Active Management Area Population - Population Growth and Water Use

Arizona was the second fastest growing state from 2000 to 2006, with a 20.2% statewide population increase (4% annually). However, from 2006 to 2009 the statewide annual growth rate slowed to about 2% due to the national recession.  Population in the planning area increased by 25% between 2000 and 2006 and by 38% between 1990 and 2000.  Census data for 2000 show a population of approximately 4.1 million residents and projections by the Arizona Department of Commerce and Councils of Government suggest that the planning area population will more than double by 2030 to over 9.1 million.  Historic, current and projected AMA populations are shown in the cultural water demand tables for each AMA in Sections 8.1 - 8.5.

The Phoenix AMA is the most populous AMA with approximately 75% of the total planning area population in 2000.  The Tucson AMA has the second largest percentage of population in the planning area with 20% in 2000. The 2000 Census populations for each AMA and Indian reservations are shown in Table 8.0-4.

Almost all AMAs experienced growth rates in excess of the state average from 2000 to 2006. During this time-period Prescott AMA population increased by 32%, Phoenix AMA population increased by 22% and the Pinal AMA population grew by 61%.  The Tucson AMA population increased at a lower rate of 17% during this period.  In the Santa Cruz AMA, population increased by 34%, mostly in unincorporated areas where the combined population exceeded that of the City of Nogales for the first time in 2006.

Listed in Table 8.0-5 are communities in the planning area with 2000 Census populations greater than 1,000 persons and growth rates for two time-periods: 1990-2000 and 2000-2006.  As listed, there were a number of rapidly growing communities in the planning area. The community of Maricopa in the Pinal AMA grew 1,643% between 2000 and 2006. The community of Marana in the Tucson AMA grew 520% between the years 1990 and 2000 and an additional 125% from 2000 to 2006. Many other communities in the planning area grew by several hundred percent during one or both time periods. Gilbert, Surprise and Goodyear, all in the Phoenix AMA, grew by more than 200% between 1990 and 2000. The Town of Prescott Valley in the Prescott AMA grew by 164% in the same time-period.

Every developer proposing to build a new subdivision is required to demonstrate an AWS that will be physically, legally, and continuously available for the next 100 years before the developer can record plats or sell parcels.  The Arizona Department of Real Estate will not issue a Public Report, which allows the developer to sell lots, without a demonstration of an AWS.

In 1995, the Department adopted AWS Rules to implement the AWS statutes. An important component of the AWS Rules is the requirement to demonstrate that renewable water supplies will be used rather than mined groundwater. This requirement did not apply to the Prescott AMA until 1999 when the AMA was declared to no longer be in a safe-yield condition.

The Santa Cruz AMA was established July 1, 1994 near the end of the period when the AWS Rules were being drafted. Consequently, it was not possible to include rule provisions that applied to the management goal of the Santa Cruz AMA at that time since goal criteria had not been developed.  Although the general  provisions apply, the Department is still developing specific AWS Rules for the Santa Cruz AMA where relatively limited groundwater storage capacity directly influences the availability of water supplies and where the hydrologic situation may affect the course of population growth in this AMA.

Following adoption of the AWS Rules, rapid population growth in the Pinal AMA led to modification of the AMA’s AWS Rules in order to reduce the over allocation of unreplenished groundwater supplies.  This rule change, which took effect on October 1, 2007, substantially reduced the volume of groundwater that can be used without replenishment by new developments, from close to 100% under the old rules to as little as 10% under the new rules.

Under the AWS Rules, developers can prove a 100-year water supply by satisfying the requirements to obtain a Certificate of AWS or by a written commitment of service from a provider with a Designation of AWS. The AWS Rules list in detail what an applicant for a Certificate of AWS or a Designation of AWS must demonstrate. In addition to securing a water supply that is physically, legally, and continuously available for the next 100 years, to obtain a Certificate the developer must prove that the supply is of sufficient quality and is consistent with the AMA management goal and management plan.  Finally, the developer must demonstrate the financial capability to construct any necessary water storage, treatment, and delivery systems. Water providers seeking a Designation of AWS must demonstrate a 100-year water supply for their entire service area for both current and committed demand, as well as projected demand. A list of Designated water providers in the planning area can be found in Table 8.0-6.

Before the AWS program was created in 1980, the Adequate Water Supply program was effective statewide. This program was created in 1973 as a consumer protection program and is still in effect outside the AMAs.  If a developer can successfully demonstrate that water of sufficient quality will be physically, legally and continuously available for the next hundred years, the Department will issue a Water Adequacy Report with a determination that the water supply is adequate. If the Department determines that there is an inadequate water supply, the developer can still sell the lots in most areas but must disclose this fact to potential buyers.5 Because the Adequate Water Supply program was in effect in the planning area prior to 1980, some Water Adequacy Reports issued for older developments in the AMAs exist.

Prior to obtaining a Certificate of AWS, developers also have the option to obtain an Analysis of AWS (Analysis). An Analysis is generally used to prove that water will be physically available for master planned communities but may be used to demonstrate other criteria required for a Certificate of AWS.  An applicant for an Analysis must demonstrate that one or more of the requirements for an AWS are met, but need not demonstrate that all have been met. If an Analysis is issued for groundwater, it reserves a specific volume of water for 10 years for the specific property that is the subject of the Analysis.  However, an Analysis cannot be used to obtain a Public Report and must be followed by a complete demonstration of all the criteria to obtain a Certificate of AWS.

A summary of the planning area’s AWS determinations through 2008, including AWS Certificates (27’s), Analysis of AWS (28’s), Water Adequacy Reports (53’s) and AWS Designations (26’s) can be found in Table 8.0-7.  Detailed information on individual determinations are found in the AMA Assured Water Supply sections, 8.1.9 - 8.5.9. Up to date information on certificate and designation applications and issuances are found on the Department’s website.

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