The
City of Mesa Drought Plan was approved by Council in October 2003.
 General Principles
Drought is a natural climatic condition that has occurred many times in the
past, and that will occur again in the Sonoran Desert. For this reason,
preparation for drought is an ongoing process. A drought occurs when there are
several consecutive years of below normal/average precipitation on the watershed
that result in reduced streamflows and reservoir levels. Mesa has planned for
these drier years by securing and managing a variety of water sources, and
encouraging voluntary water conservation.
The purpose of this Drought Management Plan is to endorse a management
framework for:
- dealing with drought conditions when they occur
- preventing the need to implement drastic demand reduction measures, such
as rationing of water supplies
- planning for future drought conditions before they occur
Background
Mesa is fortunate to have multiple
water
sources. The majority of Mesa's water supply is surface water from the Salt
and Verde Rivers, delivered by SRP. Mesa also receives a large amount of water from the Colorado River through the
Central Arizona Project (CAP). When additional water is needed, groundwater and surface water that has been
stored underground are pumped from the many wells located throughout the city.
Mesa captures wastewater, and treats it to a very high-standard drinking water
quality, then allows it to percolate back into the ground where it is stored for
future use. Mesa also stores surplus surface water underground. These sources
combined, replenish our groundwater and allow Mesa to accumulate long-term
storage credits.
Mesa has amassed 367,000 acre-feet of long-term storage credits, and continues
to build that credit for the purpose of meeting water demand during a drought,
and to demonstrate that the City has a one hundred-year assured water supply.
From the operations perspective, ultimate drought preparation comes in the
form of having adequate well and wellhead treatment capacity to meet water
demand when surface water supplies are short. The
Water
Division has worked for years to successfully maintain the well
capacity needed to meet customer demand during times of drought. Since 1982,
Mesa has been promoting and encouraging voluntary water conservation, regardless
of the amount of water available. However, if drought conditions prevail for an
extended period of time, it may be necessary to initiate water-use restrictions.
Another benefit to conservation during times of drought is one associated
with cost. Droughts potentially cause an increase in the cost to Mesa's Utility
in meeting its customers' demands. For example, when SRP water supplies are
short, they may be supplemented with more expensive CAP water. Demand should be
managed during these times, first to prevent the need to ration water supplies,
but also to mitigate the impact of increased costs for water supplies.
Drought Plan
The City of Mesa Drought Management Plan complements ongoing water resource
and water operations planning efforts, and is designed to be a flexible tool to
plan for, mitigate, and respond to drought conditions. At the heart of the
Drought Management Plan is the Drought Management Team (Team).
Members of the Team shall include at a minimum:
- The Manager of the Resources Division, Utilities Department
- The Utilities Conservation Supervisor
- The Water Resources Coordinator
- A member of the Budget and Research staff
- The Utilities Financial Analyst
- The Water Production Superintendent
- The Utilities Department Public Information Officer
- The Water Quality Supervisor
- The Utilities Attorney
The Water Resources Coordinator will monitor drought signals on an ongoing
basis and send out information biannually regarding the condition of relevant
watersheds to members of the Team. When a climatological drought occurs or is
imminent, upon recommendation of the Water Resources Coordinator and the Manager
of the Utilities Department, the City Manager will activate the Team.
It will be the responsibility of the Team to evaluate the severity of the
drought, and develop an action plan based on current and forecasted water supply
and demand, and economic impact to the City.
Drought impacts will vary with both the severity and length of the drought. Factors typically used to evaluate the impact of a drought include the
availability of current and projected water supplies, current and projected
customer demands, the availability of current and future water supply
infrastructure, the condition of surface water reservoirs, and projections from
climatologists regarding the magnitude and duration of the drought. The Team
shall use these factors to evaluate the best-case, worst-case, and most likely
scenarios regarding the severity and length of the drought.
After undertaking such analysis, the Team shall report back to the City
Council. The Team shall present the following:
- An analysis of the probable impact to City of Mesa water supplies
- An analysis of the probable financial impacts of the drought
- An analysis of the potential need for and availability of alternative
water supplies
- A recommended change of use of water supply sources, if necessary
- A recommendation regarding demand management
- A recommended change in water and/or wastewater rates, if necessary
- A legal analysis of the recommended actions
The Team shall continue to monitor the situation, and meet at least quarterly
throughout the duration of the drought, updating strategies as necessary. After
the Water Resources Coordinator determines that the drought has passed, the Team
shall prepare a report detailing the successes and failures of the strategies
used during the drought, and provide a recommendation regarding on-going
planning and preparation for the next drought.
Stage One
Upon the recommendation of the Manager of the Utilities Department, the City
Council may declare Stage One when a surface water shortage that will affect the
City of Mesa is predicted or occurs. Mesa's Water Resources staff monitors the
precipitation and water storage levels of the Colorado, Salt, and Verde River
watersheds. A reduction in surface water supplies can be predicted several
months prior to the actual announcement of a reduction in surface water
deliveries. At this stage of the drought, Mesa is capable of meeting demand
through remaining surface and groundwater supplies.
The following measures may be implemented in response to a Stage One
event:
- Increased monitoring by Water Resources of SRP and CAP surface water
supply availability
- Reporting by Water Resources to the Manager of the Utilities Department,
the City Manager, and the City Council as water supply conditions change
- Increased community education on water conservation
- Encouragement of HOA's, apartment communities, owners and managers of
large turf facilities to not overseed in the fall
- Reduction of water use in City facilities, including but not limited to
reduction of hours of operation of water features, and limits on
overseeding
Stage Two
Upon the recommendation of the Manager of the Utilities Department, the City
Council may declare Stage Two when SRP combined deliveries of Stored and
Developed water are cut to less than 1.5 acre-feet per acre and/or CAP
Subcontract and Indian Lease water availability is cut to an amount that is
equal to or less than eighty percent of the amount of Subcontract and Indian
Lease water used in the most-recent non-drought year. At this stage, Mesa is
capable of meeting demand through its remaining surface water supplies, banked
water, and wells. Stage Two will implement voluntary water conservation to
reduce the impact of the potential use of more expensive water supplies.
In addition to the measures implemented during a Stage One event, one or more
of the following demand management measures may be requested of all water
customers:
- Reduce water consumption 5-10% by eliminating waste, repairing leaks, and
eliminating unnecessary outdoor water use
- Run lawn sprinklers only between the hours of 7 p.m. to 7 a.m.
- Turn off decorative water features and outdoor misting systems
- Forego overseeding in the fall
- Increase cooling tower cycles to three cycles of concentration or higher
- Reduce frequency of outdoor watering
Additionally, the City of Mesa may:
- Intensify its leak detection and repair program, and meter replacement
program
- Develop and implement a public awareness program to alert residents to
drought conditions, its potential impact to Mesa's water supplies, and that
mandatory measures may be imposed if the drought conditions continue
Stage Three
Upon the recommendation of the Manager of the Utilities Department, the City
Council may declare Stage Three when SRP combined deliveries of Stored and
Developed water are cut to less than one acre-foot per acre and/or CAP
Subcontract and Indian Lease water availability is cut to an amount that is
equal to or less than sixty percent of the amount of Subcontract and Indian
Lease water used by Mesa in the most-recent non-drought year. At this stage,
Mesa is capable of meeting demand through its remaining surface water supplies,
banked water, and wells. Stage Three will require implementing mandatory demand
management measures to reduce the impact of using increasingly expensive water
supplies.
One or more of the following measures may be implemented in response to a
Stage Three event:
- Voluntary water management measures identified in Stage One and Stage Two
may become mandatory
- Identify major water users, and require them to develop a water
conservation plan
- Limit lawn watering according to published schedule
Additionally, the City of Mesa may:
- Examine commercial and residential development standards, and recommend
changes that will result in more efficient use of water
- Remove turf from public right-of-ways, and convert all parks to meet the
new water efficient landscape design standards
- Intensify community education effort
- Increase staff resources to implement drought response measures
- Increase water rates
- Implement civil penalties for wasting water
Stage Four
Upon the recommendation of the Manager of the Utilities Department, the City
Council may declare Stage Four when water deliveries are insufficient to meet
projected water demand. Mandatory customer water use restrictions are
implemented in Stage Four to ensure that basic water needs for Mesa residents
and businesses will be met. In addition to the measures implemented during
Stages One through Three, one or more of the following measures may be
implemented in response to a Stage Four event:
- Mandatory water use restrictions
- Limitation on new water connections
- Drought surcharges
For more information about the City's Drought Plan, contact Kathryn
Sorensen, Water Resources Coordinator.
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