
150
200
250
300
350
400
450
500
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
04S04E24E01S | 04S04E13C01S
Appendix A-11
Groundwater Elevation
Hydrographs
05S07E09D01S and
05S07E04A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 50
100
150
200
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S07E09D01S | 05S07E04A01S
Appendix A-12
Groundwater Elevation
Hydrographs
04S04E24H01S and
04S05E29A02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
0 50
100
150
200
250
300
350
400
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
04S04E24H01S | 04S05E29A02S
Appendix A-13
Groundwater Elevation
Hydrographs
04S05E27E01S and
04S05E22C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
0 50
100
150
200
250
300
350
400
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
04S05E27E01S | 04S05E22C01S
Appendix A-14
Groundwater Elevation
Hydrographs
04S05E36M01S and
05S06E06B03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-50
0 50
100
150
200
250
300
350
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
04S05E36M01S | 05S06E06B03S
Appendix A-15
Groundwater Elevation
Hydrographs
05S06E20A02S and
05S06E13D01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-100
-50
0 50
100
150
200
250
300
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S06E20A02S | 05S06E13D01S
Appendix A-16
Groundwater Elevation
Hydrographs
05S07E32H01S and
05S07E32B01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 50
100
150
200
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S07E32H01S | 05S07E32B01S
Appendix A-17
Groundwater Elevation
Hydrographs
05S07E20G01S and
05S07E27L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 50
100
150
200
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S07E20G01S | 05S07E27L01S
Appendix A-18
Groundwater Elevation
Hydrographs
05S07E14K02S and
05S07E12M01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 50
100
150
200
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S07E14K02S | 05S07E12M01S
Appendix A-19
Groundwater Elevation
Hydrographs
05S08E18G01S and
05S08E31C03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 50
100
150
200
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S08E18G01S | 05S08E31C03S
Appendix A-15
Groundwater Elevation
Hydrographs
05S06E20A02S and
05S06E13D01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
05S08E29G01S | 05S08E33D01S
Appendix A-21
Groundwater Elevation
Hydrographs
06S07E06J01S and
06S07E02D02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 50
100
150
200
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
06S07E06J01S | 06S07E02D02S
Appendix A-22
Groundwater Elevation
Hydrographs
06S08E05R03S and
06S08E12Q01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
06S08E05R03S | 06S08E12Q01S
Appendix A-23
Groundwater Elevation
Hydrographs
06S07E16A02S and
06S07E16R02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
06S07E16A02S | 06S07E16R02S
Appendix A-24
Groundwater Elevation
Hydrographs
06S08E22D02S and
06S08E25P04S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
06S08E22D02S | 06S08E25P04S
Appendix A-25
Groundwater Elevation
Hydrographs
06S08E19C02S and
06S07E26Q01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
06S08E19C02S | 06S07E26Q01S
Appendix A-26
Groundwater Elevation
Hydrographs
06S09E33K01S and
07S09E14C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
06S09E33K01S | 07S09E14C01S
Appendix A-27
Groundwater Elevation
Hydrographs
07S07E03D03S and
07S07E03A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S07E03D03S | 07S07E03A01S
Appendix A-28
Groundwater Elevation
Hydrographs
07S08E17A04S and
07S07E01C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S08E17A04S | 07S07E01C01S
Appendix A-29
Groundwater Elevation
Hydrographs
07S08E33B01S and
08S08E03L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S08E33B01S | 08S08E03L01S
Appendix A-30
Groundwater Elevation
Hydrographs
08S08E24L01S and
08S09E32G02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
08S08E24L01S | 08S09E32G02S
Appendix A-31
Groundwater Elevation
Hydrographs
07S08E10P01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S08E10P01S
Appendix A-32
Groundwater Elevation
Hydrographs
07S09E07J01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S09E07J01S
Appendix A-33
Groundwater Elevation
Hydrographs
07S09E08R01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S09E08R01S
Appendix A-34
Groundwater Elevation
Hydrographs
07S07E02G02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
-50
0 50
100
El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S07E02G02S
Appendix A-35
Groundwater Elevation
Hydrographs
07S09E18H01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S09E18H01S
Appendix A-36
Groundwater Elevation
Hydrographs
07S08E36B01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S08E36B01S
Appendix A-37
Groundwater Elevation
Hydrographs
07S09E26G03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S09E26G03S
Appendix A-38
Groundwater Elevation
Hydrographs
08S09E07M01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
08S09E07M01S
Appendix A-39
Groundwater Elevation
Hydrographs
08S09E07N03S and
08S09E07N04S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
08S09E07N03S | 08S09E07N04S
Appendix A-40
Groundwater Elevation
Hydrographs
07S09E30R01S and
07S09E30R02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-400
-350
-300
-250
-200
-150
-100
-50
0 El
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
07S09E30R01S | 07S09E30R02S
APPENDIX 4-B
INDIO SUBBASIN GROUNDWATER DEPENDENT ECOSYSTEMS STUDY
This page intentionally left blank.
Indio Groundwater Dependent Ecosystems 1 Woodard & Curran (0011492.02) November 2021
TECHNICAL MEMORANDUM
TO: Coachella Valley Water District
CC: Iris Priestaf, Todd Groundwater
PREPARED BY: William L. Medlin, PWS, ENV SP
REVIEWED BY: Rosalyn Prickett, AICP
DATE: November 2021
RE: Indio Subbasin Groundwater Dependent Ecosystems Study Identification of Groundwater Dependent Ecosystems (GDEs) are a required component of groundwater management planning under the Sustainable Groundwater Management Act (SGMA). SGMA defines GDEs as “ecological communities or species that depend on groundwater emerging from aquifers or on groundwater occurring near the ground surface” (23 CCR § 351(m)). This Technical Memorandum (memo) specifically focuses on potential GDEs identified within the Indio Subbasin of the Coachella Valley Groundwater Basin (project area).
1.INDIO GROUNDWATER BASIN ECOLOGICAL SETTING
An ecoregion is an area with generally similar ecosystems with similar quantity, quality, and type of environmental resources. Ecoregions are an important geospatial mapping system that are used by many local, state, and federal regulatory agencies and non-governmental organizations as a frame of reference for assessment and management of ecosystems across the United States (US). In the context of GDEs, it is important to consider the ecoregion where the GDEs are being assessed because biotic and abiotic processes may vary widely between localities.
The Indio Subbasin is located in southern California and sits between the San Jacinto Mountains to the west and the Little San Bernardino Mountains to the east. The project area encompasses multiple cities and unincorporated communities within Riverside County, California. A very small section in the southwestern extent of the Subbasin extends into San Diego County and Imperial County. The Subbasin sits entirely within the Sonoran Basin and Range (85) Level III ecoregion (USGS, EPA 2016). The Sonoran Basin and Range ecoregion consists of low mountains with large swaths of federal government-owned property and is generally hotter than the Mojave. Vegetation is typically adapted to prolonged drought and hot weather, along with accompanying extreme soil moisture and temperature regimes. Predominant natural vegetative communities are desert scrub including multiple species of cacti and creosotebush (Larrea tridentata) and microphyll woodlands that generally occupy desert washes or bajadas that carry occasional stormwater flow.
The project area covers four different Level IV ecoregions. Figure 1 (Attachment A) illustrates the general location of the Indio Subbasin in the context of the Ecoregions of California. The extreme southwestern extents of the Indio Subbasin occupy the Western Sonoran Mountain Woodland and Shrubland (81b) ecoregion. This montane transition area occurs at the western edge of the Sonoran Desert and is generally above 3,000 feet in elevation. The landscape typically consists of desert chapparal mixed with pinyon pine (Pinus monophylla) and California juniper (Juniperus californica) along with a few canyon live oak (Quercus chrysolepis) among the scattered granitic boulders. Native fan palm oases are found in some of the steeper canyons. Rocky mountainous slopes, cliffs, canyons, dry washes, and alluvial fans in this region provide habitat for the protected Peninsular bighorn sheep (Ovis canadensis nelsoni).
The western edges and tips of the basin extend into the Western Sonoran Mountains (81a) ecoregion. This area is characterized by erosional highlands of exposed bedrock dissected by dry washes that are subject to flash flooding.
Rainfall is infrequent in this ecoregion. Vegetative communities in this rocky terrain are typically creosotebush scrub
Indio Groundwater Dependent Ecosystems 2 Woodard & Curran (0011492.02) November 2021
with ocotillo (Fouquieria splendens) and cacti scattered throughout. Spring annual forbs are also abundant in this region.
The northern half of the basin consists of the Upper Coachella Valley and Hills (81e) ecoregion. This area is made up of alluvial and sand deposits surrounded by mountains to the east, west, and north. To the south, the valley slopes towards the Salton Sea and land use transitions to a vast agricultural landscape. However, the Mecca Hills and Indio Hills provide some rolling topography, and the Indio Hills have canyons where some native fan palm oases still persist.
Soils are typically hot and very dry. Certain sandy areas may provide suitable habitat for the protected Coachella Valley fringe-toed lizard (Uma inornata) as well as other rare or unusual species. Habitat fragmentation and loss by urban and suburban land development presents constant pressure on these protected species.
The southern half of the basin consists of the Imperial/Lower Coachella Valleys (81f) ecoregion. This area is largely comprised of the former Lake Cahuilla lakebed within the greater Salton Sink geologic formation. The region is mostly below sea level and contains significant areas of historically deposited silts and other river sediments that have made the area rich in agricultural productivity. Planted and fallow fields dominate the landscape and there is a complex system of irrigation for crop production. The Salton Sea sits at the low point of the Salton Trough and serves as the terminal drainage point for the Whitewater River/Coachella Valley Stormwater Channel (CVSC), New River, and Alamo River along with numerous other small tributaries, agricultural drains, and dry washes. The Salton Sea is an important ecological “stopover” habitat for a multitude of migratory birds and waterfowl that travel the Pacific Flyway; however, there are some persistent water quality problems that pose a threat to species such as eutrophication, contamination, and ever-increasing salinity.
According to United States Geological Survey (USGS) 7.5-minute topography, the approximate elevation of the western extent of the Indio Subbasin within the Santa Rosa Mountains is 3,000 above mean sea level and the approximate elevation of the southern extent of the basin along the shoreline of the Salton Sea is -230 feet below mean sea level. The principal surface drainage features within the Indio Subbasin are mainly comprised of larger, named urban stormwater channels, canals, creeks, agricultural drains, and dry washes that drain to the Whitewater River Stormwater Channel (which becomes the Coachella Valley Stormwater Channel in the lower portion of the valley).
Most of these major drainages generally flow east and south through the project area eventually emptying into the Salton Sea. It should also be noted that, according to the USGS topography mapping, there are many mapped springs in various locations throughout the basin. Refer to Figure 2 (Attachment A) for USGS 7.5-minute topography in the vicinity of the Indio groundwater basin.
2.THREATENED AND ENDANGERED SPECIES IN THE INDIO BASIN
As part of the GDEs assessment, Woodard & Curran conducted a preliminary review of special-status species within the Indio Subbasin. This study focuses on state and federal listed species designated as “threatened” and/or “endangered” by the California Department of Fish and Wildlife (CDFW) or the US Fish and Wildlife Service (USFWS).
Other listed or otherwise unlisted special status species were excluded from our evaluation. The purpose of this exercise was to support the determination of ecological value for potential GDEs within the Subbasin.
Much of the Indio Subbasin is covered by the Coachella Valley Multiple Species Habitat Conservation Plan (CVMSHCP). The plan was approved in September 2008 and most recently amended in August 2016. The CVMSHCP is administered by the Coachella Valley Conservation Commission (CVCC) and is designed to conserve regional sensitive ecological habitat and protected plant and animal species by coordinating project impacts and compensatory mitigation through the issuance of “take” permits for special-status species. The CVMSHCP plan area encompasses approximately 1.2 million acres within Riverside County, California. The small portions of the Indio Subbasin located within San Diego and Imperial Counties are not covered by the CVMSHCP. Refer to Figure 3 (Attachment A) for protected areas covering the Coachella Valley and the Indio Subbasin.
Indio Groundwater Dependent Ecosystems 3 Woodard & Curran (0011492.02) November 2021
Woodard & Curran conducted a literature review of the California Natural Diversity Database (CNDDB; CDFW 2020) for the Indio Subbasin. Additionally, Woodard & Curran reviewed the USFWS Critical Habitat Mapper and the Information, Planning and Consultation (IPaC) database for the area covering the Indio Subbasin. Refer to Figure 4 (Attachment A) for federal and state listed threatened and endangered species occurring within the Indio Subbasin according to CNDDB.
As part of the GDEs field assessment, thirteen (13) representative locations were surveyed in the field by a Woodard & Curran senior biologist to document the vegetative community and general habitat conditions from January 11 – 14, 2021. The field survey locations were selected during the preliminary desktop assessment of GDEs for the project area. Plant and wildlife species observed were documented during the field visit(s), and representative photographs were taken. Protocol-level or presence-absence surveys were not conducted as part of this scope of work. Refer to Figure 4 for a map of state and federal protected species potentially occurring within the Indio Subbasin. Table 1 below describes state and federal listed threatened and endangered species within the Indio Subbasin and whether they were observed during the field assessment.
Table 1. State and Federal Threatened and Endangered Species in Indio Subbasin.
Scientific Name
Common Name Status Habitat Potential to Occur Within
the Project Area
Reliance on
Groundwater
Individual(s)
Observed
Fauna
Ovis canadensis
nelsoni
Peninsular bighorn
sheep
USFWS: E
CDFW: T
CVMSHCP
coverage: yes
Open rocky slopes,
cliffs, canyons, dry
washes, and alluvial
fans.
Presumed extant based on
CNDDB (2020) data. Suitable
habitat exists within the project
area. USFWS-designated
critical habitat in project area.
Indirect. Species
relies on GDE
vegetation and
surface water that
may be supported
by groundwater.
No
Charadrius nivosus
nivosus
Western snowy
plover
USFWS: T
CDFW: none
CVMSHCP
coverage: no
Coastal beaches sand
spits, and salt pans;
freshwater and brackish
wetlands.
Presumed extant based on
USFWS IPaC (2021).
Potential habitat may exist
within the project area.
Indirect. Species
may nest in or
near wetlands
supported by
groundwater.
No
Empidonax traillii
extimus
southwestern willow
flycatcher
USFWS: E
CDFW: E
CVMSHCP
coverage: yes
Riparian and wetland
thickets.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Indirect. Species
relies on GDE
riparian
vegetation.
No
Polioptila
californica
californica
coastal California
gnatcatcher
USFWS: T
CDFW: none
CVMSHCP
coverage: no
Coastal sage scrub; dry
slopes, washes, mesas.
Presumed extant based on
CNDDB (2020) data.
However, habitat does not
appear to exist within the
project area.
No No
Rallus obsoletus
yumanensis
Yuma Ridgway’s rail
USFWS: E
CDFW: T
CVMSHCP
coverage: yes
Freshwater and alkali
marshes with shallow
open water areas.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Direct. Species
relies on shallow
wetlands that may
be supported by
groundwater.
No
Vireo bellii pusillus
least Bell’s vireo
USFWS: E
CDFW: E
CVMSHCP
coverage: yes
Willow-cottonwood
forest, streamside
thickets, and scrub oak.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Indirect. Species
relies on GDE
vegetation in
riparian areas for
breeding.
No
Gopherus agassizii
desert tortoise
USFWS: T
CDFW: T
CVMSHCP
coverage: yes
Sandy flats, dry
washes, and canyons
with enough soil for
burrowing.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Indirect. Species
may rely on GDE
vegetation.
No
Indio Groundwater Dependent Ecosystems 4 Woodard & Curran (0011492.02) November 2021
Scientific Name
Common Name Status Habitat Potential to Occur Within
the Project Area
Reliance on
Groundwater
Individual(s)
Observed
Uma inornata
Coachella Valley
fringe-toed lizard
USFWS: T
CDFW: E
CVMSHCP
coverage: yes
Sparsely vegetated
areas and dry washes
with fine, wind-blown
sand.
Presumed extant based on
CNDDB (2020) data. Suitable
habitat exists within the project
area. USFWS-designated
critical habitat in project area.
Indirect. Species
may rely on GDE
vegetation such
as mesquite.
No
Charina umbratica
southern rubber boa
USFWS: none
CDFW: T
CVMSHCP
coverage: no
Damp woodlands,
grassy meadows, and
sandy areas along
streams.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Indirect. Species
relies on GDE
vegetation in
woodlands and
moist sandy areas
near springs and
streams.
No
Anaxyrus
californicus
arroyo toad
USFWS: E
CDFW: none
CVMSHCP
coverage: yes
Washes, streams,
arroyos, and adjacent
riparian uplands;
shallow gravelly pools.
Presumed absent based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Direct and
indirect. Species
relies on
groundwater for
breeding and on
GDE vegetation
for foraging.
No
Batrachoseps
aridus
desert slender
salamander
USFWS: E
CDFW: E
CVMSHCP
coverage: no
Small permanent desert
springs and creeks with
riparian vegetation.
Presumed absent based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
N/A* No
Rana muscosa
southern mountain
yellow-legged frog
USFWS: E
CDFW: E
CVMSHCP
coverage: no
Sunny streambanks,
pools, and lake borders;
rocky streams fed by
snow melt.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Direct. Species
relies on surface
water features
that may be
supported by
groundwater.
No
Rana draytonii
California red-legged
frog
USFWS: T
CDFW: none
CVMSHCP
coverage: no
Ponds, wetlands, and
seeps and adjacent
grassy uplands.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Direct. Species
relies on surface
water features
that may be
supported by
groundwater.
No
Cyprinodon
macularius
desert pupfish
USFWS: E
CDFW: E
CVMSHCP
coverage: yes
Freshwater springs,
oases, and
saline/brackish pools;
also found in
agricultural drains.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
Direct. Species
relies on springs
and other surface
water features
that may be
supported by
groundwater.
No
Xyrauchen texanus
razorback sucker
USFWS: E
CDFW: E
CVMSHCP
coverage: no
Runs and pools of
freshwater rivers; warm,
shallow backwaters.
Presumed extant based on
CNDDB (2020) data.
However, habitat does not
appear to exist within the
project area. Additionally, the
literature suggests that no
naturally propagating
populations are left in
California.
Direct. Species
relies on rivers
and other surface
water features
that may be
supported by
groundwater.
No
Indio Groundwater Dependent Ecosystems 5 Woodard & Curran (0011492.02) November 2021
Scientific Name
Common Name Status Habitat Potential to Occur Within
the Project Area
Reliance on
Groundwater
Individual(s)
Observed
Dinacoma caseyi
Casey’s June beetle
USFWS: E
CDFW: none
CVMSHCP
coverage: no
Found in the desert in
coarse gravelly sands.
Presumed extant based on
CNDDB (2020) data. Suitable
habitat may exist within the
project area. USFWS-
designated critical habitat in
project area.
N/A* No
Euphydryas editha
quino
quino checkerspot
USFWS: E
CDFW: none
CVMSHCP
coverage: no
Chaparral; coastal sage
scrub with Plantago
spp.
Presumed absent based on
CNDDB (2020) data. Habitat
does not appear to exist within
the project area.
N/A* No
Flora
Astragalus
lentiginosus var.
coachellae
Coachella Valley
milk-vetch
USFWS: E
CDFW: none
CVMSHCP
coverage: yes
Sandy washes and
windblown dunes;
creosotebush scrub.
Presumed extant based on
CNDDB (2020) data. Suitable
habitat may exist within the
project area. USFWS-
designated critical habitat in
project area.
N/A* No
Astragalus
tricarinatus
triple-ribbed milk-
vetch
USFWS: E
CDFW: none
CVMSHCP
coverage: yes
Sandy, gravelly soils in
dry washes; gravelly
soils and granite at the
base of slopes.
Presumed extant based on
CNDDB (2020) data. Suitable
habitat may exist within the
project area.
N/A* No
Dodecahema
leptoceras
slender-hornded
spineflower
USFWS: E
CDFW: E
CVMSHCP
coverage: no
Old sandy benches or
floodplain terraces with
alluvial fan scrub just
below 2200 feet.
Presumed extant based on
CNDDB (2020) data. Potential
habitat may exist within the
project area.
N/A* No
E – Endangered
T – Threatened
N/A* - Reliance on groundwater unknown or otherwise not fully understood based on species omission from the Critical Species LookBook (2019).
Source: California Natural Diversity Database (CDFW 2020); USFWS Critical Habitat Mapper (2021); IPaC Trust Resources List (USFWS 2021).
3.GROUNDWATER DEPENDENT ECOSYSTEM ASSESSMENT
To support identification and protection of GDEs under SGMA, The Nature Conservancy (TNC) developed a 2018 report entitled Groundwater Dependent Ecosystems under the Sustainable Groundwater Management Act: Guidance for Preparing Groundwater Sustainability Plans. The GDEs Guidance suggests three criteria for assessment of the presence of GDEs: 1) Is the GDE underlain by a shallow unconfined or perched aquifer? 2) Is the depth to groundwater under the GDEs less than 30 feet? 3) Is the GDE located in an area known to discharge groundwater (e.g., springs/seeps)? These questions were considered during this assessment.
Preliminary Desktop Assessment
Using Geographic Information Systems (GIS), Woodard & Curran completed a preliminary desktop analysis of the California Natural Communities Commonly Associated with Groundwater (NCCAG) database for the project area. The NCCAG database represents a compilation of 48 publicly available state and federal environmental datasets that map wetlands, springs, seeps, and vegetation in California. The datasets were reviewed by a working group made up of multiple agencies and stakeholders including the California Department of Water Resources (DWR), CDFW, and TNC.
The current NCCAG database includes a set of GIS data for vegetative communities and a separate data set for wetlands which together are considered to be GDE indicators.
Indio Groundwater Dependent Ecosystems 6 Woodard & Curran (0011492.02) November 2021
Additional relevant environmental and hydrogeological GIS data sets were also reviewed as part of the desktop GDE assessment. Data resources included, but were not limited to, the following:
Aerial photography, including USDA-NRCS National Agricultural Imagery Program (NAIP) data and Microsoft Bing aerial imagery
United States Geological Services (USGS) 7.5-minute topography USGS Geological Survey Hydrologic Atlas: National Hydrography Dataset (NHD) and USGS Hydrologic Unit Code (HUC) 8-digit maps
USDA-NRCS Soil Surveys
United States Fish and Wildlife Service (USFWS) National Wetland Inventory (NWI) data USFWS Critical Habitat mapper
National Oceanic and Atmospheric Administration (NOAA) Essential Fish Habitat (EFH) mapper NRCS land use/land cover and conservation plan data
California DWR list of impaired (303d/305b) waters (latest approved) United States National Vegetation Classification (USNVC) data USFWS Information for Planning and Consultation (IPaC) online data California Department of Fish and Wildlife (CDFW) Biogeographic Information and Observation System (BIOS)
CDFW California Natural Diversity Database (CNDDB)
LIDAR (as available for the project counties)
A Subbasin map was created using these publicly available statewide and regional data layers to understand the extent of the NCCAG dataset within the project area. Refer to Figure 5 (Attachment A) for a map of GDE indicators within the project area. Once the basin map of GDE indicators was developed, Woodard & Curran then reviewed the project area and attempted to identify NCCAG polygons that appeared to be “probable GDEs” based on the following observations:
Presence of a USGS-mapped stream, spring, seep, or other waterbody Presence of USFWS National Wetlands Inventory (NWI) mapped wetlands Inundation visible on aerial imagery
Saturation visible on aerial imagery
Dense riparian and/or wetland vegetation visible on aerial imagery CNDDB and/or CNPS vegetative community data indicating a concentration of deep-rooted woody phreatophytes
California Protected Areas and/or Areas of Conservation Emphasis If an NCCAG polygon, or a portion thereof, included one or multiple of the above characteristics, then it was marked as a “Probable GDE” for further evaluation and field validation. NCCAG polygons that did not exhibit the above characteristics (or similar) were tentatively considered “Probable Non-GDEs” for purposes of the desktop study and would be subject to further review as part of the field study. Areas that appeared to consist primarily of wetland
Indio Groundwater Dependent Ecosystems 7 Woodard & Curran (0011492.02) November 2021
vegetation at drainages along the exposed seabed of the Salton Sea where the water level has receded from historic levels were classified as “Playa Wetland Communities” and were not included as GDEs at this point.
As part of our preliminary desktop GDE assessment, Woodard & Curran selected 15 separate locations for a GDE field assessment. These locations were selected from various representative NCCAG polygons across the project area based on apparent habitat type and accessibility for field survey. Refer to Figure 6 (Attachment A) for GDE field assessment locations.
GDE Field Assessment
Woodard & Curran completed a GDE field assessment study at representative locations throughout the Indio Subbasin.
Fifteen representative locations were originally selected based on geographic position within the project area, vegetative community/habitat type, land use, topography, and other environmental factors determined via remote sensing. Prior to field work, Woodard & Curran coordinated with the Indio Subbasin GSAs and other agencies, tribes, and landowners to review the selected GDE field assessment sites and property owner information, as well as confirm physical access to the sites. Survey permissions were obtained from the appropriate property owners for 13 field assessment sites prior to mobilization for the field effort.
The field study was conducted January 11 – 14, 2021. Woodard & Curran Senior Biologist Will Medlin and CVWD environmental staff (Mr. Luis Sanchez and Mr. Sergio Martinez) worked together to complete the field study. Sites one (1) through eight (8), ten (10) through twelve (12), and fourteen (14) and fifteen (15) were assessed in the field. Sites nine (9) and thirteen (13) were not accessible at the time of field deployment and have therefore been eliminated from this assessment and report.
Field observations were made at NCCAG-mapped seeps, springs, wetlands, and other riparian habitats to document plant communities, aquatic or semi-aquatic wildlife, indicators of surface and subsurface hydrology, soil-based evidence of a high-water table, and other relevant ecological and hydrological data. Soils were sampled to an approximate depth of between 12 – 20 inches (depending on restrictive layer) to determine moisture content and texture. The soil profile was assessed and classified based on color using a Munsell soil color chart. Photographs were taken in the four cardinal directions (north, east, south, west) at each GDE field assessment site to document the general habitat conditions. Field notes and additional photographs were taken of plant species, wildlife, and other relevant ecological data to support the GDE assessment at each site. Global Positioning System (GPS) points were also collected using a sub-meter Trimble Geo 7x GPS unit at each GDE field assessment site.
Upon completion of the GDE field assessment, Woodard & Curran refined the preliminary desktop GDE assessment data and revised the mapping for Probable GDEs and Probable Non-GDEs based on field observations and further research.
4.RESULTS
Using a combination of GIS desktop study and field assessments, Woodard & Curran attempted to assess 882 NCCAG-mapped polygons (136 NCCAG wetland and 746 NCCAG vegetation) within the project area. During the desktop assessment, 1,045 individual locations were visually reviewed and a determination of potential GDE status was made for a point on the landscape within the NCCAG polygon(s). Out of 1,045 assessment locations, 50 points (5%) were determined to be Probable GDEs. 932 points (89%) were determined to be Probable non-GDEs. 63 points (6%) were determined to be Playa Wetland Communities. Refer to Figure 7 (Attachment A) for the Preliminary GDE Assessment map.
Probable GDEs consisted of areas with apparent dense riparian and wetland vegetative communities along mapped drainage systems with potential for deep-rooted phreatophytes and/or visible, natural surface water flow. These
Indio Groundwater Dependent Ecosystems 8 Woodard & Curran (0011492.02) November 2021
Probable GDE clusters comprise hot or cold springs, seeps, and stream channels that convey snowmelt from the surrounding San Jacinto mountain front. The USGS has studied the Agua Caliente Spring, located in downtown Palm Springs, and determined that faulting of the basement rock provides a pathway for deep thermal water to rise from an underlying geothermal reservoir (USGS 2011). The USGS study assessed multiple thermal and non-thermal springs in Palm and Chino Canyons, determining that the hot springs are sourced from deep thermal water and not the regional aquifer. Typically, probable GDEs might be identified where monitoring well data for the regional aquifer indicated the depth to groundwater at 30 feet or less relative to the ground surface. The 30-foot threshold is based on scientific literature that indicates that groundwater levels extracted to greater than 30 feet below ground surface (bgs) may result in adverse impacts to ecosystem structure and function (Eamus et al., 2015). It should be noted that the areas within the Indio Subbasin where Probable GDEs were identified for this study do not have existing groundwater data that was available for review. Probable GDEs identified herein along the mountain-front may be associated with surface runoff, snowmelt, or springs and seeps from up-gradient sources.
Probable Non-GDEs consisted of areas that appeared incorrectly mapped based on current land development and land-use or that otherwise appeared to be dry upland areas, cultivated and/or flooded agricultural land, obvious human- made ponds, lakes, and other features, channelized drains, and where there were no other indicators of groundwater presence near the surface. It should be noted that dry washes, arroyos, bajadas, and other ephemeral conveyances where water only flows in response to heavy precipitation events were not classified as GDEs for purposes of this study.
Playa Wetland Community included areas of wetland habitat along the Salton Sea exposed seabed (playa) generally downstream of stream, agricultural drain, or stormwater channel outlets. The receding of the Salton Sea, due to reduced inflows, is exposing thousands of acres of playa each year. A 2020 Audubon report on Salton Sea wetlands explains that the irrigation ditches and other drainages “that used to drain directly into the Sea now spread out and slowly flow and pool on the exposed playa where new vegetation and wetlands now form” (Audubon California 2020).
Irrigation drainage to the Salton Sea was determined to be the major driver of these pockets of vegetation along the northern seashore. The irrigation drains are fed by collected groundwater from agricultural return flows; as they discharge to the playa, they can potentially create wetland habitats. The CVMSHCP identifies some of these playa wetlands as part of the CVSC/Delta Conservation Area, which includes the CVSC, agricultural drains emptying into the Salton Sea which may contain desert pupfish habitat, and areas along the seashore that contain sensitive natural communities (CVAG 2007). The CVMSHCP acknowledges that this habitat is sustained largely by agricultural runoff and outflow in the CVSC, but that maintenance of the drains and the flood control channel periodically modifies the habitat. .
For the field study, 13 representative locations were assessed for GDE indicators, functions, and values. Of the 13 sites reviewed in the field, one appeared to be a Probable GDE, nine appeared to be Probable Non-GDEs, and three appeared to be Playa Wetland Communities. The four GDE and Playa Wetland Community sites had deep-rooted woody riparian or wetland species growing there. Further, two sites (4 and 15) had either standing or flowing water observed at the surface. Table 2 below describes each of the field assessment sites in more detail.
9 Woodard & Curran November 2021 Indio Groundwater Dependent Ecosystems (0011492.02)
Table 2. Woodard & Curran GDE Field Assessment Sites in the Indio Subbasin.
GDE Field
Assessment
Site1
Latitude /
Longitude
NCCAG-
Mapped
Polygon?
NCCAG Vegetation /
Wetland Type*
Dominant Plant Species
Observed Field Assessment Notes
1 33.422221 N,
116.095600 W Yes
Vegetation –
Parkinsonia florida –
Olneya tesota
Parkinsonia florida, Larrea
tridentata, Encelia farinosa,
Lotus rigidus, Ferocactus
acanthodes,
Ericameria linearifolia,
Cylindropuntia ramosissima
Site is a dry creek/wash or bajada. Appears to only receive flow in response to major rainfall events. Soils are fine to coarse sands and gravel overlying bedrock and boulders. Some surface soil cracking observed in lower pools indicating temporary water presence. This location does not appear to be a GDE.
2 33.492767 N
116.199718 W Yes Vegetation – Alkaline
Mixed Scrub
Acacia greggii, Larrea
tridentata,
Parkinsonia florida,
Bromus tectorum
Site is a dry wash bajada habitat with no evidence of recent flooding or high groundwater. Cobble-gravel and boulders are strewn throughout the valley.
Soils are dry coarse sands and fine gravel over bedrock. Some birds and lizards observed at the data point location. This location does not appear to be a GDE.
3 33.502204 N
116.080565 W Yes
Wetland – Lacustrine,
Limnetic,
Unconsolidated
Bottom, Permanently
Flooded, Hyperhaline
Allenrolfea occidentalis
Site is an alkaline salt flat; soils have redoximorphic features and deep surface cracking indicating periodic saturation or inundation. Multiple songbirds were observed/heard at this site. This location appears to be a Playa Wetland Community.
4 33.524165 N
116.042841 W Yes
Wetland - Lacustrine,
Limnetic,
Unconsolidated
Bottom, Permanently
Flooded, Hyperhaline
Bolboschoenus robustus,
Typha domingensis,
Phragmites australis, Rumex
crispus, Tamarisk ramosissima,
Pluchea odorata, Polypogon
monspeliensis
Site is located near an agricultural drain that flows to the Salton Sea and consists of a dense emergent marsh wetland with standing water; soils are saturated and low-chroma with some organic content. Multiple songbirds, raptors, and wading birds observed at this location. Tadpoles observed in pools. This location appears to be a Playa Wetland Community. 5 33.511431 N
115.922835 W Yes
Wetland – Palustrine,
Emergent, Persistent,
Semi-permanently
Flooded
Tamarisk ramosissima,
Allenrolfea occidentalis,
Pluchea sericea,
Prosopis glandulosa
Site is located near the Salton Sea alongside a dense, low vegetated swale; the area appears to have burned in the recent past. No visible surface water; however, soils do have some redoximorphic concentrations indicating some periodic saturation or inundation. This location appears to be a Playa Wetland Community.
6 33.571216 N
116.096213 W Yes Vegetation - Alkali
Desert Scrub Atriplex lentiformis
Site is located just west of large agricultural drain and consists of alkaline salt scrub. Soils were dry and high chroma with no redoximorphic features. This location does not appear to be a GDE.
7 33.580616 N
116.007632 W Yes
Wetland – Palustrine,
Emergent, Persistent,
Seasonally Flooded
Tamarisk ramosissima
Site is within a basin created by the sloping land and the levee embankment for the Coachella Canal. The area likely receives and temporarily holds surface runoff. Soils are high chroma and very friable. Multiple songbirds heard/observed. This location does not appear to be a GDE. 8 33.655652 N
116.125904 W Yes Vegetation – Alkali
Desert Scrub N/A
Site is an active agricultural field with planted row crops. Site has active irrigation system and soils are wet due to watering. This location does not appear to be a GDE.
10 Woodard & Curran
November 2021
Indio Groundwater Dependent Ecosystems
(0011492.02)
GDE Field
Assessment
Site1
Latitude /
Longitude
NCCAG-
Mapped
Polygon?
NCCAG Vegetation /
Wetland Type*
Dominant Plant Species
Observed Field Assessment Notes
10 33.714428 N
116.262822 W Yes
Wetland – Riverine,
Unknown Perennial,
Unconsolidated
Bottom, Semi-
permanently Flooded
Xanthium strumarium, Atriplex
canescens, Distichlis spicata,
Tamarisk ramosissima, Ricinus
communis
Site is an alkaline salt scrub community located within the Coachella Valley Stormwater Channel. Soils are high chroma fine sands that are a little moist below six inches. This location does not appear to be a GDE. 11 33.591113 N
116.190892 W Yes Vegetation – Alkali
Desert Scrub N/A
Site is an active agricultural field with planted row crops. Site has active irrigation system and soils are wet due to watering. This location does not appear to be a GDE.
12 33.731912 N
116.430599 W Yes Vegetation – Desert
Willow
Acacia greggii, Larrea
tridentata, Ericameria
linearifolia, Dalea spinosa,
Bromus tectorum
Site is a creosote bush scrub habitat located in a valley above a small dam. No evidence of recent water flow or prolonged inundation. Soils are very dry, friable sands. This location does not appear to be a GDE. 14 33.853607 N
116.506499 W Yes
Wetland – Riverine,
Unknown Perennial,
Unconsolidated
Bottom, Semi-
permanently Flooded
Larrea tridentata, Atriplex
canescens, Encelia farinosa,
Artemisia sp.,
Site is a dry riverbed wash within the floodplain of the upper Whitewater River.
Some soil surface cracking observed, however no indicators of groundwater near surface. Soils are loose, dry sand. This location does not appear to be a GDE.
15 33.843826 N
116.604978 W Yes
Vegetation – Riparian
Mixed Hardwood;
Wetland – Palustrine,
Scrub-Shrub,
Seasonally Flooded
Platanus racemosa, Salix
exigua, Salix laevigata, Typha
domingensis,
Schoenoplectus americanus,
Erythranthe cardinalis
Site is located in a palustrine scrub-shrub and forested freshwater wetland seepage. Groundwater was visibly seeping at this data point. Soils were saturated to the surface and had some organic content. Multiple songbirds heard/observed. This location appears to be a GDE.
1 Note that GDE Field Assessment Sites #9 and 13 were not granted access by property-owners and are therefore not included in this table.
Indio Groundwater Dependent Ecosystems 11 Woodard & Curran (0011492.02) November 2021
5.CONCLUSIONS
Based on our preliminary assessment, few true GDEs appear to be present within the Indio Subbasin. Groundwater monitoring well data and groundwater contours shows depth to water at greater than 50 feet bgs for much of the northern and western portions of the Subbasin. However, the southeastern portion of the Subbasin between Thermal and the Salton Sea appears to indicate depth to water of less than 30 feet bgs in a shallow semi-perched aquifer zone.
These shallow groundwater levels in the southeastern Indio Subbasin may be affected by local groundwater replenishment facilities or through surface infiltration via agricultural irrigation or subsurface collection via agricultural tile drains.
Although the project area is heavily urbanized in the west and impacted by significant agricultural operations to the east, the major surface water drainageways still appear to have some pockets of riparian and wetland vegetative communities growing along them. The streams, hot and cold springs, palm oases, stormwater channels, canals, agricultural drains, and their associated riparian vegetative communities provide valuable ecological habitat for many animal species to shelter, feed, and breed. They also provide wildlife corridors for movement and migration through the urban and suburban and agricultural landscapes.
The SGMA Alternative Groundwater Sustainability Plan Bridge Document for the Indio Subbasin acknowledges that “there is no direct interconnection between surface water and groundwater” in the western Subbasin (Stantec 2016).
This finding is generally supported by the desktop and field assessments completed for this study, with the exception of several obvious mountain-front springs that support palm oases and wetland habitats. The few Probable GDEs present within the project area are located in the northwestern extents of the Indio Subbasin within canyons along streams that convey mountain-front runoff. It is undetermined whether these Probable GDEs depend on the regional groundwater table. These GDEs may rely on surface runoff, snowmelt, and springs and seeps from up-gradient sources to influence soil moisture requirements for vegetative communities. However, the three probable GDE clusters identified in this assessment are not likely directly affected by management of the primary aquifer in the Indio Subbasin.
The connection between these potential GDEs and the regional groundwater basin should be further investigated.
In the eastern Subbasin, this study identifies Playa Wetland Communities along the Salton Sea, but acknowledges that these habitats are likely dependent on collection and discharge of agricultural drain water. The collection of agricultural return flows into a surface water conveyance system results in the concentrated discharge of groundwater onto the Salton Sea playa, which spreads out and creates wetland habitats. It is important to note that DWR staff do not consider the subsurface tile drain system and the conveyance of agricultural runoff in the eastern Coachella Valley as a surface water system (DWR 2019). These wetland communities may not exist if it were not for the human-made tile drain system, coupled with the recession of the Salton Sea which creates large, exposed playa areas. There is a clear dynamic between the agricultural drains and the Playa Wetland Communities. Based on the 2020 Audubon study the drivers for wetlands creation are the surface drainage coupled with the recession of Salton Sea. The aerial extent of the playa wetlands appears to have grown over the last decade while drain flows were declining. The interconnection between these factors is uncertain and dependent on other state and federal entities’ management of the Salton Sea and its surface elevation. The aerial extent of Playa Wetland Communities may continue to change over time regardless of Indio Subbasin management activities. Further study of these habitats may be conducted to better assess their dependance on drain flows and/or underlying perched groundwater. Changes in the footprint of the Playa Wetland Communities should be explored through additional study and field validation, including monitoring of drain and surface water discharges and groundwater levels in the shallow perched aquifer. Additionally, collaboration with Salton Sea Authority and other entities focused on Salton Sea wetlands protection is warranted.
Indio Groundwater Dependent Ecosystems 12 Woodard & Curran (0011492.02) November 2021
6.REFERENCES
Audubon California. 2020. Identifying Existing Areas for Habitat Protection/Enhancement and Dust Suppression Projects on Salton Sea Exposed Playa. June.
https://ca.audubon.org/sites/default/files/saltonseaplayavegetationanalysisbrief_auduboncalifornia_v3.pdf Calflora. 2020. Information on Wild California Plants. https://www.calflora.org/ California Department of Water Resources. 2020. Summary of the “Natural Communities Commonly Associated with Groundwater” Dataset and Online Web Viewer.
California Department of Water Resources. 2019. Sustainable Groundwater Management Program Alternative Assessment Staff Report. Coachella Valley – Indio (Basin No. 7-021.01). Coachella Valley Water District.
California Native Plant Society. 2020. A Manual of California Vegetation Online. http://vegetation.cnps.org/ Coachella Valley Association of Governments (CVAG). 2007. Coachella Valley Multiple Species Habitat Conservation Plan and Natural Community Conservation Plan. Final Recirculated. September. https://www.cvmshcp.org/Plan_Documents_old.htm
Cowardin, L. M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deepwater habitats of the United States. U.S. Department of the Interior, Fish and Wildlife Service, Washington, D.C. 131pp.
Eamus, D., Zolfaghar, S., Villalobos-Vega, R., Cleverly, J. and Huete, A. 2015. Groundwater-dependent ecosystems:
recent insights from satellite and field-based studies. Hydrology and Earth System Sciences. 19(10), pp. 4229-4256.
Griffith, G.E., Omernik, J.M., Smith, D.W., Cook, T.D., Tallyn, E., Moseley, K., and Johnson, C.B., 2016, Ecoregions of California (poster): U.S. Geological Survey Open-File Report 2016–1021, with map, scale 1:1,100,000, http://dx.doi.org/10.3133/ofr20161021
Groundwater Resource Hub. 2020. Plant maximum-rooting depth database. The Nature Conservancy. https://groundwaterresourcehub.org/sgma-tools/gde-rooting-depths-database-for- gdes#:~:text=SGMA%20TOOLS,availability%20of%20other%20water%20sources .
Nature Conservancy. 2018. Groundwater Dependent Ecosystems under the Sustainable Groundwater Management Act: Guidance for Preparing Groundwater Sustainability Plans. January. https://groundwaterresourcehub.org/public/uploads/pdfs/GWR_Hub_GDE_Guidance_Doc_2-1-18.pdf NatureServe. 2021. NatureServe Explorer [web application]. NatureServe, Arlington, Virginia.
Available https://explorer.natureserve.org/ . (Accessed: February 28, 2021 and March 1, 2021).
Patten, M., McCaskie, G. and Unitt, P. 2003. Birds of the Salton Sea: status, biogeography, and ecology. University of California Press, Berkeley and Los Angeles, California.
Ritter, Matt. 2018. California Plants: A Guide to Our Iconic Flora.
Indio Groundwater Dependent Ecosystems 13 Woodard & Curran (0011492.02) November 2021
Rhode, M. M. 2016. Groundwater Dependent Ecosystems: From Identification to Management. The Nature Conservancy.
Rhode, M. M., Matsumoto, J. Howard, S. Liu, L. Riege, and E. J. Remson. 2018. Groundwater Dependent Ecosystems under the Sustainable Groundwater Management Act: Guidance for Preparing Groundwater Sustainability Plans. The Nature Conservancy, San Francisco, California.
Stewart, Jon Mark. 1993. Colorado Desert Wildflowers: a guide to flowering plants of the low desert, including the Coachella Valley, Anza-Borrego Desert, and portions of Joshua Tree National Monument.
Stantec. 2016. SGMA Alternative Groundwater Sustainability Plan – Bridge Document for the Indio Subbasin.
U.S. Army Corps of Engineers. 2008. Regional Supplement to the Corps of Engineers Wetland Delineation Manual:
Arid West Region (Version 2.0), ed. J. S. Wakeley, R.W. Lichvar, and C.V. Noble. ERDC/EL TR-08-28.
Vicksburg, MS; U.S. Army Engineer Research and Development Center.
United States Department of Agriculture, Natural Resources Conservation Service. 2021. PLANTS Database website. http://plants.usda.gov/java/
This page intentionally left blank.
Indio Groundwater Dependent Ecosystems Woodard & Curran (0011492.02) November 2021
ATTACHMENT A: FIGURES
This page intentionally left blank.
Riverside
San Diego Imperial
Sonoran Basin and RangeSouthern California Mountains
Mojave Basin and Range
Southern California/Northern Baja Coast
Le
g
e
n
d ±
Figure 1Project Location and EcoregionsIndio Groundwater BasinCoachella Valley Water District Figure
E
x
p
o
r
t
e
d
:
5 /
2 0
/
2 0
2 0
B
y
:
w
m
e
d
l
i
n
U
s
i
n
g
:
\
\
w
o
o
d
a
r
d
c
u
r
r
a
n
.
n
e
t
\
s
h
a
r
e
d
\
O
f
f
i
c
e
s
\
A
t
l
a
n
t
a
\
W
i
p
\
E
c
o
l
o
g
y
R
e
s
o
u
r
c
e
s
\
C
a
l
i
f
o
r
n
i
a
\
C
o
a
c
h
e
l
l
a
V
a
l
l
e
y
G
S
P
-
I
n
d
i
o
S
u
b
-
b
a
s
i
n
\
G
I
S
\
M
X
D
\
2 0
2 0
.
0 5
.
2 0
_
G
D
E
_
D
r
a
f
t
_
F
i
g
u
r
e
1 .
m
x
d
Project #: 0011492.02
Map Created: May 2020
0 5 102.5 MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaim er: This m ap is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the m ap or data contained herein shall be at the users’ sole risk. Data Sources: ESRI World Terrain Basemap; USEPA Level III Ecorgegions EPA Level III Ecoregion
Mojave Basin and Range
Sonoran Basin and Range
Southern California Mountains
Southern California/Northern Baja Coast
Indio Groundwater Basin
California Counties
1 inch = 5 m iles
Legend ±
Figure 2USGS TopographyIndio Groundwater BasinCoachella Valley Water District Figure Exported: 5/20/2020 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resourc es\California\Coachella Valley G
SP - Indio Sub-basin\G
IS\M
XD\2020.05.20_G
DE_Draft_Figure2.mxd
Project #: 0011492.02
Map Created: May 2020
0 5 102.5 MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:ESRI USGS 7.5 Minute Topography Indio Groundwater Basin
1 inch = 5 miles
Legend ±
Figure 3Coachella Valley Protected AreasIndio Groundwater BasinCoachella Valley Water District Figure Exported: 5/20/2020 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resourc es\California\Coachella Valley G
SP - Indio Sub-basin\G
IS\M
XD\2020.05.20_G
DE_Draft_Figure3.mxd
Project #: 0011492.02
Map Created: May 2020
0 5 102.5 MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:ESRI USGS 7.5 Minute Topography Indio Groundwater Basin
Coachella Valley Multiple Species Habitat Conservation Plan Boundary CVMSHCP Conservation Area Boundaries in Indio Basin
1 inch = 5 miles
Legend ±
Figure 4Threatened and Endangered Species Indio Groundwater BasinCoachella Valley Water District Figure Exported: 6/12/2020 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\San Pasqual GSP\GIS\MXD\2020.06.12_GDE_Draft_Figure4.mxd Project #: 0011492.02Map Created: June 2020
0 5 102.5 MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:BING Aerial Imagery; California Natural Diversity Database 2020.
Indio Groundwater Basin
1 inch = 5 miles
Threatened and Endangered Species
California red-legged frog
Casey's June beetle
Coachella Valley fringe-toed lizard
Coachella Valley milk-vetch
Peninsular bighorn sheep DPS
Yuma Ridgway's rail
coastal California gnatcatcher
desert pupfish
desert slender salamander
desert tortoise
least Bell's vireo
razorback sucker
slender-horned spineflower
southern mountain yellow-legged frog
southern rubber boa
southwestern willow flycatcher
triple-ribbed milk-vetch
Legend ±
Figure 5Agricultural DrainsIndio Groundwater BasinCoachella Valley Water District Figure Exported: 6/12/2020 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\San Pasqual GSP\GIS\MXD\2020.06.12_GDE_Draft_Figure5.mxd Project #: 0011492.02Map Created: June 2020
0 5 102.5 MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:BING Aerial Imagery; California Natural Diversity Database 2020.
Indio Groundwater Basin
Agricultural Drains 1 inch = 5 miles
Legend ±
Figure 6GDE IndicatorsIndio Groundwater BasinCoachella Valley Water District Figure Exported: 6/12/2020 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\San Pasqual GSP\GIS\MXD\2020.06.12_GDE_Draft_Figure6.mxd Project #: 0011492.02Map Created: June 2020
0 5 102.5 MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:Microsoft BING Aerial Imagery; CA DWR Natural Communities Commonly Associated with Groundwater.
Indio Groundwater Basin
NCCAG (Vegetation)
NCCAG (Wetlands)
1 inch = 5 miles
Legend ±
Figure 7Preliminary GDE AssessmentIndio Groundwater BasinCoachella Valley Water District Figure Exported: 6/10/2021 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\Coachella Valley G SP - Indio Sub-basin\G
IS\M
XD\2021.06.10_G
DE_Draft_Figure7.mxd
Project #: 0011492.02
Map Created: June 2021
0 5 102.5 MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:Microsoft BING Aerial Imagery; CA DWR Natural Communities Commonly Associated with Groundwater.
Indio Subbasin Boundaries
NCCAG (Vegetation)
NCCAG (Wetlands)
Probable GDE
Probable Non-GDE
Playa Wetland Community
1 inch = 5 miles
Legend ±
Figure 7aPreliminary GDE AssessmentIndio Groundwater BasinCoachella Valley Water District Figure Exported: 6/10/2021 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\Coachella Valley G SP - Indio Sub-basin\G
IS\M
XD\2021.06.10_G
DE_Draft_Figure7.mxd
Project #: 0011492.02
Map Created: June 2021
0 2 41MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:Microsoft BING Aerial Imagery; CA DWR Natural Communities Commonly Associated with Groundwater.
Indio Subbasin Boundaries
NCCAG (Vegetation)
NCCAG (Wetlands)
Probable GDE
Probable Non-GDE
Playa Wetland Community
1 inch = 2 miles
Legend ±
Figure 7bPreliminary GDE AssessmentIndio Groundwater BasinCoachella Valley Water District Figure Exported: 6/10/2021 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\Coachella Valley G SP - Indio Sub-basin\G
IS\M
XD\2021.06.10_G
DE_Draft_Figure7.mxd
Project #: 0011492.02
Map Created: June 2021
0 2 41MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:Microsoft BING Aerial Imagery; CA DWR Natural Communities Commonly Associated with Groundwater.
Indio Subbasin Boundaries
NCCAG (Vegetation)
NCCAG (Wetlands)
Probable GDE
Probable Non-GDE
Playa Wetland Community
1 inch = 2 miles
Legend ±
Figure 7cPreliminary GDE AssessmentIndio Groundwater BasinCoachella Valley Water District Figure Exported: 6/10/2021 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\Coachella Valley G SP - Indio Sub-basin\G
IS\M
XD\2021.06.10_G
DE_Draft_Figure7.mxd
Project #: 0011492.02
Map Created: June 2021
0 2 41MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:Microsoft BING Aerial Imagery; CA DWR Natural Communities Commonly Associated with Groundwater.
Indio Subbasin Boundaries
NCCAG (Vegetation)
NCCAG (Wetlands)
Probable GDE
Probable Non-GDE
Playa Wetland Community
1 inch = 2 miles
Legend ±
Figure 7dPreliminary GDE AssessmentIndio Groundwater BasinCoachella Valley Water District Figure Exported: 6/10/2021 By: wmedlin Using: \\woodardcurran.net\shared\Offices\Atlanta\Wip\Ecology Resources\California\Coachella Valley G SP - Indio Sub-basin\G
IS\M
XD\2021.06.10_G
DE_Draft_Figure7.mxd
Project #: 0011492.02
Map Created: June 2021
0 2 41MilesImperial, Riverside, and San Diego Counties, CA Third Party GIS Disclaimer: This map is for reference and graphical purposes only and should not be relied upon by third parties for any legal decisions. Any reliance upon the map or data contained herein shall be at the users’ sole risk. Data Sources:Microsoft BING Aerial Imagery; CA DWR Natural Communities Commonly Associated with Groundwater.
Indio Subbasin Boundaries
NCCAG (Vegetation)
NCCAG (Wetlands)
Probable GDE
Probable Non-GDE
Playa Wetland Community
1 inch = 2 miles
This page intentionally left blank.
Indio Groundwater Dependent Ecosystems Woodard & Curran (0011492.02) November 2021
ATTACHMENT B: PHOTOGRAPHIC LOG OF GDE FIELD ASSESSMENT SITES
This page intentionally left blank.
Indio GDE Field Assessment (0011492.02) Woodard & Curran June 2021
Photo Number: 1 View Direction: West Date: January 11, 2021 Description: Representative photograph taken of confirmed probable groundwater dependent ecosystem (NCCAG 2020).
Photo taken at GDE field assessment site 15.
Photo Number: 2 View Direction: Northwest Date: January 11, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken at GDE field assessment site 14.
Indio GDE Field Assessment (0011492.02) Woodard & Curran June 2021
Photo Number: 3 View Direction: North Date: January 11, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken at GDE field assessment site 12.
Photo Number: 4 View Direction: Southwest Date: January 12, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken GDE field assessment site 10.
Indio GDE Field Assessment (0011492.02) Woodard & Curran June 2021
Photo Number: 5 View Direction: North Date: January 12, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken GDE field assessment site 11.
Photo Number: 6 View Direction: Southwest Date: January 12, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken at GDE field assessment site 2.
Indio GDE Field Assessment (0011492.02) Woodard & Curran June 2021
Photo Number: 7 View Direction: North Date: January 12, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken at GDE field assessment site 6.
Photo Number: 8 View Direction: West Date: January 12, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken at GDE field assessment site 8.
Indio GDE Field Assessment (0011492.02) Woodard & Curran June 2021
Photo Number: 9 View Direction: South Date: January 13, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken at GDE field assessment site 1.
Photo Number: 10 View Direction: South Date: January 13, 2021 Description: Representative photograph taken of playa wetland community.
Photo taken at GDE field assessment site 5.
Indio GDE Field Assessment (0011492.02) Woodard & Curran June 2021
Photo Number: 11 View Direction: East Date: January 13, 2021 Description: Representative photograph taken of potential incorrectly mapped groundwater dependent ecosystem (NCCAG 2020). Photo taken at GDE field assessment site 7.
Photo Number: 12 View Direction: West Date: January 14, 2021 Description: Representative photograph taken of playa wetland community.
Photo taken at GDE field assessment site 4.
Indio GDE Field Assessment (0011492.02) Woodard & Curran June 2021
Photo Number: 13 View Direction: East Date: January 14, 2021 Description: Representative photograph taken of playa wetland community.
Photo taken at GDE field assessment site 3.
This page intentionally left blank.
APPENDIX 5-A
MUNICIPAL WATER DEMAND PROJECTION FOR 2022 INDIO SUBBASIN
ALTERNATIVE PLAN
This page intentionally left blank.
MUNICIPAL WATER DEMAND
PROJECTION FOR 2022 INDIO
SUBBASIN ALTERNATIVE PLAN
COACHELLA VALLEY WATER DISTRICT
COACHELLA WATER AUTHORITY
DESERT WATER AGENCY
INDIO WATER AUTHORITY
August 2021
2490 Mariner Square Loop, Suite 215
Alameda, CA 94501
www.toddgroundwater.com
In cooperation with:
This page intentionally left blank.
Indio Subbasin Alternative Plan Update 1 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
APPENDIX TABLE OF CONTENTS
Growth Forecast by Jurisdiction..........................................................................................................3 Coachella Valley Water District ................................................................................................................. 3 Coachella Water Authority ........................................................................................................................ 4 Desert Water Agency ................................................................................................................................ 6 Indio Water Agency ................................................................................................................................... 7 Growth Forecast for Customers outside GSA Domestic Water Service Areas ........................................9 Coachella Valley Water District ................................................................................................................. 9 Desert Water Agency .............................................................................................................................. 10 Housing Unit Forecast by Jurisdiction ............................................................................................... 17 Coachella Valley Water District ............................................................................................................... 17 Coachella Water Authority ...................................................................................................................... 18 Desert Water Agency .............................................................................................................................. 19 Indio Water Authority ............................................................................................................................. 20 Housing Unit Forecast for Customers Outside GSA Domestic Water Service Areas ............................. 21 Coachella Valley Water District ............................................................................................................... 21 Desert Water Agency .............................................................................................................................. 22
APPENDIX TABLES
Table 1. Coachella Valley Water District—Population .................................................................................. 3 Table 2. Coachella Valley Water District—Households ................................................................................ 3 Table 3. Coachella Valley Water District—Employees .................................................................................. 4 Table 4. Coachella Water Authority—Population ......................................................................................... 4 Table 5. Coachella Water Authority—Households ....................................................................................... 5 Table 6. Coachella Water Authority—Employees ......................................................................................... 5 Table 7. Desert Water Agency—Population ................................................................................................. 6 Table 8. Desert Water Agency—Households ................................................................................................ 6 Table 9. Desert Water Agency—Employees ................................................................................................. 7 Table 10. Indio Water Agency—Population .................................................................................................. 7 Table 11. Indio Water Agency—Households ................................................................................................ 8 Table 12. Indio Water Agency—Employees .................................................................................................. 8 Table 13. CVWD Other Water Systems—Population .................................................................................... 9 Table 14. CVWD Other Water Systems—Households .................................................................................. 9
Indio Subbasin Alternative Plan Update 2 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 15. CVWD Other Water Systems—Employees .................................................................................. 10 Table 16. DWA Other Water Systems—Population .................................................................................... 10 Table 17. DWA Other Water Systems—Households .................................................................................. 11 Table 18. DWA Other Water Systems—Employees .................................................................................... 11 Table 19. General Plan Land Uses and Maximum Dwelling Units .............................................................. 13 Table 20. Specific Plan Land Uses and Maximum Dwelling Units ............................................................... 15 Table 21. Coachella Valley Water District—Single Family Housing Units ................................................... 17 Table 22. Coachella Valley Water District—Multiple Family Housing Units ............................................... 17 Table 23. Coachella Water Authority—Single Family ................................................................................. 18 Table 24. Coachella Water Authority—Multiple Family ............................................................................. 18 Table 25. Desert Water Agency—Single Family Housing Units .................................................................. 19 Table 26. Desert Water Agency—Multiple Family Housing Units .............................................................. 19 Table 27. Indio Water Authority—Single Family Housing Units ................................................................. 20 Table 28. Indio Water Authority—Multiple Family Housing Units ............................................................. 20 Table 29. CVWD Other Water Systems—Single Family .............................................................................. 21 Table 30. CVWD Other Water Systems—Multiple Family .......................................................................... 21 Table 31. DWA Other Water Systems—Single Family Housing Units ......................................................... 22 Table 32. DWA Other Water Systems—Multiple Family Housing Units ..................................................... 22 Table 33. Baseline Water Demand Projection Before Conservation .......................................................... 23 Table 34. Baseline Water Demand Projection Before Conservation (Other Water Systems) .................... 23 Table 35. Water Loss Projection by GSA ..................................................................................................... 25 Table 36. Water Loss Projection by GSA (Other Water Systems) ............................................................... 25 Table 37. Passive Conservation Projection (Planning Area) ....................................................................... 27 Table 38. Passive Conservation Projection (Other Water Systems within Planning Area) ......................... 27 Table 39. Outdoor Water Use Adjustment by GSA (Within Planning Area) ............................................... 28 Table 40. Outdoor Water Use Adjustment (Other Water Systems within Planning Area) ......................... 28 Table 41. Water Supplied (Within Planning Area) ...................................................................................... 29 Table 42. Water Supplied (Other Water Systems within Planning Area) ................................................... 29
Indio Subbasin Alternative Plan Update 3 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
GROWTH FORECAST BY JURISDICTION
Coachella Valley Water District
Table 1. Coachella Valley Water District—Population
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 46,808 48,749 51,217 53,685 56,153 58,956 61,759 Coachella 28 29 31 32 34 39 44
Desert Hot Springs 2 2 2 2 2 3 4
Indian Wells 5,272 5,569 5,993 6,418 6,843 7,296 7,748
Indio 6,335 6,812 7,695 8,578 9,462 10,170 10,879
La Quinta 38,449 39,408 40,902 42,397 43,891 45,385 46,878 Palm Desert 49,350 51,716 54,747 57,778 60,810 64,124 67,439 Palm Springs 27 51 82 112 143 179 216
Rancho Mirage 18,145 20,073 21,941 23,809 25,677 27,486 29,295 Unincorporated Imperial 5,391 11,037 11,606 12,175 12,744 12,826 12,908 Unincorporated West 16,494 16,832 17,645 18,457 19,269 19,483 19,698 Unincorporated East 12,174 12,939 17,198 21,458 25,718 27,872 30,026 Total 198,475 213,217 229,059 244,901 260,746 273,819 286,894 Note: Does not include customers in CVWD service area served by other water systems
Table 2. Coachella Valley Water District—Households
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 14,592 15,953 17,089 18,226 19,362 20,582 21,803 Coachella 7 7 8 8 9 10 12
Desert Hot Springs 1 1 1 1 1 1 1
Indian Wells 2,690 2,772 2,848 2,923 2,998 3,074 3,150
Indio 2,449 2,764 3,144 3,524 3,904 4,193 4,482
La Quinta 14,532 15,210 15,888 16,565 17,242 17,896 18,550 Palm Desert 22,742 24,693 26,359 28,025 29,691 31,412 33,133 Palm Springs 16 34 48 63 77 93 109
Rancho Mirage 8,853 10,436 11,449 12,462 13,474 14,399 15,324 Unincorporated Imperial 1,785 4,529 4,868 5,208 5,548 5,587 5,625 Unincorporated West 6,667 6,856 7,184 7,512 7,840 7,908 7,977 Unincorporated East 2,492 2,964 4,751 6,539 8,326 9,407 10,488 Total 76,826 86,219 93,637 101,056 108,472 114,562 120,654 Note: Does not include customers in CVWD service area served by other water systems
Indio Subbasin Alternative Plan Update 4 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 3. Coachella Valley Water District—Employees
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 7,383 8,293 8,965 9,637 10,309 10,675 11,042 Coachella 2 2 2 2 2 2 2
Desert Hot Springs 2 19 27 34 41 43 44
Indian Wells 7,854 8,317 8,632 8,948 9,263 9,497 9,732
Indio 1,848 2,197 2,490 2,784 3,077 3,333 3,589
La Quinta 15,621 16,632 17,363 18,095 18,827 19,217 19,607 Palm Desert 39,780 41,533 43,021 44,508 45,996 48,185 50,375 Palm Springs 15 58 79 100 121 126 131
Rancho Mirage 16,550 17,642 18,435 19,228 20,021 20,508 20,995 Unincorporated Imperial 341 447 447 447 447 618 789
Unincorporated West 6,130 6,175 6,276 6,377 6,478 6,705 6,933 Unincorporated East 4,419 4,961 4,872 4,784 4,695 6,187 7,679 Total 99,945 106,276 110,609 114,944 119,277 125,096 130,918 Note: Does not include customers in CVWD service area served by other water systems
Coachella Water Authority
Table 4. Coachella Water Authority—Population
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 44,417 52,722 63,947 75,172 86,397 100,951 115,504 Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 44,417 52,722 63,947 75,172 86,397 100,951 115,504
Indio Subbasin Alternative Plan Update 5 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 5. Coachella Water Authority—Households
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 9,460 13,506 17,041 20,575 24,110 28,325 32,539 Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 9,460 13,506 17,041 20,575 24,110 28,325 32,539
Table 6. Coachella Water Authority—Employees
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 8,599 12,209 14,884 17,560 20,235 21,909 23,582 Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 8,599 12,209 14,884 17,560 20,235 21,909 23,582
Indio Subbasin Alternative Plan Update 6 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Desert Water Agency
Table 7. Desert Water Agency—Population
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 6,238 6,697 7,226 7,755 8,284 8,830 9,377 Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 46,325 48,447 50,724 53,002 55,279 57,875 60,472 Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 419 452 524 595 667 670 673
Unincorporated East 0 0 0 0 0 0 0
Total 52,982 55,596 58,474 61,352 64,230 67,375 70,522
Note: Does not include customers in DWA service area served by other water systems
Table 8. Desert Water Agency—Households
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 2,382 2,720 2,967 3,214 3,462 3,704 3,946 Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 22,657 24,306 25,528 26,749 27,971 29,293 30,615 Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 220 241 272 303 334 335 337
Unincorporated East 0 0 0 0 0 0 0
Total 25,259 27,267 28,767 30,266 31,767 33,332 34,898
Note: Does not include customers in DWA service area served by other water systems
Indio Subbasin Alternative Plan Update 7 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 9. Desert Water Agency—Employees
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 4,560 4,921 5,195 5,470 5,744 5,891 6,039 Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 30,748 33,086 34,606 36,127 37,647 38,220 38,794 Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 20 100 184 269 354 369 385
Unincorporated East 0 0 0 0 0 0 0
Total 35,328 38,107 39,985 41,866 43,745 44,480 45,218
Note: Does not include customers in DWA service area served by other water systems
Indio Water Agency
Table 10. Indio Water Agency—Population
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 83,147 87,097 93,474 99,852 106,229 111,790 117,351 La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 83,147 87,097 93,474 99,852 106,229 111,790 117,351
Indio Subbasin Alternative Plan Update 8 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 11. Indio Water Agency—Households
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 23,662 25,940 28,659 31,377 34,095 36,324 38,553
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 23,662 25,940 28,659 31,377 34,095 36,324 38,553
Table 12. Indio Water Agency—Employees
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 27,530 30,177 32,108 34,039 35,970 36,970 37,971
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 27,530 30,177 32,108 34,039 35,970 36,970 37,971
Indio Subbasin Alternative Plan Update 9 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
GROWTH FORECAST FOR CUSTOMERS OUTSIDE GSA DOMESTIC
WATER SERVICE AREAS
Coachella Valley Water District
Table 13. CVWD Other Water Systems—Population
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 1,748 1,748 1,748 1,748 1,748 1,748 1,748 Unincorporated West 7,180 7,440 7,956 8,472 8,988 9,092 9,196 Unincorporated East 13,662 13,662 13,662 13,662 13,662 13,662 13,662 Total 22,590 22,850 23,366 23,882 24,398 24,502 24,606
Table 14. CVWD Other Water Systems—Households
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 627 627 627 627 627 627 627
Unincorporated West 3,209 3,372 3,592 3,813 4,033 4,078 4,123 Unincorporated East 3,727 3,727 3,727 3,727 3,727 3,727 3,727 Total 7,563 7,726 7,946 8,167 8,387 8,432 8,477
Indio Subbasin Alternative Plan Update 10 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 15. CVWD Other Water Systems—Employees
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 221 221 221 221 221 221 221
Unincorporated West 2,832 3,002 3,191 3,380 3,570 3,847 4,124 Unincorporated East 2,740 2,740 2,740 2,740 2,740 2,740 2,740 Total 5,793 5,963 6,152 6,341 6,531 6,808 7,085
Desert Water Agency
Table 16. DWA Other Water Systems—Population
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 247 249 250 251 252 253 254
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 134 145 148 152 155 161 168
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 398 453 525 598 671 710 750
Unincorporated East 0 0 0 0 0 0 0
Total 779 847 923 1,001 1,078 1,124 1,172
Note: Does not include customers outside of the Planning Area
Indio Subbasin Alternative Plan Update 11 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 17. DWA Other Water Systems—Households
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 64 65 66 66 67 67 67
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 31 31 31 31 31 33 35
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 163 200 232 265 297 314 331
Unincorporated East 0 0 0 0 0 0 0
Total 258 296 329 362 395 414 433
Note: Does not include customers outside of the Planning Area
Table 18. DWA Other Water Systems—Employees
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 44 65 80 95 110 119 129
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 148 238 306 374 441 455 469
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 9 25 46 68 90 132 174
Unincorporated East 0 0 0 0 0 0 0
Total 201 328 432 537 641 706 772
Note: Does not include customers outside of the Planning Area
Indio Subbasin Alternative Plan Update 12 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
This page intentionally blank.
Indio Subbasin Alternative Plan Update 13 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
RESIDENTIAL GENERAL PLAN LAND USES
Table 19. General Plan Land Uses and Maximum Dwelling Units Jurisdiction
(Data Adopted) City Land Use SCAG Land Use Description
(*Adjusted)
Maximum
Dwelling
Units/Acre
Cathedral City
(2009)
RE Low Density Single Family Residential 2
RL Medium Density Single Family Residential 4
RR Mixed Residential 6
RM Mixed Residential 10
RMH Mixed Residential 20
DTC Mixed Residential and Commercial 20
RH Mixed Multi-Family Residential 24
MU-N Mixed Residential and Commercial 25
MU-U Mixed Residential and Commercial 45
Coachella
(2015)
Rural Rancho Rural Residential 1
Suburban Neighborhood Medium Density Single Family Residential 8 Resort District Other Commercial 8
General Neighborhood Mixed Residential 25
Urban Neighborhood Multi-Family Residential 38
Neighborhood Center Mixed Residential and Commercial 40 Urban Employment Center General Office Use 65
Downtown Center Commercial-Oriented
Residential/Commercial Mixed Use 65
Indian Wells
(2007)
Very Low Density
Residential Low Density Single Family Residential 3
Low Density Residential Medium Density Single Family Residential 4 Medium Density Residential Medium Density Single Family Residential 7 Medium High Density
Residential Multi-Family Residential 12
Indio
(2007)
Country Estates Low Density Single Family Residential 1 Country Estates Transition Low Density Single Family Residential 1 Equestrian Estates Low Density Single Family Residential 2 Residential—Low Medium Density Single Family Residential 4 Residential—Medium Multi-Family Residential 8
Residential—High Multi-Family Residential 20
La Quinta
(2016)
LDR Low Density Single Family Residential 4
MHDR Multi-Family Residential 16
VC Mixed Residential and Commercial 16
Palm Desert
(2016)
R Rural Residential 1
CS *Medium Density Single Family Residential 8
GC&R Mixed Residential and Commercial 8
ST Mixed Residential 10
RE Other Commercial 10
Indio Subbasin Alternative Plan Update 14 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 19. General Plan Land Uses and Maximum Dwelling Units Jurisdiction
(Data Adopted) City Land Use SCAG Land Use Description
(*Adjusted)
Maximum
Dwelling
Units/Acre
SR Commercial-Oriented
Residential/Commercial Mixed Use 15
N Commercial-Oriented
Residential/Commercial Mixed Use 15
RR Commercial-Oriented
Residential/Commercial Mixed Use 15
TC Mixed Residential 40
DT Commercial-Oriented
Residential/Commercial Mixed Use 40
Palm Springs
(2007)
ER Low Density Single Family Residential 2
VLDR *Medium Density Single Family Residential 4
LDR *Medium Density Single Family Residential 6
SH Hotels and Motels 10
MDR Mixed Residential 15
MU Mixed Residential and Commercial 15
HDR Multi-Family Residential 30
TRC *Mixed Residential and Commercial 30
HDR Mixed Residential and Commercial 30
CBD Mixed Residential and Commercial 30
Rancho Mirage
(2017)
R-E Low Density Single Family Residential 1
R-L-2 *Low Density Single Family Residential 2
R-L-3 *Low Density Single Family Residential 3
R-M *Low Density Single Family Residential 4
R-H Multi-Family Residential 9
MHP Mobile Homes and Trailer Parks 9
M-U Mixed Residential and Commercial 28
Riverside County
(2015)
VLDR Low Density Single Family Residential 1
RC-VLDR Low Density Single Family Residential 1
LDR Low Density Single Family Residential 2
RC-LDR Low Density Single Family Residential 2
MDR Medium Density Single Family Residential 5
MHDR Mixed Residential 8
HDR Mixed Residential 14
VHDR Multi-Family Residential 20
HHDR Multi-Family Residential 40
Imperial County
RR *Low Density Single Family Residential 1
MHP Mobile Homes and Trailer Parks 8
RA Multi-Family Residential 30
RC Mixed Residential 30
Indio Subbasin Alternative Plan Update 15 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
RESIDENTIAL SPECIFIC PLAN LAND USES
Table 20. Specific Plan Land Uses and Maximum Dwelling Units Jurisdiction
(Date Adopted) Specific Plan Name City Land Use
Code
SCAG Land Use Code
(*Adjusted)
Maximum
Dwelling
Units/Acre
Cathedral City
North City Extended
Specific Plan
MU-N Mixed Residential and
Commercial 25
MU-U Mixed Residential and
Commercial 45
North City Specific Plan
RE Low Density Single Family
Residential 2
MU-N Mixed Residential and
Commercial 25
MU-U Mixed Residential and
Commercial 45
Coachella Eagle Falls Specific Plan SFR Low Density Residential 10 Indio
Central Highway 111
Corridor Specific Plan RHD *Multi-Family Residential 20 Fred Young Specific
Plan
Multi-Family
Residential Multi-Family Residential 20
Mixed
Residential *Mixed Residential 20
Gateway Conceptual SP
RVL *Medium Density Single Family
Residential 5
RVM *Medium Density Single Family
Residential 10
MU Mixed Residential 20
Indian Palm Country
Club Conceptual
Specific Plan
Residential—
Low
Medium Density Single Family
Residential 4
Outdoor Resort
Country Club Specific
Plan
Lot Area Mobile Homes and Trailer Parks 12
La Quinta
SP 01-053
Puerta Azul MHDR Multi-Family Residential 16
SP 03-069
Watermark Villas RMH *Multi-Family Residential 12
SP 05-076
Casa La Quinta RMH *Multi-Family Residential 16
SP 121E La Quinta
Resort & Club
RL Low Density Residential 4
RM Low Density Residential 8
Palm Springs College Park
Very Low
Density
Residential
*Low Density Single Family
Residential 4
Low Density
Residential
*Medium Density Single Family
Residential 6
Indio Subbasin Alternative Plan Update 16 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 20. Specific Plan Land Uses and Maximum Dwelling Units Jurisdiction
(Date Adopted) Specific Plan Name City Land Use
Code
SCAG Land Use Code
(*Adjusted)
Maximum
Dwelling
Units/Acre
Medium
Density
Residential
Mixed Residential 15
Section 14 MBR Multi-Family Residential 8
Section 15 MR Multi-Family Residential 15
Section 16 HR Multi-Family Residential 30
Rancho Mirage Monterey Specific Plan
LDR *Low Density Single Family
Residential 2
MDR *Medium Density Single Family
Residential 4
HDR *Multi-Family Residential 12
Indio Subbasin Alternative Plan Update 17 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
HOUSING UNIT FORECAST BY JURISDICTION
Coachella Valley Water District
Table 21. Coachella Valley Water District—Single Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 12,491 13,917 15,064 16,160 17,178 18,130 18,844 Coachella 5 6 6 7 7 8 9
Desert Hot Springs 0 0 0 0 0 1 1
Indian Wells 4,405 4,534 4,650 4,758 4,860 4,949 5,016
Indio 2,121 2,444 2,820 3,178 3,512 3,732 3,898
La Quinta 20,357 21,273 22,157 22,999 23,781 24,439 24,933 Palm Desert 24,666 27,284 29,438 31,495 33,406 35,124 36,414 Palm Springs 15 38 56 73 89 105 117
Rancho Mirage 11,538 13,647 14,946 16,188 17,340 18,256 18,944 Unincorporated Imperial 2,142 5,849 6,292 6,714 7,106 7,145 7,175 Unincorporated West 6,562 6,774 7,130 7,470 7,786 7,843 7,886 Unincorporated East 1,322 1,778 3,443 5,033 6,510 7,288 7,871 Total 85,624 97,544 106,002 114,075 121,575 127,020 131,108 Note: Does not include customers in CVWD service area served by other water systems
Table 22. Coachella Valley Water District—Multiple Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 5,553 5,809 6,067 6,376 6,763 7,320 8,115 Coachella 2 2 2 2 2 3 4
Desert Hot Springs 0 0 0 0 0 0 1
Indian Wells 602 626 652 682 721 773 847
Indio 845 903 987 1,088 1,215 1,344 1,528
La Quinta 2,821 2,986 3,184 3,422 3,720 4,105 4,654
Palm Desert 11,341 11,811 12,295 12,875 13,602 14,608 16,043 Palm Springs 9 14 18 23 29 38 51
Rancho Mirage 2,371 2,750 3,042 3,392 3,830 4,367 5,132 Unincorporated Imperial 703 1,370 1,469 1,588 1,738 1,761 1,793 Unincorporated West 2,300 2,339 2,418 2,514 2,635 2,668 2,716 Unincorporated East 1,520 1,602 1,976 2,425 2,987 3,442 4,091 Total 28,067 30,212 32,110 34,387 37,242 40,429 44,975
Note: Does not include customers in CVWD service area served by other water systems
Indio Subbasin Alternative Plan Update 18 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Coachella Water Authority
Table 23. Coachella Water Authority—Single Family
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 7,413 11,062 14,135 17,070 19,795 22,623 24,746 Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 7,413 11,062 14,135 17,070 19,795 22,623 24,746
Table 24. Coachella Water Authority—Multiple Family
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 2,655 3,312 4,001 4,829 5,866 7,522 9,884
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 2,655 3,312 4,001 4,829 5,866 7,522 9,884
Indio Subbasin Alternative Plan Update 19 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Desert Water Agency
Table 25. Desert Water Agency—Single Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 2,039 2,393 2,643 2,881 3,103 3,291 3,433 Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 21,214 23,353 24,880 26,338 27,692 28,968 29,926 Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 216 241 274 306 336 337 338
Unincorporated East 0 0 0 0 0 0 0
Total 23,469 25,987 27,797 29,525 31,131 32,596 33,697
Note: Does not include customers in DWA service area served by other water systems
Table 26. Desert Water Agency—Multiple Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 906 970 1,026 1,093 1,178 1,288 1,446
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 13,459 13,843 14,186 14,597 15,113 15,860 16,925 Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 76 80 88 97 108 109 110
Unincorporated East 0 0 0 0 0 0 0
Total 14,441 14,893 15,300 15,787 16,399 17,257 18,481
Note: Does not include customers in DWA service area served by other water systems
Indio Subbasin Alternative Plan Update 20 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Indio Water Authority
Table 27. Indio Water Authority—Single Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 20,486 22,824 25,511 28,078 30,461 32,163 33,441
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 20,486 22,824 25,511 28,078 30,461 32,163 33,441
Table 28. Indio Water Authority—Multiple Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 8,159 8,580 9,183 9,907 10,814 11,810 13,232
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 0 0 0 0 0 0 0
Unincorporated East 0 0 0 0 0 0 0
Total 8,159 8,580 9,183 9,907 10,814 11,810 13,232
Indio Subbasin Alternative Plan Update 21 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
HOUSING UNIT FORECAST FOR CUSTOMERS OUTSIDE
GSA DOMESTIC WATER SERVICE AREAS
Coachella Valley Water District
Table 29. CVWD Other Water Systems—Single Family
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 753 753 753 753 753 753 753
Unincorporated West 3,158 3,342 3,581 3,809 4,022 4,059 4,087 Unincorporated East 1,977 1,977 1,977 1,977 1,977 1,977 1,977 Total 5,888 6,072 6,311 6,539 6,752 6,789 6,817
Table 30. CVWD Other Water Systems—Multiple Family
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 0 0 0 0 0 0 0
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 0 0 0 0 0 0 0
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 247 247 247 247 247 247 247
Unincorporated West 1,107 1,140 1,194 1,258 1,339 1,361 1,392 Unincorporated East 2,274 2,274 2,274 2,274 2,274 2,274 2,274 Total 3,628 3,661 3,715 3,779 3,860 3,882 3,913
Indio Subbasin Alternative Plan Update 22 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Desert Water Agency
Table 31. DWA Other Water Systems—Single Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 51 52 53 53 54 54 54
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 29 29 29 29 29 31 33
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 160 202 237 271 302 316 327
Unincorporated East 0 0 0 0 0 0 0
Total 240 283 319 353 385 401 414
Table 32. DWA Other Water Systems—Multiple Family Housing Units Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Cathedral City 0 0 0 0 0 0 0
Coachella 0 0 0 0 0 0 0
Desert Hot Springs 28 28 28 28 29 29 29
Indian Wells 0 0 0 0 0 0 0
Indio 0 0 0 0 0 0 0
La Quinta 0 0 0 0 0 0 0
Palm Desert 0 0 0 0 0 0 0
Palm Springs 18 18 18 18 18 20 21
Rancho Mirage 0 0 0 0 0 0 0
Unincorporated Imperial 0 0 0 0 0 0 0
Unincorporated West 56 64 72 81 93 101 113
Unincorporated East 0 0 0 0 0 0 0
Total 102 110 118 127 140 150 163
Indio Subbasin Alternative Plan Update 23 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
BASELINE WATER DEMAND PROJECTION BEFORE CONSERVATION
Table 33. Baseline Water Demand Projection Before Conservation (AFY) GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 47,369 53,964 58,643 63,111 67,259 70,271 72,532 CVWD Multiple Family 5,623 6,043 6,439 6,913 7,508 8,140 9,040 CVWD CII 6,087 6,473 6,737 7,001 7,264 7,619 7,973
CVWD Landscape 28,328 31,803 34,396 36,996 39,609 41,763 43,931 CVWD Other 1,067 1,197 1,295 1,393 1,491 1,572 1,654
CWA Single Family 4,060 6,060 7,743 9,350 10,843 12,392 13,555 CWA Multiple Family 710 886 1,071 1,292 1,570 2,013 2,645 CWA CII 730 1,036 1,264 1,491 1,718 1,860 2,002
CWA Landscape 589 841 1,061 1,281 1,501 1,764 2,026
CWA Other 12 17 22 26 31 36 41
DWA Single Family 15,060 16,675 17,837 18,946 19,977 20,917 21,623 DWA Multiple Family 1,669 1,721 1,768 1,825 1,895 1,995 2,136 DWA CII 9,220 9,945 10,435 10,926 11,416 11,608 11,801
DWA Landscape 3,388 3,654 3,852 4,050 4,248 4,455 4,663 DWA Other 0 0 0 0 0 0 0
IWA Single Family 10,854 12,092 13,516 14,876 16,139 17,041 17,717 IWA Multiple Family 1,753 1,843 1,973 2,128 2,323 2,537 2,843 IWA CII 2,774 3,041 3,235 3,430 3,624 3,725 3,826
IWA Landscape 4,982 5,462 6,034 6,606 7,178 7,648 8,117 IWA Other 4 5 5 6 6 6 7
Table 34. Baseline Water Demand Projection Before Conservation (Other Water Systems) (AFY) GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 2,442 2,518 2,618 2,712 2,800 2,816 2,828 CVWD Multiple Family 525 529 537 547 558 561 566
CVWD CII 351 361 372 384 395 412 429
CVWD Landscape 501 513 528 544 559 562 565
CVWD Other 117 120 124 127 131 132 132
DWA Single Family 76 90 101 112 122 127 131
DWA Multiple Family 32 35 37 41 44 47 52
DWA CII 100 163 215 268 320 352 385
DWA Landscape 11 12 14 15 16 17 18
DWA Other 2 2 2 2 3 3 3
Indio Subbasin Alternative Plan Update 24 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
This page intentionally blank.
Indio Subbasin Alternative Plan Update 25 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
WATER LOSS PROJECTION
Table 35. Water Loss Projection by GSA (AFY)
Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Coachella Valley
Water District 10,420 11,714 12,474 13,194 13,873 14,318 14,730 Coachella Water Authority 371 529 654 774 888 1,021 1,147 Desert Water Agency 2,820 3,041 3,142 3,236 3,323 3,412 3,493 Indio Water Authority 1,059 1,161 1,257 1,348 1,434 1,495 1,553 Note: Includes only customers within Planning Area. Does not include customers served by other water systems
Table 36. Water Loss Projection by GSA (Other Water Systems) (AFY) Jurisdiction 2016 2020 2025 2030 2035 2040 2045
Coachella Valley
Water District 872 892 901 908 914 900 885
Desert Water Agency 25 29 32 34 37 38 39
Note: Includes only customers within the Planning Area
Indio Subbasin Alternative Plan Update 26 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
This page intentionally blank.
Indio Subbasin Alternative Plan Update 27 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
ADJUSTMENT FACTORS
Table 37. Passive Conservation Projection (Planning Area) (AFY) GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 0 382 993 1,371 1,649 1,842 1,981
CVWD Multiple Family 0 79 186 266 342 415 494
CVWD CII 0 38 117 169 213 255 292
CVWD Landscape 0 0 0 0 0 0 0
CVWD Other 0 0 0 0 0 0 0
CWA Single Family 0 94 277 421 543 662 756
CWA Multiple Family 0 20 52 82 116 166 232
CWA CII 0 4 16 26 36 44 52
CWA Landscape 0 0 0 0 0 0 0
CWA Other 0 0 0 0 0 0 0
DWA Single Family 0 84 214 293 349 392 424
DWA Multiple Family 0 32 74 102 126 149 171
DWA CII 0 14 42 61 78 90 100
DWA Landscape 0 0 0 0 0 0 0
DWA Other 0 0 0 0 0 0 0
IWA Single Family 0 152 396 548 660 740 797
IWA Multiple Family 0 35 83 116 148 179 212
IWA CII 0 11 34 50 64 75 84
IWA Landscape 0 0 0 0 0 0 0
IWA Other 0 0 0 0 0 0 0
Note: Does not include customers served by other water systems
Table 38. Passive Conservation Projection (Other Water Systems within Planning Area) (AFY) GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 0 30 75 100 116 125 131
CVWD Multiple Family 0 16 37 50 60 68 73
CVWD CII 0 2 6 9 12 14 16
CVWD Landscape 0 0 0 0 0 0 0
CVWD Other 0 0 0 0 0 0 0
DWA Single Family 0 1 4 5 6 7 7
DWA Multiple Family 0 0 1 1 2 2 3
DWA CII 0 0 0 1 1 1 2
DWA Landscape 0 0 0 0 0 0 0
DWA Other 0 0 0 0 0 0 0
Note: Includes only customers within the Planning Area
Indio Subbasin Alternative Plan Update 28 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
Table 39. Outdoor Water Use Adjustment by GSA (Within Planning Area) (AFY) GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 0 944 1,615 2,254 2,849 3,280 3,604
CVWD Multiple Family 0 31 60 95 138 185 251
CVWD CII 0 52 88 124 160 208 256
CVWD Landscape 0 931 1,625 2,322 3,021 3,599 4,179
CVWD Other 0 0 0 0 0 0 0
CWA Single Family 0 214 393 565 725 890 1,015
CWA Multiple Family 0 6 13 21 32 48 71
CWA CII 0 38 67 95 124 142 159
CWA Landscape 0 67 126 185 244 315 385
CWA Other 0 0 0 0 0 0 0
DWA Single Family 0 239 412 576 729 868 973
DWA Multiple Family 0 8 15 23 34 48 69
DWA CII 0 179 300 422 543 590 638
DWA Landscape 0 71 124 177 230 286 342
DWA Other 0 0 0 0 0 0 0
IWA Single Family 0 154 331 500 657 769 853
IWA Multiple Family 0 6 16 27 41 56 78
IWA CII 0 51 88 126 163 182 202
IWA Landscape 0 129 282 435 588 714 840
IWA Other 0 0 0 0 0 0 0
Note: Includes only customers within Planning Area. Does not include customers served by other water systems
Table 40. Outdoor Water Use Adjustment (Other Water Systems within Planning Area) (AFY) GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 0 8 19 30 39 41 42
CVWD Multiple Family 0 1 2 4 5 6 7
CVWD CII 0 12 24 37 50 69 87
CVWD Landscape 0 2 6 9 12 13 13
CVWD Other 0 0 0 0 0 0 0
DWA Single Family 0 2 4 5 7 7 8
DWA Multiple Family 0 0 0 1 1 1 1
DWA CII 0 9 16 23 30 34 39
DWA Landscape 0 1 1 2 2 2 3
DWA Other 0 0 0 0 0 0 0
Note: Includes only customers within the Planning Area
Indio Subbasin Alternative Plan Update 29 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
FINAL DEMAND PROJECTIONS BY JURISDICTION
Table 41. Water Supplied (Within Planning Area) (AFY)
GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 47,369 52,638 56,036 59,485 62,762 65,150 66,947 CVWD Multiple Family 5,623 5,933 6,193 6,553 7,028 7,540 8,295 CVWD CII 6,087 6,382 6,532 6,708 6,891 7,156 7,426
CVWD Landscape 28,328 30,873 32,770 34,674 36,587 38,165 39,751 CVWD Other 1,067 1,197 1,295 1,393 1,491 1,572 1,654
CVWD Losses 10,420 11,714 12,474 13,194 13,873 14,318 14,730 CWA Single Family 4,060 5,752 7,072 8,364 9,575 10,840 11,785 CWA Multiple Family 710 860 1,005 1,189 1,422 1,799 2,342 CWA CII 730 994 1,181 1,370 1,558 1,674 1,790
CWA Landscape 589 774 935 1,096 1,257 1,449 1,641
CWA Other 12 17 22 26 31 36 41
CWA Losses 371 529 654 774 888 1,021 1,147
DWA Single Family 15,060 16,352 17,211 18,078 18,899 19,657 20,226 DWA Multiple Family 1,669 1,682 1,680 1,699 1,735 1,797 1,896 DWA CII 9,220 9,752 10,093 10,443 10,795 10,928 11,063
DWA Landscape 3,388 3,582 3,727 3,872 4,018 4,170 4,322 DWA Other 0 0 0 0 0 0 0
DWA Losses 2,820 3,041 3,142 3,236 3,323 3,412 3,493
IWA Single Family 10,854 11,787 12,790 13,828 14,822 15,532 16,067 IWA Multiple Family 1,753 1,802 1,875 1,985 2,135 2,303 2,553 IWA CII 2,774 2,979 3,113 3,254 3,397 3,468 3,540
IWA Landscape 4,982 5,333 5,752 6,171 6,590 6,934 7,277 IWA Other 4 5 5 6 6 6 7
IWA Losses 1,059 1,161 1,257 1,348 1,434 1,495 1,553
Note: Includes only customers within Planning Area. Does not include customers served by other water systems
Table 42. Water Supplied (Other Water Systems within Planning Area) (AFY) GSA Sector 2016 2020 2025 2030 2035 2040 2045
CVWD Single Family 2,442 2,480 2,523 2,583 2,645 2,650 2,654 CVWD Multiple Family 525 513 499 493 493 488 486
CVWD CII 351 347 342 337 334 330 326
CVWD Landscape 501 510 523 535 547 549 552
CVWD Other 117 120 124 127 131 132 132
CVWD Losses 872 892 901 908 914 900 885
DWA Single Family 76 86 94 102 109 113 116
DWA Multiple Family 32 34 36 39 42 44 48
DWA CII 100 155 199 244 289 317 344
DWA Landscape 11 12 12 13 14 15 15
DWA Other 2 2 2 2 3 3 3
DWA Losses 25 29 32 34 37 38 39
Note: Includes only customers within the Planning Area
Indio Subbasin Alternative Plan Update 30 TODD/W&C
Appendix 5-A: Municipal Demand Forecast
This page intentionally blank.
APPENDIX 7-A
1997-2019 OBSERVED VS. SIMULATED GROUNDWATER ELEVATION
HYDROGRAPHS
This page intentionally left blank.
Appendix 7-A1
Groundwater Elevation
Hydrograph
03S04E14J01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
400
450
500
550
600
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
03S04E14J01S (Layer 1)
500
550
600
650
700
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
03S04E17K01S (Layer 1)
Appendix 7-A2
Groundwater Elevation
Hydrograph
03S04E17K01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
450
500
550
600
650
700
750
800
850
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation (Layer 1)
Simulated Elevation (Layer 4)
03S04E20F01S (Layer 1 and Layer 4)
Appendix 7-A3
Groundwater Elevation
Hydrograph
03S04E20F01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
300
350
400
450
500
550
600
650
700
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
03S04E29R01S (Layer 1)
Appendix 7-A4
Groundwater Elevation
Hydrograph
03S04E29R01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
300
350
400
450
500
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
03S05E30G01S (Layer 1)
Appendix 7-A5
Groundwater Elevation
Hydrograph
03S05E30G01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
100
150
200
250
300
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
04S04E13C01S (Layer 1)
Appendix 7-A6
Groundwater Elevation
Hydrograph
04S04E13C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
04S07E33L02S (Layer 2)
Appendix 7-A7
Groundwater Elevation
Hydrograph
04S07E33L02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-100
-50
0 50
100
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
05S06E15M01S (Layer 2)
Appendix 7-A8
Groundwater Elevation
Hydrograph
05S06E15M01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation (Layer 2)
Simulated Elevation (Layer 4)
06S07E23F01S (Layer 2 and Layer 4)
Appendix 7-A9
Groundwater Elevation
Hydrograph
06S07E23F01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
06S07E34D02S (Layer 2)
Appendix 7-A10
Groundwater Elevation
Hydrograph
06S07E34D02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
07S07E03D03S (Layer 2)
Appendix 7-A11
Groundwater Elevation
Hydrograph
07S07E03D03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
07S08E29P01S (Layer 2)
Appendix 7-A12
Groundwater Elevation
Hydrograph
07S08E29P01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
100
150
200
250
300
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
04S05E08R01S (Layer 4)
Appendix 7-A13
Groundwater Elevation
Hydrograph
04S05E08R01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
0 50
100
150
200
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
04S05E27E01S (Layer 4)
Appendix 7-A14
Groundwater Elevation
Hydrograph
04S05E27E01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-50
0 50
100
150
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
04S06E18Q04S (Layer 4)
Appendix 7-A15
Groundwater Elevation
Hydrograph
04S06E18Q04S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-150
-100
-50
0 50
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
05S06E10L01S (Layer 4)
Appendix 7-A16
Groundwater Elevation
Hydrograph
05S06E10L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
05S06E13D01S (Layer 4)
Appendix 7-A17
Groundwater Elevation
Hydrograph
05S06E13D01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
05S07E27L01S (Layer 4)
Appendix 7-A18
Groundwater Elevation
Hydrograph
05S07E27L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
06S07E06J01S (Layer 4)
Appendix 7-A19
Groundwater Elevation
Hydrograph
06S07E06J01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
06S07E16A02S (Layer 4)
Appendix 7-A20
Groundwater Elevation
Hydrograph
06S07E16A02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-250
-200
-150
-100
-50
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
06S08E05R03S (Layer 4)
Appendix 7-A21
Groundwater Elevation
Hydrograph
06S08E05R03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-250
-200
-150
-100
-50
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
06S08E31P01S (Layer 4)
Appendix 7-A22
Groundwater Elevation
Hydrograph
06S08E31P01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
06S08E36M01S (Layer 4)
Appendix 7-A23
Groundwater Elevation
Hydrograph
06S08E36M01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-150
-100
-50
0 1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
07S07E03A01S (Layer 4)
Appendix 7-A24
Groundwater Elevation
Hydrograph
07S07E03A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
07S09E18H01S (Layer 4)
Appendix 7-A25
Groundwater Elevation
Hydrograph
07S09E18H01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
07S09E30R02S (Layer 4)
Appendix 7-A26
Groundwater Elevation
Hydrograph
07S09E30R02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-300
-250
-200
-150
-100
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
08S08E03L01S (Layer 4)
Appendix 7-A27
Groundwater Elevation
Hydrograph
08S08E03L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-350
-300
-250
-200
-150
1996 1998 2000 2002 2004 2006 2008 2010 2012 2014 2016 2018 2020 Measured Elevation
Simulated Elevation
08S08E24A01S (Layer 4)
Appendix 7-A28
Groundwater Elevation
Hydrograph
08S08E24A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
7 _
A
p
p
e
n
d
i
x
_
A
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
APPENDIX 7-B
ADDITIONAL FUTURE PLAN SCENARIOS
This page intentionally left blank.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-1 TODD/W&C APPENDIX 7-B – ADDITIONAL FUTURE PLAN SCENARIOS
Scenarios for the Alternative Plan Update were developed based on potential future water supply conditions.
These may change as the result of land development, source substitution projects, or new water supply projects. Four categories of planning conditions were established – Baseline (No New Projects), Five-Year Plan, Future Projects, and Expanded Agriculture. For each of the four categories, one Plan scenario assumed historical hydrology and a second assumed climate change conditions. Each scenario was simulated over a 50-year period consistent with SGMA requirements. However, the planning assumptions were only projected for the first 25 years to the 2045 planning horizon. Thereafter, growth and project assumptions were assumed to continue at the same rate for the second 25 years of the simulation.
While extending beyond foreseeable land use and water resource planning projections, the second 25-year projections allow long-term evaluation of water supply and demand conditions, effectively testing Indio Subbasin sustainability under long-term hydrologic variability over 50 years.
A total of eight scenarios were analyzed during the planning process. The Baseline and four climate change scenarios are included in Chapter 7, Numerical Model and Plan Scenarios. The following description includes only the four scenarios without climate change.
1. Baseline (No New Projects): No new supply or management projects or changes to historical hydrology. This scenario is described for comparison purposes only and will never happen, because new projects are in the process of being implemented. However, a baseline is useful to assess the other scenarios.
2. Five-Year Plan: Baseline conditions plus supply and management projects included in the GSA agencies’ five-year capital improvement plans (CIPs).
3. Future Projects: Five-Year Plan conditions plus implementation of additional supply and management projects that are projected to be completed in the 25-year planning horizon.
4. Expanded Agriculture: Future Projects conditions plus expansion of agriculture resulting in increased water demands.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-2 TODD/W&C
1. BASELINE (NO NEW PROJECTS)
The Baseline scenario includes only those supplies and facilities currently in place to support Indio Subbasin management and assumes that no new projects or water supplies will be implemented. The Baseline propagates current conditions into the future to use as a basis for comparing ‘with and without’ future project conditions. Figure 1 provides a flow chart that shows the water balance (inflows and outflows) of the Subbasin under Baseline assumptions, as well as the supplies used to meet demands. Table 1 provides a summary of Baseline supplies used to directly meet demand and Table 2 provides a summary of supplies used for replenishment. Supply inputs used for the model (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, and watershed runoff) and groundwater pumping are derived from the MODFLOW model. A summary of the assumptions for each supply source is provided below.
The Baseline scenario assumes passive conservation savings, surface water diversions, and GRF operations will continue to be implemented, along with potable water and sewer consolidations.
Table 1. Baseline (No New Projects) Scenario – Modeled Deliveries for Direct Use (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Groundwatera 296,089 308,643 321,483 334,169 344,092 353,244 Colorado Riverb 285,337 284,818 282,419 280,771 279,370 277,969 Recycled Water 13,397 13,397 13,397 13,397 13,397 13,397 Total Direct Use Supplies 594,823 606,858 617,299 628,337 636,859 644,610 a Simulated groundwater pumping in the model scenarios is within 0.03 percent; the slight difference is due to the differences in model area vs. Subbasin extent and numerical precision.
b Colorado River deliveries decrease over time due to conversion of agriculture that receives Canal deliveries to urban uses.
Table 2. Baseline (No New Projects) Scenario – Modeled Deliveries for Replenishment (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Colorado Rivera 97,000 97,000 82,000 82,000 82,000 82,000 SWP Exchangeb 60,527 60,297 60,092 59,903 79,724 79,431 Other: Rosedale Rio-Bravo 10,563 10,563 10,563 10,563 0 0 Surface Water Diversionsc 2,630 6,000 6,000 6,000 6,000 6,000 Total Replenishment 170,720 173,860 158,655 158,466 167,724 167,431 Note: Groundwater inflows and outflows (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, watershed runoff) are described in Section 7.6.
a Colorado River volumes assume that 15,000 AFY MWD-SWP transfer ends in 2027. b SWP Exchange volumes assume Advanced Delivery credit from 2002 to 2035. This assumption is used so as not to double count advanced deliveries in future SWP deliveries.
c Surface water diversion include a small fraction of direct deliveries; for simplicity, all diversion volumes are assumed herein to be directed to WWR-GRF for recovery.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-3 TODD/W&C Figure 1: Baseline (No New Projects) Supply and Demand Flow Chart, 2045 Note: Values in this graphic are rounded to the nearest hundred and may not sum to totals. Colorado River volumes do not sum to total due to underrun under Baseline scenario with no new projects
assumption.
Local Inflows, Outflows, and Supplies: As illustrated in Figure 1, inflows to groundwater include subsurface inflow, mountain front recharge, surface water runoff that is diverted for replenishment or percolates along the mountain front or in local channels (minus losses to the Salton Sea), wastewater percolation, and return flows from use (which include septic system percolation). Total surface water runoff from local watersheds is estimated based on the 50-year hydrologic period from 1970 to 2019 and simulated into the future using the MODFLOW model. Runoff inflows are assumed to vary annually, with estimated natural infiltration of watershed runoff (minus diversions and outflows to the Salton Sea) am ounting to an annual average of 43,319 AF for the 50-year hydrologic period. Septic system inflow starts at 8,800 AFY in 2020 and decreases to 4,600 AFY by 2045 due to the connection of septic systems to sewers. Wastewater percolation serves as an inflow to the Subbasin and occurs at five wastewater treatment facility sites (Palm Springs WWTP, CVWD WRP-2, CVWD WRP-7, CVWD WRP-10, and MSWD Regional WRF). Wastewater percolation is assumed to provide an average Subbasin inflow of 6,316 AFY in 2020 and ramping up to 18,377 AFY by 2045. Return flows from municipal, agricultural, and golf course demands are based on estimates of outdoor water use.
Outflows from the Indio Subbasin include drain flow, evapotranspiration, and subsurface outflow. Subsurface inflow, drain flow, evapotranspiration, and subsurface outflow are derived from the MODFLOW model.
As shown in Table 2, local supplies used for replenishment include surface water diversions. Under Baseline, local surface water diversions increase to 6,000 AFY by 2023, all of which is diverted to WWR-GRF subsurface storage and then recovered for delivery.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-4 TODD/W&C Colorado River: Colorado River water supplies available under Baseline include CVWD’s base entitlement under the 2003 Quantification Settlement Agreement, along with transfers where there are agreements in place. Baseline assumes that diversions under the QSA ramp up from 394,000 AFY in 2020 to 424,000 AFY between 2027 and 2045 in 5,000 AFY increments. This ramp-up will allow the CVWD to fully utilize available Colorado River water at its maximum entitlement. The Colorado River supplies used in Baseline include a 15,000 AFY transfer from Metropolitan Water District of Southern California (MWD) delivered to WWR-GRF (MWD retains the remaining 5,000 AFY) and 35,000 AFY of SWP transfer with MWD per the 2003 QSA.
Baseline also assumes annual Canal conveyance losses of 5 percent. Under the Baseline scenario, a portion of available Colorado River supply is not able to be beneficially used without the construction of new projects.
Colorado River supplies are assumed to be used for replenishment and direct use, as follows:
• Colorado River replenishment:
o TEL-GRF: Recharge limited to current recharge of 37,000 AFY o PD-GRF: Recharge limited to Phase I capacity of 10,000 AFY o WWR-GRF: Recharge of 15,000 AFY of MWD transfer from 2020 to 2026 (totaling 105,000 AF) and recharge of 35,000 AFY of QSA MWD transfer through the planning horizon. • Colorado River direct deliveries: Delivery to current agricultural, East Valley golf courses, other recreation, WRP-7, WRP-10, and MVP direct users at current levels equaling 278,000 AFY, less reduced agricultural demands due to urban conversion.
SWP Exchange: Average annual SWP Exchange supplies under Baseline are based on the reliability of SWP deliveries received by CVWD and DWA since 2007 when Federal Judge Wanger overturned the Biological Opinion authored by USFWS and USBR concerning Delta export pumping operations. This decision significantly impacted DWR’s ability to convey SWP supplies across the Delta for export. Baseline applies an average 45 percent reliability to SWP deliveries.
Additionally, MWD’s Advance Delivery account had 353,946 AF in storage as of January 2020. Baseline assumes that MWD will credit SWP deliveries against the Advance Delivery account at 22,122 AF annually from 2020-2035 so as not to double count these deliveries. Additional SWP Exchange water is available through Yuba Accord deliveries and is assumed to have a 10-year average of 651 AFY.
SWP Exchange supplies modeled under Baseline are varied annually based on the historical variability of SWP Table A deliveries received by the CVWD and DWA. Final SWP allocations between 2007 and 2021 have ranged from a high of 85 percent in 2017 to a low of 5 percent in 2014 and again in 2021. Baseline applies an annual variability factor that mimics the variability of deliveries associated with different climate years. The variability factors were developed based on the same water years (1970 to 2019) as local hydrology.
SWP Exchange water is assumed to be used for replenishment at WWR-GRF and MC-GRF, and the split of water between these replenishment facilities is to be consistent with the 2004 Settlement Agreement between DWA, CVWD, and MSWD.
Other Supplies: One additional supply is included under Baseline: Rosedale-Rio Bravo deliveries of 10,563 AFY from 2020 to 2035.
Recycled Water: Recycled water supplies are currently produced at three locations: Palm Springs WWTP/DWA WRP, CVWD WRP-7, and CVWD WRP-10. Recycled water supply availability is expected to
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-5 TODD/W&C increase due to an increase in indoor water use and associated wastewater flows within the Plan area. Total recycled water use is expected to remain at 13,397 AFY as no new projects or non-potable connections are assumed to be implemented under Baseline.
2. FIVE-YEAR PLAN
The Five-Year Plan scenario includes supplies and facilities currently in place to support Subbasin management, along with new projects or supplies under the control of GSAs that are planned to be completed as part of the GSAs’ five-year capital improvement programs (5-year CIPs). Table 5 provides a summary of Five-Year Plan with Climate Change supplies used to directly meet demand and Table 6 provides a summary of supplies used for replenishment and percolation to the Subbasin. Supply inputs used for the model (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, and watershed runoff) and groundwater pumping are derived from the MODFLOW model. Figure 3 provides a flow chart that shows the water balance of the basin under Five-Year Plan with Climate Change, as well as the supplies used to meet demands. A summary of the assumptions applied to each supply source is provided below.
The Five-Year Plan scenario assumes passive conservation, surface water diversions, and GRF operations will continue to be implemented, along with potable water and sewer consolidations. Planned non-potable expansions from WRP-7 and WRP-10 will deliver Canal and recycled water, along with Canal deliveries to East Valley golf courses and the Oasis Distribution System. Additionally, PD-GRF expansion will allow for greater Subbasin replenishment.
Table 3. Five Year Plan Scenario – Modeled Deliveries for Direct Use (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Groundwater Pumpinga 296,089 271,914 284,754 297,440 307,362 316,514 Colorado Riverb 285,337 317,932 314,733 312,385 310,184 307,883 Recycled Water 13,397 17,013 17,813 18,513 19,313 20,213 Total Direct Use Supplies 594,823 606,858 617,299 628,337 636,859 644,610 a Simulated groundwater pumping in the model scenarios is within 0.03 percent; the slight difference is due to the differences in model area vs. Subbasin extent and numerical precision.
b Colorado River deliveries increase over time due to new non-potable connections.
Table 4. Five Year Plan – Modeled Deliveries Used for Replenishment (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Colorado Rivera 97,000 108,368 97,000 97,000 97,000 97,000 SWP Exchangeb 60,527 62,816 62,603 62,405 82,217 81,915 Other: Rosedale Rio-Bravo 10,563 10,563 10,563 10,563 0 0 Surface Water Diversionsc 2,630 6,000 6,000 6,000 6,000 6,000 Total Replenishment 170,720 187,747 176,166 175,968 185,217 184,915 Note: Groundwater inflows and outflows (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, watershed runoff) are described in Section 7.6.
a Colorado River volumes assume that 15,000 AFY MWD-SWP transfer ends in 2027. b SWP Exchange volumes assume Advanced Delivery credit from 2002 to 2035. This assumption is used so as not to double count advanced deliveries in future SWP deliveries.
c Surface water diversion include a small fraction of direct deliveries; for simplicity, all diversion volumes are assumed herein to be directed to WWR-GRF for recovery.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-6 TODD/W&C
Figure 2: Five Year Plan Supply and Demand Flow Chart, 2045 Note: Values in this graphic are rounded to the nearest hundred and may not sum to totals.
Local Inflows, Outflows, and Supplies: Surface water hydrology under Five-Year Plan are the same as Baseline as are return flows and septic system inflow. Wastewater percolation is expected to be reduced due to an increase in recycled water use. Subsurface inflow, drain flow, evapotranspiration, and subsurface outflow are derived from the MODFLOW model.
Colorado River: Colorado River water supplies available under the Five-Year Plan are assumed to remain the same as under Baseline; however, available supplies will be routed differently due to planned expansions to replenishment facilities and direct deliveries. Under Five-Year Plan, the PD-GRF is planned to expand to allow for recharge to increase from 10,000 AFY in 2020 to 25,000 AFY in 2023. Combined replenishment at WWR-GRF, TEL-GRF, and PD-GRF is stable at 97,000 AFY through 2045. Increases in Colorado River direct deliveries begin in 2022 and total 29,914 AFY by 2045.
SWP Exchange: SWP Exchange supplies available under the Five-Year Plan are the same as under Baseline. SWP Exchange water is assumed to be used for replenishment at the WWR-GRF and MC-GRF, consistent with the 2004 Settlement Agreement.
Recycled Water: Recycled water availability is expected to increase recycled water production and deliveries to new non-potable connections. WRP-7 deliveries increase from 2,201 AFY in 2020 to 2,800 AFY in 2025. WRP-10 deliveries increase from 7,783 AFY in 2020 to 14,000 AFY in 2045.
Other Supplies: Rosedale-Rio Bravo deliveries remain the same as in Baseline.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-7 TODD/W&C
3. FUTURE PROJECTS
The Future Projects Scenario (Future Projects) includes supplies and facilities currently in place to support Subbasin management, along with projects for new supplies and facilities that are planned by the GSA agencies within the 25-year planning horizon. Table 9 provides a summary of Future Projects supplies used to directly meet demand and supplies used for replenishment and Table 10 provides a summary of supplies used for replenishment and percolation to the Subbasin. Supply inputs used for the model (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, and watershed runoff) and groundwater pumping are derived from the MODFLOW model. Figure 5 provides a flow chart that shows the water balance of the Subbasin under Future Projects, as well as the supplies used to meet demands. A summary of the assumptions applied to each supply source is provided below.
The Future Projects scenario assumes passive conservation, surface water diversions, and GRF operations will continue to be implemented, along with potable water and sewer consolidations. Planned non-potable expansions from WRP-7 and WRP-10 will deliver increased Canal and recycled water, along with increased Canal deliveries to Mid-Valley Pipeline connections, East Valley golf courses, and the Oasis Distribution System (as compared to the Five-Year Plan scenario). The EVRA potable reuse project will be implemented.
Table 5. Future Projects Scenario – Modeled Deliveries for Direct Use (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Groundwater Pumpinga 296,088 271,914 266,364 261,423 267,252 276,404 Colorado Riverb 285,337 317,932 333,122 348,401 350,294 347,993 Recycled Water 13,397 17,013 17,813 18,513 19,313 20,213 Total Direct Use Supplies 594,823 606,858 617,299 628,337 636,859 644,610 a Simulated groundwater pumping in the model scenarios is within 0.03 percent; the slight difference is due to the differences in model area vs. Subbasin extent and numerical precision.
b Colorado River deliveries increase over time due to new non-potable connections.
Table 6. Future Projects Scenario – Modeled Deliveries Used for Replenishment (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Colorado Rivera 97,000 108,368 100,000 87,649 85,756 88,057 SWP Exchangeb 60,527 62,816 62,603 72,908 92,682 116,262 Other: Rosedale Rio-Bravo 10,563 10,563 10,563 10,563 0 0 Indirect Potable Reuse 0 0 5,000 5,000 5,000 5,000
Surface Water Diversionsc 2,630 6,000 6,000 6,000 6,000 6,000 Total Replenishment 170,720 187,747 184,166 182,120 189,438 215,319 Note: Groundwater inflows and outflows (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, watershed runoff) are described in Section 7.6.
a Colorado River volumes assume that 15,000 AFY MWD-SWP transfer ends in 2027. b SWP Exchange volumes assume Advanced Delivery credit from 2002 to 2035. This assumption is used so as not to double count advanced deliveries in future SWP deliveries. SWP Exchange includes future supplies from DCF, Sites Reservoir, and Lake Perris Seepage. c Surface water diversion include a small fraction of direct deliveries; for simplicity, all diversion volumes are assumed herein to be directed to WWR-GRF for recovery.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-8 TODD/W&C Figure 3: Future Projects Supply and Demand Flow Chart, 2045 Note: Values in this graphic are rounded to the nearest hundred and may not sum to totals.
Local Inflows, Outflows, and Supplies: Surface water hydrology under Future Projects is the same as Baseline, as are return flows and septic system inflows. Wastewater percolation is expected to be reduced due to an increase in recycled water use, along with the transfer of MSWD Regional WRF flows to the Mission Creek Subbasin. Subsurface inflow, drain flow, evapotranspiration, and subsurface outflow are derived from the MODFLOW model.
Colorado River: Colorado River water supplies available under Future Projects are assumed to remain the same as under the Five-Year Plan scenario, but with additional expansions to replenishment facilities and direct deliveries. Under Future Projects, the TEL-GRF will expand from a capacity of 37,000 AFY in 2020 to 40,000 AFY in 2025. Increases in Colorado River direct deliveries begin in 2022 and total 70,024 AFY by 2045. As available Colorado River supply is fully utilized in the Mid- and East Valley, CVWD will reduce replenishment at the WWR-GRF. The increase in direct deliveries results in a reduction in replenishment of CVWD’s 2003 QSA entitlement at WWR-GRF beginning in 2025 to a low of 20,756 AFY in 2040.
SWP Exchange: SWP Exchange supplies available under Future Projects include the Table A deliveries (45 percent average reliability and varied annually based on water year) assumed under Baseline, with the addition of the following projects:
• Delta Conveyance Facility (DCF) to increase the reliability of SWP deliveries by 26,500 AFY (59% of Table A) due to improvements in Delta conveyance; deliveries will vary according to the same variability factors used for SWP Table A water under Baseline and used for replenishment at WWR- GRF and MC-GRF.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-9 TODD/W&C • Lake Perris Dam Seepage Recovery Project to provide 2,754 AFY from 2025 to 2045 and used for replenishment at WWR-GRF and MC-GRF.
• Sites Reservoir Project to provide 11,550 AFY from 2035 to 2045 and used for replenishment at the WWR-GRF; 30 percent conveyance loss will be applied to this supply.
Recycled Water: Recycled water supplies under Future Projects are further expanded from those shown under the Five-Year Plan, including an increase in recycled water deliveries by 6,815 AFY in 2045 and with 5,000 AFY of potable reuse from Valley Sanitary District’s WRP (referred to as the EVRA Potable Reuse Project).
Other Supplies: Rosedale-Rio Bravo deliveries remain the same as in Baseline.
4. EXPANDED AGRICULTURE
The Expanded Agriculture Scenario (Expanded Agriculture) includes increased agricultural demands, along with the same suite of planned future projects described under the Future Projects Scenario. This scenario assumes 8,000 acres of additional farmland (inclusive of 1,500 AFY in baseline demand forecast). Most Oasis farmlands are currently served by groundwater. This scenario assumes that new agricultural growth occurs due to expanded availability of Canal water to come currently idle lands. The scenario allocates 85 percent of new demands to Canal water and 15 percent to groundwater.
Table 13 provides a summary of Expanded Agriculture supplies used to directly meet demand and Table 14 provides a summary of supplies used for replenishment and percolation to the Subbasin. Supply inputs used for the model (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, and watershed runoff) and groundwater pumping are derived from the MODFLOW model. Figure 7 provides a flow chart that shows the water balance of the Indio Subbasin under Expanded Agriculture, as well as the supplies used to meet demands.
The Expanded Agriculture scenario assumes the same supplies as the Future Projects scenario – continued passive conservation, surface water diversions, and GRF operations, along with potable water and sewer consolidations. Planned non-potable expansions from WRP-7 and WRP-10 will deliver increased Canal and recycled water, along with increased Canal deliveries to Mid-Valley Pipeline connections, East Valley golf courses, and the Oasis Distribution System. The EVRA potable reuse project will be implemented.
Table 7. Expanded Agriculture Scenario – Modeled Deliveries for Direct Use (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Groundwater Pumping a 296,088 272,967 268,470 264,581 271,463 281,667 Colorado Riverb 285,337 323,896 345,051 366,295 374,152 377,816 Recycled Water 13,397 17,013 17,813 18,513 19,313 20,213 Total Direct Use Supplies 594,823 613,876 631,334 649,389 664,928 679,696 a Simulated groundwater pumping in the model scenarios is within 0.03 percent; the slight difference is due to the differences in model area vs. Subbasin extent and numerical precision.
b Colorado River deliveries increase over time due to new non-potable connections.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-10 TODD/W&C Table 8. Expanded Agriculture Scenario – Modeled Deliveries for Replenishment (AFY) Supply (Acre-Feet) 2020 2025 2030 2035 2040 2045
Colorado Rivera 97,000 102,404 90,999 69,755 61,898 58,234 SWP Exchangeb 60,527 62,816 62,603 72,908 92,682 116,262 Other: Rosedale Rio-Bravo 10,563 10,563 10,563 10,563 0 0 Potable Reuse 0 0 5,000 5,000 5,000 5,000
Surface Water Diversionsc 2,630 6,000 6,000 6,000 6,000 6,000 Total Replenishment 170,720 181,783 175,165 164,226 165,580 185,496 Note: Groundwater inflows and outflows (septic systems, return flows, subsurface inflow and outflow, drain flows, evapotranspiration, watershed runoff) are described in Section 7.6.
a Colorado River volumes assume that 15,000 AFY MWD-SWP transfer ends in 2027. b SWP Exchange volumes assume Advanced Delivery credit from 2002 to 2035. This assumption is used so as not to double count advanced deliveries in future SWP deliveries. SWP Exchange includes future supplies from DCF, Sites Reservoir, and Lake Perris Seepage. c Surface water diversion include a small fraction of direct deliveries; for simplicity, all diversion volumes are assumed herein to be directed to WWR-GRF for recovery.
Figure 4: Expanded Agriculture with Future Projects Supply and Demand Flow Chart, 2045 Note: Values in this graphic are rounded to the nearest hundred and may not sum to totals.
Local Inflows, Outflows, and Supplies: Surface water hydrology under Expanded Agriculture is the same as Baseline, as are return flows and septic system inflows. Wastewater percolation is expected to be reduced due to an increase in recycled water use. Subsurface inflow, drain flow, evapotranspiration, and subsurface outflow are derived from the MODFLOW model.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-11 TODD/W&C Colorado River: Colorado River water supplies available under Expanded Agriculture are assumed to remain the same as under the Future Projects, but with additional direct deliveries to the expanded agricultural areas. Replenishment facility expansions will be the same as in Future Projects. Increases in Colorado River direct deliveries begin in 2021 and total 99,800 AFY by 2045. As available Colorado River supply is fully utilized in the Mid- and East Valley, CVWD will reduce replenishment at the GRFs. This results in a reduction in replenishment of Colorado River water at PD-GRF beginning in 2038 to a low of 18,967 AFY, along with ending QSA deliveries at WWR-GRF in 2037.
SWP Exchange: SWP Exchange supplies are the same as under Future Projects and include Table A deliveries (45 percent average reliability and varied annually based on water year) along with DCF, Lake Perris Dam Seepage Recovery Project, and Sites Reservoir Project.
Recycled Water: Recycled water supplies are the same as under Future Projects.
Other Supplies: Rosedale-Rio Bravo deliveries remain the same as in Baseline.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-12 TODD/W&C
This page intentionally left blank.
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-13 TODD/W&C Table 9. Assumptions in Plan Scenarios
1- Baseline (No Project) 2- Baseline (No Project) w/
Climate Change
3- 5-Year Plan 4- Five-Year Plan w/Climate
Change
5- Future Projects 6- Future Projects w/Climate
Change
7- Expanded Agriculture 8- Expanded Agriculture
w/Climate Change
Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water Surface Water • Watershed runoff
(streamflow, subsurface
inflow, ET) based on 50-yr
average minus average
losses to Salton Sea and
diversions
• Watershed runoff
(streamflow, subsurface
inflow, ET) based on 25-yr
dry cycle minus average
losses to Salton Sea and
diversions
• Watershed runoff
(streamflow, subsurface
inflow, ET) based on 50-yr
average minus average
losses to Salton Sea and
diversions
• Watershed runoff
(streamflow, subsurface
inflow, ET) based on 25-yr
dry cycle minus average
losses to Salton Sea and
diversions
• Watershed runoff
(streamflow, subsurface
inflow, ET) based on 50-yr
average minus average
losses to Salton Sea and
diversions
• Watershed runoff
(streamflow, subsurface
inflow, ET) based on 25-yr
dry cycle minus average
losses to Salton Sea and
diversions
• Watershed runoff
(streamflow, subsurface
inflow, ET) based on 50-yr
average minus average
losses to Salton Sea and
diversions
• Watershed runoff
(streamflow, subsurface
inflow, ET) based on 25-yr
dry cycle minus average
losses to Salton Sea and
diversions
• Surface water diversions
increase in 2023-2045
• Surface water diversions
increase in 2023-2045
• Surface water diversions
increase in 2023-2045
• Surface water diversions
increase in 2023-2045
• Surface water diversions
increase in 2023-2045
• Surface water diversions
increase in 2023-2045
• Surface water diversions
increase in 2023-2045
• Surface water diversions
increase in 2023-2045
Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment • Recharge of assumed
natural infiltration in West
AOB
• Recharge of assumed
natural infiltration in West
AOB
• Recharge of assumed
natural infiltration in West
AOB
• Recharge of assumed
natural infiltration in West
AOB
• Recharge of assumed
natural infiltration in West
AOB
• Recharge of assumed
natural infiltration in West
AOB
• Recharge of assumed
natural infiltration in West
AOB
• Recharge of assumed
natural infiltration in West
AOB
Colorado River Colorado River Colorado River Colorado River Colorado River Colorado River Colorado River Colorado River • QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• QSA ramps up to 424,000
AFY in 2027-2045. Ramp up
in 5,000 AFY increments
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Addition of QSA MWD SWP
Transfer, with loss of 5,000
AFY to MWD per 2019
Amendment
• Canal conveyance losses of
5% annually
• Canal conveyance losses of
5% annually
• Canal conveyance losses of
5% annually
• Canal conveyance losses of
5% annually
• Canal conveyance losses of
5% annually
• Canal conveyance losses of
5% annually
• Canal conveyance losses of
5% annually
• Canal conveyance losses of
5% annually
• Under Lower Basin DCP,
assume delivery reduction of
CVWD’s 7% of CA
contribution
• Under Lower Basin DCP,
assume delivery reduction of
CVWD’s 7% of CA
contribution
• Under Lower Basin DCP,
assume delivery reduction of
CVWD’s 7% of CA
contribution
• Under Lower Basin DCP,
assume delivery reduction of
CVWD’s 7% of CA
contribution
Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment • Recharge to TEL-GRF
based on current capacity
• Recharge to TEL-GRF
based on current capacity
• Recharge to TEL-GRF
based on current capacity
• Recharge to TEL-GRF
based on current capacity
• Recharge to TEL-GRF
expands to 40,000 AF in
2025-2045
• Recharge to TEL-GRF
expands to 40,000 AF in
2025-2045
• Recharge to TEL-GRF
expands to 40,000 AF in
2025-2045
• Recharge to TEL-GRF
expands to 40,000 AF in
2025-2045
• Recharge to PD-GRF based
on Phase I capacity
• Recharge to PD-GRF based
on Phase I capacity
• Recharge to PD-GRF
expands to 25,000 AFY in
2023
• Recharge to PD-GRF
expands to 25,000 AFY in
2023
• Recharge to PD-GRF
expands to 25,000 AFY in
2023
• Recharge to PD-GRF
expands to 25,000 AFY in
2023
• Recharge to PD-GRF
expands to 25,000 AFY in
2023
• Recharge to PD-GRF
expands to 25,000 AFY in
2023
• Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
• Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
• Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
• Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
• Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
Delivery of MWD/IID
Transfer at WWR-GRF from
2020-2026
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
• Delivery of QSA MWD SWP
Transfer to WWR-GRF
through 2045
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-14 TODD/W&C 1- Baseline (No Project) 2- Baseline (No Project) w/ Climate Change 3- 5-Year Plan 4- Five-Year Plan w/Climate Change 5- Future Projects 6- Future Projects w/Climate Change 7- Expanded Agriculture 8- Expanded Agriculture w/Climate Change Direct Deliveries Direct Deliveries Direct Deliveries Direct Deliveries Direct Deliveries Direct Deliveries Direct Deliveries Direct Deliveries • Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• Current Ag, East Valley Golf,
West Valley/MVP Golf, Other
Rec, WRP-10, and MVP
Direct at current levels,
minus conversion of some
farmland to urban uses
• New Canal deliveries per
NPW forecast
• New Canal deliveries per
NPW forecast
• New Canal deliveries per
NPW forecast
• New Canal deliveries per
NPW forecast
• New Canal deliveries per
NPW forecast
• New Canal deliveries per
NPW forecast
• Additional Canal direct
deliveries per expanded Ag
forecast
• Additional Canal direct
deliveries per expanded Ag
forecast
SWP Exchange Water SWP Exchange Water SWP Exchange Water SWP Exchange Water SWP Exchange Water SWP Exchange Water SWP Exchange Water SWP Exchange Water • Table A delivery at avg 45%
reliability, delivered per
MC/WWR split). Variable
annually per historical SWP
final allocation.
• Table A delivery at avg 45%
reliability minus -1.5%
climate change factor by
2045, delivered per
MC/WWR split). Variable
annually per historical SWP
final allocation.
• Table A delivery at avg 45%
reliability, delivered per
MC/WWR split). Variable
annually per historical SWP
final allocation.
• Table A delivery at avg 45%
reliability minus -1.5%
climate change factor by
2045, delivered per
MC/WWR split). Variable
annually per historical SWP
final allocation.
• Table A delivery at avg 45%
reliability, delivered per
MC/WWR split). Variable
annually per historical SWP
final allocation.
• Table A delivery at avg 45%
reliability minus -1.5% climate
change factor by 2045,
delivered per MC/WWR split).
Variable annually per historical
SWP final allocation.
• Table A delivery at avg 45%
reliability, delivered per
MC/WWR split). Variable
annually per historical SWP
final allocation.
• Table A delivery at avg 45%
reliability minus -1.5% climate
change factor by 2045,
delivered per MC/WWR split).
Variable annually per historical
SWP final allocation.
• Allocation of Table A
between WWR-GRF and
MC-GRF consistent w/2004
Settlement Agreement
• Allocation of Table A
between WWR-GRF and
MC-GRF consistent w/2004
Settlement Agreement
• Allocation of Table A
between WWR-GRF and
MC-GRF consistent w/2004
Settlement Agreement
• Allocation of Table A
between WWR-GRF and
MC-GRF consistent w/2004
Settlement Agreement
• Allocation of Table A
between WWR-GRF and
MC-GRF consistent w/2004
Settlement Agreement
• Allocation of Table A between
WWR-GRF and MC-GRF
consistent w/2004 Settlement
Agreement
• Allocation of Table A between
WWR-GRF and MC-GRF
consistent w/2004 Settlement
Agreement
• Allocation of Table A between
WWR-GRF and MC-GRF
consistent w/2004 Settlement
Agreement
• Yuba Accord deliveries at
10-year average
• Yuba Accord deliveries at
10-year average
• Yuba Accord deliveries at
10-year average
• Yuba Accord deliveries at
10-year average
• Yuba Accord deliveries at
10-year average
• Yuba Accord deliveries at 10-
year average
• Yuba Accord deliveries at 10-
year average
• Yuba Accord deliveries at 10-
year average
• Lake Perris Seepage per
2019 Term Sheet (per
MC/WWR Split)
• Lake Perris Seepage per
2019 Term Sheet (per
MC/WWR Split)
• Lake Perris Seepage per
2019 Term Sheet (per
MC/WWR Split)
• Lake Perris Seepage per 2019
Term Sheet (per MC/WWR
Split)
• Lake Perris Seepage per 2019
Term Sheet (per MC/WWR
Split)
• Lake Perris Seepage per 2019
Term Sheet (per MC/WWR
Split)
• Sites Reservoir deliveries at
participation amount (with
30% conveyance loss)
beginning in 2035
• Sites Reservoir deliveries at
participation amount (with
30% conveyance loss)
beginning in 2035
• Sites Reservoir deliveries at
participation amount (with
30% conveyance loss)
beginning in 2035
• Sites Reservoir deliveries at
participation amount (with
30% conveyance loss)
beginning in 2035
• Once DCF is constructed,
increase in SWP reliability
up to 59% annually
• Once DCF is constructed,
increase in SWP reliability
up to 59% annually minus -
1.5% climate change factor
by 2045
• Once DCF is constructed,
increase in SWP reliability
up to 59% annually
• Once DCF is constructed,
increase in SWP reliability
up to 59% annually minus -
1.5% climate change factor
by 2045
Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment • Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
• Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
• Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
• Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
• Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
• Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
• Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
• Recharge to WWR-GRF
based on SWP allocation
and 2004 Agreement
Recycled Water Recycled Water Recycled Water Recycled Water Recycled Water Recycled Water Recycled Water Recycled Water • DWA WRF to deliver
recycled water based on
average 2015-2019
• DWA WRF to deliver
recycled water based on
average 2015-2019
• DWA WRF to deliver
recycled water based on
average 2015-2019
• DWA WRF to deliver
recycled water based on
average 2015-2019
• DWA WRF to deliver
recycled water based on
average 2015-2019
• DWA WRF to deliver
recycled water based on
average 2015-2019
• DWA WRF to deliver
recycled water based on
average 2015-2019
• DWA WRF to deliver
recycled water based on
average 2015-2019
• CVWD WRP-7 to deliver
recycled water to golf and
municipal based on average
2015-2019
• CVWD WRP-7 to deliver
recycled water to golf and
municipal based on average
2015-2019
• CVWD WRP-7 to increase
deliveries consistent w/NPW
forecast per West/MVP
connections
• CVWD WRP-7 to increase
deliveries consistent w/NPW
forecast per West/MVP
connections
• CVWD WRP-7 to increase
deliveries consistent w/NPW
forecast per West/MVP
connections
• CVWD WRP-7 to increase
deliveries consistent w/NPW
forecast per West/MVP
connections
• CVWD WRP-7 to increase
deliveries consistent w/NPW
forecast per West/MVP
connections
• CVWD WRP-7 to increase
deliveries consistent w/NPW
forecast per West/MVP
connections
Appendix 7-B: Additional Future Plan Scenarios DRAFT
Indio Subbasin Water Management Plan Update 7B-15 TODD/W&C 1- Baseline (No Project) 2- Baseline (No Project) w/ Climate Change 3- 5-Year Plan 4- Five-Year Plan w/Climate Change 5- Future Projects 6- Future Projects w/Climate Change 7- Expanded Agriculture 8- Expanded Agriculture w/Climate Change • CVWD WRP-10 to deliver
recycled water to golf and
municipal based on average
2018-2019
• CVWD WRP-10 to deliver
recycled water to golf and
municipal based on average
2018-2019
• CVWD WRP-10 to increase
deliveries consistent w/NPW
forecast
• CVWD WRP-10 to increase
deliveries consistent w/NPW
forecast
• CVWD WRP-10 to increase
deliveries consistent w/NPW
forecast
• CVWD WRP-10 to increase
deliveries consistent w/NPW
forecast
• CVWD WRP-10 to increase
deliveries consistent w/NPW
forecast
• CVWD WRP-10 to increase
deliveries consistent w/NPW
forecast
Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment Replenishment • Wastewater percolation per
WW flows minus projected
recycled water deliveries
• Wastewater percolation per
WW flows minus projected
recycled water deliveries
• Wastewater percolation per
WW flows minus projected
recycled water deliveries
• Wastewater percolation per
WW flows minus projected
recycled water deliveries
• Wastewater percolation per
WW flows minus projected
recycled water deliveries
• Wastewater percolation per
WW flows minus projected
recycled water deliveries
• Wastewater percolation per
WW flows minus projected
recycled water deliveries
• Wastewater percolation per
WW flows minus projected
recycled water deliveries
• EVRA IPR Project (using
VSD WWTP) begins potable
replenishment in 2030-2045
• EVRA IPR Project (using
VSD WWTP) begins potable
replenishment in 2030-2045
• EVRA IPR Project (using
VSD WWTP) begins potable
replenishment in 2030-2045
• EVRA IPR Project (using
VSD WWTP) begins potable
replenishment in 2030-2045
Other Supplies Other Supplies Other Supplies Other Supplies Other Supplies Other Supplies Other Supplies Other Supplies • Rosedale Rio-Bravo
deliveries 2020-2035
• Rosedale Rio-Bravo
deliveries 2020-2035
• Rosedale Rio-Bravo
deliveries 2020-2035
• Rosedale Rio-Bravo
deliveries 2020-2035
• Rosedale Rio-Bravo
deliveries 2020-2035
• Rosedale Rio-Bravo
deliveries 2020-2035
• Rosedale Rio-Bravo
deliveries 2020-2035
• Rosedale Rio-Bravo
deliveries 2020-2035
Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater Groundwater • Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
• Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
• Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
• Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
• Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
• Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
• Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
• Net return flow = municipal +
agricultural + golf return flow,
minus estimated subsurface
outflows, ET, and drain flows
Conservation Conservation Conservation Conservation Conservation Conservation Conservation Conservation • Passive municipal
conservation
• Passive municipal
conservation
• Passive municipal
conservation
• Passive municipal
conservation
• Passive municipal
conservation
• Passive municipal
conservation
• Passive municipal
conservation
• Passive municipal
conservation
This page intentionally left blank.
APPENDIX 7-C
ADDITIONAL FUTURE SCENARIO WATER BUDGETS AND MODEL SIMULATIONS
This page intentionally left blank.
Indio Subbasin C-1
Numerical Model and Plan Scenarios TODD / W&C
Appendix 7-C Additional Future Scenario Water Budgets and Model Simulations As documented in Chapter 7, scenarios for the Alternative Plan were developed based on potential future water supply conditions. These may change as the result of land development, source substitution projects, or new water supply projects. Four categories of planning conditions were established – Baseline (No New Projects), Five-Year Plan, Future Projects, and Expanded Agriculture. For each of the four categories, one Plan scenario assumed historical hydrology and a second assumed climate change conditions. Each scenario was simulated over a 50-year period consistent with SGMA requirements. However, the planning assumptions were only projected for the first 25 years to the 2045 planning horizon. Thereafter, growth and project assumptions were assumed to continue at the same rate for the second 25 years of the simulation.
While extending beyond foreseeable land use and water resource planning projections, the second 25-year projections allow long-term evaluation of water supply and demand conditions, effectively testing Indio Subbasin sustainability under long-term hydrologic variability over 50 years.
The same suite of projects simulated in the scenarios described in Chapter 7 were also simulated without Climate Change. These scenarios were simulated using future hydrological conditions based on the past 50 years of observed hydrological data, in contrast to the climate change simulations of the past 25 years of observed hydrological data. The results of those simulations, without climate change, are included here.
The following scenario simulations are shown here:
1.Baseline (No Project): No new supply projects or changes to historical hydrology.
2.Five-Year Plan: Baseline conditions plus supply projects included in the GSA agencies’ five-year capital improvement plans (CIPs), without anticipated climate change hydrology.
3.Future Projects: Five-Year Plan conditions plus implementation of additional supplies and facilities that are in the planning phases by GSA agencies, subsequent phases of projects, and/or GSAs are participating agencies, along without anticipated climate change hydrology.
4.Expanded Agriculture plus Future Projects: Future Projects conditions plus significant increases in agriculture resulting in increased agricultural demand, along without anticipated climate change hydrology.
Indio Subbasin C-2
Numerical Model and Plan Scenarios TODD / W&C
The results are shown in the following figures:
Figure 7-C1 Annual Model Water Budget for Additional Scenarios Figure 7-C2 Cumulative Change in Storage for Additional Scenarios Figure 7-C3 Total Model Inflow for Additional Scenarios Figure 7-C4 Simulated Pumping for Additional Scenarios Figure 7-C5 Simulated Drain Flow for Additional Scenarios Figure 7-C6 Simulated Salton Sea Net Outflow for Additional Scenarios Figure 7-C7 Additional Scenarios Hydrographs, West Valley 2020-2069 Figure 7-C8 Additional Scenarios Hydrographs, East Valley 2020-2069 Figure 7-C9 Change in Groundwater Levels, 2009-2045 Five Year Scenario Figure 7-C10 Change in Groundwater Levels, 2009-2045 Future Projects Scenario Figure 7-C11 Change in Groundwater Levels, 2009-2045 Expanded Agriculture Scenario
Figure 7-C1
Model Inflows and
Outflows By Scenario
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
F
i
g
u
r
e
7 -
C
1 A
n
n
u
a
l
M
o
d
e
l
W
a
t
e
r
B
u
d
g
e
t
f
o
r
A
d
d
i
t
i
o
n
a
l
S
c
e
n
a
r
i
o
s
.
g
p
j
-500,000
0 500,000
-400,000
-300,000
-200,000
-100,000
100,000
200,000
300,000
400,000
Av
e
r
a
g
e
A
n
n
u
a
l
W
a
t
e
r
B
u
d
g
e
t
C
o
m
p
o
n
e
n
t
(
A
F
Y
)
Baseline 5 year Future Expanded Ag
25 Year Average (2020-2045)
Thomas E Levy GRF
Whitewater GRF
Palm Desert GRF
EVRA Reuse
Wastewater
Agriculture Return Flow
Golf Course Return Flow
Municipal Return Flow
Natural Infiltration (less diversions)
Subsurface Inflow
Pumping
Drains
Outflow to Salton Sea
Evapotranspiration
Figure 7-C2
Cumulative Change in
Storage for
Additional Scenarios
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
F
i
g
u
r
e
7 -
C
2 C
u
m
u
l
a
t
i
v
e
C
h
a
n
g
e
i
n
S
t
o
r
a
g
e
f
o
r
A
d
d
i
t
i
o
n
a
l
S
c
e
n
a
r
i
o
s
.
g
p
j
-1,000,000
0 1,000,000
2,000,000
3,000,000
-800,000
-600,000
-400,000
-200,000
200,000
400,000
600,000
800,000
1,200,000
1,400,000
1,600,000
1,800,000
2,200,000
2,400,000
2,600,000
2,800,000
Cu
m
u
l
a
t
i
v
e
C
h
a
n
g
e
i
n
S
t
o
r
a
g
e
(
A
c
r
e
-
F
e
e
t
)
2020 2025 2030 2035 2040 2045 2050 2055 2060 2065 2070
Simulated 2020-2070 Cumulative Change in Storage
Baseline Cumulative Change in Storage
Five Year Plan Term Cumulative Change in Storage
Future Projects Cumulative Change in Storage
Expanded Agriculture Cumulative Change in Storage
Figure 7-C3
Total Model Inflow for
Additional Scenarios
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
F
i
g
u
r
e
7 -
C
3 T
o
t
a
l
M
o
d
e
l
I
n
f
l
o
w
f
o
r
A
d
d
i
t
i
o
n
a
l
S
c
e
n
a
r
i
o
s
.
g
p
j
250,000
550,000
300,000
350,000
400,000
450,000
500,000
An
n
u
a
l
I
n
f
l
o
w
(
A
c
r
e
-
F
e
e
t
p
e
r
Y
e
a
r
)
2020 2025 2030 2035 2040 2045 2050 2055 2060 2065 2070
Simulated 2020-2070 Total Inflow 2020-2070
Baseline Inflow
Five Year Plan Inflow
Future Projects Inflow
Expanded Agriculture Inflow
Figure 7-C4
Simulated Pumping
for Additional Scenarios
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
F
i
g
u
r
e
7 -
C
4 S
i
m
u
l
a
t
e
d
P
u
m
p
i
n
g
f
o
r
A
d
d
i
t
i
o
n
a
l
S
c
e
n
a
r
i
o
s
.
g
p
j
200,000
400,000
220,000
240,000
260,000
280,000
300,000
320,000
340,000
360,000
380,000
An
n
u
a
l
P
u
m
p
i
n
g
(
A
c
r
e
-
F
e
e
t
p
e
r
Y
e
a
r
)
2020 2025 2030 2035 2040 2045 2050 2055 2060 2065 2070
Simulated 2020-2070 Pumping
Baseline Pumping
Five Year Plan Pumping
Future Projects Pumping
Expanded Agriculture Pumping
Figure 7-C5
Simulated Drain Flow
for Additional Scenarios
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
F
i
g
u
r
e
7 -
C
5 S
i
m
u
l
a
t
e
d
D
r
a
i
n
F
l
o
w
f
o
r
A
d
d
i
t
i
o
n
a
l
S
c
e
n
a
r
i
o
s
.
g
p
j
20,000
120,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
An
n
u
a
l
F
l
o
w
R
a
t
e
(
A
c
r
e
-
F
e
e
t
p
e
r
Y
e
a
r
)
1990 2000 2010 2020 2030 2040 2050 2060 2070
Simulated 2020-2070 Drain Flow
Simulated Drain Flow Baseline
Simulated Drain Flow Five Year Plan
Simulated Drain Flow Future Projects
Simulated Drain Flow Expanded Agriculture
Measured/Estimated Drain Flow
Figure 7-C6
Simulated Salton Sea
Net Outflow for
Additional Scenarios
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
F
i
g
u
r
e
7 -
C
6 S
i
m
u
l
a
t
e
d
S
a
l
t
o
n
S
e
a
N
e
t
O
u
t
f
l
o
w
f
o
r
A
d
d
i
t
i
o
n
a
l
S
c
e
n
a
r
i
o
s
.
g
p
j
0 10,000
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
An
n
u
a
l
S
a
l
t
o
n
S
e
a
I
n
f
l
o
w
a
n
d
O
u
t
f
l
o
w
R
a
t
e
s
(
A
c
r
e
-
F
e
e
t
p
e
r
Y
e
a
r
)
2020 2025 2030 2035 2040 2045 2050 2055 2060 2065 2070
Simulated 2020-2070 Salton Sea Outflow
Simulated Drain Flow Baseline
Simulated Drain Flow Five Year Plan
Simulated Drain Flow Future Projects
Simulated Drain Flow Expanded Agriculture
Figure 7-C7Additional ScenariosHydrographs, West Valley2020-2069 FINAL
Garnet
H
i
l
l
Palm
S
p
r
i
n
g
s
Indio
H
i
l
l
s
Thous
a
n
d
P
a
l
m
s
Therm
a
l
03S04E17K01S
03S04E20F01S
03S04E34R01S
03S05E30G01S
04S05E17Q02S
04S05E35G03S
05S06E16A02S
05S07E08Q01S
Model Results Hydrographs
Indio Subbasin
Indio Subbasin Subareas
0 50
100
150
200
250
300
1995 2005 2015 2025 2035 2045 2055 2065
04S05E35G03S
100
150
200
250
300
350
400
1995 2005 2015 2025 2035 2045 2055 2065
04S05E17Q02S
-100
-50
0 50
100
150
200
1995 2005 2015 2025 2035 2045 2055 2065
05S06E16A02S
250
300
350
400
450
500
550
1995 2005 2015 2025 2035 2045 2055 2065
03S05E30G01S
-200
-150
-100
-50
0 50
100
1995 2005 2015 2025 2035 2045 2055 2065
05S07E08Q01S
250
300
350
400
450
500
550
1995 2005 2015 2025 2035 2045 2055 2065
03S04E34R01S
500
550
600
650
700
750
800
1995 2005 2015 2025 2035 2045 2055 2065
03S04E20F01S
500
550
600
650
700
750
800
1995 2005 2015 2025 2035 2045 2055 2065
03S04E17K01S Historical Elevation
Baseline
Five Year Plan
Future Projects
Expanded Agriculture
(N
0 3
Miles
O
a
s
i
s
Ba
r
t
o
n
C
a
n
y
o
n
Th
e
r
m
a
l
Riverside
San Diego
06S08E22D02S
07S07E02G02S
07S09E18H01S
08S09E07N03S
-300
-250
-200
-150
-100
-50
0 1995 2005 2015 2025 2035 2045 2055 2065
07S09E18H01S
-300
-250
-200
-150
-100
-50
0 1995 2005 2015 2025 2035 2045 2055 2065
08S09E07N03S
-200
-150
-100
-50
0 50
100
1995 2005 2015 2025 2035 2045 2055 2065
07S07E02G02S
-200
-150
-100
-50
0 50
100
1995 2005 2015 2025 2035 2045 2055 2065
06S08E22D02S
Figure 7-C8Additional ScenariosHydrographs, East Valley2020-2069 FINAL
Historical Elevation
Baseline
Five Year Plan
Future Projects
Expanded Agriculture
(N
0 3
Miles
Model Results Hydrographs
Indio Subbasin
Indio Subbasin Subareas
California County
Figure 7-C9Change in Groundwater Levels2009-2045Five Year Plan Scenario FINALModel Domain
Indio Subbasin
California County
Garnet Hill Fault
(N
0 6
Scale in Miles
Groundwater Level Change
> 150'
125' to 150'
100' to 125'
75' to 100'
50' to 75'
25' to 50'
0' to 25'
-0' to -25'
-25' to -50'
> -50'
Figure 7-C10Change in Groundwater Levels2009-2045Future Projects Scenario FINALModel Domain
Indio Subbasin
California County
Garnet Hill Fault
(N
0 6
Scale in Miles
Groundwater Level Change
> 150'
125' to 150'
100' to 125'
75' to 100'
50' to 75'
25' to 50'
0' to 25'
-0' to -25'
-25' to -50'
> -50'
Figure 7-C11Change in Groundwater Levels2009-2045Expanded Agriculture Scenario FINALModel Domain
Indio Subbasin
California County
Garnet Hill Fault
(N
0 6
Scale in Miles
Groundwater Level Change
> 150'
125' to 150'
100' to 125'
75' to 100'
50' to 75'
25' to 50'
0' to 25'
-0' to -25'
-25' to -50'
> -50'
This page intentionally left blank.
APPENDIX 9-A
KEY WELL GROUNDWATER LEVEL HYDROGRAPHS WITH MINIMUM THRESHOLDS
This page intentionally left blank.
Note:
Minimum groundwater elevation occured in 1968.
Appendix 9A-1
Groundwater Elevation
Hydrograph
334 - 03S04E17K01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
610
730
620
630
640
650
660
670
680
690
700
710
720
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
334 - 03S04E17K01S
Groundwater Elevation (feet msl)
Minimum Threshold (feet msl)
Appendix 9A-2
Groundwater Elevation
Hydrograph
756 - 03S04E22A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
550
650
560
570
580
590
600
610
620
630
640
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
756 - 03S04E22A01S
Appendix 9A-3
Groundwater Elevation
Hydrograph
271 - 03S04E34R01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
240
360
250
260
270
280
290
300
310
320
330
340
350
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
271 - 03S04E34R01S
Appendix 9A-4
Groundwater Elevation
Hydrograph
337 - 03S05E30G01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
350
450
360
370
380
390
400
410
420
430
440
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
337 - 03S05E30G01S
Appendix 9A-5
Groundwater Elevation
Hydrograph
273 - 04S04E13C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
150
300
160
170
180
190
200
210
220
230
240
250
260
270
280
290
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
273 - 04S04E13C01S
Appendix 9A-6
Groundwater Elevation
Hydrograph
274 - 04S04E24D01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
140
240
150
160
170
180
190
200
210
220
230
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
274 - 04S04E24D01S
Appendix 9A-7
Groundwater Elevation
Hydrograph
41 - 04S05E09B01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
140
240
150
160
170
180
190
200
210
220
230
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
41 - 04S05E09B01S
Appendix 9A-8
Groundwater Elevation
Hydrograph
350 - 04S05E15R02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
90 190
100
110
120
130
140
150
160
170
180
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
350 - 04S05E15R02S
Appendix 9A-9
Groundwater Elevation
Hydrograph
282 - 04S05E17Q02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
120
220
130
140
150
160
170
180
190
200
210
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
282 - 04S05E17Q02S
Appendix 9A-10
Groundwater Elevation
Hydrograph
29 - 04S05E28F02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
80 180
90 100
110
120
130
140
150
160
170
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
29 - 04S05E28F02S
Appendix 9A-11
Groundwater Elevation
Hydrograph
367 - 04S05E29F01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
100
200
110
120
130
140
150
160
170
180
190
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
367 - 04S05E29F01S
Appendix 9A-12
Groundwater Elevation
Hydrograph
18 - 04S05E35G03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
50 150
60 70
80 90
100
110
120
130
140
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
18 - 04S05E35G03S
Appendix 9A-13
Groundwater Elevation
Hydrograph
56 - 04S06E18R01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
20 120
30 40
50 60
70 80
90 100
110
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
56 - 04S06E18R01S
Appendix 9A-14
Groundwater Elevation
Hydrograph
61 - 04S06E20M02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
0 100
10 20
30 40
50 60
70 80
90 Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
61 - 04S06E20M02S
Appendix 9A-15
Groundwater Elevation
Hydrograph
50 - 04S06E32N02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-110
-10
-100
-90
-80
-70
-60
-50
-40
-30
-20
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
50 - 04S06E32N02S
Appendix 9A-16
Groundwater Elevation
Hydrograph
406 - 04S06E35P01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-50
50 -40
-30
-20
-10
0 10
20 30
40 Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
406 - 04S06E35P01S
Appendix 9A-17
Groundwater Elevation
Hydrograph
70 - 05S05E12H02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
0 100
10 20
30 40
50 60
70 80
90 Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
70 - 05S05E12H02S
Appendix 9A-18
Groundwater Elevation
Hydrograph
94 - 05S06E12N01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-80
20 -70
-60
-50
-40
-30
-20
-10
0 10
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
94 - 05S06E12N01S
Appendix 9A-19
Groundwater Elevation
Hydrograph
87 - 05S06E16A02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-50
50 -40
-30
-20
-10
0 10
20 30
40 Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
87 - 05S06E16A02S
Appendix 9A-20
Groundwater Elevation
Hydrograph
104 - 05S06E24G01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-100
0 -90
-80
-70
-60
-50
-40
-30
-20
-10
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
104 - 05S06E24G01S
Appendix 9A-21
Groundwater Elevation
Hydrograph
112 - 05S06E29C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-50
50 -40
-30
-20
-10
0 10
20 30
40 Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
112 - 05S06E29C01S
Appendix 9A-22
Groundwater Elevation
Hydrograph
255 - 05S07E04A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-80
20 -70
-60
-50
-40
-30
-20
-10
0 10
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
255 - 05S07E04A01S
Appendix 9A-23
Groundwater Elevation
Hydrograph
165 - 05S07E06B04S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-80
20 -70
-60
-50
-40
-30
-20
-10
0 10
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
165 - 05S07E06B04S
Appendix 9A-24
Groundwater Elevation
Hydrograph
511 - 05S07E08Q01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-90
10 -80
-70
-60
-50
-40
-30
-20
-10
0 Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
511 - 05S07E08Q01S
Appendix 9A-25
Groundwater Elevation
Hydrograph
299 - 05S07E24M04S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-110
-10
-100
-90
-80
-70
-60
-50
-40
-30
-20
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
299 - 05S07E24M04S
Appendix 9A-26
Groundwater Elevation
Hydrograph
535 - 05S07E27L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-150
-50
-140
-130
-120
-110
-100
-90
-80
-70
-60
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
535 - 05S07E27L01S
Appendix 9A-27
Groundwater Elevation
Hydrograph
146 - 05S07E28E01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-100
0 -90
-80
-70
-60
-50
-40
-30
-20
-10
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
146 - 05S07E28E01S
Appendix 9A-28
Groundwater Elevation
Hydrograph
150 - 05S07E31P01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-120
-20
-110
-100
-90
-80
-70
-60
-50
-40
-30
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
150 - 05S07E31P01S
Appendix 9A-29
Groundwater Elevation
Hydrograph
167 - 05S07E32B01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-160
-60
-150
-140
-130
-120
-110
-100
-90
-80
-70
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
167 - 05S07E32B01S
Appendix 9A-30
Groundwater Elevation
Hydrograph
559 - 05S08E33D01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-170
-70
-160
-150
-140
-130
-120
-110
-100
-90
-80
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
559 - 05S08E33D01S
Appendix 9A-31
Groundwater Elevation
Hydrograph
567 - 06S07E02D02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-160
-60
-150
-140
-130
-120
-110
-100
-90
-80
-70
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
567 - 06S07E02D02S
Appendix 9A-32
Groundwater Elevation
Hydrograph
174 - 06S07E06B01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-150
-50
-140
-130
-120
-110
-100
-90
-80
-70
-60
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
174 - 06S07E06B01S
Appendix 9A-33
Groundwater Elevation
Hydrograph
190 - 06S07E13M02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-120
-20
-110
-100
-90
-80
-70
-60
-50
-40
-30
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
190 - 06S07E13M02S
Appendix 9A-34
Groundwater Elevation
Hydrograph
183 - 06S07E16A02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-180
-80
-170
-160
-150
-140
-130
-120
-110
-100
-90
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
183 - 06S07E16A02S
Appendix 9A-35
Groundwater Elevation
Hydrograph
582 - 06S07E23F01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-170
-70
-160
-150
-140
-130
-120
-110
-100
-90
-80
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
582 - 06S07E23F01S
Appendix 9A-36
Groundwater Elevation
Hydrograph
587 - 06S07E29B01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-180
-80
-170
-160
-150
-140
-130
-120
-110
-100
-90
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
587 - 06S07E29B01S
Appendix 9A-37
Groundwater Elevation
Hydrograph
594 - 06S07E35L02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-180
-80
-170
-160
-150
-140
-130
-120
-110
-100
-90
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
594 - 06S07E35L02S
Appendix 9A-38
Groundwater Elevation
Hydrograph
198 - 06S08E05R02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-110
-10
-100
-90
-80
-70
-60
-50
-40
-30
-20
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
198 - 06S08E05R02S
Appendix 9A-39
Groundwater Elevation
Hydrograph
607 - 06S08E12Q01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-140
-40
-130
-120
-110
-100
-90
-80
-70
-60
-50
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
607 - 06S08E12Q01S
Appendix 9A-40
Groundwater Elevation
Hydrograph
192 - 06S08E22D02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-180
-80
-170
-160
-150
-140
-130
-120
-110
-100
-90
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
192 - 06S08E22D02S
Appendix 9A-41
Groundwater Elevation
Hydrograph
616 - 06S08E25Q01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-100
-190
-180
-170
-160
-150
-140
-130
-120
-110
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
616 - 06S08E25Q01S
Appendix 9A-42
Groundwater Elevation
Hydrograph
619 - 06S08E31P01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-100
-190
-180
-170
-160
-150
-140
-130
-120
-110
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
619 - 06S08E31P01S
Appendix 9A-43
Groundwater Elevation
Hydrograph
627 - 06S09E32Q01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-100
-190
-180
-170
-160
-150
-140
-130
-120
-110
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
627 - 06S09E32Q01S
Appendix 9A-44
Groundwater Elevation
Hydrograph
633 - 07S07E02G02S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-180
-80
-170
-160
-150
-140
-130
-120
-110
-100
-90
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
633 - 07S07E02G02S
Appendix 9A-45
Groundwater Elevation
Hydrograph
642 - 07S08E10P01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-210
-110
-200
-190
-180
-170
-160
-150
-140
-130
-120
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
642 - 07S08E10P01S
Appendix 9A-46
Groundwater Elevation
Hydrograph
200 - 07S08E17G01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-100
-190
-180
-170
-160
-150
-140
-130
-120
-110
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
200 - 07S08E17G01S
Appendix 9A-47
Groundwater Elevation
Hydrograph
687 - 07S08E33B01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-220
-120
-210
-200
-190
-180
-170
-160
-150
-140
-130
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
687 - 07S08E33B01S
Appendix 9A-48
Groundwater Elevation
Hydrograph
206 - 07S09E07J01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-250
-150
-240
-230
-220
-210
-200
-190
-180
-170
-160
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
206 - 07S09E07J01S
Appendix 9A-49
Groundwater Elevation
Hydrograph
707 - 07S09E14C01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-200
-100
-190
-180
-170
-160
-150
-140
-130
-120
-110
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
707 - 07S09E14C01S
Appendix 9A-50
Groundwater Elevation
Hydrograph
708 - 07S09E16M03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-270
-170
-260
-250
-240
-230
-220
-210
-200
-190
-180
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
708 - 07S09E16M03S
Appendix 9A-51
Groundwater Elevation
Hydrograph
712 - 07S09E18H01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-270
-170
-260
-250
-240
-230
-220
-210
-200
-190
-180
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
712 - 07S09E18H01S
Appendix 9A-52
Groundwater Elevation
Hydrograph
9 - 07S09E30R01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-220
-120
-210
-200
-190
-180
-170
-160
-150
-140
-130
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
9 - 07S09E30R01S
Appendix 9A-53
Groundwater Elevation
Hydrograph
727 - 08S08E03L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-230
-130
-220
-210
-200
-190
-180
-170
-160
-150
-140
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
727 - 08S08E03L01S
Appendix 9A-54
Groundwater Elevation
Hydrograph
745 - 08S08E24L01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-270
-170
-260
-250
-240
-230
-220
-210
-200
-190
-180
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
745 - 08S08E24L01S
Appendix 9A-55
Groundwater Elevation
Hydrograph
11 - 08S09E07N03S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-260
-160
-250
-240
-230
-220
-210
-200
-190
-180
-170
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
11 - 08S09E07N03S
Appendix 9A-56
Groundwater Elevation
Hydrograph
750 - 08S09E30A01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-280
-180
-270
-260
-250
-240
-230
-220
-210
-200
-190
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
750 - 08S09E30A01S
Appendix 9A-57
Groundwater Elevation
Hydrograph
754 - 08S09E33N01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-280
-180
-270
-260
-250
-240
-230
-220
-210
-200
-190
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
754 - 08S09E33N01S
Appendix 9A-57
Groundwater Elevation
Hydrograph
754 - 08S09E33N01S
FINAL
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
2 -
A
l
t
e
r
n
a
t
i
v
e
P
l
a
n
U
p
d
a
t
e
\
G
R
A
P
H
I
C
S
\
C
h
a
p
t
e
r
_
9 _
A
p
p
e
n
d
i
x
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
-280
-180
-270
-260
-250
-240
-230
-220
-210
-200
-190
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1990 1995 2000 2005 2010 2015 2020
Year
754 - 08S09E33N01S
This page intentionally left blank.
Prepared by
9655 Chesapeake Drive, Suite 320
San Diego, CA 92123
woodardcurran.com
2490 Mariner Square Loop, Suite 215
Alameda, CA 94501
toddgroundwater.com
2022 Indio Subbasin Alternative Plan Update Annual Report for Water Year 2020-2021 Public WorkshopMarch 17, 2022
GoToMeeting –Quick How To
Your screen should look like this:
Turn on/off your Mic (mute) and Camera (video) using the controls along the bottom You may need to wiggle your mouse to make the controls appear For Callers: use *6 to unmute on the phone
2 GoToMeeting –How to Ask a Question
Our organizer will mute everyone at the beginning of the meeting Let us know you have a question by clicking the Chat icon in the top right Click on Enter your message, type your message and hit SEND Once we receive your Chat, we will call on you and answer your question For Callers: when asked for questions or comments, use *6 to unmute 3 Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
4 Project Consultants
Todd Groundwater
Woodard & Curran
Indio Subbasin Groundwater Sustainability Agencies (GSAs) Coachella Valley Water District
Coachella Water Authority
Desert Water Agency
Indio Water Authority
Indio Subbasin Team
`
5 Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
6 Indio Subbasin Annual Report for WY 2020-2021
Annual Report is required by Sustainable Groundwater Management Act (SGMA) General information
Subbasin conditions
Implementation progress of projects and management actions (PMAs) 5th Annual Report (1st report following submittal of Indio Subbasin 2022 Alternative Plan Update) Covers WY 2020-2021 (Oct. 1, 2020 –Sept. 30, 2021)
Will be submitted to DWR by April 1, 2022
7 8
Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
9 Groundwater Evaluation Data
Groundwater Elevations from 380 wells were used to develop contour maps and change in storage maps 2022 Plan Update identified 57 Key Wells to track groundwater sustainability Each well has a minimum threshold (MT—set at recent observed lowest elevation) Current groundwater elevations were compared to the MTs •Levels in all wells were above the MT
•Hydrographs of each of these wells are included in the report as an Appendix 10 11
Questions?
12 Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
13 Groundwater Extractions
Groundwater extractions are metered for most uses except Minimal pumpers
Tribal trust lands
Groundwater pumping increased 7 percent over last water year, which was a dry year with increased tourism Water Use
Sector
Groundwater
Extractions
(AF)
Method of
Measurement
Accuracy of
Measurement
Agriculture1 46,561 100% metered ±2%
Industrial2 1,288 15% metered ±2%
85% estimated ±50%
Urban3 236,002 99% metered ±2%
1% estimated ±50%
Undetermined4 1,500 100% estimated ±50%
Total Production 285,351 14
Questions?
15 Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
16 Multiple Water Sources
Capture and recharge of Whitewater River stormflows began in 1918 Coachella Canal completed in 1949
CVWD and DWA contract for State Water Project (SWP) water in 1963 Recharge at Whitewater River Groundwater Replenishment Facility (GRF) begins in 1973 Water recycling began in 1965
17 Coachella Canal construction
Whitewater River GRF 17
Local Surface Water
DWA stream diversions
Snow, Falls, and Chino Creeks
Subsurface flows from Whitewater River Canyon
719 AF surface water use in DWA’s service area
49% agriculture
51% urban
WY 2020-2021 Direct Use of Local Surface Water in the Indio Subbasin Snow Creek
18 Imported Water –Direct Use
CVWD receives Colorado River water from Coachella Canal 287,563 AF imported water for direct use in Plan Area
85% agriculture
15% urban
Coachella Canal
WY 2020-2021 Imported Water for Direct Use in Plan Area 19 Imported Water –Groundwater Replenishment
Two sources of water used for replenishment:
DWA and CVWD receive State Water Project exchange water from Colorado River Aqueduct (CRA) CVWD receives Colorado River water from Coachella Canal 154,848 AF imported water for replenishment
10,789 AF at Palm Desert GRF
37,878 AF at Thomas E. Levy GRF
106,181 AF at Whitewater River GRF
WY 2020-2021 Imported Water for Replenishment in Plan Area
WWR-GRF
20 Recycled Water
Three water reclamation plants (WRPs) provide recycled water Palm Springs WWTP/DWA WRP
CVWD WRP-7
CVWD WRP-10
14,000 AF recycled water produced
100% urban
WY 2020-2021 Recycled Water Use in the Indio Subbasin
DWA WRP
21 Questions?
22 Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
23 Total Water Use
WY 2020-2021 Water Demand and Supply –Plan Area
24 Total Water Use
Total Water Demand Actual and Forecasted –Plan Area
25 Questions?
26 Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
27 Change in Groundwater Storage
Comparison of Inflows and Outflows
Inflows
Return Flows
Replenishment
Natural Infiltration
Subsurface Flow
WW Percolation
Outflows
Pumping
Drains
Evapotranspiration (ET)
Subsurface Flow
28 Change in Groundwater Storage
Annual change in storage
Slight positive (5,954 AF)
Average change in storage
Since 2009, 10-year average is positive and 20-year average is near balanced Shows the Indio Subbasin is sustainable
29 Change in Groundwater Levels
Maps show change in groundwater levels
One year change (next slide)
Long-term change since 2009 –historical lows (following slide) Change in groundwater levels is a proxy for change in storage Based on measured water levels at 380 wells throughout the Indio Subbasin
One Year Change
Groundwater levels generally increased in the past water year Declines in the norther part of the Subbasin of about 10-15 feet due to dry-year reductions in replenishment Declines in the eastern part of the Subbasin were less than 5 feet WY 2020 to WY 2021
31 Long-Term Change
Basin-wide increases since 2009 historic lows
Water levels have increased or stabilized
Very localized declines in Mid-Valley area
WY 2009 to WY 2021
32 Questions?
33 Agenda
Welcome and Introductions
Annual Report Status
Groundwater Elevation Data
Groundwater Extractions
Surface Water
Total Water Use
Change in Groundwater Storage
Plan Implementation Progress
Public Comment
34 Projects & Management Actions
1: Urban Water Conservation
2: Golf Water Conservation
3: Agricultural Water Conservation
4: Increased Surface Water Diversion
5: Delta Conveyance Facility
6: Lake Perris Seepage
7: Sites Reservoir
8: Future Supplemental Water Acquisitions
9: EVRA Potable Reuse
10: Mid-Valley Pipeline Direct Customers
11: East Golf Expansion
12: Oasis Distribution System
13: WRP-10 Recycled Water Delivery
14: WRP-10 Tertiary Expansion
15: Canal Water Pump Station Upgrade
16: WRP-7 Recycled Water Delivery
17: WRP-4 Tertiary Expansion & Delivery
18: DWA WRP Recycled Water Delivery
19: PD-GRF Phase 2 Expansion
20: TEL-GRF Expansion
21: WWR-GRF Operation
22: Eliminate Wastewater Percolation
23: Wellhead Treatment
24: Small Water System Consolidations
25: Septic to Sewer Conversions
26: CV-SNMP GW Monitoring Program Workplan
27: CV-SNMP Development Workplan
28: Colorado River Salinity Forum
29: Source Water Protection
Water Supply Development
Source Substitution & Replenishment Water Quality ProtectionWater Conservation 35 Projects & Management Actions –Progress in WY 2020-2021 Water Supply Development Source Substitution & Replenishment Water Quality ProtectionWater Conservation 36 Questions?
37 Public Comment
Input and feedback are welcomed
For Callers –you may need to press *6 to unmute
38 Next Steps
WY 2022 Annual Report can be downloaded:
Indio Subbasin Annual Report for WY 2020-2021 Council/Board Presentation or Adoption Coachella Valley Water District –March 8, 2022
Coachella Water Authority –TBD
Desert Water Agency –April 19, 2022
Indio Water Authority –April 20, 2022
www.IndioSubbasinSGMA.org
39 Stay Involved –Visit our Website
www.IndioSubbasinSGMA.org 40
INDIO SUBBASINANNUAL REPORT
Final | February 2022
for Water Year2020–2021
FINAL
INDIO SUBBASIN ANNUAL REPORT
FOR WATER YEAR 2020-2021
COACHELLA VALLEY WATER DISTRICT
COACHELLA WATER AUTHORITY
DESERT WATER AGENCY
INDIO WATER AUTHORITY
February 2022
2490 Mariner Square Loop, Suite 215
Alameda, CA 94501
www.toddgroundwater.com
9655 Chesapeake Drive, Suite 320
San Diego, CA 92123
www.woodardcurran.com
Alternative Annual Report Elements Guide -
Indio Subbasin Annual Report for Water Year 2020-2021
California
Code of
Regulations
- GSP
Regulation
Sections
Alternative Elements
Document
which
attachment(s)
contains the
applicable
alternative
element.
Document which section(s), page number(s),
or briefly describe why that Alternative
element does not apply to the entity.
Article 7 Annual Reports and Periodic Evaluations by the Agency § 356.2 Annual Reports
Each Agency shall submit an annual report to the Department by April 1 of each year following the adoption of the Plan. The annual report shall include the following components for the preceding water year:
(a) General information, including an executive summary and a location map depicting the basin covered by the report.
Annual Report An executive summary is provided as the first section of the Annual Report. Maps depicting the
Indio Subbasin are shown on Figures 1‐1 and 1‐2.
(b) A detailed description and graphical representation of the following conditions of the basin managed in the Plan:
(1) Groundwater elevation data from monitoring wells identified in the monitoring network shall be analyzed and displayed as follows:
(A) Groundwater elevation contour maps for each principal aquifer in the basin illustrating, at a minimum, the seasonal high and seasonal low groundwater conditions. Annual Report
A groundwater contour map is provided on Figure
3‐2 for WY 2020 ‐2021. Seasonal changes are
generally not significant in this large Subbasin, as
shown in hydrographs provided on Figure 3‐2.
(B) Hydrographs of groundwater elevations and water year type using historical data to the greatest extent available, including from January 1, 2015, to current reporting year. Annual Report
Representative hydrographs are provided on Figure
3‐2. Water year type is not provided because the
Subbasin is not directly affected by runoff
conditions in Sacramento and San Joaquin River,
but instead receives water from the Colorado River.
(2) Groundwater extraction for the preceding water year. Data shall be collected using the best available measurement methods and shall be presented in a table that summarizes groundwater extractions by water use sector and identifies the method of measurement (direct or estimate) and accuracy of measurements, and a map that illustrates the general location and volume of groundwater extractions.
Annual Report
Groundwater extraction by water use section is
described in Section 4 of the Annual Report.
Extractions, methods of measurement, and
accuracy of measurements are summarized in Table
4‐1. A map of groundwater extractions is provided
on Figure 4‐1.
(3) Surface water supply used or available for use, for groundwater recharge or in‐lieu use shall be reported based on quantitative data that describes the annual volume and sources for the preceding water year.
Annual Report
Surface water supply and use is described in
Section 5. Direct use of surface water is
summarized in Table 5‐3.
(4) Total water use shall be collected using the best available measurement methods and shall be reported in a table that summarizes total water use by water use sector, water source type, and identifies the method of measurement (direct or estimate) and accuracy of measurements. Existing water use data from the most recent Urban Water Management Plans or Agricultural Water Management Plans within the basin may be used, as long as the data are reported by water year.
Annual Report
Total water use is described in Section 6. Table 6‐1
summarizes water sources for each water use
sector and provides the method of measurement
and accuracy of measurements.
(5) Change in groundwater in storage shall include the following:
(A) Change in groundwater in storage maps for each principal aquifer in the basin.
Annual Report There is one principal aquifer for the Indio Subbasin. Change in storage is described in Section
7 and summarized on Figure 7‐1.
(B) A graph depicting water year type, groundwater use, the annual change in groundwater in storage, and the cumulative change in groundwater in storage for the basin based on historical data to the greatest extent available, including from January 1, 2015, to the current reporting year.
Annual Report Historical annual change in groundwater storage since 1970 is depicted in graphical form on Figure
7‐2. Cumulative change in storage since 1970 is
presented depicted in graphical form on Figure 7‐3.
(c) A description of progress towards implementing the Plan, including achieving interim milestones, and implementation of projects or management actions since the previous annual report.
Annual Report A description of progress toward implementing the plan is provided in Section 8. A detailed status for
WY 2020‐2021 is provided in Table 8‐2.
Indio Subbasin Annual Report
for Water Year 2020-21 i TODD / W&C
SIGNATURE PAGE
Sally McCraven, PG, CHG, CEG
Consulting Hydrogeologist
Todd Groundwater
Maureen Reilly, PE
Professional Engineer
Todd Groundwater
6/30/23
Indio Subbasin Annual Report
for Water Year 2020-21 ii TODD / W&C
TABLE OF CONTENTS
EXECUTIVE SUMMARY .................................................................................................................................. 1 ES‐1 Background ................................................................................................................................... 1 ES‐2 WY 2020‐2021 Overview .................................................................................................................. 2 ES‐3 Indio Subbasin Setting .................................................................................................................. 2 ES‐4 Groundwater Elevation Data ........................................................................................................ 3 ES‐5 Groundwater Extractions ............................................................................................................. 5 ES‐6 Surface Water .............................................................................................................................. 6 ES‐5.1 Local Surface Water .............................................................................................................. 6 ES‐5.2 Colorado River Water ............................................................................................................ 7 ES‐5.3 State Water Project Water .................................................................................................... 7 ES‐5.4 Recycled Water ..................................................................................................................... 7 ES‐7 Total Water Use ........................................................................................................................... 7 ES‐8 Groundwater Balance and Change in Groundwater Storage ...................................................... 9 ES‐9 Description of Progress .............................................................................................................. 11
1. INTRODUCTION .................................................................................................................................. 1‐1
1.1 Report Organization ................................................................................................................... 1‐1
1.2 Implementation of the Sustainable Groundwater Management Act ........................................ 1‐1
1.2.1 Formation of GSAs by Local Agencies in the Indio Subbasin ............................................. 1‐3
1.2.2 Submission of the Alternative Plan and 2022 Alternative Plan Update ............................ 1‐3
1.2.3 Annual Reporting ............................................................................................................... 1‐6
2. INDIO SUBBASIN SETTING .................................................................................................................. 2‐1
2.1 Climate ....................................................................................................................................... 2‐1
2.2 Coachella Valley Groundwater Basin ......................................................................................... 2‐1
2.2.1 Subbasins and Subareas of the Coachella Valley Groundwater Basin ............................... 2‐2
2.2.2 Geology .............................................................................................................................. 2‐4
2.2.3 Basin Storage Capacity ....................................................................................................... 2‐4
2.3 Indio Subbasin Description ........................................................................................................ 2‐4
2.3.1 Garnet Hill Subarea ............................................................................................................ 2‐6
2.3.2 Palm Springs Subarea ......................................................................................................... 2‐6
2.3.3 Thermal Subarea ................................................................................................................ 2‐7
2.3.4 Thousand Palms Subarea ................................................................................................. 2‐10
Indio Subbasin Annual Report
for Water Year 2020-21 iii TODD / W&C
2.3.5 Oasis Subarea ................................................................................................................... 2‐10
3. GROUNDWATER ELEVATION DATA .................................................................................................... 3‐1
3.1 Monitoring Wells ....................................................................................................................... 3‐1
3.2 Key Wells .................................................................................................................................... 3‐3
3.3 Groundwater Elevations, Flow, and Trends ............................................................................... 3‐7
3.3.1 Artesian Conditions ............................................................................................................ 3‐7
3.4 Land Subsidence ...................................................................................................................... 3‐10
4. GROUNDWATER EXTRACTIONS ......................................................................................................... 4‐1
5. SURFACE WATER ................................................................................................................................ 5‐1
5.1 Local Precipitation ...................................................................................................................... 5‐1
5.2 Local Streamflow ........................................................................................................................ 5‐1
5.2.1 Direct Use of Local Surface Water ..................................................................................... 5‐1
5.3 Imported Water Deliveries ........................................................................................................ 5‐6
5.3.1 Colorado River Water ......................................................................................................... 5‐6
5.3.2 State Water Project (Exchange Water) .............................................................................. 5‐8
5.3.3 Total Imported Deliveries ................................................................................................ 5‐10
5.4 Recycled Water ........................................................................................................................ 5‐12
6. TOTAL WATER USE ............................................................................................................................. 6‐1
7. CHANGE IN GROUNDWATER STORAGE ............................................................................................. 7‐1
7.1 Groundwater Balance ................................................................................................................ 7‐1
7.1.1 Groundwater Inflows ......................................................................................................... 7‐1
7.1.2 Groundwater Outflows ...................................................................................................... 7‐4
7.1.3 Annual Change in Groundwater Storage ........................................................................... 7‐7
7.2 CHANGE IN GROUNDWATER ELEVATION MAPS ...................................................................... 7‐11
7.2.1 One‐Year Change (WY 2019‐2020 to WY 2020‐2021) ..................................................... 7‐11
7.2.2 Twelve‐Year Change (WY 2008‐2009 to WY 2020‐2021) ................................................ 7‐14
8. DESCRIPTION OF PROGRESS .............................................................................................................. 8‐1
8.1 Implementation of Projects and Management Actions ............................................................. 8‐1
8.2 Water Conservation ................................................................................................................... 8‐2
8.3 Water Supply Development ....................................................................................................... 8‐4
8.3.1 Surface Water .................................................................................................................... 8‐4
8.3.2 SWP Water ......................................................................................................................... 8‐4
8.3.3 Potable Reuse .................................................................................................................... 8‐5
Indio Subbasin Annual Report
for Water Year 2020-21 iv TODD / W&C
8.4 Source Substitution and Replenishment ................................................................................... 8‐5
8.4.1 Colorado River Water – Non‐Potable Water (NPW) Deliveries ......................................... 8‐5
8.4.2 Recycled Water Deliveries ................................................................................................. 8‐6
8.4.3 Groundwater Replenishment ............................................................................................ 8‐7
8.5 Water Quality Protection ........................................................................................................... 8‐7
8.5.1 Water Quality Programs and Policies ................................................................................ 8‐8
8.5.2 Coachella Valley Salt and Nutrient Management Plan (CV‐SNMP) ................................... 8‐8
8.6 Current Implementation Status ................................................................................................. 8‐9
9. REFERENCES ....................................................................................................................................... 9‐1
Indio Subbasin Annual Report
for Water Year 2020-21 v TODD / W&C
LIST OF TABLES PAGE
Table ES‐1 WY 2020‐2021 Wells in Water Level Monitoring Program Indio Subbasin ......................... ES‐4 Table ES‐2 WY 2020‐2021 Groundwater Extractions by Water Use Sector in the Indio Subbasin ....... ES‐6 Table 2‐1 Coachella Valley Groundwater Basin Groundwater Storage Capacity .................................. 2‐4 Table 3‐1 WY 2020‐2021 Wells in Water Level Monitoring Program Indio Subbasin ........................... 3‐1 Table 3‐2 SGMA Key Wells ..................................................................................................................... 3‐4 Table 4‐1 WY 2020‐2021 Groundwater Extractions by Water Use Sector in the Indio Subbasin ......... 4‐1 Table 5‐1 WY 2020‐2021 Coachella Valley Precipitation Data (Inches) ................................................. 5‐2 Table 5‐2 WY 2020‐2021 Local Streamflow Measurements for the Indio Subbasin ............................. 5‐4 Table 5‐3 WY 2020‐2021 Direct Use of Local Surface Water in the Indio Subbasin .............................. 5‐6 Table 5‐4 CY 2020 CVWD Colorado River Water Entitlements under the QSA ..................................... 5‐8 Table 5‐5 State Water Project Table A Amounts ................................................................................... 5‐9 Table 5‐6 Deliveries of CVWD and DWA SWP Water to MWD in WY 2020‐2021 ............................... 5‐11 Table 5‐7 WY 2020‐2021 Imported Water for Direct Use in the Indio Subbasin ................................ 5‐12 Table 5‐8 WY 2020‐2021 Recycled Water Use in the Indio Subbasin .................................................. 5‐15 Table 5‐9 WY 2020‐2021 Wastewater Treatment, Reuse, and Disposal in the Indio Subbasin .......... 5‐15 Table 6‐1 WY 2020‐2021 Total Water Use by Sector and Source in the Indio Subbasin ....................... 6‐2 Table 7‐1 WY 2020‐2021 Estimated Average Subsurface Inflows into Indio Subbasin ......................... 7‐3 Table 7‐2 WY 2020‐2021 Measured Drain Flows from the Indio Subbasin to the Salton Sea............... 7‐6 Table 7‐3 WY 2020‐2021 Net Drain Flow from the Indio Subbasin to the Salton Sea ........................... 7‐7 Table 7‐4 WY 2020‐2021 Groundwater Balance in the Indio Subbasin ................................................. 7‐9 Table 8‐2 WY 2020‐2021 CVWMP Implementation Status Update ..................................................... 8‐10
Indio Subbasin Annual Report
for Water Year 2020-21 vi TODD / W&C
LIST OF FIGURES PAGE
Figure ES‐1 Comparison of Supply and Demand for Direct Use for the Indio Subbasin ‐ WY 2020‐2021 ................................................................................................................. ES‐9 Figure ES‐2 Groundwater Balance for the Indio Subbasin – WY 2020‐2021 .................................... ES‐10 Figure 1‐1 Coachella Valley Groundwater Basins and Subbasins ....................................................... 1‐4 Figure 1‐2 Plan Area ............................................................................................................................ 1‐5 Figure 2‐1 Groundwater Subareas of the Indio Subbasin ................................................................... 2‐3 Figure 2‐2 Indio Subbasin Area Geologic Map .................................................................................... 2‐5 Figure 2‐3 Generalized Stratigraphic Column Thermal Subarea ......................................................... 2‐8 Figure 2‐4 Approximate Extent of Shallow Semi‐Perched Aquifer in Thermal Subarea ..................... 2‐9 Figure 3‐1 Elevation Monitoring Well Locations in the Indio Subbasin .............................................. 3‐2 Figure 4‐1 WY 2020‐2021 Groundwater Production .......................................................................... 4‐3 Figure 5‐1 Climate and Streamflow Monitoring Station ..................................................................... 5‐3 Figure 6‐1 Comparison of Supply and Demand for Direct Use for the Indio Subbasin WY 2020‐2021 ................................................................................................................... 6‐3 Figure 7‐1 Groundwater Balance for the Indio Subbasin WY 2020‐2021 ........................................... 7‐2 Figure 7‐2 Historical Annual Change in Groundwater Storage in the Indio Subbasin ...................... 7‐10 Figure 7‐3 Cumulative Change in Groundwater Storage since 1970 ................................................ 7‐12 Figure 7‐4 One‐Year Change in Groundwater Elevation (WY 2018‐2019 ‐ WY 2020‐2021) ............. 7‐13 Figure 7‐5 Ten‐Year Change in Groundwater Elevation (WY 2009‐2010 ‐ WY 2020‐2021) .............. 7‐15
LIST OF APPENDICES
Appendix A Representative Groundwater Elevation Hydrographs Appendix B WY 2020‐2021 Water Use Information for SGMA Portal
Indio Subbasin Annual Report
for Water Year 2020-21 vii TODD / W&C
LIST OF ACRONYMS AND ABBREVIATIONS
˚F degrees Fahrenheit
AB Assembly Bill
AF acre‐feet
AFY acre‐feet per year
AMI Advanced Metering Infrastructure
AOB Area of Benefit
AWAG Agricultural Water Advisory Group
Basin Coachella Valley Groundwater Basin
CASGEM Program California Statewide Groundwater Elevation Monitoring Program CRA Colorado River Aqueduct
CVRWMG Coachella Valley Regional Water Management Group CV‐SNMP Coachella Valley Salt and Nutrient Management Plan CVSC Coachella Valley Stormwater Channel
CVWD Coachella Valley Water District
CVWMP Coachella Valley Water Management Plan
CWA Coachella Water Authority
CWC California Water Code
CWSRF Clean Water State Revolving Fund
CY Calendar Year
DAC Disadvantaged Community
DCF Delta Conveyance Facility
DWA Desert Water Agency
DWR California Department of Water Resources
ECVWSP the East Coachella Valley Water Supply Project
EIR Environmental Impact Report
ET evapotranspiration
EVRA East Valley Reclamation Authority
feet ags feet above ground surface
feet bgs feet below ground surface
feet msl feet above mean sea level
GPS Global Positioning System
GIPSY‐OASIS GNSS‐Inferred Positioning System and Orbit Analysis Simulation Software GRF Groundwater Replenishment Facility
GSA Groundwater Sustainability Agency
GSP Groundwater Sustainability Plan
Indio Subbasin Annual Report
for Water Year 2020-21 viii TODD / W&C
ID Improvement District
IID Imperial Irrigation District
InSAR Interferometric Synthetic Aperture Radar
IPR indirect potable reuse
IWA Indio Water Authority
MCL maximum contaminant level
MC‐GRF Mission Creek Groundwater Replenishment Facility mgd million gallons per day
mi2 square miles
MNM Monitoring Network Module
MP Mile Post
msl mean sea level
MSWD Mission Springs Water District
MT Minimum Threshold
MWD Metropolitan Water District of Southern California MVP Mid‐Valley Pipeline
NAVD88 North American Vertical Datum 1988
NGVD29 National Geodetic Vertical Datum 1929
NPDES National Pollutant Discharge Elimination System NPW non‐potable reuse
PD‐GRF Palm Desert Groundwater Replenishment Facility PMAs project and management actions
QWELL Qualified Water Efficient Landscaper
QSA Quantification Settlement Agreement
RCFCWD Riverside County Flood Control and Water Conservation District SB Senate Bill
SDCWA San Diego County Water Authority
SGMA Sustainable Groundwater Management Act
SNMP Salt and Nutrient Management Plan
sq ft square feet
SWRCB State Water Resources Control Board
SWP State Water Project
TEL‐GRF Thomas E. Levy Groundwater Replenishment Facility USBR United States Bureau of Reclamation
USGS United States Geological Survey
UWMP Urban Water Management Plan
Indio Subbasin Annual Report
for Water Year 2020-21 ix TODD / W&C
VSD Valley Sanitary District
WBIC weather‐based irrigation controller
WRP Water Reclamation Plant
WSCP Water Shortage Contingency Plan
WWR‐GRF Whitewater River Groundwater Replenishment Facility WY Water Year
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-1 TODD / W&C
EXECUTIVE SUMMARY
The Coachella Valley Water District (CVWD), Coachella Water Authority (CWA), Desert Water Agency (DWA), and Indio Water Authority (IWA) represent the Groundwater Sustainability Agencies (GSAs) responsible for sustainably managing the Indio Subbasin in compliance with the Sustainable Groundwater Management Act (SGMA).
On behalf of the Indio Subbasin GSAs, Todd Groundwater and Woodard & Curran have prepared this Indio Subbasin Annual Report for Water Year (WY) 2020-2021 (Annual Report) in accordance with annual reporting requirements of SGMA. The Annual Report summarizes groundwater conditions and the implementation status of projects and management actions in the Indio Subbasin for WY 2020‐2021 (October 1, 2020 to September 30, 2021). This report is the fifth annual report prepared for the Indio Subbasin, which is designated as Basin No. 7‐21.01 by the California Department of Water Resources (DWR).
ES-1 BACKGROUND
The Coachella Valley Groundwater Basin (Basin) has been divided into four Subbasins by DWR as documented in California Bulletin 108 (1964) and Bulletin 118 (2016). The four Subbasins include the Indio 1, Mission Creek, San Gorgonio Pass, and Desert Hot Springs Subbasins (Figure 1-1). The Indio, Mission Creek, and San Gorgonio Pass Subbasins have been designated medium‐priority Subbasins under SGMA, and the Desert Hot Springs Subbasin has been designated a very low‐priority Subbasin.
On December 29, 2016, the Indio Subbasin GSAs submitted to DWR the 2010 Coachella Valley Water Management Plan (CVWMP) (CVWD, 2012a), accompanied by a Bridge Document (Indio Subbasin GSAs, 2016) that describes how the 2010 CVWMP and supporting documents satisfied the requirements of SGMA and should be considered as an acceptable Alternative to a Groundwater Sustainability Plan (GSP) for the Indio Subbasin (Alternative Plan).
On July 17, 2019, DWR approved the Alternative Plan with specific recommendations presented in its Indio Subbasin Alternative Assessment Staff Report and a requirement to submit an Alternative Plan Update by January 1, 2022. Consistent with SGMA, objectives of an Alternative Plan Update were to assess and report progress toward sustainability of the Indio Subbasin, respond to DWR recommendations and, consistent with the goals of the 2010 CVWMP, make needed updates to ensure that future water demands in the Indio Subbasin are reliably met in a cost‐effective and sustainable manner. The Indio Subbasin GSAs published the update to the Alternative Plan, the 2022 Indio Subbasin Water Management Plan Update:
SGMA Alternative Plan (2022 Alternative Plan Update), which was submitted to DWR in December 2021.
The 2022 Alternative Plan Update includes the Indio Subbasin and the areas served by or expected to be served by groundwater from the subbasin (Plan Area).
1 The Indio Subbasin is also identified as the Whitewater River Subbasin by the United States Geological Survey, 1980. However, the Whitewater River Subbasin is identified as the Indio Subbasin in DWR Bulletin 108 (1964) and Bulletin 118 (2016). For consistency with SGMA, this Annual Report will identify the Whitewater River Subbasin as the Indio Subbasin.
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-2 TODD / W&C
ES-2 WY 2020-2021 OVERVIEW
While fifth in the series of Annual Reports, this WY 2020‐2021 Annual Report is the first since submittal of the comprehensive 2022 Alternative Plan Update and incorporates its priorities, findings, and implementation planning. The 2022 Alternative Plan Update is available on the program website ( www.IndioSubbasinSGMA.org) .
The 2022 Alternative Plan Update addressed groundwater sustainability criteria, as defined in SGMA, including the undesirable results of chronic lowering of groundwater levels, reduction of groundwater storage, seawater intrusion, land subsidence, degraded water quality, and depletion of interconnected surface water. SGMA also defines quantitative measures to demonstrate sustainability, which include the Minimum Threshold (MT), a numeric value used to define each undesirable result, and the Measurable Objective (MO), a quantifiable goal to track the performance of sustainable management. The 2022 Alternative Plan Update provided MTs for groundwater levels, defined by historical groundwater low levels (which occurred in the years around 2009). These levels also serve as effective proxy MTs for the potential undesirable results of groundwater storage depletion and subsidence given the direct relationships between groundwater levels and these indicators. Establishment of the MTs also involved identification of 57 Key Wells across the Subbasin to represent local groundwater levels with each Key Well assigned a specific MT.
In WY 2020‐2021, water levels in all 57 wells remained above the MT, confirming that significant undesirable results of chronic lowering of groundwater levels, depletion of groundwater storage, and potential subsidence are not occurring across the basin. While total water use increased relative to WY 2019‐2020, managed artificial recharge continued to replenish the Indio Subbasin, which gained 5,954 AF in storage during WY 2020‐2021. The GSAs continued to implement the Projects and Management Actions (PMAs) detailed in the 2022 Alternative Plan Update; their progress is documented in Section 8.
ES-3 INDIO SUBBASIN SETTING
The Indio Subbasin is a part of the Coachella Valley Groundwater Basin, which extends approximately 50 miles southeast from the San Bernardino Mountains to the northern shore of the Salton Sea (Figure 1-1).
The Coachella Valley Groundwater Basin lies within the northwesterly portion of California's Colorado Desert. The San Bernardino, San Jacinto, and Santa Rosa Mountains impede the eastward movement of storms and create a rain shadow, which results in an arid climate and greatly reduces the contribution of direct precipitation as a source of recharge to groundwater.
The Coachella Valley Groundwater Basin has been divided into four subbasins as described by DWR in Bulletin 108 (1964) and Bulletin 118 (2016). The boundaries between the subbasins are generally defined by faults that impede the lateral movement of groundwater flow.
The Indio Subbasin underlies the major portion of the Coachella Valley floor and encompasses approximately 525 square miles (mi2). As shown on Figure 1-1, it shares a border with the San Gorgonio Pass Subbasin; this boundary represents a bedrock constriction and flow divide. On the southwest, the Indio Subbasin is bordered by the Santa Rosa and San Jacinto Mountains. The Indio Subbasin is separated from the Mission Creek Subbasin by the Banning Fault, and from the Desert Hot Springs Subbasin by the San Andreas Fault; both faults represent effective barriers to groundwater flow (DWR, 1964) (Figure 2-2).
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-3 TODD / W&C
Within the Indio Subbasin, the Garnet Hill Fault also partially impedes groundwater flow from the Garnet Hill Subarea to the south.
Sediments in the northwestern Indio Subbasin are predominantly coarse‐grained. From about the City of Indio southeasterly to the Salton Sea, the Indio Subbasin is characterized by increasingly thick layers of silt and clay, especially in the shallower portions. These silt and clay layers are remnants of ancient lakebed deposits and impede the percolation of water applied for irrigation (DWR 1964). In 1964, DWR estimated that the Indio Subbasin contained approximately 29,800,000 acre‐feet (AF) of water in the first 1,000 feet below the ground surface (feet bgs), or approximately 76 percent of the total groundwater in the Coachella Valley Groundwater Basin.
The Indio Subbasin was divided by DWR (1964) into five subareas: Garnet Hill, Palm Springs, Thermal, Thousand Palms, and Oasis (Figure 2-1). Subareas have been delineated based on one or more of the following geologic or hydrogeologic characteristics: type(s) of water‐bearing formations, water quality, areas of confined groundwater, and groundwater or surface drainage divides. The largest of these are the Palm Springs and Thermal subareas. The Palm Springs Subarea in the northwest is characterized by a thick sequence of coarse sediments and by substantial natural recharge along the Whitewater River and artificial recharge (replenishment). Groundwater from the Palm Springs Subarea moves southeastward through the Thermal Subarea. The Garnet Hill Subarea is located between the Banning and Garnet Hill Faults, which act as barriers to groundwater movement below a depth of about 100 feet bgs. The Garnet Hill Subarea is recharged by subsurface flow from the Mission Creek Subbasin and runoff from the Whitewater River watershed. Relative to the Palm Springs Subarea, the hydrostratigraphy of the Thermal Subarea is generally characterized by greater frequency and extent of fine‐grained sediments that define an Upper Aquifer and Lower Aquifer (separated by a semi‐confining aquitard) and a shallow fine‐grained zone in which semi‐perched groundwater occurs. Semi‐perched groundwater has been maintained by irrigation water applied to agricultural lands, necessitating the construction of an extensive subsurface tile drain system (DWR, 1964). The Thousand Palms Subarea on the southeast margin is characterized by distinct water quality and recharge that apparently occurs mostly from the Indio Hills. Similarly, the Oasis Subarea on the southwest margin is characterized by unconfined groundwater that is different in chemical characteristics from water in the major aquifers of the Indio Subbasin.
ES-4 GROUNDWATER ELEVATION DATA
As summarized in Table ES-1, groundwater levels were measured in 380 wells in WY 2020‐2021. Of these 380 wells, 57 were monitored by the Indio Subbasin GSAs to serve as Key Wells (see Figure 3-1) for assessing sustainability in terms of groundwater levels, storage, and potential subsidence.
As documented in the 2022 Alternative Plan Update, the 57 Key Wells were selected through a quantitative approach that considered wells in terms of long records characteristic of an area and distribution across the Indio Subbasin, Figure 3-1. Each Key Well was assigned a groundwater level MT, based on historical low groundwater levels. Information on these Key Wells and the associated water level data were uploaded to the SGMA portal in December 2021 and will be updated on an on‐going basis.
Groundwater elevations in all 57 of the Key Wells were above the MTs set in the 2022 Alternative Plan Update, showing no indication of chronic lowering of groundwater levels, storage depletion, or potential subsidence.
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-4 TODD / W&C
Table ES-1 WY 2020-2021 Wells in the Indio Subbasin Water Level Monitoring Program Monitoring Agency Key Wells
Monitored
Additional Wells
Monitored
Total Wells
Monitored
Coachella Valley Water District 51 245 296
Coachella Water Authority 1 3 4
Desert Water Agency 4 32 36
Indio Water Authority 1 27 28
Mission Springs Water District 0 2 2
U.S. Geologic Survey 0 14 14
Total 57 323 380
Figure 3-2 shows the WY 2020‐2021 groundwater elevation contour map for the Indio Subbasin.
Groundwater elevations presented in this report are representative of the principal aquifer zone. Average groundwater elevations of the principal aquifer for the water year are used for contouring, as water levels do not exhibit strong seasonal trends. Regional groundwater flows are in a northwest‐to‐southeast direction through the Subbasin. The hydraulic gradients across the Indio Subbasin in WY 2020‐2021 were typically steeper in the northwest, flattening downgradient to the southeast. Groundwater elevations and gradients are strongly influenced by groundwater replenishment activities near the Whitewater River Groundwater Replenishment Facility (WWR‐GRF) and Thomas E. Levy Groundwater Replenishment Facility (TEL‐GRF). Palm Desert Groundwater Replenishment Facility (PD‐GRF) was constructed adjacent to CVWD’s administrative offices in 2019; replenishment activities there do not yet influence hydraulic gradients. Geological faults, constrictions, and pumping also affect localized hydraulic gradients.
Collectively, the hydrographs in Figure 3-2 illustrate the effectiveness of groundwater replenishment, source substitution, and conservation programs under varying historical climatic and water use conditions at reversing historical overdraft. Groundwater levels throughout the Indio Subbasin have either increased or stabilized since historical lows in the early 2000s.
Historically, the eastern portion of the Indio Subbasin experienced artesian conditions with sufficient pressure to cause groundwater levels in wells to rise above the ground surface. Beginning in the late 1980s, groundwater use increased, resulting in declining water levels and the loss of artesian conditions.
Groundwater management programs (including groundwater replenishment, source substitution and water conservation) are restoring groundwater levels and artesian conditions in the eastern portion of the Indio Subbasin. The area of artesian conditions remained relatively stable from WY 2019‐2020 to WY 2020‐2021 (Figure 3-3).
Land subsidence in the Coachella Valley has been investigated since 1995 through an on‐going cooperative program between CVWD and the United States Geological Survey (USGS). Analysis of Interferometric Synthetic Aperture Radar (InSAR) data collected from 1995 to 2017 by the USGS indicates that as much as
2.0 feet of subsidence occurred in the Indio Subbasin from 1995 to 2010 near Palm Desert, Indian Wells, and La Quinta (Sneed and Brandt, 2020). Since 2010, groundwater levels have stabilized or partially recovered in that area in response to the implementation of source substitution, conservation, and groundwater replenishment programs included in the 2010 CVWMP resulting in much smaller subsidence magnitudes. Elsewhere, up to 1 inch of uplift has been measured since 2011 in the Palm Springs area,
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-5 TODD / W&C
corresponding to higher groundwater levels in response to WWR‐GRF recharge. In the Thermal area, the ground surface has also rebounded about 2 inches over the past 10 years, returning to elevations observed in 2001. This rebound coincides with commencement of recharge operations at the TEL‐GRF in 2009.
The Indio Subbasin GSAs plan to continue monitoring water levels and subsidence to track the effects of management actions on land subsidence. The GSAs and the USGS have established a partnership and a continuing subsidence monitoring program to collect and evaluate data between 2015 and 2023 with a report to be published by the USGS by June 30, 2025.
ES-5 GROUNDWATER EXTRACTIONS
A total of 285,351 AF of groundwater was extracted from the Indio Subbasin in WY 2020‐2021 (Table ES-2). The total groundwater extracted represents an increase of 18,597 AF (7 percent) compared to the volume extracted in WY 2019‐2020 (266,754 AF). (local precipitation was below average) or changes in water use patterns due to the COVID‐19 pandemic. The agricultural sector (including fish farms) experienced a volumetric increase in groundwater use of 1,500 AF compared to WY 2019‐2020, or 3.3 percent. The industrial sector experienced a small volumetric decrease in groundwater use of 94 AF compared to WY 2019‐2020, or 6.8 percent. The overall urban usage experienced a volumetric increase in water use (17,191 AF compared to WY 2019‐2020, or 7.9 percent). The increased water use may be due to dry hydrologic conditions in WY 2020‐2021 compared to the wet conditions in WY 2019‐2020. The groundwater use by golf courses and other recreational users is included in the urban sector.
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-6 TODD / W&C
Table ES-2 WY 2020-2021 Groundwater Extractions in the Indio Subbasin by Water Use Sector Water Use
Sector
Groundwater
Extractions
(AF)
Method of
Measurement
Accuracy of
Measurement
Agriculture1 46,561 100% metered ±2%
Industrial2 1,288 15% metered ±2%
85% estimated ±50%
Urban3 236,002 99% metered ±2%
1% estimated ±50%
Undetermined4 1,500 100% estimated ±50%
Total Production 285,351
Notes: `
AF ‐ acre‐feet
AFY ‐ acre‐feet per year
1 – Includes crop irrigation and fish farms.
2 – Includes 1,100 AF of estimated unreported extractions for industrial tribal water use. 3 – Total includes municipal, golf courses and other uses. Total also includes 1,200 AF of estimated unreported extractions for recreational tribal water use. Of the total urban use, 2,187.3 AF is exported for use outside the Indio Subbasin.
4 – Estimated unreported extraction by minimal pumpers (including small water systems, domestic wells, and other private wells) who do not have to report production to CVWD (<25 AFY) or DWA (<10 AFY) and estimated additional unclassified tribal water use.
ES-6 SURFACE WATER
Surface water supplies consist of local surface water, imported Colorado River water from the Coachella Canal, State Water Project (SWP) and other imported supplies exchanged for water from the Colorado River Aqueduct (CRA), and recycled water produced by public wastewater treatment/reclamation plants.
Natural surface water flow in the Coachella Valley occurs as a result of precipitation and concentrated stream runoff originating from the San Bernardino and San Jacinto Mountains, with lesser amounts originating from the Santa Rosa Mountains. Precipitation data for WY 2020‐2021 collected at 12 precipitation monitoring stations in the Coachella Valley are provided in Table 5-1. Station locations are shown on Figure 5-1. The annual precipitation for these stations during WY 2020‐2021 averaged 2.81 inches, or approximately 58 percent relative to the long‐term average.
ES-5.1 Local Surface Water
DWA operates stream diversion facilities on Snow, Falls, and Chino Canyon creeks, and captures subsurface flow from the Whitewater River Canyon. During WY 2020‐2021, 719 AF of local surface water was directly used for urban and agricultural water supply in DWA’s service area as shown in Table 5-3.
Streamflow is measured by the USGS at 19 locations within the Indio Subbasin (Figure 5-1). Table 5-2 shows the station name and number and the recorded streamflow volumes for WY 2020‐2021.
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-7 TODD / W&C
ES-5.2 Colorado River Water
Colorado River water has been a major water supply source for the Indio Subbasin area since the completion of the Coachella Canal in 1949. CVWD is the only agency in the Indio Subbasin that has Colorado River water allocations established in the 2003 Quantification Settlement Agreement. In Calendar Year (CY) 2020, CVWD’s total entitlement of Colorado River water was 399,000 AF, an increase of 5,000 AF as compared to the CY 2019 entitlement. In WY 2020‐2021, approximately 73 percent of the Colorado River water delivered through the Coachella Canal was used for agriculture, about 12 percent was for urban uses (e.g., golf courses and homeowners’ associations), and about 15 percent was replenished at the TEL‐GRF and PD‐GRF.
ES-5.3 State Water Project Water
DWR manages the SWP and determines the available amount of SWP water for delivery based on hydrologic, storage, water rights, water quality, and environmental factors, including requirements for the Sacramento‐San Joaquin Delta. While CVWD and DWA have contracts for Table A SWP water, there are no physical facilities to deliver this water to the Coachella Valley. SWP water is exchanged for Colorado River water from the Metropolitan Water District of Southern California’s (MWD’s) CRA. Since 1973, this exchange water has been delivered for groundwater replenishment to the Indio Subbasin at the WWR‐ GRF and to the Mission Creek Subbasin at the Mission Creek Groundwater Replenishment Facility (MC‐ GRF). An Advance Delivery Agreement between CVWD, DWA, and MWD allows for pre‐delivery of SWP water, exchanged for Colorado River water, in wet years to WWR‐GRF or MC‐GRF. As such, CVWD and DWA may either receive deliveries of SWP exchange water from the CRA or from water previously stored in the Indio Subbasin as part of the Advance Delivery Account.
In WY 2020‐2021, CVWD and DWA received 106,181 AF of SWP and other exchange water at the WWR‐ GRF and 427 AF at the MC‐GRF (in the Mission Creek Subbasin), for a total delivery to the Coachella Valley of 106,608 AF. From this total, 36,925 AF was added to the Advance Delivery Account. At the end of WY 2020‐2021, there was 304,381 AF in MWD’s Advance Delivery Account in the Indio Subbasin.
ES-5.4 Recycled Water
Figure 5-2 shows the locations of water reclamation plants (WRPs) and other wastewater treatment facilities in the Indio Subbasin. Currently, three WRPs provide recycled water for irrigation in the Indio Subbasin (City of Palm Springs WWTP/DWA WRP, CVWD WRP‐7, and CVWD WRP‐10).
Four additional WRPs in the Indio Subbasin treat wastewater, but do not deliver recycled water for direct use (CVWD WRP‐2, CVWD WRP‐4, Coachella WRP, and Valley Sanitary District (VSD) WWTP). For these wastewater treatment facilities, treated effluent is discharged either to onsite percolation/evaporation ponds or to the Coachella Valley Storm Channel (CVSC). In WY 2020‐2021, a total of 40,296 AF of wastewater was treated, of which 14,000 AF was recycled and reused, 4,446 AF was discharged through percolation/evaporation, and 21,849 AF was released to the CVSC.
ES-7 TOTAL WATER USE
A total of 587,632 AF of water was delivered for direct use within the Plan Area during WY 2020‐2021.
This represents an increase of 31,965 AF, or 6 percent, compared to WY 2019‐2020 for the Plan Area, this includes water used in the Subbasin and additional supplies exported for use outside of the groundwater
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-8 TODD / W&C
basin. Over the past three years, water use has been generally consistent despite variations in local weather.
As summarized in Figure ES-1, total direct use is calculated by summing groundwater production, local surface water diversions, Coachella Canal water deliveries, and recycled water use for agricultural, industrial, urban, and other undetermined uses.
Total direct use volumes include 4,876 AF of water exported for use outside of the Indio Subbasin. This includes Colorado River water exported outside the Indio Subbasin for agricultural use (1,117 AF) and urban use (1,572 AF), and groundwater pumped from the Indio Subbasin and delivered outside of the Indio Subbasin (2,187 AF), including groundwater delivered to CVWD customers in Imperial and Riverside counties on the east and west sides of the Salton Sea (East and West Salton Sea Basins) and groundwater pumped by MSWD and delivered to its customers in the Mission Creek Subbasin.
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-9 TODD / W&C
Figure ES-1 Comparison of Supply and Demand for Direct Use for the Plan Area- WY 2020-2021
ES-8 GROUNDWATER BALANCE AND CHANGE IN GROUNDWATER STORAGE A groundwater balance is helpful in assessing the condition of the groundwater of the Indio Subbasin. The groundwater balance compares the inflows to and outflows from the Indio Subbasin for a specific time period. The difference between inflows and outflows at a given time is defined as the change in storage for that time period. The Indio Subbasin groundwater balance for WY 2020‐2021, including estimated inflow and outflow quantities, is summarized on Figure ES-2. The 2022 Alternative Plan Update numerical model was updated through September 2021.
Inflows contributing to the groundwater balance of the Indio Subbasin consist of infiltration of natural runoff, return flows from urban and agricultural uses, artificial replenishment, and Salton Sea intrusion (if any). Inflows from outside the Indio Subbasin consist of subsurface inflow from the San Gorgonio Pass Subbasin and from the Mission Creek and Desert Hot Springs Subbasins. Groundwater outflows from the Indio Subbasin consist of groundwater pumping, flow from the semi‐perched aquifer through agricultural drains into the Salton Sea, evapotranspiration (ET) from the shallow unconfined aquifer, evaporation losses, and subsurface flow out of the Indio Subbasin into the aquifers beneath the Salton Sea.
The annual change in groundwater storage represents the annual difference between inflows and outflows in the Indio Subbasin. During wet years or periods of high artificial recharge, the change in storage is positive (water in storage increases). In dry years, periods of low artificial recharge, or periods of high pumping, the change in storage is often negative (storage decreases). Managed artificial recharge continued to replenish the Subbasin. The Indio Subbasin gained 5,954 AF in storage during WY 2020‐2021.
Total Demand = 587,632 AF
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-10 TODD / W&C
Figure ES-2 Groundwater Balance for the Indio Subbasin – WY 2020-2021
Long‐term sustainability is typically assessed based on changes in groundwater storage over a historical period on the order of 10 to 20 years that includes wet and dry periods. While the goal of the 2010 CVWMP (Alternative Plan) was to eliminate groundwater overdraft, not to restore the Indio Subbasin to historical conditions, it is worth noting that since 2009 the Subbasin has recovered approximately 845,000 AF of groundwater in storage, or about 45 percent of the cumulative depletion observed from 1970 to 2009.
Figure 7-3 shows the cumulative change in storage since 1970. The Indio Subbasin was at its minimum storage in 2009 (with a calculated storage loss of 1,890,000 AF from 1970 to 2009, which represents 6 percent of the estimated storage capacity of the Indio Subbasin). Since 2009, groundwater pumping has decreased by about 25 percent, and replenishment activities have increased, leading to the observed recovery of groundwater in storage. The recovery of groundwater storage demonstrates the progress being made through implementation of the Alternative Plan. Water levels in the Indio Subbasin have generally increased over the past ten years (Figure 7-5), reflecting storage benefits from replenishment operations at all GRFs within the Indio Subbasin and decreased pumping.
Figure 7-4 shows the one‐year change in average groundwater elevations from WY 2019‐2020 to WY 2020‐2021 for the Indio Subbasin. Groundwater levels in the Indio Subbasin generally increased from WY 2019‐2020 to WY 2020‐2021 in most of the Subbasin. However, in the northwestern area of the Subbasin in the immediate vicinity of the WWR‐GRF, groundwater levels declined compared with WY 2019‐2020, due to reduced managed recharge (lower SWP deliveries) in the spring and summer of WY 2020‐2021.
Groundwater levels also declined slightly across the southeast. Increasing groundwater levels up to 11 feet are seen downgradient of the WWR‐GRF in the vicinity of Palm Springs associated with past +5,954 AFY
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-11 TODD / W&C
groundwater replenishment at these facilities. In the central portion of the Indio Subbasin from Palm Desert to La Quinta, groundwater levels generally rose, with water level changes ranging from about ‐3 to
8.5 feet. Some of the increase in groundwater levels is likely associated with the initiation of replenishment at the PD‐GRF beginning in February 2019. In the vicinity of TEL‐GRF, groundwater levels increased by up to 5 feet, with increases observed as far as the Mecca area and adjacent to the Salton Sea. Groundwater level increases reflect the continued benefits of recharge operations at the TEL‐GRF.
Figure 7-5 shows the ten‐year change in average groundwater elevations from WY 2010‐2011 to WY 2020‐ 2021 for the Indio Subbasin. Groundwater levels in most of the Indio Subbasin have increased over the past 10 years. The largest groundwater increases are observed downgradient of the WWR‐GRF in the Palm Springs area and in the vicinity of the TEL‐GRF and PD‐GRF, with water level increases of up to about 70 feet downgradient of the WWR‐GRF, about 43 feet near the TEL‐GRF, and about 26 feet near the PD‐GRF.
In the greater mid‐valley area near Palm Desert, Indian Wells, and La Quinta, groundwater level increases have risen on the order of 20 feet, reflecting the benefits of source substitution, conservation programs, and managed recharge operations. Decreases are seen in the immediate vicinity of the WWR‐GRF where groundwater levels are variable due to large recharge operations, and some localized declines have occurred northeast of Bermuda Dunes. Groundwater levels in the southeastern portion of the Indio Subbasin have generally increased, typically between 10 and 40 feet, reflecting storage benefits from replenishment operations at the TEL‐GRF and decreased pumping.
ES-9 DESCRIPTION OF PROGRESS
The 2022 Alternative Plan Update identified the following water management strategies to achieve water reliability and resilience:
• Fully use available Colorado River water supplies
• Support improvement of the long‐term reliability of SWP supplies, including participation in the Delta Conveyance Facility (DCF)
• Continue developing recycled water as a reliable local water supply • Implement source substitution and replenishment for resilience in response to changing conditions and for maintenance of long‐term groundwater supply reliability • Increase water‐use efficiency across all sectors
• Participate in development of the Coachella Valley Salt and Nutrient Management Plan (CV‐ SNMP) to address salt and nutrient management in the Indio Subbasin.
The Indio Subbasin GSAs are working collaboratively to implement the goals and programs of the 2022 Alternative Plan Update. A variety of projects and management actions (PMAs) are planned for implementation over the planning horizon (to 2045) to achieve sustainability in the Subbasin, summarized in Table 8-1. Thirty PMAs were identified based on priorities identified by the GSAs and stakeholders; these represent a wide variety of activities by the four GSAs. Projects are classified into four categories based on project benefits: water conservation, water supply development, source substitution and replenishment, and water quality protection.
Water conservation is a major component of overall water management in the Indio Subbasin. As a desert community reliant upon imported water supplies, the Coachella Valley has and will continue to use its
Indio Subbasin Annual Report
for Water Year 2020-2021 ES-12 TODD / W&C
water resources efficiently. The Indio Subbasin GSAs are continuing to work with urban and agricultural water purveyors, as well as golf courses, to increase efficiency and reduce future water demands.
CVWD and DWA continue their efforts to increase reliability and obtain additional water supplies, as opportunities become available through SWP‐related projects (e.g., Delta Conveyance Facility, Sites Reservoir, Lake Perris Seepage and other exchanges, entitlements, and transfers).
Source substitution and replenishment is the delivery of an alternate source of water to users that currently pump groundwater, reducing groundwater extraction and allowing the management of groundwater in storage. CVWD is working to expand direct delivery of Colorado River water for agriculture, golf courses, and homeowners’ associations. The Indio Subbasin GSAs are also working to maximize the use of recycled water and expand their non‐potable water systems (some CVWD customers receive a blend of recycled water and Canal water). The 2022 Alternative Plan Update includes non‐ potable water expansions at multiple WRPs in order to reduce the volume of recycled water that is disposed of through onsite percolation basins. CVWD and DWA also intend to continue and expand groundwater replenishment operations with SWP and Canal water in the Indio Subbasin.
PMAs related to water quality that will help protect the groundwater basin for beneficial uses and users and avoid undesirable results include continued implementation of water quality programs and policies in the Subbasin, as well as implementation of the Coachella Valley Salt and Nutrient Management Plan (CV‐SNMP).
Indio Subbasin Annual Report
for Water Year 2020-2021 1-1 TODD / W&C
1. INTRODUCTION
The Coachella Valley Water District (CVWD), Coachella Water Authority (CWA), Desert Water Agency (DWA), and Indio Water Authority (IWA), represent the Groundwater Sustainability Agencies (GSAs) responsible for managing the Indio Subbasin in compliance with the Sustainable Groundwater Management Act (SGMA). On behalf of the Indio Subbasin GSAs, Todd Groundwater and Woodard & Curran have prepared this Indio Subbasin Annual Report for Water Year (WY) 2020-2021 (Annual Report) in accordance with annual reporting requirements of SGMA. The Annual Report summarizes groundwater conditions and the implementation status of projects and management actions in the Indio Subbasin for WY 2020‐2021 (October 1, 2020 to September 30, 2021).
1.1 REPORT ORGANIZATION
This Annual Report is divided into the following nine sections:
Section 1 – Introduction summarizes the report organization, background as related to SGMA, and the approach used by the four Indio Subbasin GSAs to comply with the SGMA.
Section 2 – Groundwater Basin Setting provides an overview of the Coachella Valley Groundwater Basin, its component Subbasins and Subareas, and the physiography, climate, and regional geology of the Indio Subbasin.
Section 3 – Groundwater Elevation Data describes the sources of groundwater level data and provides a groundwater elevation contour map and hydrographs of groundwater levels over time.
Section 4 – Groundwater Extraction summarizes groundwater extraction by volume, area, and water use sectors.
Section 5 – Surface Water summarizes the various surface water sources and surface water‐related components in the Indio Subbasin including precipitation, streamflow, imported water deliveries for direct use and groundwater replenishment, and wastewater treatment, disposal, and reuse.
Section 6 – Total Water Use provides a summary of the total water use by source and water use sector.
Section 7 – Groundwater Balance and Change in Groundwater Storage provides the groundwater balance and change in storage for the Indio Subbasin.
Section 8 – Description of Progress provides a summary of progress toward achieving the water management objectives outlined in the 2022 Indio Subbasin Water Management Plan Update: SGMA Alternative Plan (2022 Alternative Plan Update).
Section 9 – References provides references for this report.
1.2 IMPLEMENTATION OF THE SUSTAINABLE GROUNDWATER MANAGEMENT ACT In 2014, faced with declining groundwater levels (most notably in California’s Central Valley), the California Legislature enacted SGMA to provide a framework for the sustainable management of groundwater resources throughout California, primarily by local authorities. SGMA consisted of three bills, Assembly Bill (AB) 1739 (Dickinson), Senate Bill (SB) 1168 (Pavley), and SB 1319 (Pavley) that were signed into law by Governor Brown on September 16, 2014.
Indio Subbasin Annual Report
for Water Year 2020-2021 1-2 TODD / W&C
For groundwater basins designated by DWR as medium or high‐priority, SGMA required local authorities to form GSAs by June 30, 2017, to evaluate conditions in the groundwater basins, and to prepare and adopt Groundwater Sustainability Plan (GSPs) or Alternative Plans consistent with GSP regulations. The option of an Alternative Plan was provided by SGMA for local water agencies with existing groundwater management plans that could be documented as functionally equivalent to a GSP; the deadline for submittal of Alternative Plans was January 1, 2017. The Indio Subbasin GSAs chose to submit an Alternative Plan, based on decades of local Coachella Valley Groundwater Basin (Basin) management.
SGMA allows a 20‐year time frame for GSAs to implement their GSPs or Alternative Plans and achieve long‐term groundwater sustainability. While protecting existing water rights, SGMA provides GSAs with the tools and authority to:
• Monitor and manage groundwater levels and quality
• Monitor and manage land subsidence and changes in surface water flow and quality affecting groundwater levels or quality or caused by groundwater extraction • Require registration of groundwater wells
• Require reporting of annual extractions
• Require reporting of surface water diversions to underground storage • Impose limits on extractions from individual wells, if needed • Assess fees to implement GSPs and Alternative Plans, and • Request revisions of basin boundaries, including establishing new boundaries.
DWR developed the California Statewide Groundwater Elevation Monitoring (CASGEM) Program to track seasonal and long‐term trends in groundwater elevations in California’s groundwater basins. Through its CASGEM program, DWR ranked all groundwater basins and subbasins in California as either very low, low, medium, or high priority. In addition, DWR, as required by SGMA, identified 21 basins and subbasins in California as critically overdrafted. None of the subbasins in the Coachella Valley Groundwater Basin were listed as high priority or critically overdrafted.
The Coachella Valley Groundwater Basin has been divided into four subbasins by DWR in California Bulletin 108 (1964) and Bulletin 118 (2016): the Indio,2 Mission Creek, San Gorgonio Pass, and Desert Hot Springs Subbasins (Figure 1-1). The Indio, Mission Creek, and San Gorgonio Pass Subbasins were designated medium‐priority under the SGMA, and the Desert Hot Springs Subbasin was designated a very low‐priority Subbasin.
2 The Indio Subbasin is also identified as the Whitewater River Subbasin by the United States Geological Survey (1980). However, the Whitewater River Subbasin is identified as the Indio Subbasin in DWR Bulletin 108 (1964) and Bulletin 118 (2003). For consistency with SGMA, this Annual Report will identify the Whitewater River Subbasin as the Indio Subbasin.
Indio Subbasin Annual Report
for Water Year 2020-2021 1-3 TODD / W&C
1.2.1 Formation of GSAs by Local Agencies in the Indio Subbasin Four separate entities filed Notices of Election with DWR to become GSAs to manage the Indio Subbasin within their respective services areas in compliance with the SGMA:
• Coachella Valley Water District (CVWD)
• Coachella Water Authority (CWA)
• Desert Water Agency (DWA)
• Indio Water Authority (IWA)
These agencies have been designated by DWR as Exclusive GSAs within their respective service areas in the Indio Subbasin and are referred to herein collectively as the Indio Subbasin GSAs. Figure 1-2 shows the jurisdictional areas of the Indio Subbasin GSAs with reference to the Indio Subbasin.
1.2.2 Submission of the Alternative Plan and 2022 Alternative Plan Update SGMA recognized that some groundwater basins, such as the Indio Subbasin, have been managed for years and allowed existing groundwater management plans to be submitted as an Alternative Plan.
Twenty years before the adoption of SGMA, CVWD began development of its initial water management plan to manage available surface water resources and local groundwater resources in the Indio Subbasin and adjacent areas dependent on these water resources. The 2002 Coachella Valley Water Management Plan (CVWMP) and 2010 CVWMP Update were developed to eliminate long‐term overdraft and satisfy the goals and intent of the then‐Groundwater Management Planning Act (now superseded by SGMA).
On December 29, 2016, the Indio Subbasin GSAs collaboratively submitted to DWR the 2010 CVWMP Update (CVWD, 2012a), accompanied by a Bridge Document (Indio Subbasin GSAs, 2016) that describes how the 2010 CVWMP Update and supporting documents satisfy the requirements of SGMA and thus should be considered as an acceptable Alternative Plan for the Indio Subbasin.
The Indio Subbasin Alternative Plan was one of fifteen submitted to DWR by the January 1, 2017 deadline and was one of nine approved by DWR. On July 17, 2019, DWR approved the Indio Subbasin Alternative Plan with specific recommendations presented in its Alternative Assessment Staff Report and a requirement to submit an Alternative Plan Update by January 1, 2022.
Indio Subbasin Annual Report
for Water Year 2020-2021 1-4 TODD / W&C
Figure 1-1 Coachella Valley Groundwater Basins and Subbasins
Indio Subbasin Annual Report
for Water Year 2020-2021 1-5 TODD / W&C
Figure 1-2 Plan Area
Indio Subbasin Annual Report
for Water Year 2020-2021 1-6 TODD / W&C
The 2022 Alternative Plan Update was submitted to DWR on December 29, 2021. Consistent with SGMA, objectives of the 2022 Alternative Plan Update are to assess and report progress toward sustainability of the Indio Subbasin, as well as respond to DWR recommendations. Consistent with the goals of both the 2010 CVWMP Update and the 2022 Alternative Plan Update, the GSAs’ overarching water management goal is to ensure that future water demands in the Indio Subbasin are reliably met in a cost‐effective and sustainable manner.
Additionally, in accordance with SGMA GSP Emergency Regulations (DWR, 2016), DWR requires that the Indio Subbasin GSAs submit annual reports following submission of the Alternative Plan. Annual Reports were therefore submitted in 2018, 2019, 2020 and 2021. This WY 2020‐2021 Annual Report is required to be submitted to DWR by April 1, 2022.
1.2.3 Annual Reporting
CVWD and DWA have reported on groundwater conditions in the Indio Subbasin annually since 1978.
CVWD has published an annual Engineer’s Report on Water Supply and Replenishment Assessment for its West Whitewater River Subbasin Area of Benefit (AOB) since 1980 and for the East Whitewater River Subbasin AOB since 2004. Similarly, DWA has published an Annual Engineer’s Report for the Groundwater Replenishment and Assessment Program in its Whitewater River Subbasin AOB since 1978. The Engineer’s Reports describe groundwater levels, annual water budgets, artificial and natural recharge, and groundwater pumping, as well as the replenishment assessment charged for production within each management area for the following fiscal year.
In accordance with SGMA (Water Code 10728), on April 1 following the year of adoption of a GSP or submission of an Alternative Plan and annually thereafter, the annual report must document the following Basin conditions for the preceding water year:
• Groundwater elevation data
• Aggregated data identifying groundwater extraction
• Surface water supply used or available for groundwater recharge or in‐lieu use • Total water use
• Change in groundwater storage
• Progress toward implementing the GSP or Alternative Plan.
This Indio Subbasin Annual Report for WY 2020‐2021 is the fifth annual report prepared for the Indio Subbasin in response to SGMA requirements and the first prepared following submittal of the 2022 Alternative Plan Update. This Annual Report contains a discussion of the Indio Subbasin followed by sections describing each of the above‐listed elements required by SGMA. Data used to support the development of this Annual Report have been uploaded to DWR’s SGMA Portal. Groundwater elevations of the Key Wells and water use information were uploaded in the format required and included here as Appendix A and Appendix B, respectively.
Indio Subbasin Annual Report
for Water Year 2020-2021 2-1 TODD / W&C
2. INDIO SUBBASIN SETTING
Figure 1-1 shows the extent of the Coachella Valley Groundwater Basin, which encompasses more than 800 square miles and extends from the San Gorgonio Pass area in the San Bernardino Mountains to the northern shore of the Salton Sea. The Basin is bordered by the San Bernardino Mountains on the north, the San Jacinto and Santa Rosa Mountains on the west, the Little San Bernardino Mountains on the east and Salton Sea on the south. The Coachella Valley lies within the northwesterly portion of California's Colorado Desert, an extension of the Sonoran Desert. The San Bernardino, San Jacinto, and Santa Rosa Mountains impede the eastward movement of storms and create a rain shadow, which results in an arid climate and greatly reduces the contribution of direct precipitation as a source of recharge to the Basin.
The Basin is composed of the San Gorgonio Pass, Mission Creek, Desert Hot Springs, and Indio Subbasins (Figure 1). The boundary between the San Gorgonio Pass and Indio Subbasins is a bedrock constriction and divide; otherwise, the boundaries between subbasins within the Basin are generally defined by faults that represent barriers to the lateral movement of groundwater.
The western portion of the Indio Subbasin is characterized by an urban resort/recreation‐based economy and includes the cities of Palm Springs, Cathedral City, Thousand Palms, Rancho Mirage, Palm Desert, and Indian Wells. The eastern portion has a predominantly agricultural‐based economy and includes the cities of Indio, Coachella, and La Quinta, along with the unincorporated communities of Mecca, Thermal, and Oasis.
2.1 CLIMATE
The bulk of natural groundwater replenishment comes in the form of runoff from the adjacent mountains.
Climate in the Indio Subbasin is characterized by low humidity, high summer temperatures, and mild dry winters. Average annual precipitation ranges from 3 to 6 inches on the Valley floor. Most of the precipitation occurs between December and February. Additional discussion of precipitation is provided in Section 5.
Mid‐summer high temperatures commonly exceed 100 degrees Fahrenheit (°F), frequently exceed 110°F, and periodically reach 120°F. Winter high temperatures typically range from about 45°F to 80°F.
2.2 COACHELLA VALLEY GROUNDWATER BASIN
The Coachella Valley Groundwater Basin is bounded by crystalline (non‐water bearing) rocks of the San Bernardino Mountains and Little San Bernardino Mountains to the north/northwest and of the San Jacinto Mountains and Santa Rosa Mountains to the west/southwest. At the west end of the San Gorgonio Pass Subbasin between Beaumont and Banning, a surface drainage divide separates the Coachella Valley Groundwater Basin from the Beaumont Groundwater Basin of the Upper Santa Ana Drainage Area.
The southern boundary is formed primarily by the watershed of the Mecca Hills and by the northwest shoreline of the Salton Sea. At the base of the Santa Rosa Mountains, the southern boundary crosses the Riverside County Line into Imperial and San Diego counties. Although there is subsurface groundwater flow throughout the Basin, fault barriers, constrictions in the groundwater Basin profile, and areas of low permeability limit and control movement of groundwater. Based on the occurrence of these features, the
Indio Subbasin Annual Report
for Water Year 2020-2021 2-2 TODD / W&C
Coachella Valley Groundwater Basin has been divided into subbasins and subareas as described by the DWR in Bulletin 108 (1964) and Bulletin 118 (2016).
Sedimentary infill in the Indio Subbasin consists of thick sand and gravel sedimentary sequences eroded from the surrounding mountains. From about the City of Indio southeasterly to the Salton Sea, the Indio Subbasin is characterized by increasingly thick layers of silt and clay, especially in the shallower portions of the Indio Subbasin. These silt and clay layers are remnants of ancient lakebed deposits and impede the percolation of water applied for irrigation (DWR, 1964).
2.2.1 Subbasins and Subareas of the Coachella Valley Groundwater Basin As shown on Figure 1-1, the Basin is divided into four Subbasins – Indio, San Gorgonio Pass, Mission Creek, and Desert Hot Springs. The subbasins encompass areas underlain by formations that readily yield stored groundwater through water wells and offer natural reservoirs for the management of water supplies. The boundaries between the subbasins are generally defined by faults that impede the lateral movement of groundwater.
Of the four subbasins, the Indio Subbasin is the focus of this Annual Report. The Indio Subbasin has been subdivided into subareas based on one or more of the following geologic or hydrogeologic characteristics:
type(s) of water‐bearing formations, water quality, areas of confined groundwater, and groundwater or surface drainage divides. Boundaries for the Indio Subbasin subareas are shown on Figure 2-1.
The following is a list of the subbasins and associated subareas in the Coachella Valley Groundwater Basin as identified by DWR in Bulletin 108 (1964) and Bulletin 118 (2016), with the subbasin numbers designated by DWR (2016):
• Indio Subbasin (7‐21.01)
o Garnet Hill Subarea
o Palm Springs Subarea
o Thermal Subarea
o Thousand Palms Subarea
o Oasis Subarea
• Mission Creek Subbasin (7‐21.02)
• Desert Hot Springs Subbasin (7‐21.03)
o Miracle Hill Subarea
o Sky Valley Subarea
o Fargo Canyon Subarea
• San Gorgonio Pass Subbasin (7‐21.04)
Section 2.3 provides additional descriptions of Indio Subbasin subareas and boundaries including geology, hydrogeology, water supply, and groundwater storage.
Indio Subbasin Annual Report
for Water Year 2020-2021 2-3 TODD / W&C
Figure 2-1 Groundwater Subareas of the Indio Subbasin
Indio Subbasin Annual Report
for Water Year 2020-2021 2-4 TODD / W&C
2.2.2 Geology
The Indio Subbasin is bounded on its northern, northwestern, southwestern, and southern margins by uplifted bedrock; Indio Subbasin sedimentary fill consists of thick sand and gravel sedimentary sequences eroded from the surrounding mountains. Sedimentary infill within the Indio Subbasin thickens from north to south, and depending on location within the Basin, is at least several thousand and as much as 12,000 feet thick. The upper approximately 2,000 feet constitute the aquifer system that is the primary source of groundwater supply (DWR, 1979). Figure 2-2 is a geologic map encompassing the Indio Subbasin.
From about the City of Indio southeasterly to the Salton Sea, the Indio Subbasin is characterized by increasingly thick layers of silt and clay, especially in the shallower portions of the Indio Subbasin. These silt and clay layers are remnants of ancient lakebed deposits and impede the percolation of water applied for irrigation (DWR 1964).
2.2.3 Basin Storage Capacity
In 1964, DWR estimated that the Subbasins in the Coachella Valley Groundwater Basin contained approximately 39,200,000 acre‐feet (AF) of water in the first 1,000 feet bgs, of which 29,800,000 AF is in the Indio Subbasin. The capacities of the Indio Subbasin subareas are shown in Table 2-1.
Table 2-1 Indio Subbasin Groundwater Storage Capacity
Subarea Groundwater Storage (AF)1
Garnet Hill Subarea 1,000,000
Oasis Subarea 3,000,000
Palm Springs Subarea 4,600,000
Thermal Subarea 19,400,000
Thousand Palms Subarea 1,800,000
Indio Subbasin Total 29,800,000
Notes:
AF ‐ acre‐feet
1 – Storage volume in first 1,000 feet below the ground surface (DWR, 1964).
2.3 INDIO SUBBASIN DESCRIPTION
The Indio Subbasin underlies the major portion of the Coachella Valley floor and encompasses approximately 525 square miles (mi2). The Indio Subbasin extends from the Whitewater area in the northwest approximately 50 miles to the southeast, terminating along the northern shoreline of the Salton Sea.
Indio Subbasin Annual Report
for Water Year 2020-2021 2-5 TODD / W&C
Figure 2-2 Indio Subbasin Area Geologic Map
Indio Subbasin Annual Report
for Water Year 2020-2021 2-6 TODD / W&C
The Indio Subbasin is bordered on the southwest by the Santa Rosa and San Jacinto Mountains and is separated from the Mission Creek Subbasin by the Banning Fault, and from the Desert Hot Springs Subbasin by the San Andreas Fault; both faults represent effective barriers to groundwater flow (DWR, 1964) (Figure 2-2). The San Andreas Fault extends southeasterly from the junction of the Mission Creek and Banning Faults in the Indio Hills and continuing out of the Basin on the east flank of the Salton Sea.
The boundaries between subbasins within the Basin are generally defined by other faults that serve as effective barriers to the lateral movement of groundwater.
Within the Indio Subbasin, the Garnet Hill Fault extends southeasterly from the north side of the San Gorgonio Pass to the Indio Hills. The Garnet Hill Subarea lies between the Garnet Hill and Banning faults, which act as partially effective barriers to lateral groundwater movement. The Garnet Hill Fault partially impedes groundwater flow from the Garnet Hill Subarea toward the south. This effect is revealed by close inspection of groundwater level information on either side of the Garnet Hill Fault; for example, the groundwater level contour map in the Indio Subbasin Annual Report for Water Year 2018-2019 shows differences of as much as 220 feet across the Garnet Hill Fault. The Garnet Hill Fault does not reach the surface and is probably effective as a barrier to lateral groundwater movement only below a depth of about 100 feet (CVWD, DWA, and MSWD, 2013).
Figure 2-1 shows the five Indio Subbasin subareas: Garnet Hill, Palm Springs, Thermal, Thousand Palms, and Oasis. The Palm Springs Subarea is the forebay or main area of replenishment to the Indio Subbasin, and the Thermal Subarea includes the pressure, or confined area, within the Indio Subbasin. The other three subareas are characterized by unconfined groundwater conditions.
2.3.1 Garnet Hill Subarea
The Garnet Hill Subarea, located between the Garnet Hill Fault and the Banning Fault, is considered part of the Indio Subbasin as defined in DWR's California’s Groundwater: Bulletin 118—Update 2003 (Bulletin 118) (DWR, 2003) as shown in Figure 2-1. The relative scarcity of wells in the subarea limits the available geologic information and understanding of groundwater interactions between this subarea and the adjoining Mission Creek Subbasin and Indio Subbasin. Groundwater production is relatively low in the Garnet Hill Subarea and is not expected to increase significantly in the future due to relatively low well yields compared to those in the Mission Creek Subbasin. Groundwater levels in the western and central portions of the Garnet Hill Subarea show response to large replenishment quantities from the WWR‐GRF, while levels are relatively flat in the eastern portion of the subarea.
While the Garnet Hill Subarea receives subsurface inflow from the Mission Creek Subbasin and some natural recharge from occasional high flows of Mission Creek and other streams, the chemical character of the groundwater and its direction of movement indicate that the main source of inflow to the subarea comes from percolation associated with the Whitewater River (CVWD, DWA, and MSWD, 2013).
2.3.2 Palm Springs Subarea
Located in the northwestern portion of the Indio Subbasin, the Palm Springs Subarea is bounded by the Garnet Hill Fault to the north and the eastern slopes of the San Jacinto Mountains to the south and extends southeast to Cathedral City. Alluvial fan deposits consist of heterogeneous, coarse‐grained sediments with a total thickness in excess of 1,000 feet. Although no lithologic distinction is apparent from water well driller’s logs, the total thickness of recent deposits suggests that Ocotillo Conglomerate underlies recent Fanglomerate deposits at a depth ranging from 300 to 400 feet (DWR, 1964). Substantial natural and
Indio Subbasin Annual Report
for Water Year 2020-2021 2-7 TODD / W&C
artificial recharge (i.e., replenishment) occurs through the thick sequence of coarse sediments in this subarea.
2.3.3 Thermal Subarea
Groundwater in the Palm Springs Subarea moves southeastward into the Thermal Subarea. As shown in Figure 2-1, the division between the Palm Springs Subarea and the Thermal Subarea is near the City of Cathedral City.
Figure 2-3 presents a generalized stratigraphic column of the Thermal Subarea showing local geologic units and groundwater zones. As illustrated, the hydrostratigraphy is characterized by the following:
• A shallow semi‐perched and confining zone consisting of recent silts, clays, and fine sands • An upper aquifer with unconfined (water table) conditions • A semi‐confining aquitard of fine‐grained materials
• A lower aquifer with confined and artesian conditions As shown on Figure 2-3, fine‐grained (clay) deposits of the upper Ocotillo Conglomerate Formation separate the upper and lower aquifers. The clay deposits are not regionally extensive or thick enough to completely restrict vertical groundwater flow between the upper and lower aquifer zones and are thus referred to as an aquitard.
The aquitard is absent (and no distinction between the upper and lower aquifer zones occurs) along the southwestern margins of the Thermal Subarea at the base of the Santa Rosa Mountains, such as the alluvial fans at the mouth of Deep Canyon and near the City of La Quinta.
The lower aquifer, composed of Ocotillo Conglomerate Formation, consists of silty sands and gravels with interbeds of silt and clay. The lower aquifer contains the greatest quantity of stored groundwater in the Indio Subbasin. The top of the lower aquifer occurs at a depth ranging from 300 to 600 feet bgs. The thickness of the zone is undetermined, as the deepest wells in the Coachella Valley do not fully penetrate the formation. Available data indicate the zone is at least 500 feet thick and can be in excess of 1,000 feet thick. The thickness of the aquitard overlying the lower aquifer zone ranges from 100 to 200 feet, although in some areas near the Salton Sea it may be in excess of 500 feet.
Capping the upper aquifer zone in the Thermal Subarea is a shallow fine‐grained zone in which semi‐ perched groundwater occurs (Figure 2-4). This zone consists of recent silts, clays, and fine sands and is relatively persistent southeast of the City of Indio. It ranges from 0 to 100 feet thick and is an effective barrier to deep percolation. The low permeability of the materials southeast of the City of Indio has contributed to irrigation drainage challenges in the area. Semi‐perched groundwater has been maintained by irrigation water applied to agricultural lands, necessitating the construction of an extensive subsurface tile drain system (DWR, 1964). North and west of the City of Indio, the zone is composed mainly of clayey sands and silts, and its effect in retarding deep percolation is limited.
Indio Subbasin Annual Report
for Water Year 2020-2021 2-8 TODD / W&C
Figure 2-3 Generalized Stratigraphic Column Thermal Subarea
Indio Subbasin Annual Report
for Water Year 2020-2021 2-9 TODD / W&C
Figure 2-4 Approximate Extent of Shallow Semi-Perched Aquifer in Thermal Subarea
Indio Subbasin Annual Report
for Water Year 2020-2021 2-10 TODD / W&C
2.3.4 Thousand Palms Subarea
The Thousand Palms Subarea (Figure 2-1) is located along the southwest flank of the Indio Hills and is differentiated from the Thermal Subarea by groundwater quality differences (DWR, 1964). In brief, groundwater in the Thousand Palms Subarea is characterized by sodium sulfate chemistry that is distinct from the calcium bicarbonate water of the Thermal Subarea. The differences in water quality indicate that replenishment to the Thousand Palms Subarea comes primarily from the Indio Hills and is limited in supply. The relatively sharp boundary between chemical characteristics of water derived from the Indio Hills in the Thousand Palms Subarea and groundwater in the Thermal Subarea suggests there is little intermixing between the two subareas.
The configuration of the water table north of the community of Thousand Palms is such that the generally uniform, southeasterly gradient in the Palm Springs Subarea diverges and steepens to the east along the base of Edom Hill. This steepened gradient suggests the presence of a barrier to groundwater flow in the form of a reduction in sediment permeability or a southeast extension of the Garnet Hill Fault. Gravity surveys by DWR (1964) do not indicate a subsurface fault. Accordingly, the sharp increase in gradient is attributed to lower sediment permeability to the east.
2.3.5 Oasis Subarea
Another peripheral zone of unconfined groundwater, with different chemical characteristics from water in the major Indio Subbasin areas, is found underlying the Oasis Subarea that extends along the base of the Santa Rosa Mountains. Water‐bearing materials underlying the subarea consist of highly permeable alluvial fan deposits. Although groundwater data suggest that the boundary between the Oasis and Thermal subareas may be a buried fault extending from Travertine Rock to the community of Oasis, the remainder of the boundary is a lithologic change from the coarse fan deposits of the Oasis Subarea to the interbedded sands, gravel, and silts of the Thermal Subarea. Little information is available as to the thickness of the water‐bearing materials, but it is estimated to be in excess of 1,000 feet.
Indio Subbasin Annual Report
for Water Year 2020-2021 3-1 TODD / W&C
3. GROUNDWATER ELEVATION DATA
This section summarizes groundwater conditions in terms of elevations, flow, trends over time, and artesian conditions.
3.1 MONITORING WELLS
Groundwater level monitoring data are available for selected wells in the Indio Subbasin dating back to 1910. As summarized in Table 3-1, Indio Subbasin groundwater levels were measured in 380 wells in WY 2020‐2021, including 366 wells monitored by the Indio Subbasin GSAs and Mission Springs Water District (MSWD) and 14 monitored by the USGS. Of the 366 wells monitored by the GSAs and MSWD, 57 Key Wells were monitored as part of the SGMA monitoring program and their data were uploaded to Monitoring Network Module (MNM) on the DWR’s SGMA Portal.
Table 3-1 WY 2020-2021 Wells in the Indio Subbasin Water Level Monitoring Program Monitoring Agency Key Wells
Monitored
Additional Wells
Monitored
Total Wells
Monitored
Coachella Valley Water District 51 245 296
Coachella Water Authority 1 3 4
Desert Water Agency 4 32 36
Indio Water Authority 1 27 28
Mission Springs Water District 0 2 2
U.S. Geologic Survey 0 14 14
Total 57 323 380
Notes:
Mission Springs Water District has SGMA key wells in the Mission Creek Subbasin
Previously, water agencies uploaded data for select wells to the California Statewide Groundwater Elevation Monitoring (CASGEM) program. As Indio Subbasin has an approved Alternative Plan, GSAs will now meet the monitoring requirements using the MNM on the SGMA Portal. Indio Subbasin GSAs submitted monitoring data for the SGMA Key Wells to the Monitoring Network Module (MNM) in December 2021 and will continue to update it with seasonal monitoring data. The GSAs will no longer upload data to CASGEM for basins covered by Alternative Plans.
The groundwater elevation monitoring data are used to characterize Subbasin conditions, evaluate pumping and recharge operations, assess minimum thresholds for SGMA indicators, and support groundwater modeling and model calibration. Figure 3-1 illustrates the distribution of groundwater elevation monitoring wells in the Indio Subbasin monitored by agencies. The 57 Key Wells selected to track SGMA progress are highlighted in green on Figure 3-1.
Indio Subbasin Annual Report
for Water Year 2020-2021 3-2 TODD / W&C
Figure 3-1 Elevation Monitoring Well Locations in the Indio Subbasin
Indio Subbasin Annual Report
for Water Year 2020-2021 3-3 TODD / W&C
3.2 KEY WELLS
As part of the 2022 Alternative Plan Update, the GSAs took the general approach to defining sustainability criteria based on recognition of the following: 1) historical low groundwater levels have occurred relatively recently in the Indio Subbasin and 2) there has been an absence of reported problems associated with those historical lows. Accordingly, it is reasonable to assume that maintaining groundwater elevations at or above minimum historical values should not cause undesirable results. This has been substantiated by a review of available information on the location and depths of wells serving both municipal and small water systems, which indicated that historical low groundwater levels were above the shallowest well depths.
The 2022 Alternative Plan Update identified a network of 57 Key Wells, shown on Figure 3-1. These Key Wells were selected through a quantitative approach that considered the wells with long records characteristic of an area and distribution of wells across the Indio Subbasin. These wells are representative of local groundwater elevation conditions and are appropriate for inclusion in the Key Well groundwater elevation monitoring network (a subset of the overall monitoring program). Each Key Well was assigned a Minimum Threshold (MT) for groundwater levels, recognizing that chronic lowering of groundwater levels can indicate significant and unreasonable depletion of supply, causing undesirable results to domestic, agricultural, municipal, and other beneficial uses of groundwater.
The MT for chronic lowering of groundwater levels is defined at each Key Well by historical low groundwater levels. Undesirable results are indicated when groundwater levels are below the MT for five consecutive same season monitoring events, in 25 percent or more of the Key Wells in the Indio Subbasin.
Consistent with SGMA, Measurable Objectives (MOs) are specific, quantifiable goals to track management performance relative to sustainability indicators. In the 2022 Alternative Plan Update, the GSAs define the MOs as maintaining groundwater levels above the groundwater level MTs and within an operating range; this represents a sustainable groundwater system. In addition, the 2022 Alternative Plan Update demonstrated that the groundwater level MTs are appropriate proxy criteria for other sustainability indicators including groundwater storage and subsidence, given that groundwater levels are linked to these indicators.
Key Wells, their MTs, and WY 2020 – 2021 minimum groundwater levels are listed in Table 3-2. These wells and associated level data were uploaded to the MNM of the SGMA Portal with submittal of this Annual Report. For elevations, CVWD uses the National Geodetic Vertical Datum (NGVD) NGVD29 and MTs for each well were determined in this datum for the 2022 Alternative Plan Update. DWA has surveyed their key wells and reference point elevations are available in the North American Vertical Datum (NAVD) NAVD88. The datum used for the other GSAs was unknown but assumed to be NGVD29, pending verification. DWR requires all elevation data be submitted in the MNM using the NAVD88 datum. For transparency, both datums are shown in Table 3-2. A figure showing key well locations and numbers (Figure A-1), hydrographs and the respective MTs for each Key Well in the NAVD88 datum are included as Appendix A.
Indio Subbasin Annual Report
for Water Year 2020-2021 3-4 TODD / W&C
Table 3-2 SGMA Key Wells
Key
Well
Number
SWN Well Name/Owner First Year
Monitored
MT
NGVD
29 MT
NAVD
88 Minimum
GW
Elevation
WY 20-21
NAVD88
Season
Min GW
Elevation
Occurred
Above
MT
KW_001 03S04E17K01S Private Well 1954 617.0 617.8 669.9 Fall Yes KW_002 03S04E22A01S Private Well 1953 586.4 587.2 610.3 Fall Yes KW_003 03S04E34R01S DWA WELL 21 1973 242.6 243.3 339.7 Spring Yes KW_004 03S05E30G01S Private Well 1965 379.9 380.6 385.7 Fall Yes KW_005 04S04E13C01S DWA WELL 23 1975 184.1 184.9 251.9 Spring Yes KW_006 04S04E24D01S DWA WELL 24 1978 164.3 165.0 223.1 Spring Yes KW_007 04S05E09B01S CVWD Well 4562‐1 1962 151.4 152.2 204.8 Spring Yes KW_008 04S05E15R02S Private Well 1960 99.0 99.7 140.4 Spring Yes KW_009 04S05E17Q02S DWA WELL 31 1987 134.5 135.3 183.5 Spring Yes KW_010 04S05E28F02S CVWD Well 4519‐1 1974 105.4 106.2 136.1 Fall Yes KW_011 04S05E29F01S Private Well 1958 129.3 130.1 167.8 Spring Yes KW_012 04S05E35G03S CVWD Well 4503‐1 1953 55.1 55.9 79.0 Spring Yes KW_013 04S06E18R01S CVWD Well 4623‐1 1953 33.7 34.4 53.0 Spring Yes KW_014 04S06E20M02S CVWD Well 4628‐2 2003 15.4 16.1 37.6 Spring Yes KW_015 04S06E32N02S CVWD Well 4611‐1 2000 ‐102.6 ‐101.9 ‐83.7 Spring Yes KW_016 04S06E35P01S Private Well 1985 ‐45.4 ‐44.7 ‐27.2 Spring Yes KW_017 05S05E12H02S CVWD Well 5507‐1 1956 4.6 5.4 21.6 Spring Yes KW_018 05S06E12N01S CVWD Well 5626‐1 1980 ‐65.1 ‐64.4 ‐44.9 Fall Yes KW_019 05S06E16A02S CVWD Well 5620‐1 1976 ‐42.0 ‐41.3 ‐17.4 Spring Yes KW_020 05S06E24G01S CVWD Well 5636‐1 1965 ‐86.7 ‐86.0 ‐62.8 Spring Yes KW_021 05S06E29C01S CVWD Well 5643‐1 1956 ‐37.0 ‐36.2 ‐14.1 Fall Yes KW_022 05S07E04A01S
CVWD Well WRP7
MW‐1 Dave Price 1955 ‐62.6 ‐61.9 ‐60.9 Fall Yes
KW_023 05S07E06B04S CVWD Well 5720‐1 1993 ‐77.0 ‐76.3 ‐61.3 Fall Yes KW_024 05S07E08Q01S Private Well 1967 ‐79.4 ‐78.7 ‐68.1 Spring Yes KW_025 05S07E24M04S IWA WELL 1C 1985 ‐92.1 ‐91.4 ‐86.3 Spring Yes KW_026 05S07E27L01S Private Well 1965 ‐142.0 ‐141.3 ‐121.6 Fall Yes KW_027 05S07E28E01S CVWD Well 5701‐1 1948 ‐95.5 ‐94.8 ‐89.3 Fall Yes KW_028 05S07E31P01S CVWD Well 5706‐1 1978 ‐107.6 ‐106.9 ‐103.1 Fall Yes KW_029 05S07E32B01S CVWD Well 5725‐1 2005 ‐155.2 ‐154.5 ‐124.4 Fall Yes KW_030 05S08E33D01S CWA 10 1979 ‐160.7 ‐160.0 ‐87.4 Fall Yes KW_031 06S07E02D02S Private Well 1985 ‐157.2 ‐156.5 ‐80.7 Fall Yes KW_032 06S07E06B01S CVWD Well 6701‐1 1981 ‐145.4 ‐144.7 ‐115.7 Fall Yes KW_033 06S07E13M02S CVWD Well 6781‐1 1963 ‐91.4 ‐90.7 ‐88.9 Fall Yes
Indio Subbasin Annual Report
for Water Year 2020-2021 3-5 TODD / W&C
Key
Well
Number
SWN Well Name/Owner First Year
Monitored
MT
NGVD
29 MT
NAVD
88 Minimum
GW
Elevation
WY 20-21
Season
Min GW
Elevation
Occurred
Above
MT
KW_034 06S07E16A02S CVWD Well 6723‐1 1987 ‐172.7 ‐172.0 ‐126.5 Fall Yes KW_035 06S07E23F01S Private Well 1965 ‐163.2 ‐162.5 ‐126.2 Fall Yes KW_036 06S07E29B01S Private Well 1995 ‐170.9 ‐170.2 ‐89.3 Fall Yes KW_037 06S07E35L02S Private Well 1988 ‐176.6 ‐175.9 ‐80.6 Spring Yes KW_038 06S08E05R02S CVWD Well 6858‐1 1957 ‐103.4 ‐102.7 ‐100.1 Fall Yes KW_039 06S08E12Q01S Private Well 1991 ‐132.7 ‐132.0 ‐109.3 Fall Yes KW_040 06S08E22D02S CVWD Well 6803‐1 1966 ‐177.1 ‐176.4 ‐140.4 Fall Yes KW_041 06S08E25Q01S Private Well 1979 ‐188.4 ‐187.7 ‐153.0 Spring Yes KW_042 06S08E31P01S Private Well 1989 ‐184.8 ‐184.1 ‐132.7 Spring Yes KW_043 06S09E32Q01S Private Well 1966 ‐176.0 ‐175.3 ‐135.7 Spring Yes KW_044 07S07E02G02S Private Well 1996 ‐178.2 ‐177.5 ‐96.6 Spring Yes KW_045 07S08E10P01S Private Well 1988 ‐204.2 ‐203.5 ‐158.7 Spring Yes KW_046 07S08E17G01S CVWD Well 7801‐1 1972 ‐197.3 ‐196.6 ‐148.7 Spring Yes KW_047 07S08E33B01S Private Well 1965 ‐211.4 ‐210.7 ‐166.1 Spring Yes KW_048 07S09E07J01S CVWD Well 7993‐1 1970 ‐245.9 ‐245.2 ‐175.5 Fall Yes KW_049 07S09E14C01S Private Well 1992 ‐180.6 ‐179.9 ‐155.0 Spring Yes KW_050 07S09E16M03S Private Well 1989 ‐261.5 ‐260.8 ‐192.0 Spring Yes KW_051 07S09E18H01S Private Well 1994 ‐263.1 ‐262.4 ‐191.7 Spring Yes KW_052 07S09E30R01S CVWD Bernadine 1996 ‐209.1 ‐208.4 ‐174.8 Fall Yes KW_053 08S08E03L01S Private Well 1965 ‐220.2 ‐219.5 ‐174.3 Spring Yes KW_054 08S08E24L01S Private Well 1939 ‐257.1 ‐256.4 ‐209.0 Fall Yes KW_055 08S09E07N03S CVWD Gracie 2003 ‐249.6 ‐248.9 ‐197.5 Fall Yes KW_056 08S09E30A01S Private Well 1965 ‐266.5 ‐265.8 ‐219.3 Fall Yes KW_057 08S09E33N01S Private Well 1952 ‐262.9 ‐262.2 ‐216.2 Spring Yes Notes:
MT ‐ Minimum Threshold
NGVD29 ‐ National Geodetic Vertical Datum 1929
NAVD88 ‐ North American Vertical Datum 1988
DWA ‐ Desert Water Agency
CVWD ‐ Coachella Valley Water District
SWN ‐ State Well Number
Spring is defined Jan ‐ Jun and Fall July ‐ Dec
Indio Subbasin Annual Report
for Water Year 2020-2021 3-6 TODD / W&C
Figure 3-2 Indio Subbasin Groundwater Elevation Contours WY 2020-2021
Indio Subbasin Annual Report
for Water Year 2020-2021 3-7 TODD / W&C
3.3 GROUNDWATER ELEVATIONS, FLOW, AND TRENDS
Figure 3-2 shows the WY 2020‐2021 groundwater elevation contour map for the Indio Subbasin. Average groundwater elevations of the principal aquifer for the water year are used for contouring, as water levels do not exhibit strong seasonal trends. Regional groundwater flows are in a northwest‐to‐southeast direction through the Indio Subbasin. Groundwater elevations range from greater than 1,200 feet above mean sea level (feet msl) near the San Gorgonio Pass Subbasin in the northwest to approximately ‐200 feet msl in the southeast along the northern shoreline of the Salton Sea. The hydraulic gradients across the Indio Subbasin in WY 2020‐2021 were typically steeper in the northwest with the gradient flattening to the southeast. Groundwater elevations and gradients are strongly influenced by groundwater replenishment activities near the WWR‐GRF and TEL‐GRF. Geological faults, constrictions, and pumping also affect local hydraulic gradients.
Long‐term water level hydrographs for 16 selected Key Wells distributed across the Indio Subbasin are presented on Figure 3-2 to illustrate groundwater elevation trends over time. Water level measurements for the 16 wells are included on five hydrographs labeled 1 through 5 on Figure 3-2 and depict the groundwater level response to historical pumping and water management activities in the Indio Subbasin.
The hydrographs show that groundwater levels in the northwestern portion of the Indio Subbasin have responded directly and positively to historical replenishment activities at the WWR‐GRF (Hydrograph 1).
Groundwater elevations in the Palm Springs/Cathedral City area have remained relatively stable over time with more moderate positive responses to upgradient WWR‐GRF replenishment activities. Groundwater levels in the Palm Desert area have stabilized since 2005 and increased slightly since 2010 with recent increases coinciding with reduced groundwater pumping and initiation of recharge at the PD‐GRF in February 2019 (Hydrograph 2). Groundwater elevations in Bermuda Dunes, La Quinta, Indio, and Coachella have stabilized since 2005 and increased slightly in the La Quinta area since 2010 (Hydrograph 3). Groundwater elevations in the southeastern portion of the Indio Subbasin near Thermal and Mecca have responded positively to replenishment activities at the TEL‐GRF since recharge commenced in 2009 (Hydrographs 4 and 5). Full‐scale hydrographs for all Key Wells are provided in Appendix A. The full‐scale hydrographs in Appendix A show the surface elevation of each well as a horizontal line.
Collectively, the selected hydrographs illustrate the effectiveness of groundwater replenishment, source substitution, and conservation programs in the Indio Subbasin in maintaining and, in some areas, increasing groundwater storage under varying historical climatic and water use conditions.
3.3.1 Artesian Conditions
Historically, the eastern portion of the Indio Subbasin experienced artesian conditions with sufficient pressure to cause groundwater levels in wells to rise above the ground surface. Artesian flowing wells attracted early settlers to farm in this area, but subsequently declined in the late 1930s due to increased local groundwater pumping. The completion of the Coachella Canal by the United States Bureau of Reclamation (USBR) in 1949 brought Colorado River water to the eastern Coachella Valley for agricultural irrigation purposes. Artesian conditions returned in the early 1960s through the 1980s, as imported Colorado River water was substituted for groundwater production. Beginning in the late 1980s, groundwater use increased again, resulting in declining water levels and the loss of artesian conditions.
The GSAs’ water management programs, including groundwater replenishment, source substitution and water conservation, are restoring local groundwater levels and artesian conditions have returned in the
Indio Subbasin Annual Report
for Water Year 2020-2021 3-8 TODD / W&C
eastern Indio Subbasin. Benefits associated with artesian conditions include reduced groundwater pumping costs and water quality protection of the deeper, confined production zone aquifers.
Figure 3-3 shows the location of 15 wells under artesian pressure in WY 2020‐2021 and their respective water pressure equivalent elevation (measured in feet above ground surface [feet ags]). The area of artesian conditions remained relatively stable in comparison to WY 2019‐2020. The table on the figure compares groundwater elevations between WY 2019‐2020 and WY 2020‐2021 for 13 wells that consistently show artesian conditions. Increases in artesian water levels (ranging from +0.53 to +7.33 feet) are noted in 8 of the 13 artesian wells. The other five wells showed decreases of up to 2.9 feet.
Indio Subbasin Annual Report
for Water Year 2020-2021 3-9 TODD / W&C
Figure 3-3 WY 2020-2021 Artesian Wells in the Indio Subbasin
Indio Subbasin Annual Report
for Water Year 2020-2021 3-10 TODD / W&C
3.4 LAND SUBSIDENCE
Land subsidence is the differential lowering of the ground surface, which can damage structures and facilities. This may be caused by regional tectonism or by declines in groundwater elevations due to pumping. Land subsidence, resulting from aquifer system compaction and groundwater level declines, has been a concern in the Coachella Valley since the mid‐1990s and has been investigated since 1996 through an on‐going cooperative program between CVWD and the USGS (Sneed and Brandt, 2020). Global Positioning System (GPS) surveying, using GNSS‐Inferred Positioning System and Orbit Analysis Simulation Software (GIPSY‐OASIS) and interferometric synthetic aperture radar (InSAR) methods, have been used to determine the location, extent, and magnitude of the vertical land‐surface changes in the Coachella Valley.
The GPS measurements have been used to determine elevation changes at specific locations, while InSAR measurements have documented the geographic extent of elevation changes for the Indio Subbasin.
Analysis of InSAR data collected from 1995 to 2017 by the USGS indicates that as much as 2.0 feet of subsidence occurred in the Indio Subbasin from 1995 to 2010 near Palm Desert, Indian Wells, and La Quinta (Sneed and Brandt, 2020).
Since 2010, groundwater levels have stabilized or have partially recovered in response to the implementation of source substitution, conservation, and groundwater replenishment programs. Up to one inch of uplift has been measured since 2011 in the Palm Springs area, corresponding to higher groundwater levels in response to upgradient WWR‐GRF recharge. In the Thermal area, the ground surface has also rebounded about two inches over the past 10 years, returning to elevations observed in 2001. This rebound roughly coincides with commencement of recharge operations at the TEL‐GRF in 2009.
The Indio Subbasin GSAs plan to continue monitoring water levels and subsidence to track the effects of management actions on land subsidence. The GSAs and the USGS have established a partnership and a continuing subsidence monitoring program to collect and evaluate data between 2015 and 2023 with a report to be published by the USGS before June 30, 2025 (CVWD, et al., 2021b).
Groundwater level MTs are used as a proxy to monitor subsidence. Table 3-2 indicates that all Key Wells are above their MTs.
Indio Subbasin Annual Report
for Water Year 2020-2021 4-1 TODD / W&C
4. GROUNDWATER EXTRACTIONS
This section presents groundwater extraction volumes for the Indio Subbasin for WY 2020‐2021. Because CVWD and DWA are authorized to collect a replenishment assessment fee from groundwater producers, their respective governing policies mandate the installation of water meters on all wells owned by entities producing more than 25 acre‐feet per year (AFY) in CVWD’s service area and more than 10 AFY in DWA’s service area. Accordingly, the CVWD and DWA groundwater extraction monitoring programs provide relatively accurate extraction information for the Indio Subbasin.
Table 4-1 summarizes the groundwater extraction volumes in the Indio Subbasin in WY 2020‐2021 by water use sector. The methods of measurement and corresponding measurement accuracy are also provided. The table shows that in WY 2020‐2021, a total of 285,351 AF of groundwater was extracted from the Indio Subbasin. Of the total volume extracted, groundwater production of 281,551 AF was extracted from 574 metered wells in the Indio Subbasin. The remaining 3,800 AF of groundwater extraction is estimated for uses that are not required to report extraction amounts to any of the agencies:
1) industrial tribal water use (1,100 AF), 2) recreational tribal water use (1,200 AF), and 3) minimal pumpers (entities extracting less than 25 AFY in CVWD’s service area and less than 10 AFY in DWA’s service area) combined with unclassified tribal water use (1,500 AF).
Table 4-1 WY 2020-2021 Groundwater Extractions by Water Use Sector in the Indio Subbasin Water Use
Sector
Groundwater
Extractions
(AF)
Method of
Measurement
Accuracy of
Measurement
Agriculture1 46,561 100% metered ±2%
Industrial2 1,288 15% metered ±2%
85% estimated ±50%
Urban3 236,002 99% metered ±2%
1% estimated ±50%
Undetermined4 1,500 100% estimated ±50%
Total Production 285,351
Notes: ` AF ‐ acre‐feet AFY ‐ acre‐feet per year 1 – Includes crop irrigation and fish farms.
2 – Includes 1,100 AF of estimated unreported extractions for industrial tribal water use.
3 – Total includes municipal, golf courses and other uses. Total also includes 1,200 AF of estimated unreported extractions for recreational tribal water use. Of the total urban use, 2,187.3 AF is exported for use outside the Indio Subbasin. 4 – Estimated unreported extraction by minimal pumpers (including small water systems, domestic wells, and other private wells) who do not have to report production to CVWD (<25 AFY) or DWA (<10 AFY) and estimated additional unclassified tribal water use.
Indio Subbasin Annual Report
for Water Year 2020-2021 4-2 TODD / W&C
The total groundwater extracted in WY 2020‐2021 represents an increase of 18,597 AF (7 percent) compared to the volume extracted in WY 2019‐2020 (266,754 AF). The agricultural water use sector (including fish farms) experienced a volumetric increase in water use (1,500 AF) compared to WY 2019‐ 2020, or 3.3 percent. The industrial sector experienced a small volumetric decrease in water use of 94 AF compared to WY 2019‐2020, or 6.8 percent. Urban usage experienced a volumetric increase in water use of 17,191 AF compared to WY 2019‐2020, or 7.9 percent. The water use by golf courses and other users was included in the urban sector.
Note that Table 4-1 includes a portion of groundwater extracted from the Indio Subbasin that is exported for use outside the Indio Subbasin. Groundwater volumes exported for use outside the Indio Subbasin in WY 2020‐2021 are described in further detail in Section 6.
Figure 4-1 shows the location of groundwater extraction in the Indio Subbasin based on public land survey sections. The volume of groundwater extraction is indicated by color with dark blue sections corresponding to groundwater extraction greater than 5,000 AF per square mile. Such areas are generally located near urban centers, including the cities of Palm Springs, Cathedral City, Rancho Mirage, Palm Desert, and Indio.
Indio Subbasin Annual Report
for Water Year 2020-2021 4-3 TODD / W&C
Figure 4-1 WY 2020-2021 Groundwater Production
Indio Subbasin Annual Report
for Water Year 2020-2021 5-1 TODD / W&C
5. SURFACE WATER
This section presents the surface water supplies and use for the Indio Subbasin for WY 2020‐2021. Surface water supplies consist of local surface water, imported Colorado River water from the Coachella Canal, State Water Project (SWP) and other exchange water from the Colorado River Aqueduct (CRA), and recycled water produced by publicly owned wastewater reclamation plants.
5.1 LOCAL PRECIPITATION
Natural surface water flow in the Coachella Valley occurs as a result of precipitation, precipitation runoff, and stream flow originating from the San Bernardino and San Jacinto Mountains, with lesser amounts originating from the Santa Rosa Mountains. Most precipitation occurs from December through February, though intense precipitation events from subtropical thunderstorms can occur during the summer months. The precipitation that occurs within the tributary watersheds either evaporates, is consumed by native vegetation, percolates into underlying alluvium and fractured rock, or becomes runoff, which can be captured by mountain‐front debris basins and percolated into the aquifer. A portion of the flow percolating into the mountain watersheds eventually becomes subsurface inflow to the Subbasins.
Precipitation data for WY 2020‐2021 collected for 12 precipitation monitoring stations are provided in Table 5-1. Station locations are shown on Figure 5-1. The annual precipitation for these stations during WY 2020‐2021 averaged 2.81 inches, or approximately 58 percent relative to the long‐term average.
5.2 LOCAL STREAMFLOW
Streamflow is measured by the USGS at 19 stations in the Indio Subbasin. Table 5-2 shows the station names and numbers, and the recorded streamflow volumes for WY 2020‐2021. Stream gauge locations are shown on Figure 5-1.
Note that some streams (e.g., Whitewater River, Snow Creek, and Falls Creek) are gauged at multiple locations. For example, the Whitewater River is gauged at six locations. USGS gauges 10257548 and 10257549 are downstream from where imported water is released at the WWR‐GRF. USGS gauge 10259540 measures the flow in the CVSC before it enters the Salton Sea. Snow Creek and Falls Creek are each gauged at two locations (upgradient and downgradient of respective diversion structures).
Differences for each creek are calculated based on the difference between the upstream and downstream gauges and reported as a separate station by the USGS.
5.2.1 Direct Use of Local Surface Water
DWA operates stream diversions facilities on Snow, Falls, and Chino Creeks, and captures subsurface flow from the Whitewater River Canyon. During WY 2020‐2021, 719 AF of local surface water was directly used as shown in Table 5-3, all of which was used for urban and agricultural water supply in DWA’s service area.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-2 TODD / W&C
Table 5-1 WY 2020-2021 Coachella Valley Precipitation Data (Inches) Station Name1 Whitewater
North Snow Creek Desert Hot
Springs Tachevah Dam Tram Valley Cathedral City Thousand Palms
Palm Springs
Sunrise Edom Hill Oasis Mecca Landfill
III
Thermal
Airport
Subbasin Indio Indio Mission Creek Indio Indio Indio Indio Indio Mission Creek Indio Indio Indio Station Number 233 207 57 216 224 34 222 442 436 431 432 443 Latitude 33°59'23.06" 33°53'32.64" 33°58'2.85" 33°49'51.26" 33°50'11.56" 33°46'51.49" 33°49'1.66" 33°48'35.94" 33°53'7.52" 33°26'21.64" 33°34'20.19" 33°37'53.90" Longitude 116°39'21.39" 116°41'41.06" 116°29'39.93" 116°33'31.53" 116°36'49.72" 116°27'29.69" 116°23'46.30" 116°31'37.94" 116°26'18.48" 116° 4'44.83" 116° 0'15.33" 116° 9'50.81" Elevation
(ft-msl) 2,220 1,658 1,223 570 2,675 283 230 397 1,038 ‐108 13 ‐122
October 0 0 0 0.01 0 0 0 0 0 0 0.01 0
November 0.92 0.65 0.02 0.02 0.22 0.02 0 0.06 0 0 0.01 0 December 1.17 1.52 0.2 0.28 0.54 0.19 0.11 0.26 0.12 0 0 0.05 January 2.14 1.82 0.5 0.82 1.63 0.45 0.31 0.7 0.43 0.35 0.35 0.28 February 0.46 0.09 0.09 0 0.03 0 0 0 0.05 0 0.02 0
March 1.68 1.88 0.15 0.01 0.51 0.09 0 0.09 0.04 0.02 0.02 0.01 April 0 0 0 0 0.01 0 0 0 0 0 0.01 0
May 0 0 0 0 0 0 0 0 0 0 0 0
June 0.03 0 0 0 0.04 0.01 0 0.01 0 0 0 0
July 1.04 0.79 0.66 0.79 1 0.87 0.47 0.87 1.27 0.2 0.13 0.45 August 0 0 0 0 0 0 0 0 0.07 0.06 0.26 0.17
September 0 0.79 0.48 0.52 0.34 0.01 0.04 0.18 0.05 0.41 0.23 0.01 Total 7.44 7.54 2.1 2.45 4.32 1.64 0.93 2.17 2.03 1.04 1.04 0.97 Average 2.81
Notes:
Precipitation in
inches
1 – Two precipitation monitoring stations located in the Mission Creek Subbasin (Desert Hot Springs and Edom Hill) are included here primarily to fully characterize water year precipitation in the Coachella Valley region. However, data from these stations are not used in any Indio Subbasin‐specific calculations.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-3 TODD / W&C
Figure 5-1 Climate and Streamflow Monitoring Station
Indio Subbasin Annual Report
for Water Year 2020-2021 5-4 TODD / W&C
Table 5-2 WY 2020-2021 Local Streamflow Measurements for the Indio Subbasin Station
Number Station Name
WY
2020-
2021
Flows
(AF)
10256500 Snow Creek Near White Water Ca 1,392
10256501 Snow Creek and Diversion Combined Ca 1,792
10256550 Snow Creek Diversion Near White Water Ca1 487 10257499 Falls Creek Diversion Near Whitewater Ca2 0
10257500 Falls Creek Near Whitewater Ca 317
10257501 Falls Creek and Diversion Combined Ca1 273
10257548 Whitewater River At Windy Point Main Channel Ca 86,781 10257549 Whitewater River At Windy Point Overflow Channel Ca 43 10257550 Whitewater River At Windy Point Near Whitewater Ca 86,824 10257720 Chino Canyon Creek Below Tramway Near Palm Springs Ca 3 10258000 Tahquitz Creek Near Palm Springs Ca 364
10258500 Palm Canyon Creek Near Palm Springs Ca 18
10258700 Murray Canyon Creek Near Palm Springs Ca 60
10259000 Andreas Creek Near Palm Springs Ca 1,062
10259050 Palm Canyon Wash Near Cathedral City Ca 1
10259100 Whitewater River At Rancho Mirage Ca 2
10259200 Deep Creek Near Palm Desert Ca 1
10259300 Whitewater River At Indio Ca 11
10259540 Whitewater River Near Mecca Ca 47,748
Notes:
Ca ‐
California
AF ‐ acre‐
feet
Indio Subbasin Annual Report
for Water Year 2020-2021 5-5 TODD / W&C
Indio Subbasin Annual Report
for Water Year 2020-2021 5-6 TODD / W&C
Table 5-3 WY 2020-2021 Direct Use of Local Surface Water in the Indio Subbasin Water Use Sector Surface Water Use
(AF)
Method of
Measurement
Accuracy of
Measurement
Agriculture1 353 100% metered ±2%
Industrial 0 Not applicable Not applicable
Urban1 366 100% metered ±2%
Total Surface Water Use 719
Notes:
AF ‐ acre‐feet
1 ‐ Applied proportion based on the 5‐year average agricultural and urban use of DWA surface water.
5.3 IMPORTED WATER DELIVERIES
The Indio Subbasin has water allocations from two imported surface water sources: the Colorado River and the SWP. Colorado River water is delivered to the eastern portion of the Indio Subbasin via the Coachella Canal and to the western portion through the Colorado River Aqueduct (CRA). There is currently no infrastructure to physically deliver SWP water to the Coachella Valley. To exercise SWP deliveries, CVWD and DWA exchange the deliveries with MWD for Colorado River water, which is delivered to the western portion of the Subbasin via the CRA. Imported surface water is used to replenish groundwater and as an alternative source to groundwater pumping in the Indio Subbasin. CVWD and DWA augment natural recharge of the Indio Subbasin through their respective groundwater replenishment programs.
There are two types of groundwater replenishment programs in the Indio Subbasin: 1) direct replenishment, in which imported surface water is percolated directly into the aquifer, and 2) in‐lieu replenishment, in which imported surface water or recycled water is provided directly to irrigation customers, thus reducing or eliminating the use of pumped groundwater.
5.3.1 Colorado River Water
Colorado River water has been a significant water supply source for the Indio Subbasin area since the Coachella Canal was completed in 1949. CVWD is the only agency in the Indio Subbasin that receives Colorado River water deliveries.
California’s Colorado River water rights are defined by the 1922 Colorado River Compact and the 1928 Boulder Canyon Project Act. CVWD’s portion of California’s rights were set by the 1931 Seven Party Agreement (USBR, 1931).3 Under the Seven Party Agreement, CVWD receives 330,000 AF of Priority 3A Colorado River water and has water rights as part of the first 3.85 million AFY of Colorado River water allocated to California. The Coachella Canal originates at Drop 1 on the All‐American Canal and extends approximately 123 miles, terminating in CVWD’s Lake Cahuilla. This water is then delivered to the CVWD’s Improvement District No. 1 (ID‐1) service area, which encompasses 136,400 acres covering most of the East Valley and a portion of the West Valley north of Interstate 10.
3 The seven parties include CVWD, MWD, Imperial Irrigation District, Palo Verde Irrigation District, City of Los Angeles, City of San Diego, and County of San Diego.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-7 TODD / W&C
In 2003, CVWD, MWD, and Imperial Irrigation District (IID) successfully negotiated the Quantification Settlement Agreement (QSA), which quantifies the Colorado River water allocations through 2077 and supports the transfer of water between agencies. The QSA defines CVWD’s Colorado River water supply entitlement on a calendar year basis. Under the QSA, CVWD has a base allotment of 330,000 AFY. CVWD negotiated water transfer agreements with MWD and IID that increased CVWD supplies by an additional 123,000 AFY. From CVWD’s QSA entitlement, 26,000 AFY is transferred to San Diego County Water Authority (SDCWA) as part of the Coachella Canal Lining Project and 3,000 AFY is transferred to Indian Present Perfected Rights. As a result, CVWD’s net QSA supply will increase to 424,000 AFY by 2026 and remain at that level until 2047, decreasing to 421,000 AFY until 2077, when the agreement terminates (Secretary of the Interior, 2003). CVWD’s Colorado River entitlement under the QSA for Calendar Year (CY) 2021 is summarized in Table 5-4. CVWD’s total Colorado River water entitlements for CY 2021 under the QSA is 399,000 AFY, an increase of 5,000 AF as compared to CY 2020 reflecting the change in Second IID/CVWD Transfer water from 23,000 AF in calendar year CY 2020 to 28,000 AF in CY 2021.
Additionally, under the 2003 QSA, MWD transferred 35,000 AFY of its SWP Table A Amount to CVWD. This SWP water is exchanged for Colorado River water and can be delivered at Imperial Dam for delivery via the Coachella Canal to the eastern portion of the Indio Subbasin or at Lake Havasu for delivery via the Colorado River Aqueduct to the western portion of the Indio Subbasin at the WWR‐GRF. The 2019 Second Amendment (CVWD, 2019b) guaranteed delivery of the 35,000 AFY from 2019 to 2026, for a total of 280,000 AFY of water to the WWR‐GRF during that timeframe. MWD can deliver the water through CVWD’s Whitewater Service Connections (for recharge at WWR‐GRF) or via the Advance Delivery account.
The MWD/IID Transfer originated in a 1989 agreement with MWD to receive 20,000 AF of its Colorado River supply. The 2019 Amended and Restated Agreement for Exchange and Advance Delivery of Water (CVWD, 2019a) defined the exchange and delivery terms between MWD, CVWD, and DWA. The 2019 Second Amendment to Delivery and Exchange Agreement (CVWD, 2019b) reduced CVWD’s annual delivery of the MWD/IID Transfer to 15,000 AFY, for a total of 105,000 AF, if taken at the Whitewater Service Connections (for recharge at WWR‐GRF) between 2020 and 2026. For those seven years, MWD keeps the remaining 5,000 AFY.
Colorado River water is delivered extensively throughout the East Valley to agricultural users, golf courses, and homeowner’s associations for irrigation, in addition to being used in CVWD’s groundwater replenishment programs at WWR‐GRF, TEL‐GRF, and PD‐GRF. Colorado River Water is also delivered to the Mid‐Valley area via the Mid‐Valley Pipeline (MVP) where it is delivered directly or blended with CVWD’s recycled water for golf course and open space irrigation.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-8 TODD / W&C
Table 5-4 CY 2021 CVWD Colorado River Water Entitlements under the QSA Budget Component Amount
(AF)
Base Entitlement 330,000
Less Coachella Canal Lining (to SDCWA) ‐26,000
Less Miscellaneous/Indian PPRs1 ‐3,000
1988 MWD/IID Approval Agreement 20,000
First IID/CVWD Transfer 50,000
Second IID/CVWD Transfer 28,000
MWD/CVWD Replacement Water2 0
Total Colorado River Entitlements 399,000
MWD SWP Transfer 35,000
Total Available Deliveries 434,000
Notes:
AF ‐ acre‐feet
SDCWA ‐ San Diego County Water Authority
PPRs ‐ Present Perfected Rights
IID ‐ Imperial Irrigation District
CVWD ‐ Coachella Water District
MWD ‐ Metropolitan Water District of Southern California 1 ‐ Indian Present Perfected Rights
2 ‐ MWD assumes the obligation to provide 50,000 acre‐feet per year (AFY) of replacement water after 2048.
5.3.2 State Water Project (Exchange Water)
DWR manages the SWP and determines the amount of SWP water available for delivery based on hydrologic, storage, water rights, water quality, and environmental factors, including requirements for the Sacramento‐San Joaquin Delta (Delta). The available water is then allocated to the SWP contractors according to Table A amounts (CVWD, 2012a). During CY 2021, DWR allocated 5 percent of the Table A amounts to contractors. This is less than the 58 percent long‐term average SWP deliveries across all water years through 2015 due to below average precipitation during winter of WY 2020‐2021. DWR allocated 20 percent of CVWD’s and DWA’s Table A amounts in CY 2020.
While CVWD and DWA have contracts for Table A water (Table 5-5), there are no physical facilities to deliver SWP water to the Coachella Valley. CVWD’s and DWA’s SWP water is exchanged with MWD for an equal amount of Colorado River water from MWD’s CRA. Since 1973, this exchange water has been delivered to the Indio Subbasin at the WWR‐GRF or the MC‐GRF turnout. As summarized in Table 5-5, CVWD and DWA SWP allocations include their original Table A allocations and the following transfer agreements:
• MWD Transfer (2003): CVWD and DWA executed a Delivery and Exchange Agreement with MWD for a combined total of 100,000 AFY as a permanent transfer to be delivered to the WWR‐GRF or the MC‐GRF.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-9 TODD / W&C
• Tulare Lake Basin Transfer #1 (2004): CVWD purchased an additional 9,900 AFY of Table A water from Tulare Lake Basin Water Storage District in Kings County. • Tulare Lake Basin Transfer #2 (2007): CVWD and DWA executed transfer agreements with Tulare Lake Basin Water Storage District for 5,250 AFY and 1,750 AFY, respectively, totaling 7,000 AFY. • Berrenda Transfer (2007): CVWD and DWA executed transfer agreements with Berrenda Mesa Water District in Kern County for 12,000 AFY and 4,000 AFY, respectively, totaling 16,000 AFY.
Table 5-5 State Water Project Table A Amounts
Agency
Original
SWP Table A
(AFY)
MWD
Transfer
(AFY)
Tulare Lake
Basin
Transfer #1
(AFY)
Tulare Lake
Basin
Transfer #2
(AFY)
Berrenda
Transfer
(AFY)
Total
(AFY)
CVWD 23,100 88,100 9,900 5,250 12,000 138,350
DWA 38,100 11,900 ‐ 1,750 4,000 55,750
Total 61,200 100,000 9,900 7,000 16,000 194,100
Notes:
SWP ‐ State Water Project
MWD ‐ Metropolitan Water District of Southern California AFY ‐ acre‐feet per year
CVWD ‐ Coachella Valley Water District
DWA ‐ Desert Water Agency
Along with the transfer agreements described above, CVWD also acquired an additional 35,000 AFY of SWP transfer water from the QSA. The SWP QSA water is exchanged for Colorado River water and can be delivered at Imperial Dam for delivery via the Coachella Canal to the eastern portion of the Indio Subbasin or at Lake Havasu for delivery via the CRA to the western portion of the Indio Subbasin at the WWR‐GRF.
The 1984 Advance Delivery Agreement between CVWD, DWA, and MWD, signed in 1985 and amended in 2019 by the Amended and Restated Agreement for Exchange and Advance Delivery of Water (CVWD, 2019a), allows MWD to deliver up to 800,000 AFY of Colorado River water to be credited against its future SWP exchange obligations. Advance deliveries of exchange water are highly variable and concentrated in wet years, with the Indio Subbasin providing storage of the pre‐delivered supplies. Along with transfers listed in Table 5-5, CVWD and DWA have explored additional water transfers, for example water purchases from programs such as SWP Article 21 and Turnback Water Pool, Governor’s Drought Water Bank, Yuba Accord, and Rosedale‐Rio Bravo Water Storage District. Table 5-6 summarizes the WY 2020‐ 2021 deliveries to MWD of SWP water, which MWD then exchanges for Colorado River water and delivers to CVWD and DWA at their respective facilities. Advance deliveries received by CVWD and DWA are credited to the Advance Delivery Account.
As part of the SWP Exchange Agreement, MWD received a total of 65,151 AF of SWP water allocated to CVWD and DWA in WY 2020‐2021. Of this amount, 25,940 AF was Table A water, 2,174 AF was Dry Year (Yuba) water, and 11,875 AF was Rosedale‐Rio Bravo transfer water. MWD also received 25,162 AF of SWP water transferred to CVWD under the QSA. As part of CVWD’s annual delivery of the MWD/IID Transfer, 15,000 AF were also delivered at the WWR‐GRF.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-10 TODD / W&C
As shown in Table 5-6, CVWD and DWA received 106,181 AF of SWP Exchange water at the WWR‐GRF and 427 AF at the MC‐GRF (in the Mission Creek Subbasin), for a total delivery to the Coachella Valley of 106,608 AF. This was 57,727 AF more than the 48,881 AF delivered in WY 2019‐2020, with an additional 36,925 AF added to the Advance Delivery Account. At the end of WY 2020‐2021, 304,381 AF was stored in MWD’s Advance Delivery Account in the Indio Subbasin. - In WY 2020‐2021, water delivered to WWR‐GRF totaled 106,181 AF. SWP water is used entirely for groundwater replenishment at WWR‐GRF. No SWP exchange water is directly delivered to local customers.
5.3.3 Total Imported Deliveries
Table 5-7 summarizes the total imported water in the Indio Plan Area by water use sector and source during WY 2020‐2021. Table 5-7 is split by the total imported deliveries for direct use by local customers in the Plan Area (69,683 AF) and the total imported deliveries for groundwater replenishment (106,608 AF). Total water imported to the Indio Plan Area was 442,411 AF. This includes 2,689 AF of imported water deliveries used outside the Indio Subbasin.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-11 TODD / W&C
Table 5-6 Deliveries of CVWD and DWA SWP Water to MWD in WY 2020-2021 Description CVWD
(AF)
DWA
(AF)
Total
(AF)
Table A 18,491 7,449 25,940
Article 21 “Interruptible” 0 0 0
Turnback Pool A and B 0 0 0
Multi‐Year Pool 0 0 0
Dry Year (Yuba) 1,440 734 2,174
Flex Storage Payback 0 0 0
Article 56 (c) “Carryover” from 2019 delivered in 2020 0 0 0 Rosedale‐Rio Bravo 11,875 0 11,875
CVWD QSA Transfer1 25,162 0 25,162
Total Delivered to MWD 56,968 8,183 65,151
1988 MWD/IID Approval Agreement Exchange2 4,532
Total Exchanged 69,683
Water Delivered to CVWD and DWA at Whitewater
River‐GRF (WWR‐GRF) ‐‐ ‐‐ 106,181
Water Delivered to CVWD and DWA at Mission Creek
GRF (MC‐GRF) ‐‐ ‐‐ 427
Total Delivered to Coachella Valley 106,608
Credit to/from Advanced Delivery Account3 ‐‐ ‐‐ 36,925
Advanced Delivery Account Balance as of September 30,
2021 ‐‐ ‐‐ 304,381
Notes: AF ‐ acre‐feet CVWD ‐ Coachella Valley Water District DWA ‐ Desert Water Agency MWD ‐ Metropolitan Water District of Southern California IID ‐ Imperial Irrigation District QSA ‐ Quantification Settlement Agreement WWR‐GRF ‐ Whitewater River Groundwater Replenishment Facility MC‐GRF ‐ Mission Creek Groundwater Replenishment Facility 1 – The 35,000 AFY of SWP water available through the QSA may be delivered at either Imperial Dam or Whitewater River and is not subject to SWP or Colorado River reliability. 2 ‐ Accounts for ‐5,000 AFY reduction in MWD/IID Approval Agreement deliveries from 2020–2026 per the 2019 Amendments with MWD.
3 – Credit to/from Advanced Delivery Account is the difference between Total Water Delivered to MWD and Total Water Delivered to the Indio and Mission Creek Subbasins to CVWD and DWA.
Indio Subbasin Annual Report
for Water Year 2020-2021 5-12 TODD / W&C
Table 5-7 WY 2020-2021 Imported Water for Direct Use and Replenishment in Plan Area Water Use Sector Water Source
Imported
Water
Use
(AF)
Method of
Measurement
Accuracy of
Measurement
Agriculture1 Coachella Canal 245,853 100%
metered ±2%
Urban2 Coachella Canal 41,710 100%
metered ±2%
Industrial Coachella Canal 0 100%
metered ±2%
Environmental3 Coachella Canal 0 Not
applicable ‐‐
Total Imported Water for Direct Use in the Plan Area4 287,563 Exported for Use Outside of Indio Subbasin5 2,689
Total Imported Water for Direct Use in Indio Subbasin 284,874 Groundwater Replenishment Coachella Canal6 48,667 100%
metered ±2%
Groundwater Replenishment SWP Exchange/CRA 106,181 100% metered ±2%
Total Imported Water for Groundwater
Replenishment 154,848
Total Imported Water in the Plan Area 442,411
Notes: AF ‐ acre‐feet SWP ‐ State Water Project 1 ‐ Includes crop irrigation and fish farms. Includes 1,117 AF for agricultural use outside the Indio Subbasin. 2 ‐ Includes municipal and recreational uses. Includes 1,572 AF for urban use outside Indio Subbasin. 3 ‐ A small amount of Coachella Canal water is used for wildlife habitat enhancement and mitigation in the East Salton Sea Groundwater Basin.
4 ‐ Excludes regulatory water (6,984 AF) and other conveyance losses. 5 ‐ Water delivered to agricultural and urban users outside Indio Subbasin. 6 ‐ Includes 37,878 AF to Thomas E. Levy Groundwater Replenishment Facility (TEL‐GRF) and 10,789 AF to Palm Desert Groundwater Replenishment Facility (PD‐GRF).
5.4 RECYCLED WATER
Figure 5-2 shows the locations of water reclamation plants (WRPs) and other wastewater treatment and discharge facilities in the Indio Subbasin. Currently, three WRPs provide recycled water for irrigation in the Indio Subbasin. Of these, two recycled water facilities are operated by CVWD (WRP‐7 and WRP‐10) and one recycled water facility is operated by DWA using secondary effluent from the City of Palm Springs WWTP.
CVWD WRP‐7, located north of Indio, has a tertiary treatment capacity of 2.5 million gallons per day (mgd).
Recycled water from WRP‐7 is used for irrigation of golf courses at Sun City in north Palm Desert and
Indio Subbasin Annual Report
for Water Year 2020-2021 5-13 TODD / W&C
Shadow Hills in north Indio. Recycled water not used for irrigation is percolated at onsite and offsite percolation ponds. WRP‐7 delivered 2,594 AF of recycled water in WY 2020‐2021.
CVWD WRP‐10, located in Palm Desert, has a tertiary treatment capacity of 15 mgd and delivers recycled water for irrigation of golf courses and homeowner’s associations landscaping within the mid‐valley area.
WRP‐10 recycled water is blended with Canal water particularly in summer months when recycled water supply alone cannot meet non‐potable irrigation demands. WRP‐10 delivered 7,529 AF of recycled water in WY 2020‐2021.
The DWA WRP is located in the City of Palm Springs and has a tertiary treatment capacity of 10 mgd. DWA provides tertiary treatment of secondary treated supply from the City of Palm Springs’s WWTP for irrigation of parks and other greenscapes in the Palm Springs area. DWA WRP supplied 3,877 AF of recycled water in WY 2020‐2021, including 444 AF for onsite use. Table 5-8 shows that a total of 14,000 AF of recycled water was used in WY 2020‐2021 to offset groundwater pumping.
Four additional WRPs in the Indio Subbasin treat wastewater, but do not generate recycled water. These wastewater treatment facilities are operated by the Valley Sanitary District (VSD), the City of Coachella, and CVWD (WRP‐2 and ‐4); locations of each facility are shown on Figure 5-2. For these wastewater treatment facilities, treated effluent is discharged either to on‐site percolation/evaporation ponds or to the CVSC. Additionally, the Kent SeaTech Fish Farm has a National Pollution Discharge Elimination System (NPDES) permit to discharge water to the CVSC. Table 5-9 summarizes the volumes of wastewater treated, recycled, and disposed in the Indio Subbasin by facility (listed from northwest to southeast).
Indio Subbasin Annual Report
for Water Year 2020-2021 5-14 TODD / W&C
Figure 5-2 Water and Wastewater Facilities
Indio Subbasin Annual Report
for Water Year 2020-2021 5-15 TODD / W&C
Table 5-8 WY 2020-2021 Recycled Water Use in the Indio Subbasin Water Use Sector Water Source
Recycled
Water Use
(AF)
Method of
Measurement
Accuracy of
Measurement
Urban1 DWA WRP 3,877 100% metered ±2%
Urban1 CVWD WRP 7 2,594 100% metered ±2%
Urban1
CVWD WRP
10 7,529 100% metered ±2%
Total Recycled
Water Use 14,000
Notes: AF ‐ acre‐feet 1 ‐ Includes municipal, recreational, and reclamation plant (including onsite) water uses.
Table 5-9 WY 2020-2021 Wastewater Treatment, Reuse, and Disposal in the Indio Subbasin Facility
Wastewater
Treated
(AF)
Recycled
Water Use1
(AF)
Recycled
Onsite WRP
Use2
(AF)
Disposal
Percolation/
Evaporation
(AF)
Disposal
to CVSC
(AF) CPS WWTP/DWA WRP 6,260 3,433 444 2,383 N/A
CVWD WRP 7 3,246 2,202 392 652 N/A
CVWD WRP 10 8,926 7,148 382 1,396 N/A
Valley SD WRP 6,911 0 0 0 6,911
City of Coachella WRP3 3,017 0 0 0 3,017
CVWD WRP 4 5,835 0 0 0 5,835
Kent SeaTech 6,086 0 0 0 6,086
CVWD WRP 24 15 0 0 15 0
Total 40,296 12,783 1,218 4,446 21,849
Notes:
AF ‐ acre‐feet
WRP ‐ Water Reclamation Plant
CVSC ‐ Coachella Valley Stormwater Channel
CPS WWTP ‐ City of Palm Springs Wastewater Treatment Plant DWA WRP ‐ Desert Water Agency Water Reclamation Plant
CVWD WRP ‐ Coachella Valley Water District Water Reclamation Plant 1 ‐ Recycled water sold to customers.
2 ‐ Recycled water for WRP onsite uses.
3 ‐ Data downloaded from the SWRCB.
4 ‐ Includes 12 AF of percolation and 3 AF of evaporation.
Indio Subbasin Annual Report
for Water Year 2020-2021 6-1 TODD / W&C
6. TOTAL WATER USE
This section presents the total water use for the Plan Area for WY 2020‐2021. Table 6-1 presents a summary of water use by water use sector and water source. As shown in Table 6-1, a total of 587,632 AF of water was used within the Plan Area, and of that, 4,876 AFY was exported for use outside of the Indio Subbasin. Figure 6-1 shows a comparison of supply and demand for direct use within the Plan Area for WY 2020‐2021.
The total water use in the Plan Area was 587,632 AFY. This represents an increase of 31,965 AF or 6 percent compared to WY 2019‐2020 (555,667 AF). Export uses include (a) Colorado River water exported outside the Indio Subbasin for agricultural use (1,117 AF) and urban use (1,572 AF) and (b) groundwater pumped from the Indio Subbasin and delivered to CVWD customers in Imperial and Riverside counties on the east and west sides of the Salton Sea (East and West Salton Sea Basins) (2,135 AFY) and pumped by MSWD and delivered to its customers in the Mission Creek (52 AFY).
As summarized on Figure 6-1, total Plan Area water use is calculated by summing groundwater production, local surface water diversions, Coachella Canal water, and recycled water for agricultural, industrial, urban, and other undetermined uses, and including water exports for use outside the Indio Subbasin.
The 2022 Alternative Plan Update forecasted demand in the Indio Subbasin from 2020 to 2045 based on average current uses, because water demand varies from year to year due in part to hydrologic conditions (wet and dry year types). The 2022 Alternative Plan Update estimated total water use in 2020 to average 594,823 AF. Figure 6-2 compares the forecasted demand volume to the actual water use in WYs 2016‐ 2017 through 2020‐2021 and the five‐year average (573,435 AFY, shown as a dashed line on Figure 6-2).
Compared to the projected demand for 2021, the five‐year average is lower than projected demands by approximately 20,000 AF.
DWR requires that SGMA Annual Reports be accompanied by tables summarizing water use by type and source. The following required tables are included as Appendix B.
A – Groundwater Extractions
B – Groundwater Extraction Methods
C – Surface Water Supply
D – Total Water Use
Indio Subbasin Annual Report
for Water Year 2020-2021 6-2 TODD / W&C
Table 6-1 WY 2020-2021 Total Water Use by Sector and Source in the Plan Area and Indio Subbasin Water Use Sector
Water Source (AF)
Method of
Measurement
Accuracy of
Measurement Groundwater
Production
Local
Surface
Water
Imported
Water:
Colorado
River4
Imported
Water:
SWP Exchange
Recycled
Water
Total Direct
Water Use
Agriculture1 46,561 353 245,853 ‐ ‐ 292,767 99% metered 1% estimated
±2%
±50%
Industrial 1,288 ‐ ‐ ‐ ‐ 1,288
16% metered
84%
estimated
±2%
±50%
Urban2 236,002 366 41,710 ‐ 14,000 292,077 99% metered
1% estimated
±2%
±50%
Undetermined3 1,500 ‐ ‐ ‐ ‐ 1,500 100%
estimated ±50%
Total Water Use in the Plan
Area 285,351 719 287,563 0 14,000 587,632
Water Exported for Use
Outside Indio Subbasin 2,187 0 2,689 0 0 4,876
Total Direct Water Use in
Indio Subbasin 283,164 719 284,874 0 14,000 582,755
Notes: AF ‐ acre‐feet SWP ‐ State Water Project 1 – Includes crop irrigation and fish farms; includes 1,336 AF of imported Colorado River water exported for agricultural use in the Desert Hot Springs Subbasin outside the Indio Subbasin. Excludes 1,117 AF for agricultural use outside the Indio Subbasin. 2 – Includes municipal and recreational uses; includes 1,353 AF of Canal water and 2,187 AF of groundwater exported for use outside the Indio Subbasin for urban use in the Mission Creek Subbasin, Desert Hot Springs Subbasin, and West Salton Sea and East Salton Sea subbasins. And includes 1,572 AF of Canal water for golf use outside Indio Subbasin.
3 – Estimated production by minimal pumpers who do not report production to CVWD (<25 AFY) or DWA (<10 AFY) and estimated additional unreported tribal water use. 4 ‐ Excludes regulatory water (8,409 AF) and conveyance losses.
Indio Subbasin Annual Report
for Water Year 2020-2021 6-3 TODD / W&C
Figure 6-1 Comparison of Supply and Demand for Direct Use for the Plan Area WY 2020-2021
*Note: In previous Annual Reports, this chart compares Indio Subbasin only.
Indio Subbasin Annual Report
for Water Year 2020-2021 6-4 TODD / W&C
Figure 6-2 Water Demand Actual and Forecasted
Indio Subbasin Annual Report
for Water Year 2020-2021 7-1 TODD / W&C
7. CHANGE IN GROUNDWATER STORAGE
This section presents the groundwater balance and change in storage for the Indio Subbasin for WY 2020‐ 2021.
7.1 GROUNDWATER BALANCE
The water budget compares the inflows to and outflows from the Indio Subbasin. The difference between inflows and outflows defines the change in storage over a specific time period, in this case, WY 2020‐2021.
The annual water balance for the Indio Subbasin in WY 2020‐2021 shows an increase in groundwater storage of 5,954 AF. A discussion of major inflows and outflows from the Indio Subbasin is presented below and a stacked bar chart of total groundwater inflows and outflows is presented on Figure 7-1. Some elements of the methodology used in calculating the water balance change in storage were modified in WY 2020‐2021, including use of the numerical model to be more consistent with the 2022 Alternative Plan Update, as explained below. The numerical model was updated from December 2019 through September 2021.
7.1.1 Groundwater Inflows
Major inflows to the Indio Subbasin include natural recharge, subsurface inflow (from adjacent subbasins and potentially from the Salton Sea), return flows from use and wastewater percolation, and groundwater replenishment (or artificial recharge).
Natural Recharge
Precipitation that falls in the San Jacinto, Santa Rosa, and Little San Bernardino mountains is the primary source of natural recharge in the Indio Subbasin. A portion of the surface runoff produced by precipitation percolates directly into the subsurface or infiltrates through streambeds. The annual volume of natural recharge varies significantly as the annual volume of precipitation varies widely.
Natural recharge was estimated using the same methodology that was developed for the 2022 Alternative Plan Update numerical model. As part of the 2022 Alternative Plan Update, the groundwater flow model and data were updated to reflect hydrologic conditions through WY 2020‐2021. Recharge from mountain front inflow and from percolation of stream flows into the Indio Subbasin was estimated for 24 watersheds and stream channels along the southwest edge of the model, where the Indio Subbasin interfaces with the consolidated rocks of the San Jacinto and Santa Rosa Mountains.
In past annual reports, the long‐term average value (45,953 AF) was used in the water budget to represent natural recharge. However, more recent years have experienced less than the long‐term average natural recharge and an annual volume is more indicative of natural water year variations. Natural infiltration for WY 2020‐2021 was calculated as 23,897 AF, 52 percent of the long‐term average (1930‐2021).
Indio Subbasin Annual Report
for Water Year 2020-2021 7-2 TODD / W&C
Figure 7-1 Groundwater Balance for the Indio Subbasin WY 2020-2021
Indio Subbasin Annual Report
for Water Year 2020-2021 7-3 TODD / W&C
Subsurface Inflow
Natural inflow to the Indio Subbasin includes subsurface inflows from the San Gorgonio Pass Subbasin, Mission Creek Subbasin, and Desert Hot Springs Subbasin (Table 7-1). Subsurface flow between the Indio Subbasin and adjacent basins in the southeast area of the model (Orocopia Valley, Chocolate Valley and West Salton Sea Basins) is assumed to be negligible due to faulting, semi‐permeable bedrock units comprising adjacent basins, short contact boundaries and relatively flat hydraulic gradients compared with other subbasin/basin contact areas. It is assumed that there is no subsurface flow between the Indio Subbasin and the Orocopia and Chocolate Valleys or the West Salton Sea Groundwater Basin. Inflow amounts from upstream basins were simulated in the 2022 Alternative Plan Update modelling.
Historically, these inflows were estimated to range from 7,000 AFY to 13,000 AFY. The 2022 Alternative Plan Update modeling simulated these long‐term average inflows to be approximately 11,654 AFY, as shown in Table 7-1. Collectively, long‐term average natural recharge (23,897 AF) and subsurface inflows (11,654 AF) applied to WY 2020‐2021 total 35,551 AF.
Table 7-1 WY 2020-2021 Estimated Average Subsurface Inflows into Indio Subbasin Subbasin Boundary Transfer
Estimated
Average
Annual
Underflow
(AF)
San Gorgonio Pass Subbasin to the Indio Subbasin1 8,198 Mission Creek Subbasin to the Indio Subbasin1 3,456
Desert Hot Springs Subbasin (Fargo Canyon) to the Indio Subbasin1 0.2
Total Subsurface Inflow from Neighboring Subbasins 11,654 Notes:
AF ‐ acre‐feet
1 ‐ Based on 2022 Alternative Plan Update numerical model
Infiltration of Applied Irrigation Water
Deep percolation of water applied to agricultural fields, golf courses, and urban landscapes represents a major inflow to the groundwater system and is referred to as irrigation return flow. Irrigation return flows can be calculated based on evapotranspiration (ET), leaching requirements of existing crops and landscaped areas, and assumptions on irrigation methods and their respective efficiencies.
The method of estimating return flows for WY 2020‐2021 is described in the 2022 Alternative Plan Update.
For WY 2020‐2021, irrigation return flow (agricultural, municipal, and golf uses) in the Indio Subbasin was estimated to be 162,320 AF. The geographic distribution of these return flows was developed to update the 2022 Alternative Plan Update model. The municipal return flows include septic system percolation.
Wastewater Percolation
The urban portions of the Indio Subbasin are served primarily by municipal sewer systems that convey wastewater to municipal wastewater treatment/reclamation plants. A portion of the treated wastewater that is not reused is conveyed to percolation/evaporation ponds as described in Section 5. Wastewater
Indio Subbasin Annual Report
for Water Year 2020-2021 7-4 TODD / W&C
disposal to percolation/evaporation ponds was 4,446 AF for WY 2020‐2021. For groundwater balance purposes, a two percent evaporation loss is applied to wastewater evaporation as an outflow.
Groundwater Replenishment
Artificial recharge is accomplished in the western portion of the Indio Subbasin at the WWR‐GRF, in the mid‐valley at the PD‐GRF, and in the eastern portion of the Indio Subbasin at the TEL‐GRF.
The source of replenishment water for the WWR‐GRF is SWP exchange water (exchanged for Colorado River water via the CRA) and QSA water, while the source of replenishment water for the PD‐GRF and TEL‐ GRF is Colorado River water imported through the Coachella Canal. Canal water is delivered to the PD‐ GRF via the MVP.
In WY 2020‐2021, 154,848 AF of imported water was used for groundwater replenishment in the Indio Subbasin. Of this volume, 106,181 AF of SWP exchange water and QSA water was replenished at the WWR‐GRF (see Table 5-7). Of the 48,667 AF of Colorado River (Coachella Canal) water delivered for replenishment, 37,878 AF was replenished at the TEL‐GRF, and 10,789 AF was replenished at the PD‐GRF (Table 5-7). For groundwater balance purposes, a four percent evaporation loss is applied to WWR‐GRF and a two percent evaporation loss is applied to all other replenishment water deliveries as an outflow.
7.1.2 Groundwater Outflows
Indio Subbasin groundwater outflows consist of:
• Groundwater pumping to meet water demands,
• Flow from the semi‐perched aquifer through the agricultural drains into the Salton Sea, • ET from groundwater replenishment, wastewater percolation and semi‐perched aquifer, and • Subsurface flow out of the Indio Subbasin, into the aquifers beneath the Salton Sea.
Groundwater Pumping
Groundwater pumping is the largest component of outflow from the Indio Subbasin. During WY 2020‐ 2021, 285,351 AF of groundwater were pumped for beneficial uses within the Plan Area as shown in Table 4-1.
Flow to Drains
In the eastern portion of the Indio Subbasin, the confining unit of the Upper Aquifer impedes deep percolation of applied water at the surface, resulting in saturated soil conditions that can reduce agricultural productivity. In the 1930s, a network of drains was constructed to alleviate this condition. The CVSC and 27 drains that flow to the Salton Sea receive intercepted shallow groundwater from agricultural fields. Following the delivery of Coachella Canal water to the Coachella Valley in 1949, subsurface (tile) drainage systems were soon installed to control the high‐water table conditions and to intercept poor quality shallow groundwater. CVWD currently maintains 21 miles of open drains and 166 miles of subsurface pipe drains serving 37,425 acres of agricultural lands in the Coachella Valley (CVWD, 2018a).
Provision of shallow drainage reduces the percolation of poor‐quality return flows into the deeper potable aquifers. Flow in the drains increased steadily as additional tile drains were installed, until the early 1970s.
Agricultural drainage flow remained relatively stable through the 1970s and steadily declined through 2009. Drain flow (excluding wastewater discharges and fish farm effluent) has decreased steadily from a
Indio Subbasin Annual Report
for Water Year 2020-2021 7-5 TODD / W&C
high of approximately 158,000 AF in 1976, to 58,800 AF in 1999, and about 40,000 AF in 2009. Since 2009, drain flows have increased in part because of higher groundwater levels in the eastern Indio Subbasin.
CVWD monitors drain flows to the Salton Sea on a monthly basis. The USGS also operates a continuous flow gauge near the terminus of the CVSC (USGS Gauge Number 10256540 on Table 5-1). As shown in Table 7-2, the total measured drain flow to the Salton Sea in WY 2020‐2021 was approximately 80,720 AF.
The CVSC and drain system also receive flows of Coachella Canal water that exceed requested deliveries (regulatory water), treated wastewater, and fish farm effluent. These flows must be deducted from the total flow to calculate the amount of groundwater leaving the Indio Subbasin through the drain system.
Table 7-3 indicates that 52,676 AF of drain water flowed from the shallow groundwater system to the Salton Sea in WY 2020‐2021.
Subsurface Flow to the Salton Sea
Historically, when groundwater levels were relatively high, groundwater naturally flowed toward the Salton Sea. Shallow semi‐perched groundwater discharged into the Salton Sea and deeper groundwater left the Indio Subbasin as subsurface outflow. As groundwater levels in the southeastern portion of the Indio Subbasin declined, the rate of outflow to the Salton Sea decreased.
The Salton Sea is simulated in the 2022 Alternative Plan Update model as a general head boundary (GHB) with time‐varying elevations. The model was updated to reflect actual Salton Sea elevations. Both groundwater outflow to the Sea and inflow from the Sea are simulated, depending on location, time period, and hydraulic gradients between the shallow aquifer and the Sea. Simulated net flow between the Sea and groundwater system is relatively small and has become a net outflow in recent years. In WY 2020‐ 2021, the net subsurface outflow to the Salton Sea was simulated as 2,806 AFY.
Indio Subbasin Annual Report
for Water Year 2020-2021 7-6 TODD / W&C
Table 7-2 WY 2020-2021 Measured Drain Flows from the Indio Subbasin to the Salton Sea Drain
Measured Drain
Flows
(AF)1
A Channel 1,412
Arthur 0.5 1,822
Arthur St. 1,690
Ave 74 488
Ave 76 1,949
Ave 78 360
Ave 79 1,207
Ave 83 489
C Channel 728
Caleb Channel 665
Cleveland 0.5 943
Cleveland East 207
Cleveland West 646
Coachella Valley Storm Water Channel 47,727
D Channel 1,153
E Channel 2,310
F Channel 0
Garfield 0.5 1,771
Garfield St. 1,781
Grant 0.5 1,513
Grant St. 1,081
Hayes 917
Hayes 0.5 347
Johnson St. 3,819
Lincoln‐Oasis 4,114
McKinley 546
McKinley 0.5 492
Oasis‐Grant 544
Total Drain Flows 80,720
Notes:
AF ‐ acre‐feet
1 – Drain flows are measured once per month using current meter and cross‐ sectional areas. If conditions are unsafe for metering, flows are estimated based on the average for the three previous years. Total shown reflects rounding.
Indio Subbasin Annual Report
for Water Year 2020-2021 7-7 TODD / W&C
Table 7-3 WY 2020-2021 Net Subsurface Drain Flow from the Indio Subbasin to the Salton Sea Component Net Drain Flow
(AF)
Total Measured Drain Flow 80,720
Storm Flow1 ‐227
Adjusted Regulatory Water2 ‐5,968
Valley Sanitary District ‐6,911
Coachella Water Authority ‐3,017
WRP 4 ‐5,835
Kent SeaTech ‐6,086
Net Drain Flow to Salton Sea 52,676
Notes:
AF ‐ acre‐feet
1 – Storm flow is the volume of Coachella Valley Stormwater Channel flow attributed to storm events and is calculated using a base flow separation methodology.
2 – Regulatory water is Canal water in excess of water orders that must be discharged to the drain system (6,984 AF).
Regulatory water is adjusted for amounts not captured by monthly drains measurements because discharges are not
occurring at time of handheld current measurements or are measured through a separate meter than a drain’s dedicated tile drainage meter.
Evapotranspiration (ET)
Prior to agricultural development, water loss through ET was significant above the semi‐perched aquifer in the southeastern portion of the Indio Subbasin. As native landscapes were converted to agriculture, groundwater loss to ET decreased. The installation of the drain system in the 1950s and 1960s lowered groundwater levels in the semi‐perched aquifer, further reducing ET losses. Increased pumping in the 1980s and 1990s may have resulted in further declines in groundwater elevations and ET. The 2022 Alternative Plan Update model was updated to simulate WY 2020‐2021 and ET from the shallow aquifer was simulated as 5,069 AF.
Additionally, a portion of the imported water used for groundwater replenishment and/or disposed as wastewater is assumed to be lost to evaporation. It is estimated that 5,309 AF of water was lost to evaporation from the wastewater disposal ponds and groundwater replenishment spreading basins, assuming a factor of two percent of total volume for groundwater replenishment and wastewater disposal ponds, with the exception of WWR‐GRF where it is assumed a factor of four percent).
7.1.3 Annual Change in Groundwater Storage
Table 7-4 and Figure 7-1 shows inflows to and outflows from the Indio Subbasin and the estimated annual change in groundwater storage for WY 2020‐2021. During periods of high artificial recharge, the change in storage tends to be positive (water in storage increases). In dry years, periods of low artificial recharge, or periods of high pumping, the change in storage is often negative (storage decreases). While WY 2020‐
Indio Subbasin Annual Report
for Water Year 2020-2021 7-8 TODD / W&C
2021 was a dry year, managed artificial recharge continued to replenish the basin. The Indio Subbasin gained 5,954 AF in storage.
Long‐term sustainability is typically assessed based on changes in groundwater storage over a historical period on the order of 10 to 20 years that includes wet and dry periods. Figure 7-2 shows the annual change in groundwater storage from 1970 through WY 2020‐2021 (gray columns). The starting year of 1970 was selected as it is three years before imported water replenishment commenced in the Indio Subbasin. The data used to prepare this figure are based on calendar year until WY 2016‐2017, when data sources were compiled for the water year for the first SGMA Annual Report. WY 2020‐2021 is the first year that the numerical model was used to simulate the change in storage. The model from the 2022 Alternative Plan was updated to reflect conditions through September 2021. Previous years relied on analytical solutions developed to estimate natural processes and long‐term averages.
Figure 7-2 also shows the annual inflows, outflows, groundwater production, and ten‐year and twenty‐ year running‐average change in groundwater storage. As shown on the chart, annual inflows to the Indio Subbasin (blue line) are highly variable with years of high inflows corresponding to wet years when SWP delivery volumes were greater. Higher inflows in the mid‐1980s occurred when MWD commenced large‐ scale advanced water deliveries to the Indio Subbasin. The chart shows that after an extended period of decline, both the ten‐year and twenty‐year running average change in storage have shown upward trends since 2009, and the ten‐year running average has been positive since 2017.
Indio Subbasin Annual Report
for Water Year 2020-2021 7-9 TODD / W&C
Table 7-4 WY 2020-2021 Groundwater Balance in the Indio Subbasin Groundwater Balance Component
WY 2020-2021
Flows
(AF)
Inflows
Infiltration of natural runoff1 23,897
Subsurface inflows from adjacent basins 11,654
Return Flows (Agricultural, Golf Course, and Municipal2) 162,320 Wastewater percolation 4,446
Septic tank percolation 0
Groundwater replenishment 154,848
Total Inflow 357,165
Outflows
Groundwater pumping 285,351
Net drain flow to Salton Sea3 52,676
Evaporative losses4 5,309
Evapotranspiration from the shallow aquifer5 5,069
Subsurface outflow to adjacent basins5 0
Net Salton Sea subsurface flow5 2,806
Total Outflow 351,211
Change in Groundwater Storage +5,954
Notes:
AF ‐ acre‐feet
1 ‐ Net infiltration ‐ Includes stream recharge and mountain front runoff that percolates into the basin.
2 ‐ Includes septic.
3 – Subsurface drain flow from Table 7‐3
4 ‐ Evaporative losses from replenishment and wastewater percolation, two percent from wastewater, Thomas E. Levy and Palm Desert GRF, four percent from WWR‐GRF. 5 ‐ From numerical model updated through WY 2020‐2021.
Indio Subbasin Annual Report
for Water Year 2020-2021 TODD / W&C
Figure 7-2 Historical Annual Change in Groundwater Storage in the Indio Subbasin 7-10
Indio Subbasin Annual Report
for Water Year 2020-2021 7-11 TODD / W&C
While the goal of the CVWMP was to eliminate groundwater overdraft, not to restore the Indio Subbasin to historical conditions, it is worth noting that since 2009 the Indio Subbasin has recovered approximately 845,000 AF of groundwater in storage, or about 45 percent of the cumulative depletion observed from 1970 to 2009. Figure 7-3 shows the cumulative change in storage since 1970. The Indio Subbasin was at its minimum storage in 2009 (with a calculated storage loss of 1,890,000 AF from 1970 to 2009, which represents 6 percent of the estimated storage capacity of the Indio Subbasin). Since 2009, groundwater pumping has decreased by about 25 percent and replenishment activities have increased leading to the observed recovery of groundwater in storage.
The recovery of groundwater storage and the positive trends in the water balance demonstrate the progress being made through implementation of the Alternative Plan.
7.2 CHANGE IN GROUNDWATER ELEVATION MAPS
Figure 7-4 and Figure 7-5 show one‐year and twelve‐year groundwater elevation change maps, respectively. In addition to the main map frame, two separate zoomed‐in frames are included on each figure to show calculated water level changes for the numerous wells in the mid‐valley area and TEL‐GRF vicinity. The change in groundwater elevation is based on the difference between the average groundwater elevations for wells monitored in the Indio Subbasin during WY 2019‐2020 and WY 2020‐ 2021 (one‐year) and WY 2008‐2009 and WY 2020‐2021 (twelve‐year). Current groundwater elevations were compared to WY 2008‐2009 because that water year represented recent historical lows for much of the basin. Figure 7-3 shows the volume of recovery since those historical lows. Careful consideration was taken to ensure that average water level measurements for each well for the respective water years were comparable.
7.2.1 One-Year Change (WY 2019-2020 to WY 2020-2021)
Figure 7-4 shows the one‐year change in average groundwater elevations from WY 2019‐2020 to WY 2020‐2021 for the Indio Subbasin. Groundwater levels in the Indio Subbasin generally increased from WY 2019‐2020 to WY 2020‐2021 in most of the Subbasin. However, in the northwestern area of the Subbasin in the immediate vicinity of the WWR‐GRF, groundwater levels declined compared with WY 2019‐2020, due to reduced replenishment in the latter half of WY 2020‐2021. Groundwater levels also declined somewhat across the eastern portion of the Subbasin but have shown long‐term increasing trends.
Increasing groundwater levels up to 11 feet are seen downgradient of the WWR‐GRF in the vicinity of Palm Springs associated with greater groundwater replenishment at this facility in previous years. In the central portion of the Indio Subbasin from Palm Desert to La Quinta, groundwater levels generally rose with water level changes ranging from about ‐3 to 8.5 feet. Some of the increase in groundwater levels is likely associated with the initiation of replenishment at the PD‐GRF beginning in February 2019. In the vicinity of TEL‐GRF, groundwater levels increased by up to 5 feet, with increased levels observed as far as the Mecca area and adjacent to the Salton Sea. Groundwater level increases reflect the continued benefits of recharge operations at the TEL‐GRF.
Figure 7‐3 Cumulative Change in Groundwater Storage since 1970 Indio Subbasin Annual Report
for Water Year 2020-2021 TODD / W&C TODD / W&C 7-12
Indio Subbasin Annual Report
for Water Year 2020-2021 7-13 TODD / W&C
Figure 7-4 One-Year Change in Groundwater Elevation (WY 2019-2020 - WY 2020-2021)
Indio Subbasin Annual Report
for Water Year 2020-2021 7-14 TODD / W&C
7.2.2 Twelve-Year Change (WY 2008-2009 to WY 2020-2021) Figure 7-5 shows the twelve‐year change in average groundwater elevations from WY 2008‐2009 to WY 2020‐2021 for the Indio Subbasin. Groundwater levels in most of the Indio Subbasin have increased over the past 12 years. The largest groundwater increases are observed downgradient of the WWR‐GRF in the Palm Springs area and in the vicinity of the TEL‐GRF and PD‐GRF, with water level increases of up to about 150 feet directly downgradient of the WWR‐GRF, about 100 feet near the TEL‐GRF, and about 25 feet near the PD‐GRF. In the greater mid‐valley area near Palm Desert, Indian Wells, and La Quinta, groundwater level increases have risen on the order of 20 feet, reflecting the benefits of source substitution, conservation programs, and recharge operations. Some localized declines have occurred northeast of Bermuda Dunes and at the northeastern tip of the Subbasin. Groundwater levels in the southeastern portion of the Indio Subbasin have generally increased, typically between 10 and 45 feet, reflecting storage benefits from replenishment operations at the TEL‐GRF and decreased pumping.
Indio Subbasin Annual Report
for Water Year 2020-2021 7-15 TODD / W&C
Figure 7-5 Ten-Year Change in Groundwater Elevation (WY 2008-2009 - WY 2020-2021)
Indio Subbasin Annual Report
for Water Year 2020-2021 8-1 TODD / W&C
8. DESCRIPTION OF PROGRESS
Building on the original 2002 CVWMP, the 2010 CVWMP Update was adopted in January 2012 with the goal “to reliably meet current and future water demands in a cost‐effective and sustainable manner” and meet the following objectives:
1. Meet current and future water demands with a 10 percent supply buffer.
2. Eliminate long‐term groundwater overdraft.
3. Manage and protect water quality.
4. Comply with state and federal laws and regulations.
5. Manage future costs.
6. Minimize adverse environmental impacts.
In response to adoption of the SGMA in 2014, the Indio Subbasin GSAs collaboratively submitted to DWR the 2010 CVWMP, accompanied by a Bridge Document, as an Alternative to a Groundwater Sustainability Plan (GSP) for the Indio Subbasin that describes how the existing 2010 CVWMP met the requirements of the SGMA. DWR approved the 2010 CVWMP Update as an Alternative Plan in July 2019. SGMA requires plan updates every 5 years. In compliance with SGMA, the GSAs updated and adopted the 2022 Indio Subbasin Water Management Plan Update (2022 Alternative Plan Update) to fulfill that requirement.
This section provides an update of the status of 2022 Alternative Plan Update implementation activities during WY 2020‐2021.
8.1 IMPLEMENTATION OF PROJECTS AND MANAGEMENT ACTIONS
The 2022 Alternative Plan Update identified the following water management strategies to achieve water reliability and resilience through the planning horizon:
• Fully use available Colorado River water supplies
• Support improvement of the long‐term reliability of SWP supplies, including participation in the Delta Conveyance Facility (DCF)
• Continue developing recycled water as a reliable local water supply • Implement source substitution and replenishment for resilience in response to changing conditions and for maintenance of long‐term groundwater supply reliability • Increase water‐use efficiency across all sectors
• Participate in development of the Coachella Valley Salt and Nutrient Management Plan (CV‐ SNMP) to address salt and nutrient management in the Indio Subbasin.
To accomplish this, the GSAs updated and expanded the list of PMAs that support water management within the Subbasin. Thirty PMAs were identified based on priorities set by the GSAs and stakeholders; these represent a wide variety of activities by the four GSAs. Projects are classified into four categories based on project benefits: water conservation, water supply development, source substitution and replenishment, and water quality protection.
The following sections provide a summary of the PMAs included in the 2022 Alternative Plan Update grouped by category. Please refer to the 2022 Alternative Plan Update for more detailed information on the PMAs, and Table 8-1 below for the current status of the PMAs.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-2 TODD / W&C
8.2 WATER CONSERVATION
Water conservation is a major component of overall water management in the Indio Subbasin. As a desert community reliant upon imported water supplies, the Coachella Valley has and will continue to use its water resources efficiently. The 2022 Alternative Plan Update included water conservation efforts for agriculture, urban, and landscaping water demands, and the GSAs continue to expand and strengthen water conservation programs not only through the 2022 Alternative Plan Update, but also through other efforts, such as the Coachella Valley Regional Water Management Group (CVRWMG). This section summarizes existing and proposed urban, agricultural, and golf course water conservation activities in the Coachella Valley.
PMA 1: Urban Water Conservation
For the past three decades, water purveyors have placed a significant focus on urban water conservation as a way of life to address the increasing water demands due to population growth and economic development in the Coachella Valley. Local urban water conservation programs began as early as 1988.
The Indio Subbasin GSAs manage a suite of conservation programs and activities designed to increase efficiency, reduce future water demand, and support fulfillment of the statewide Water Conservation Act.
The Regional Water Conservation Program (Regional Program) has been a cornerstone of water conservation in the Coachella Valley. Implemented in 2013 by the CVRWMG, this multifaceted Regional Program has achieved a significant level of conservation through programs and activities designed to increase efficiency, reduce future water demand, and assist the Coachella Valley in meeting regulatory requirements. The Regional Program funds many of the conservation programs as well as the CV Water Counts ( www.cvwatercounts.com) conservation website.
The demand management programs highlighted in the 2020 Coachella Valley Regional Urban Water Management Plan (2020 RUWMP) (CVWD, et al., 2021c) and refined by the GSAs include but are not limited to landscape plan checks, residential and large landscape smart controller rebates, residential turf conversions, water waste investigations, toilet and clothing washer rebates, commercial and residential plumbing retrofits, and efficient rotating nozzles. The GSAs will continue to seek grant funding to support ongoing delivery and expansion of their conservation programs.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-3 TODD / W&C
The Indio Subbasin GSAs are committed to continued implementation of water conservation programs for both large landscape customers and residential customers in the Subbasin. In addition to rebates and conservation education and outreach, the GSAs continue to implement water use efficient landscape development standards. Additionally, the GSAs will work to implement the 2018 Water Use Efficiency Legislation that will determine preliminary water use objectives for each of the GSAs in 2022.
As part of the 2020 RUWMP, the GSAs have also each developed and adopted a Water Shortage Contingency Plan (WSCP) (CVWD et al., 2021c). Each WSCP included six shortage response levels and associated voluntary and mandatory actions for conservation, depending on the causes, severity, and anticipated duration of the water supply shortage. These response actions have been used effectively in the past and could be implemented as needed, as part of the GSAs’ adaptive management strategy. During WY 2020‐2021 the GSAs were in Shortage Level 1 of their respective WSCPs, which is in place during normal conditions and when less than a 10 percent supply shortage exists. Shortage Level 1 conservation measures currently enacted include:
• Water flow onto adjacent property, non‐irrigated areas, private and public walkways, roadways, parking lots, or parking structures is prohibited.
• Using any water in a fountain or other decorative water feature is prohibited, unless the water recirculates.
• Applying water to driveways, sidewalks, concrete or asphalt is prohibited unless to address immediate health and safety needs. Reasonable pressure washer or water broom use is permitted.
• Spray irrigation of outdoor landscapes during and within 48 hours after rainfall of 0.10 inches is prohibited.
• Using a hose to wash a vehicle, windows, or solar panels is prohibited unless an automatic shut‐ off nozzle or pressure washer is used.
• Broken sprinklers shall be repaired within five business days of notification by agency, and leaks shall be repaired as soon as practical.
• Hotels will provide guests the option of choosing not to have towels and linens laundered daily. • Draining and refilling of private swimming pools is discouraged, unless necessary for health and safety or repairs.
• Overseeding is discouraged.
• Rebates for landscape efficiency are provided.
• Rebates for indoor water use efficiency are provided. • Water use surveys/audits are offered.
PMA 2: Golf Water Conservation
Golf water conservation has been implemented by CVWD since development of the 2002 CVWMP and recognition that demand management was essential to balancing the Indio Subbasin. The CVWD Landscape Ordinance (Ordinance No. 1302.5, last updated July 2020) establishes uniform landscaping standards throughout the Coachella Valley and is one of the few ordinances in the State to establish turf limitations for new and renovated golf courses. CVWD is committed to working with new and existing golf courses to reduce water demands through programs such as irrigation system audits, scheduling irrigation with the best available science, plan checking, inspecting new golf courses for plan check compliance, and monitoring maximum water allowance compliance.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-4 TODD / W&C
In December 2013, CVWD collaborated with the local chapter of the Golf Course Superintendents Association to create a Golf and Water Task Force. In collaboration with the golf course representatives on the Task Force, CVWD launched the golf course rebate program in 2015, after securing a State grant.
CVWD is committed to continued participation in the Task Force.
CVWD’s non‐potable water program currently has 54 golf courses connected to the Mid‐Valley Pipeline (MVP), the Coachella Canal, or the blended delivery systems from WRP‐7 and WRP‐10. The conversion of golf courses from private production wells to non‐potable water reduces groundwater use and maximizes delivery of the region’s imported supplies. CVWD is committed to its ongoing non‐potable water expansion.
DWA serves recycled water to golf courses within its service area where it has been deemed cost effective to connect. Additional courses may be connected when recycled water pipelines are extended to closer proximity. DWA offers incentives to convert grass areas to desert landscape.
PMA 3: Agricultural Water Conservation
Following the 2010 CVWMP Update, CVWD began implementing a variety of agricultural conservation programs, including grower education and training, scientific irrigation scheduling, irrigation upgrades/retrofits, and engineering evaluations. Programs with voluntary grower participation, such as the Extraordinary Conservation Measures programs, have been effective in increasing water use efficiency. CVWD is committed to ongoing implementation of agricultural conservation programs.
CVWD established the Agricultural Water Advisory Group (AWAG) in December 2015 to collaborate with other organizations and educate Valley residents about the agricultural industry’s stewardship of water in the Coachella Valley. CVWD is committed to continued participation in the AWAG.
8.3 WATER SUPPLY DEVELOPMENT
CVWD and DWA continue their efforts to increase reliability and obtain additional water supplies, as they become available through SWP‐related projects (e.g., Delta Conveyance Facility, Sites Reservoir, Lake Perris Seepage) and other exchanges, entitlements, and transfers.
8.3.1 Surface Water
PMA 4: Increased Surface Water Diversion
DWA’s surface water rights for Chino, Snow, Falls Creek, and Whitewater canyon flows total 13,309 AFY.
However, DWA has not always captured all the surface water it has had the right to divert from those sources. DWA plans to divert as much water from those sources as may be available and deliver that diverted surface water to the WWR‐GRF for replenishment into the Indio Subbasin and subsequent extraction for use in DWA’s domestic water supply system. Some of that diverted water is and will continue to be filtered for use in the Snow Creek Village west of Palm Springs.
8.3.2 SWP Water
CVWD and DWA are working with MWD and DWR to both improve the reliability of SWP water and acquire additional supplies. Future SWP projects are outlined below.
PMA 5: Delta Conveyance Facility
Indio Subbasin Annual Report
for Water Year 2020-2021 8-5 TODD / W&C
The Delta Conveyance Facility (DCF) is a project led by DWR to improve SWP reliability by modernizing SWP conveyance facilities in the Delta. The DCF will construct and operate a new tunnel to bypass the existing natural channels that are currently used for SWP conveyance, which are vulnerable to earthquakes, sea level rise, and pumping restrictions. CVWD and DWA both continue to support planning activities associated with DCF.
PMA 6: Lake Perris Dam Seepage Recovery Project
The Lake Perris Dam Seepage Recovery Project is a project led by DWR to collect and distribute SWP water seeping under Lake Perris Dam and deliver the water to MWD in addition to its current allocated Table A water. The proposed project consists of installing an integrated recovery well system that would include up to six new seepage recovery wells and a conveyance pipeline connecting the wells to the CRA. CVWD and DWA both continue to support planning activities for this project.
PMA 7: Sites Reservoir Project
The Sites Reservoir Project is a reservoir in the Sacramento Valley that will capture and store excess water from snowmelt and winter runoff from the Sacramento River for use during dry periods. Water supply and storage capacity will be made available to water purveyors throughout California. CVWD and DWA both continue to support planning activities for this project.
PMA 8: Future Supplemental Water Acquisitions
CVWD has entered into various agreements with Rosedale Rio‐Bravo, Glorious Lands Company, and MWD to deliver supplemental water to the Indio Subbasin. As opportunities arise, CVWD and DWA will continue to make water transfers and purchases.
8.3.3 Potable Reuse
PMA 9: East Valley Reclamation Authority Potable Reuse
In 2013, IWA and VSD formed a Joint Powers Agreement for the East Valley Reclamation Authority (EVRA), with the main objective to augment local water resources through beneficial water reuse. This project involves injection of treated wastewater from the existing VSD WRF for indirect potable reuse. IWA continues to support planning activities for this project.
8.4 SOURCE SUBSTITUTION AND REPLENISHMENT
Source substitution is the delivery of an alternate source of water to users that currently pump groundwater, reducing groundwater extraction and allowing the management of groundwater in storage.
The source substitution projects are presented by water source and location within the Coachella Valley.
8.4.1 Colorado River Water – Non-Potable Water (NPW) Deliveries Historically, Colorado River water (Canal water) was used almost exclusively for agricultural irrigation, with golf course irrigation beginning in 1986. Direct use of Colorado River water now includes agriculture, duck clubs and fish farms, golf courses, and construction water. CVWD is working to expand direct delivery of Colorado River water for agriculture, golf courses, and homeowner’s associations.
PMA 10: Mid‐Valley Pipeline (Canal Only Customers)
Indio Subbasin Annual Report
for Water Year 2020-2021 8-6 TODD / W&C
The MVP is a pipeline distribution system to deliver Canal water to the Mid‐Valley area. Canal water from the MVP is either delivered directly or used to supplement CVWD’s recycled water for golf course and open space irrigation. CVWD continues to pursue the direct connection of golf courses and open spaces that primarily use groundwater for irrigation to the MVP.
PMA 11: Mid‐Canal Storage Project
The Mid‐Canal Storage Project will increase storage along the Coachella Canal by removing the existing embankment between the current lined canal with the original earthen canal section to form a single wide trapezoidal reservoir section. This additional storage will allow CVWD to manage common, but unpredictable, events by providing for capture during excess water events for use during deficit water events. During drought periods, this added backup supply will improve efficient use of water and limit waste.
PMA 12: East Golf Expansion
The East Golf NPW Program currently serves 30.5 golf courses with Canal water. CVWD continues to pursue the East Golf Expansion project to connect additional golf courses in the East Valley to the Coachella Canal.
PMA 13: Oasis Distribution System
The Oasis Distribution System will expand the Canal water delivery system to the Oasis Area to utilize additional Colorado River water and offset groundwater production for agricultural irrigation primarily.
Phase 1 of the project is currently under construction, and CVWD continues to move forward with agricultural connections.
8.4.2 Recycled Water Deliveries
Currently, recycled water production exceeds existing demand during the winter months, and the remaining recycled water is disposed of through onsite percolation basins. The following is a summary of projects to maximize recycled water use by continuing to expand the NPW system and to eliminate land disposal.
PMA 14: WRP‐10 Recycled Water Delivery
The WRP‐10 distribution system delivers NPW to existing customers throughout Indian Wells, Palm Desert, and portions of Rancho Mirage. There are currently 18 customers served by a blend of Canal water and recycled water. CVWD continues to pursue new WRP‐10 NPW connections.
PMA 15: WRP‐7 Tertiary Expansion
CVWD plans to expand its WRP‐7 recycled water production tertiary treatment capacity by 3 mgd to a total capacity of 5.5 mgd (6,150 AFY) to meet anticipated regulatory changes and utilize increases in future wastewater flows. CVWD continues to support planning activities for this tertiary expansion.
PMA 16: Canal Water Pump Station Upgrade
Indio Subbasin Annual Report
for Water Year 2020-2021 8-7 TODD / W&C
The Canal Water Pump Station Upgrade would upgrade the Mile Post (MP) 113.2 Canal water pump station capacity to convey Colorado River supply for blending with WRP‐7 recycled water. CVWD continues to support planning activities for this pump station upgrade.
PMA 17: WRP‐7 Recycled Water Delivery
WRP‐7 delivers NPW to golf courses in the Sun City area. CVWD continues to pursue new WRP‐7 NPW connections.
PMA 18: WRP‐4 Tertiary Expansion & Delivery
CVWD’s tertiary treatment expansion at WRP‐4 will construct tertiary capacity in four phases, establish a recycled water distribution system, and reduce discharges to the CVSC. CVWD continues to work on planning, permitting, and environmental compliance activities for this expansion.
PMA 19: DWA WRP Recycled Water Delivery
DWA will increase deliveries of recycled water consistent with existing customer demands, wastewater flow growth and new cost‐effective connections.
8.4.3 Groundwater Replenishment
Since 1973, CVWD and DWA have replenished the western portion of the Subbasin at the WWR‐GRF with nearly 4 million AF and at the PD‐GRF with a total of 14,836 AF since starting operations in 2019. CVWD has replenished the eastern portion of the Subbasin at TEL‐GRF with about 400,000 AF since full‐scale operations commenced in 2009. The following is a brief summary of projects to continue groundwater replenishment in the Indio Subbasin.
PMA 20: PD‐GRF Expansion
The PD‐GRF Expansion will expand direct replenishment capacity at the PD‐GRF by constructing Phase II of the project which will provide for an additional recharge capacity of up to 15,000 AFY. CVWD continues to operate the PD‐GRF with expanded replenishment volumes as feasible given supply availability and hydraulic capacity.
PMA 21: TEL‐GRF Expansion
The TEL‐GRF Expansion will expand recharge capacity at the TEL‐GRF incrementally through 2025. CVWD continues to evaluate the need to expand the recharge capacity at TEL‐GRF.
PMA 22: WWR‐GRF Operation
The WWR‐GRF has a recharge capacity of more than 300,000 AFY. CVWD and DWA continue to replenish as much SWP Table A water or other imported water at WWR‐GRF as is available annually.
8.5 WATER QUALITY PROTECTION
The Indio Subbasin has variable concentrations of water quality constituents as documented in the 2022 Alternative Plan Update. Below are the PMAs related to water quality that will help protect the groundwater basin for beneficial uses and users and avoid undesirable results.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-8 TODD / W&C
8.5.1 Water Quality Programs and Policies
The following is a list of water quality policies and programs to help protect the Indio Subbasin.
PMA 23: Eliminate Wastewater Percolation
Currently, CVWD’s WRP‐7, WRP‐10, and Palm Springs’ WWTP/DWA’s WRP all discharge to percolation ponds within the Indio Subbasin. The GSAs continue to pursue expansion of recycled water to reduce and eventually eliminate percolation of wastewater into the Indio Subbasin.
PMA 24: Wellhead Treatment
The Wellhead Treatment program assesses the need to expand groundwater treatment facilities to treat additional drinking water wells for arsenic, nitrate, or other constituents of concern. The GSAs continue to monitor the development of new maximum contaminant levels (MCLs) (e.g., hexavalent chromium) to ensure delivered drinking water meets state and federal MCLs established to protect public health.
PMA 25: Small Water System Consolidations
Small water systems, often serving disadvantaged communities (DACs), may face challenges in providing safe, accessible, and affordable water because they may not have adequate resources to support maintenance, operation, and treatment costs. CVWD continues to pursue grant funding and design for several top‐ranked small water system consolidations that were identified in the East Coachella Valley Water Supply Project.
CWA also continues to seek grant funding to consolidate multiple mobile home parks within its service area to address water quality deficiencies identified by the Riverside County Department of Health (DEH).
PMA 26: Septic to Sewer Conversions
Septic systems are a documented source of nitrate to the groundwater basin. CVWD continues to pursue grant funding and design for several septic‐to‐sewer conversions to improve groundwater quality and sanitation within small communities in the East Valley.
8.5.2 Coachella Valley Salt and Nutrient Management Plan (CV-SNMP) In 2020 and 2021, the CV‐SNMP agencies – which include CVWD, Coachella Sanitary District, City of Palm Springs, CWA, DWA, IWA, MSWD, Myoma Dunes Mutual Water Company, and VSD – prepared a CV‐SNMP Groundwater Monitoring Program Workplan and a CV‐SNMP Development Workplan to guide the monitoring and update of the 2015 CV‐SNMP.
PMA 27: Implement CV‐SNMP Groundwater Monitoring Program Workplan The GSAs, along with the other CV‐SNMP partners, began implementing the CV-SNMP Groundwater Monitoring Program Workplan approved by the RWQCB in February 2021 and outlining an expanded groundwater monitoring program.
PMA 28: Implement CV‐SNMP Development Workplan
The GSAs, along with the other CV‐SNMP partners, will begin implementing the CV-SNMP Development Workplan approved by the RWQCB in October 2021 and outlining a scope of work for updating the CV‐ SNMP in accordance with the Recycled Water Policy.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-9 TODD / W&C
PMA 29: Colorado River Basin Salinity Control Forum
The Salinity Forum, which is a cooperative effort involving federal, state, and local agencies, includes projects that remove salt tonnage. This will be accomplished principally by reducing the salt contributions to the Colorado River from existing sources and minimizing future increases in salt load caused by human activities. CVWD will continue to support and participate in Salinity Forum efforts.
PMA 30: Source Water Protection
Well management programs are required to ensure that existing and future wells do not impact the usability of the groundwater resource. CVWD continues to implement the Leaking Artesian Well Rebate Program to educate and work with well owners to properly control artesian wells.
8.6 CURRENT IMPLEMENTATION STATUS
The PMAs are identified and described in Table 11‐3 of the 2022 Alternative Plan Update. The GSAs have continued efforts to advance the PMAs to maintain the Indio Subbasin in sustainable conditions, able to meet Plan Area water demands, and groundwater levels and quality that avoid undesirable results. With continued implementation of these PMAs, the GSAs are anticipated to meet their water management goals and comply effectively with SGMA. A revised version of Table 11‐3, with the current updated status of each PMA, is presented as Table 8-1.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-10 TODD / W&C
Table 8-1 WY 2020-2021 CVWMP Implementation Status Update PMA Name Project Proponent(s) Activity Name Activity Description 2021 Status 2022 Planned Activities Water
Conservation
PMA 1: Urban
Water
Conservation
CVWD, DWA, IWA,
CWA
Outreach/Education and CV
Water Counts
Continue to implement public
information programs, including
CV Water Counts. Educate the
public on conservation programs
being planned and/or
implemented, as well as
educational tips that customers
can use to lower their water
usage. Includes publications,
demonstration gardens,
workshops, community events,
website, social media, and a
school education program.
Increased messaging
regarding drought water
efficiency. In process of
planning and designing
two new demonstration
gardens. Continued
planned outreach
workshops & community
events.
Complete one demonstration
garden. CVWD and DWA
will complete demonstration
gardens in their respective
service areas. Design and
begin construction on the
other demonstration garden.
Conduct additional grass
removal programs. Create a
new, regional DAC-oriented
grass removal and device
upgrade program using state
grant funds. Expand public
outreach.
Host a Water Academy with
various panelists to educate
interested community
members about water
resources and conservation.
CVWD, DWA, IWA,
CWA
Water Shortage Contingency
Plan (WSCP)
Implement WSCP as needed in
response to drought conditions.
Implement supply augmentation,
demand reduction, and
operational changes as needed
to meet declared shortage level.
Adopted updated Water
Shortage Contingency
Plans (WSCP). Updated
Regional Urban Water
Management Plan
(RUWMP).
Continue to monitor water
supplies and operational
changes and will declare
shortage levels if
appropriate.
CVWD, DWA, IWA,
CWA Grant Funding
Pursue grant funding to fund
urban water conservation
programs at a higher level, as
needed.
Awarded grant funding for
enhanced rebates and
expanded demonstration
garden.
Utilize Proposition 1 Round 1
funds to further
demonstration gardens and
begin construction. Pursue
funding through the grass
removal projects. Secure
2021 Urban and Multibenefit
Drought Relief Grant
Program URC Set-aside to
implement a rebate program
targeting DAC communities.
CVWD, DWA, IWA,
CWA Conservation Study
Conduct a Conservation Study,
including a detailed analysis of
market saturation. Quantify
potential savings from
implementing current programs,
relative cost on an AF basis, and
potential for future savings.
Began developing scope
of work. Submitted study
concept to the University
of California, Santa
Barbara Bren School of
Environmental Science &
Management as potential
Master’s group project.
Pursue grant funding.
Complete scope of work and
initiate study.
CVWD, DWA, IWA,
CWA
Update and Implement Water
Rates
Update Replenishment
Assessment Charge and all
water and sewer rates as
necessary per cost of service
studies. Consider tiered rates.
Implement updated rates.
CVWD completed 5-year
cost of service studies
(COSS) for Canal and
Replenishment
Assessment Charge rates
and implemented
updated rates for Fiscal
Year 2022.
IWA completed 10-year
Long Range Financial
Plan review.
CVWD will conduct a
Sanitation cost of service
study and consider potential
rate changes for Fiscal Year
2023.
DWA to complete a cost of
service study for potable and
non-potable rates.
IWA to conduct water rate
study.
CVWD, DWA, IWA,
CWA Leak Detection/Water Loss
Continue to implement water loss
reduction programs and
practices.
Continued monitoring of
water loss improved
water loss tracking and
improved proactive meter
replacement.
Determine water loss target
as part of overall water use
objective.
Desert Water Agency will
seek to augment budget to
cover a more aggressive
pipeline replacement
program.
CVWD, IWA, CWA Implement Landscape
Ordinance
Continue to implement MWELO,
including plan checks.
Revised Landscape
Ordinance in 2020 to
comply with special
landscaping
requirements.
Continue to comply with
State requirements and
implement Landscape
Ordinance 1302.5.
CVWD, DWA Water Audits
Continue to implement Large
Landscape Irrigation Audit
Program to assist users in
maximizing the efficient
operation of their irrigation
system by measuring
performance, generating
Conducted over 1,650
water audits.
Continue to offer audits and
commit to increasing
outreach.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-11 TODD / W&C
PMA Name Project Proponent(s) Activity Name Activity Description 2021 Status 2022 Planned Activities irrigation schedules and
recommending improvement
actions.
CVWD Professional Landscaper
Training
Continue to host a Landscaper
Certification Program for
professional landscapers that
focuses on water use efficiency.
Hosted Qualified Water
Efficient Landscaper
(QWEL) training.
Consider hosting another
QWEL training and other in-
house workshops.
CVWD, DWA, IWA Water Waste Program/Patrols
Actively patrol the service area
for water waste violations.
Unresolved issues result in
increasing fines to customers.
Provide platform to receive water
waste reports.
Increased patrol efforts.
Worked with CVAG CV
Link project and other
communities with known
water waste issues.
Review and follow up with
customers on reported
water waste instances.
Continue efforts and
increase in response to the
drought as necessary.
CVWD, DWA, IWA,
CWA Indoor Rebates
Implement indoor rebate
programs, designed to assist
homeowners and commercial
customers who want to reduce
their water usage by upgrading
or replacing devices, or installing
new technology to improve
efficiency.
Since program inception,
2 pilot programs
transitioned into
permanent programs.
Issued rebates for 37
residential hot water
recirculating pumps and
263 residential high
efficiency washing
machines.
Research potential for new
programs and continue to
promote participation in
existing programs.
Leverage state grant funds
for regional DAC program for
toilets and washing
machines.
CVWD, DWA, IWA,
CWA Landscape/Outdoor Rebates
Implement landscape/outdoors
rebates, designed to assist
homeowners, HOA, and
commercial customers who want
to reduce their outdoor water
usage by converting their lawn to
desert-friendly landscaping,
installing smart irrigation
controllers, or improving the
efficiency of their systems.
Reducing outdoor usage is the
best way to meet a monthly
water budget.
Since program inception,
20.6 million square feet of
turf converted to desert
landscape. Issued 381
smart controller rebates
for residential and
commercial customers.
Continue to promote
participation in landscape
and outdoor rebate
programs.
Leverage state grant funds
for regional DAC program for
grass removal.
PMA 2: Golf Water
Conservation CVWD Golf & Water Task Force
Meetings
Continue to meet bi-monthly, or
as needed, with Golf & Water
Task Force to discuss
conservation programs that
support golf courses.
Met regularly in virtual
format.
Continue to meet regularly,
potentially in-person.
CVWD Model Golf Course Water
Budgets
Continue to create model water
budgets for area golf courses
and provide that information to
the courses. While the courses
are not billed according to those
budgets (see water budget
based tiered rates below), they
can use the budget as a tool to
determine their efficiency rates.
Mapped courses and
provided model water
budgets upon request.
Updated GIS software to
provide improved
mapping.
Continue to offer this service
upon request.
CVWD Golf Course Education
Programs
Develop golf course incentive
programs that provide education
for golf course managers on
water use efficiency.
Discussed potential
programs at the Golf &
Water Task Force
meetings. Promoted
University California,
Riverside turf grass &
landscape research field
day.
Continue to identify potential
golf course incentive
programs and implement as
needed.
CVWD, DWA Grant Funding
Secure grant funding as
available to create incentive
programs for water use efficiency
such as lake liner programs,
irrigation efficiency programs, or
turf removal rebates.
Researched potential
grants at Golf & Water
Task Force meetings.
Continue to seek grant
funding.
CVWD Conservation Study
Complete a Conservation Study
to better quantify potential
savings from implementing
current or proposed golf
conservation programs, relative
cost on an AF basis, and
potential for future savings as
needed.
No action.
Consider needs and scope
of work to conduct
evaluation.
PMA 3: Agricultural
Water Conservation CVWD AWAG Meetings
Continue to meet bi-annually with
AWAG to discuss any updates
that impact the agricultural
community and receive input
from local farmers.
Held two virtual meetings. Continue to meet bi-
annually, possibly in-person.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-12 TODD / W&C
PMA Name Project Proponent(s) Activity Name Activity Description 2021 Status 2022 Planned Activities CVWD Agricultural Efficiency
Work with other agencies and
organizations through AWAG to
identify projects and programs
that could assist farmers,
including small farmers, on
improving water use efficiency.
Promoted programs and
events that would be
beneficial to farmers.
Continue to promote
programs and events to
assist farmers in water use
efficiency improvements.
CVWD Agricultural Resource Page
Maintain agriculture page on
CVWD website with links to
resources such as agricultural
articles, grants and rebates,
meetings and groups, education,
and trainings.
Regularly updated
website as necessary.
Continue to share relevant
information on website.
CVWD Grant Funding
Secure grant funding to create
incentive programs for water use
efficiency such as flood-to-drip
rebates, soil sensor programs, or
irrigation fixture upgrades.
Researched potential
grant funding
opportunities.
Continue to seek grant
funding.
CVWD Conservation Study
Complete a Conservation Study
to better quantify potential
savings from implementing
current or AWAG identified
programs, relative cost on an AF
basis, and potential for future
savings as needed.
No action.
Consider needs and scope
of work to conduct
evaluation.
Water Supply
Development
PMA 4: Increased
Surface Water Diversion DWA Surface Water Diversions
Increase surface water
diversions for replenishment at
WWR- GRF for use in its
domestic water supply system.
Installed meter for Snow
Creek and Falls Creek
surface water diversions
to WWR-GRF.
Diversion valve automation
to maximize diversion flows.
PMA 5: Delta
Conveyance
Facility
CVWD, DWA DCF Deliveries
Continue participation in DCF,
anticipated to increase SWP
reliability from 45% to ~58%
starting in 2041; restores
approximately 26,500 AFY in
SWP deliveries allocated
between 60% Table A and 40%
Article 21
DWR and Delta
Conveyance Design and
Construction Authority
began preparing public
draft EIR and began
application processes for
Incidental Take Permit
and Biological
Assessment.
DWR and Delta Conveyance
Design and Construction
Authority will complete final
EIR, Incidental Take Permit
and Biological Assessment.
CVWD and DWA will request
financial commitment from
Boards for the next 2 years.
DWR will begin application
processes for Water Rights
and other Environmental
Permits
PMA 6: Lake Perris
Seepage
CVWD, DWA Lake Perris Seepage
Continue participation in Lake
Perris Seepage, which installs a
series of five pumps placed
down-gradient from the face of
the Lake Perris Dam that will
pump seepage from the lake into
a collection pipeline that
discharges directly into MWD’s
Colorado River Aqueduct.
Anticipated 2025-2045 per 2019
Terms Sheet, 2,753 AFY
DWR and MWD
completed final EIR and
geological investigations
and began final design.
CVWD Board approved
entering agreement with
DWR for participation in
Environmental Analysis
and Planning and
Preliminary Design.
DWR and MWD will
complete final design.
PMA 7: Sites
Reservoir
CVWD, DWA Sites Reservoir
Continue participation in Sites
Reservoir, which captures and
stores stormwater flows from the
Sacramento River for release in
dry years. Deliveries at 11,550
AFY (participation amount with
assumed 30% conveyance loss)
beginning in 2035.
Sites Project Authority led
preparation of public draft
EIR, and began
application processes for
Water Rights, Clean
Water Act, Incidental
Take Permit, Biological
Assessment, Section 106
Programmatic
Agreement.
Sites Project Authority will
begin Preliminary
Engineering; advance
Engineering of Feature
Encroachments; complete
final EIR; determine overall
project schedule and
delivery strategy; execute
Final Operating Agreement;
begin developing a Land
Acquisition Master Plan; and
begin securing funding.
PMA 8: Future
Supplemental
Water Acquisitions CVWD, DWA Supplemental Water
Enter into new agreements for
Supplemental water, as available
from SWP or Colorado River.
No activity. No activity.
PMA 9: EVRA
Potable Reuse
IWA Implement Groundwater
Model and PDR
Implement groundwater model
and begin regulatory and
stakeholder engagement. FY
2021-2023. Preliminary Design
FY 2023-2024.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-13 TODD / W&C
PMA Name Project Proponent(s) Activity Name Activity Description 2021 Status 2022 Planned Activities Source
Substitution and Replenishment
PMA 10: Mid-Valley
Pipeline (Canal Only Customers)
CVWD
FY 32-40 Mid-Valley Pipeline
Golf Course
Connections/Design &
Construction
Seek Clean Water State
Revolving Fund (CWSRF) and
Water Infrastructure
Improvements for the Nation Act
(WIIN) grant funding support to
design and construct mid-valley
pipeline canal connections to
Indian Wells Country Club, El
Dorado Country Club, La Rocca,
Marrakesh Country Club,
Shadow Mountain, Vintage
Country Club, Morningside
Country Club, Chaparral Country
Club, Date Palm Country Club,
Rancho Las Palmas, Monterrey
Country Club, Thunderbird
Country Club, and Porcupine
Ridge. The projects will expand
canal delivery for landscape
irrigation to area golf courses.
No activity.
No activity planned. These
connections are planned for
Fiscal Years 2032 to 2040.
PMA 11: East Golf
Expansion CVWD East Golf Expansion
Deliver Canal water to 5
additional golf courses in East
Valley.
Awarded construction
contract to connect
Madison Club Golf
Course.
Complete construction of
new meter connection to
Madison Club golf course.
PMA 11: Mid-Canal
Storage Project CVWD Design and Environmental
Develop plans, specifications,
and engineering (PS&E), along
with environmental permitting
support, for the project.
Began design and
environmental
documentation.
Complete design and
environmental
documentation.
CVWD Mid-Canal Storage
Construction
Construct a wide trapezoidal
reservoir section within the
Coachella Canal to store peak
flows, improve water efficiency,
and limit water waste
Applied for WaterSMART
Drought and Water and
Energy Efficiency grants.
Receive funding decisions
from WaterSMART Drought
and Water and Energy
Efficiency Grant applications.
Begin construction.
PMA 12: Oasis
Distribution
System CVWD Oasis Distribution System
Expand the Canal water delivery
system to the Oasis area.
Substitute groundwater
production with Canal water for
agricultural irrigation and other
non-potable landscape irrigation.
Oasis In-Lieu Recharge,
Phase 2 under
construction.
Complete Phase 2
construction.
PMA 13: WRP-10
Recycled Water
Delivery
CVWD
FY 18 Non-Potable Water
Golf Course
Connections/Construction
Seek CWSRF and WIIN grant
funding support to construct non-
potable water connections to
Oasis Country Club, Woodhaven
Country Club, Palm Desert
Resort Country Club, Bermuda
Dunes Country Club, Marriott
Desert Springs, Marriott Shadow
Ridge, Emerald Desert, and T1
Pump Station. The project will
expand non-potable water
landscape irrigation to area golf
courses.
Construction contracts
awarded for these golf
course connections.
Complete construction.
CVWD
FY 21 Non-Potable Water
Golf Course
Connections/Design &
Construction
Seek CWSRF and WIIN grant
funding support to design and
construct non-potable water
connections to Suncrest Country
Club, Rancho Mirage Country
Club, Annenberg, Tamarisk
Country Club, Tri-Palm Country
Club, Jack Ivey Ranch, Palm
Royale Country Club, Southwest
Community Church, and Indian
Wells Tennis Garden. The
project will expand non-potable
water landscape irrigation to area
golf courses.
Offsite design and
environmental reviews
completed for these golf
course connections.
Applications to seek
CWSRF financing are in
progress.
Projects will be advertised
for bid pending receipt of
CWSRF financing.
CVWD
FY 22 Non-Potable Water
Golf Course
Connections/Design &
Construction
Seek CWSRF and WIIN grant
funding support to design and
construct upsizing improvements
to the existing Non-Potable
Water (NPW) pipelines,
converting Indian Ridge Country
Club to lake delivery, and non-
potable water connections to
Desert Island and Springs
Country Club. The project will
expand non-potable water
landscape irrigation to area golf
courses.
No activity.
Prepare a Request for
Proposal (RFP) to initiate
design of these non-potable
water connections.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-14 TODD / W&C
PMA Name Project Proponent(s) Activity Name Activity Description 2021 Status 2022 Planned Activities CVWD
FY 25 Non-Potable Water
Golf Course
Connections/Design &
Construction
Seek CWSRF and WIIN grant
funding support to design and
construct non-potable water
connections to Mission Hills
Country Club, Westin Hills,
Outdoor Resort, and Forest
Lawn. The project will expand
non-potable water landscape
irrigation to area golf courses.
No activity.
No activity planned. These
are future non-potable water
connections.
CVWD
Future Non-Potable Water
Golf Course
Connections/Design &
Construction
These projects are planned for
FY26 and beyond depending on
new golf courses and residential
tracts.
No activity.
No activity planned. These
are future non-potable water
connections.
PMA 14: WRP-7 Tertiary Expansion CVWD
FY 21 - WRP 7 Tertiary
Treatment Expansion and
MP113.2 Pump Station
Upgrade/Construction.
Seek CWSRF and WIIN grant
funding support to construct an
expansion of the tertiary system
by 2.5 mgd for a total capacity of
5.0 mgd, add a 5-million-gallon
tertiary water storage bladder,
repurpose a land disposal pond
to accept secondary effluent for
pretreatment, and upgrade the
capacity of the MP 113.2 canal
water pump station. The project
will expand non-potable water
landscape irrigation to area golf
courses.
Continued to work on the
preliminary design for the
tertiary expansion project.
Complete design, initiate
environmental
documentation and submit
application for CWSRF
funding.
PMA 15: Canal
Water Pump Station Upgrade CVWD Canal Water Pump Station Upgrade
Construct pump station to
convey Canal water. Complete
design of MP 113.2 Canal Water
Pump Station upgrade in 2022.
Complete construction in 2026.
Continued to prepare the
preliminary design for the
canal water upgrade
project.
Complete design, initiate
environmental
documentation and submit
application for CWSRF
funding.
CVWD
FY21 - WRP 7 Tertiary
Treatment Expansion and
MP113.2 Pump Station
Upgrade/Construction
Seek CWSRF and WIIN grant
funding support to construct a
capacity upgrade to the existing
pump Station at MP 113.2 canal
water pump station. The
additional pump station capacity
will expand non-potable water
landscape irrigation to area golf
courses.
Continued to prepare the
preliminary design for the
canal water upgrade
project.
Complete design, initiate
environmental
documentation and submit
application for CWSRF
funding.
PMA 16: WRP-7
Recycled Water Delivery
CVWD
FY 22 Non-Potable Water
Golf Course
Connections/Design &
Construction
Seek CWSRF and WIIN grant
funding support to design and
construct non-potable water
connections to Talavera
Residential Community, Young's
Family Farms, and Shadow Hills
High School, and Shadow Hills
North Golf Course. The project
will expand non-potable water
landscape irrigation to area golf
courses.
Completed design plans
for Young’s Family
Farms.
Initiate the design for the
other non-potable water
connections and submit
applications for CWSRF
funding.
PMA 17: WRP-4 Tertiary Expansion
& Delivery
CVWD
FY 22 WRP 4 – Phase 1A
Tertiary Expansion and New
Customer
Connections/Construction
This project includes seeking
CWSRF and WIIN grant funding
support to construct an
expansion of the tertiary system
by 2.5 mgd and connect three
new irrigation farm customers
including Grimmway Farms,
West Coast Turf, and Ocean
Mist. The project will expand
non-potable water to area
irrigation customers.
Continued to prepare the
preliminary design for the
tertiary expansion project.
Complete design and initiate
environmental
documentation.
CVWD
FY 26 WRP 4 – Phase 1B
Tertiary Expansion and New
Customer
Connections/Design &
Construction
This project includes seeking
CWSRF and WIIN grant funding
support to construct an
expansion of the tertiary system
by 7.5 mgd for a total capacity of
10 mgd and connect new
irrigation farm customers. The
project will expand non-potable
water to area irrigation
customers.
No activity. No activity planned. This is a
future expansion project.
PMA 18: DWA WRP
Recycled Water
Delivery DWA DWA WRP Recycled Water
Increase deliveries of recycled
water in DWA's service area
consistent with existing customer
demands, wastewater flow
growth and new cost-effective
connections.
Discussed connection
with potential customers.
Explore cost-effective
connections.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-15 TODD / W&C
PMA Name Project Proponent(s) Activity Name Activity Description 2021 Status 2022 Planned Activities PMA 19: PD-GRF
Expansion
CVWD
FY 22 - Palm Desert
Groundwater Replenishment
Facility - Phase II
Construct three groundwater
replenishment basins to receive
Colorado River water within the
Whitewater River Stormwater
Channel. A groundwater
replenishment facility will serve
to help mitigate historical
groundwater level declines within
the West Whitewater River Sub-
basin Area. Approximately an
additional 15,000 AFY of
Colorado River water will be
delivered via the adjacent Mid-
Valley Pipeline, for a total
replenishment in the near vicinity
of 25,000 AFY.
Completed Final EIR,
design, hydrologic
studies, technical
appendices. CDFW 1600
permit executed.
Finalize USACE 404 permit
application materials,
application review,
coordinate permit issuance.
RWQCB 401 Water Quality
certification permit
processing, coordination,
and issuance.
PMA 20: TEL-GRF Expansion CVWD TEL-GRF Expansion
Expand recharge capacity at the
TEL-GRF from 37,000 to 40,000
AF.
No activity None planned in 2022
PMA 21: WWR-GRF Operation
CVWD, DWA Maximize
WWR-GRF Replenishment
Continued operation of WWR-
GRF at maximum available
replenishment water. If additional
SWP exchange water can be
acquired, increase
replenishment.
BLM easement for facility
in progress. BLM
prepared a draft EIS and
received public
comments. CVWD
prepared a draft EIR and
received public
comments.
BLM will schedule to file
Record of Decision for
EIS. Pending filing, take EIR
to CVWD Board for
certification. BLM to
determine issuing CVWD a
Right-of-Way grant.
Water Quality Protection
PMA 22: Eliminate Wastewater
Percolation
CVWD, CWA, DWA Eliminate Wastewater
Percolation
Eliminate wastewater
percolation. Recycle water that
would have been percolated to
be protective of water quality.
Design in progress for
WRP 4 Phase I
Improvements NPW
Project, WRP 7 Recycled
Water Expansion Project,
and WRP 10 Tertiary
Filter Upgrade Project.
Begin/continue design for
WRP 4 Phase I
Improvements NPW Project,
WRP 7 Recycled Water
Expansion, WRP 10 Tertiary
Filter Upgrade, as well as
Indian Wells Tennis, and
Garden, Marriott Desert
Springs North Course,
Marriott Shadow Ridge,
Desert Island Country Club,
Emerald Desert, Young’s
Farmland, Springs Country
Club, and Talavera NPW
Connection Projects.
Construction in progress
for WRP 10 T1 Pump
Station Replacement, as
well as Oasis Country
Club, Woodhaven
Country Club, Palm
Desert Resort Country
Club, and Bermuda
Dunes Country Club
NPW Connection
Projects.
Begin/continue construction
for WRP 10 T1 Pump Station
Replacement, as well as
Jack Ivey Ranch, Tri-Palms
Country Club, Palm Royale
Country Club, Southwest
Community Church,
Suncrest Country Club,
Annenberg Golf Club,
Rancho Mirage Country
Club, and Tamarisk Country
Club NPW Connection
Projects.
Completed WRP 10
Secondary Effluent Pump
Station and Storage
Ponds.
Complete construction for
Oasis Country Club,
Woodhaven Country Club,
Palm Desert Resort Country
Club, and Bermuda Dunes
Country Club NPW
Connection Projects.
PMA 23: Wellhead Treatment CVWD, DWA, IWA,
CWA Wellhead Treatment
Assess the need to expand
groundwater treatment facilities
to treat additional wells in the
future for arsenic, nitrate, or
other constituents.
Monitoring developments
on new hexavalent
chromium MCL.
Continue to assess needs
IWA Hexavalent Chromium
Wellhead Treatment
Pending Cr6 MCL, upgrade resin
at existing IX treatment plants
(FY 2021-22). Begin design and
construction of new wellhead
treatment facilities (FY 2022-26)
PMA 24: Small
Water System
Consolidations
CVWD, DWA, IWA,
CWA
Small Water System
Consolidations
Extend urban water service to
small water systems (e.g., mobile
home/RV park communities) with
deficient infrastructure and poor
water quality. Implement
consolidations as grant funding
becomes available.
Continued to participate
in Disadvantaged
Community Infrastructure
Task Force meetings and
identify grant funding
opportunities and
projects.
Continue to participate in
Disadvantaged Community
Infrastructure Task Force
meetings and identify grant
funding opportunities and
projects.
Pursue 2021 Urban and
Multibenefit Drought Relief
Grant Program URC Set-
aside for Valley View Mobile
Home Park Water
Consolidation Project.
Indio Subbasin Annual Report
for Water Year 2020-2021 8-16 TODD / W&C
PMA Name Project Proponent(s) Activity Name Activity Description 2021 Status 2022 Planned Activities
CVWD Saint Anthony Water
Consolidation Project
Seek grant funding to design and
construct a new domestic water
pipeline along Avenue 66 and
adjacent roadways to serve the
Saint Anthony area with clean,
safe drinking water.
Continued to prepare the
grant funding applications
and finish the design
plans for portions of this
project.
Receive the Grant Funding
Agreement from the State
Water Board and initiate
construction on a portion of
this project.
CVWD Valley View Water
Consolidation Project
Seek grant funding to design and
construct a new domestic water
pipeline along Airport Blvd and
adjacent roadways to serve the
Valley View area with clean, safe
drinking water.
Continued to prepare the
grant funding applications
and finish the
environmental
documentation for a
portion of this project.
Complete the environmental
documentation for a portion
of this project and initiate
design pending receipt of
grant funds.
PMA 25: Septic to Sewer Conversions
CVWD, DWA, IWA,
CWA Septic to Sewer Conversions
Seek USDA, CWSRF, and WIIN
grant funding support to design
and construct septic-to-
centralized sewer systems and
expand service to DACs.
Implement conversions as grant
funding becomes available.
Continued to participate
in Disadvantaged
Community Infrastructure
Task Force meetings and
identify grant funding
opportunities and
projects.
CVWD staff will continue to
participate in Disadvantaged
Community Infrastructure
Task Force meetings and
identify grant funding
opportunities and projects.
CVWD Monroe Trunk Sewer
Seek grant funding to design and
construct a new sewer pipeline
along Monroe Street from
Avenue 62 to Avenue 64 to
expand CVWD's service area to
the tribal residential
neighborhood within the
intersection of Avenue 64 and
Monroe.
CVWD received notice
from USDA that they will
fund this project pending
CVWD compliance with
letter of conditions.
Bid the project for
construction upon approval
that CVWD has met the
letter of conditions from
USDA and received a
funding agreement.
CVWD Avenue 66 Trunk Sewer
Seek grant funding to design and
construct a new sewer pipeline
along Avenue 66 and Harrison to
expand CVWD's service area to
the Torres-Martinez Coachella
center, Sunbird Mobile Home
Park, and residential
neighborhood within Middleton
Road.
Design and
environmental
documentation
completed. Grant funding
application currently in
process with CWSRF.
Receive grant funding
agreement and bid the
project for construction.
CVWD Airport Blvd Sewer
Consolidation Project
Seek grant funding to design and
construct a new sewer collection
system (gravity sewer pipelines
and lift stations), along Desert
Cactus Dr, Ave 57th, Fillmore St
and Airport Blvd.
Worked with funding
agencies to determine
available funding. CVWD
Board certified the
environmental document.
Finalize funding application
with the State Water Board
and receive a funding
agreement for design.
PMA 26: Implement
CV-SNMP Groundwater
Monitoring Program Workplan
CVWD, DWA, IWA,
CWA
Implement CV-SNMP
Groundwater Monitoring
Program Workplan
Implement the CV-SNMP
Groundwater Monitoring
Program Workplan approved by
the RWQCB to expand and
improve the region’s
groundwater monitoring system
for water quality.
Groundwater Monitoring
Program Workplan
approved by Regional
Board. Initiated first
phase of monitoring.
Applied for DWR
Technical Support
Services and Coachella
Valley Mountains
Conservancy grant to
install monitoring wells to
fill gaps in network.
Submit first annual progress
report to Regional Board.
Continue monitoring. Begin
installing monitoring wells to
fill network gaps.
PMA 27: Implement CV-SNMP
Development Workplan
CVWD, DWA, IWA,
CWA
Implement CV-SNMP
Development Workplan
Develop a compliant CV-SNMP
per the SNMP Development
Workplan submitted to the
RWQCB.
Development Workplan
accepted by Regional
Board. Initiated first
workplan task to select
consultants to prepare
updated CV-SNMP.
Select consultants to
prepare updated CV-SNMP
and continue workplan
implementation.
PMA 28: Colorado River Basin Salinity
Control Forum CVWD, DWA Colorado River Salinity Forum
Support implementation of
Colorado River Salinity Forum
projects through participation and
comments on Forum activities.
Submitted comments on
the Public Review Draft of
the 2020 Review, Water
Quality Standards for
Salinity, Colorado River
System
Continue to support Salinity
Forum through participation
and comments as
opportunities arise.
PMA 29: Source
Water Protection CVWD, DWA Abandoned well management
program
Continue cooperating with
Riverside County DEH to identify
and cap/destroy unused wells.
Ongoing
Continue to cooperate and
coordinate with Riverside
County DEH as opportunities
arise.
CVWD Leaking artesian well rebate
program
Continue implementing CVWD's
leaking artesian well rebate
program.
Included $50,000 in
Fiscal Year 2022 budget
for leaking artesian well
repairs and destructions.
Continue implementing
CVWD's leaking artesian
well rebate program.
CVWD Well management rebate
programs
Continue to secure grant funding
when available to supplement
leaking artesian well rebate
program and fund proper
abandonment/destruction of
unused wells.
No activity.
Pursue grant funding when
eligible opportunities are
identified.
Indio Subbasin Annual Report
for Water Year 2020-2021 9-1 TODD / W&C
9. REFERENCES
California Department of Water Resources (DWR). 1964. California Department of Water Resources Bulletin 108—Coachella Valley Investigation. July. Sacramento, California. Available:
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=8773 .
DWR. 1979. Coachella Valley Area Well Standards Investigation: Los Angeles. California Department of Water Resources, Southern District.
DWR. 2016. California’s Groundwater, Bulletin 118 Interim Update 2016. Received December 2020, Available:
https://water.ca.gov/‐ /media/DWR‐Website/Web‐Pages/Programs/Groundwater‐ Management/Bulletin‐118/Files/B118‐Interim‐Update‐2016_ay_19.pdf.
Coachella Valley Water District (CVWD) 2002a. Coachella Valley Final Water Management Plan.
September 2002, prepared by MWH and WaterConsult. Available:
https://www.cvwd.org/ArchiveCenter/ViewFile/Item/358 .
CVWD. 2002b. Final Program Environmental Impact Report, Coachella Valley Water Management Plan, prepared by MWH.
CVWD. 2012a. Coachella Valley Water Management Plan 2010 Update. January. Coachella, California.
Final. Prepared by MWH. Available: https://cvwd.org/ArchiveCenter/ViewFile/Item/317 .
CVWD. 2012b. Final Subsequent Program Environmental Impact Report, for the Coachella Valley Water Management Plan 2010 Update, prepared by MWH.
CVWD, 2014. 2014 Status Report on the 2010 Update. Prepared by MWH.
CVWD. 2017. Engineer’s Report on Water Supply and Replenishment Assessment for the Mission Creek Subbasin Area of Benefit, West Whitewater River Subbasin Area of Benefit, and East Whitewater River Subbasin Area of Benefit 2017-2018. April. Palm Desert, California. Available:
https://www.cvwd.org/ArchiveCenter/ViewFile/Item/574 .
CVWD. 2018a. Engineer’s Report on Water Supply and Replenishment Assessment for the Mission Creek Subbasin Area of Benefit, West Whitewater River Subbasin Area of Benefit, and East Whitewater River Subbasin Area of Benefit 2017-2018, April 2018.
CVWD. 2018b. Non-Potable Water System: WRP-10 NPW System Expansion, Final Draft, prepared by Akel Engineering Group, Inc., June 2018.
CVWD. 2019a. Amended and Restated Agreement Between the Metropolitan Water District of Southern California, Coachella Valley Water District, and Desert Water Agency for the Exchange and Advance Delivery of Water.
CVWD. 2019b. Second Amendment to Delivery and Exchange Agreement Between Metropolitan and Coachella for 35,000 Acre-Feet.
CVWD. 2020. Sanitation Master Plan Update, Volume 3 General. April 2020. Prepared by CDM Smith.
Indio Subbasin Annual Report
for Water Year 2020-2021 9-2 TODD / W&C
CVWD, Desert Water Agency (DWA), and Mission Springs Water District (MSWD). 2016. SGMA Alternative Groundwater Sustainability Plan Bridge Document for the Mission Creek Subbasin. Prepared by MWH/Stantec.
CVWD, Coachella Water Authority (CWA), DWA, and Indio Water Authority (IWA) (Indio Subbasin GSAs). 2019. Indio Subbasin Annual Report for Water Year 2017-2018, prepared by Stantec.
CVWD, CWA, DWA, and IWA (Indio Subbasin GSAs). 2021a. Indio Subbasin Annual Report for Water Year 2019-2020. February 2021. Prepared by Todd Groundwater and Woodard & Curran.
CVWD, CWA, DWA, and IWA (Indio Subbasin GSAs). 2021b. Indio Subbasin Water Management Plan Update, Sustainable Groundwater Management Act Alternative Plan, prepared by Todd Groundwater and Woodard and Curran, December 2021.
CVWD, CWA, DWA, IWA, MSWD, and MDMWC. 2021c. 2020 Coachella Valley Regional Urban Water Management Plan. Prepared by Water Systems Consulting.
Coachella Valley SNMP Agencies. 2021. Workplan to Develop the Coachella Valley Salt and Nutrient Management Plan. April.
East Valley Reclamation Authority (EVRA). 2020. Evaluation of Indirect Potable Reuse at the Valley Sanitary District Water Reclamation Facility. November 2020. Prepared by Geoscience Support Services, Inc.
Fogg, G.E., G.T. O’Neill, E.M. LaBolle, and D.J. Ringel, 2000. Groundwater Flow Model of Coachella Valley, California: An Overview, November 2000.
Metropolitan Water District (MWD). 2020. Summary of Lake Perris Seepage Recovery Project Sharing Agreement Terms, DRAFT – As of November 26, 2019.
MWH. 2011. Groundwater Model Simulations for Coachella Valley Water Management Plan Update, for Draft Subsequent Program Environmental Impact Report, July 2011.
MWH. 2013. Mission Creek/Garnet Hill Subbasins Water Management Plan, Final Report, January 2013.
Sites Project Authority. 2019. 2019 Reservoir Project Agreement, As of April 1, 2019.
Sites Project Authority. 2020. First Amendment to 2019 Reservoir Project Agreement, As of January 1, 2020.
U.S. Bureau of Reclamation (USBR). 1931. 1931 Boulder Canyon Project Agreement. Available:
https://www.usbr.gov/lc/region/g1000/pdfiles/ca7pty.pdf U.S. Census Bureau. 2020. 2020 Demographic and Housing Estimates. Available at:
https://data.census.gov/cedsci/table?q=United%20States
U.S. Geological Survey (USGS). 2020. Detection and measurement of land subsidence and uplift using Global Positioning System surveys and interferometric synthetic aperture radar, Coachella Valley, California, 2010–17. U.S. Geological Survey Scientific Investigations Report 2020–5093. Authors: Sneed, M., and Brandt, J.T. Available: https://doi.org/10.3133/sir20205093 .
USGS. 1980. Potential for Using the Upper Coachella Valley Ground-Water Basin, California, for Storage of Artificially Recharged Water, Open‐File Report 80‐599.
Indio Subbasin Annual Report
for Water Year 2020-2021 TODD / W&C
APPENDIX A
Representative Groundwater Elevation Hydrographs
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(!(
!(
!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
Riverside
San Diego
Litt
l
e
S
a
n
B
e
r
n
a
r
d
i
n
o
M
o
u
n
t
a
i
n
s
Indio
H
i
l
l
s
S
a
n
J
a
c
i
n
t
o
M
o
u
n
t
a
i
n
s
Santa
R
o
s
a
M
o
u
n
t
a
i
n
s
MeccaHills
RiversideSan Diego RiversideImperial
SaltonSea
Im
p
e
r
i
a
l
Sa
n
D
i
e
g
o
KW_055
KW_012
KW_010
KW_007
KW_015
KW_013KW_014
KW_017
KW_019
KW_018
KW_020KW_021 KW_027
KW_028
KW_023
KW_029
KW_032 KW_034
KW_033
KW_040
KW_038
KW_046
KW_048
KW_003
KW_005
KW_006
KW_009
KW_025
KW_004
KW_008
KW_011
KW_016
KW_024
KW_026
KW_031
KW_035KW_036 KW_037
KW_039
KW_042 KW_043
KW_044 KW_045
KW_047
KW_051
KW_053
KW_054
KW_056KW_057
KW_052
KW_022
KW_001
KW_030
KW_041
KW_050
KW_049
KW_002
!(Key Well (57)
California County
Coachella Valley Water District
Coachella Water Authority
Desert Water Agency
Indio Water Authority
Figure A-1Selected Key Wellsfor GroundwaterLevel Monitoring January 2022
(N
0 6
Scale in Miles
Note:
Minimum groundwater elevation occured in 1968.
Figure A-1
Groundwater Elevation
Hydrograph
KW_001 - 03S04E17K01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
610
710
620
630
640
650
660
670
680
690
700
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_001 - 03S04E17K01S
Groundwater Elevation (feet msl)
Minimum Threshold (feet msl)
Figure A-2
Groundwater Elevation
Hydrograph
KW_002 - 03S04E22A01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
580
680
590
600
610
620
630
640
650
660
670
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_002 - 03S04E22A01S
Figure A-3
Groundwater Elevation
Hydrograph
KW_003 - 03S04E34R01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
240
340
250
260
270
280
290
300
310
320
330
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
271 - 03S04E34R01S
Figure A-4
Groundwater Elevation
Hydrograph
KW_004 - 03S05E30G01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
380
480
390
400
410
420
430
440
450
460
470
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_004 - 03S05E30G01S
Figure A-5
Groundwater Elevation
Hydrograph
KW_005 - 04S04E13C01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
180
280
190
200
210
220
230
240
250
260
270
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_005 - 04S04E13C01S
Figure A-6
Groundwater Elevation
Hydrograph
KW_006 - 04S04E24D01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
160
260
170
180
190
200
210
220
230
240
250
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_006 - 04S04E24D01S
Figure A-7
Groundwater Elevation
Hydrograph
KW_007 - 04S05E09B01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
150
250
160
170
180
190
200
210
220
230
240
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_007 - 04S05E09B01S
Figure A-8
Groundwater Elevation
Hydrograph
KW_008 - 04S05E15R02S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
90 190
100
110
120
130
140
150
160
170
180
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_008 - 04S05E15R02S
Figure A-9
Groundwater Elevation
Hydrograph
KW_009 - 04S05E17Q02S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
130
230
140
150
160
170
180
190
200
210
220
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_009 - 04S05E17Q02S
Figure A-10
Groundwater Elevation
Hydrograph
KW_010 - 04S05E28F02S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
100
200
110
120
130
140
150
160
170
180
190
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_010 - 04S05E28F02S
Figure A-11
Groundwater Elevation
Hydrograph
KW_011 - 04S05E29F01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
130
230
140
150
160
170
180
190
200
210
220
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_011 - 04S05E29F01S
Figure A-12
Groundwater Elevation
Hydrograph
KW_012 - 04S05E35G03S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
50 150
60 70
80 90
100
110
120
130
140
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_012 - 04S05E35G03S
Figure A-13
Groundwater Elevation
Hydrograph
KW_013 - 04S06E18R01S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
30 130
40 50
60 70
80 90
100
110
120
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_013 - 04S06E18R01S
Figure A-14
Groundwater Elevation
Hydrograph
KW_014 - 04S06E20M02S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A
S
e
r
v
i
c
e
s
2 0
1 9
-
7 5
0 0
4 \
T
a
s
k
O
r
d
e
r
7 -
W
Y
2 0
2 0
-
2 0
2 1
A
n
n
u
a
l
R
e
p
o
r
t
\
G
R
A
P
H
I
C
S
\
2 0
2 0
-
2 0
2 1
\
A
p
p
e
n
d
i
x
_
K
e
y
W
e
l
l
_
H
y
d
r
o
g
r
a
p
h
s
.
g
p
j
10 110
20 30
40 50
60 70
80 90
100
Gr
o
u
n
d
w
a
t
e
r
E
l
e
v
a
t
i
o
n
(
f
e
e
t
m
s
l
)
1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Year
KW_014 - 04S06E20M02S
Figure A-15
Groundwater Elevation
Hydrograph
KW_015 - 04S06E32N02S
January 2022
Pa
t
h
:
T
:
\
P
r
o
j
e
c
t
s
\
C
o
a
c
h
e
l
l
a
O
n
-
C
a
l
l
S
G
M
A