General Information

Questions & Answers

Arizona Navigable Stream Adjudication Commission

(Updated October 22, 2001)

ANSAC does not deal with water use, water diversion, or other water rights issues.  ANSAC deals only with watercourse navigability as of statehood February 14, 1912 .  There are approximately 100,000 Arizona property titles that will remain clouded until the navigability or non-navigability of each of Arizona ís 39,039 watercourses has been determined.  The Commission is charged with making these determinations.  

Q.            What does the Arizona Navigable Stream Adjudication Commission (ANSAC) do?

A.           ANSAC engages in research, collection of evidence, and formal hearings that result in final determinations, with a right of appeal,  regarding the navigability or non-navigability of each of Arizona ís 39,039 watercourses as of statehood, February 14, 1912 .  


Q.            Why does the navigability or non-navigability of Arizona watercourses at statehood matter?

A.            Because all Arizona property across, bordering, or onto which a watercourse travels may be subject to either private ownership or state ownership, depending on navigability as of statehood.  Until the matter has been resolved, as many as 100,000 Arizona property titles will remain clouded.  


Q.           What is the most common question or concern received by ANSAC staff?

A.           By far the most common question received in the ANSAC offices comes from Arizona citizens who express their concern that the state is trying to confiscate their private property, and that they may have to sue the state to acquire clear title.  The second most frequent question is from Arizona citizens concerned the state is going to give all of the rivers to corporations and private citizens. 


Q.            Have Arizona watercourses historically typically been used for navigation?

A.            No.  Water use for irrigation and not navigation, has been far more significant to arid or desert regions such as Arizona .   Arizona includes parts of at least three of the four North American deserts.  The four North American Deserts are the Great Basin , the Chihuahuan, the Mojave, and the Sonoran.  


Q.            How many watercourses are there in Arizona ?

A.            Approximately 39,039 rivers, creeks, streams, washes, lakes, arroyos, channels, etc.  Stock ponds, canals, and irrigation ditches or channels are not included in ANSAC's studies. 


Q.            Does ANSAC determine who receives water; how much, and when?

A.            No.  The work of ANSAC has nothing to do with water use.  There are other agencies and laws that govern water use.


Q.            Is  the Colorado River included in ANSAC's work?

A.            No.  The Colorado River is controlled by the Federal Government.


Q.            What is the process for deciding whether a watercourse is navigable or not?

A.            ANSAC has divided its work between major watercourse studies and small or minor watercourse studies.  Major watercourses are studied individually, and hearings are held in each county into which each major watercourse travels.  Small or minor watercourses are studied county-wide, for each respective county.  At least one hearing is held in each county regarding all of the small or minor watercourses in that county.   Following hearings, review of evidence and post trial briefs the Commission will make a determination regarding navigability or non-navigability which can be appealed to superior court.


Q.            What happens if a major watercourse or a small or minor watercourse borders two counties?

A.            Evidence is gathered, studies are done, and a separate hearing is held in each county.


Q.            Can a portion or portions of a major watercourse be navigable and other portions of the same watercourse be non-navigable.

 A.            Yes.  Portions or reaches of a watercourse, or an entire watercourse, can be either navigable or non-navigable.


Q.            How will I know if ANSAC is going to hold hearings in my county?

A.            ANSAC will place an advertisement of Notice of Intent to Study once a week for three consecutive  weeks in a local newspaper in the county where each respective watercourse is being studied.  Such advertisements ordinarily appear about 60 days before a hearing is held.  The purpose of Intent to Study ads is to obtain historical and other information or evidence from interested parties who live in the area where the watercourse is being studied.  The Commission will also place an advertisement of Notice of Hearing in a statewide newspaper, and in a local county newspaper, at least thirty-days prior to each hearing.   In addition, the Commission publishes agendas regarding its hearings and other meetings, and these agendas are posted on this web site.


Q.            Are advertisements regarding small or minor watercourse studies and hearings the same as advertising relating to major watercourses?

A.            Yes.  The primary difference is that small or minor watercourse advertisements deal with numerous watercourses, whereas each major watercourse advertisement deals with a single watercourse.


Q.            Do ANSAC's processes regarding small or minor watercourses, in a particular county, allow for some watercourses to be determined navigable and for others to be determined non-navigable?

A.            Yes.  Small or minor watercourses in a particular county are studied in a three-level process developed and refined by engineers during the past three years or so.  If a watercourse survives all three levels, then it will be studied individually, in detail, in a manner similar to that undertaken for major watercourses.


Q.            How many Arizona watercourses are named, and how many are unnamed, and if a small or minor watercourse is unnamed, how do you know what watercourse you are studying?

A.            Of the approximately 39,039 Arizona watercourses, approximately 2,241 are named watercourses, and approximately 36,798 are unnamed watercourses.  All major watercourses are named.  All watercourses, named and unnamed, are identified by U.S.G.S. Hydrologic Unit Code Segment Numbers; and by Township, Range, and Section.  Segment numbers and township, range, and section information regarding watercourses, together with global position satellites, can be used to pinpoint specific locations along any watercourse.


Q.            Who presents information or evidence at a hearing?

A.            Individual citizens of Arizona , representatives of groups or organizations having an interest in the watercourse or watercourses being studied, state officials, and professionals including hydrologists, geomorphologists, geologists, other engineers, historians, etc.


Q.            What factors or information are considered in the studies of watercourses to determine navigability or non-navigability as of statehood?

A.            History, geology, hydrology, hydraulics, geomorphology, archeology, commerce, boating, fish, dams, and virtually any other information that will shed light on the condition of the watercourse concerning navigability as of Arizona statehood, February 14, 1912.


Q.            What happens following an ANSAC hearing?

A.            After all evidence and testimony have been received the Commission will ask that post-hearing memoranda be filed with the Commission by a specified date.  Once the post-hearing memoranda have been studied by the Commission, the Commission will make a determination of navigability or non-navigability and findings of fact, conclusions of law, and determination will be published, following which there will be a time for appeal.


Q.            Is there any benefit to the work of ANSAC beyond determining the navigability of watercourses as of statehood, and clearing approximately 100,000 clouded Arizona property titles?

A.            Yes.  All of the information gathered by ANSAC will be permanently archived by the state and will be available for future research.  For example, for the first time ever, all Arizona watercourses are being mapped as part of the engineering study process relating to the work of ANSAC.


Q.            What will happen to ANSAC once the work is completed?

A.            ANSAC is unique as a state agency in that it is one of the very few agencies, if not the only agency, planning to complete its work and go out of business.  Once ANSAC's work has been completed, ANSAC will close down and all of the evidence and other data gathered, including extensive database information, will be archived by the state, and will continue to be available to the public.