HomeMy WebLinkAboutResolution 2024-062 Approving and Authorizing the Water Director to Sign a Joint Funding Agreement with the US Dept of the Interior US Geological Survey N MARAN A RESOLUTIONO. 2024-062
RELATING TO WATER; APPROVING AND AUTHORIZING THE WATER DIRECTOR
TO SIGN A JOINT FUNDING AGREEMENT WITH THE U.S. DEPARTMENT OF THE
INTERIOR U.S. GEOLOGICAL SURVEY FOR WATER RESOURCES INVESTIGATIONS
IN THE TUCSON ACTIVE MANAGEMENT AREA FROM JULY 1, 2024, THROUGH
JUNE 30, 2028
WHEREAS the U.S. Geological Service, the Town of Marana, and other
governmental entities have since 2003 been jointly funding a study of changes in aquifer
storage and land-surface elevation in the Tucson Active Management Area; and
WHEREAS data from the study is used to improve understanding of the regional
aquifer and groundwater flow models used for water resource planning in the Tucson
Active Management Area; and
WHEREAS land-surface elevation change monitoring provides the distribution
and magnitude of differential subsidence,which can in turn help to guide the design and
implementation of maintenance and monitoring schedules, the selection of monitoring
methods, and the design and construction of future infrastructure; and
WHEREAS the Mayor and Council find this resolution is in the best interests of
the Town and its citizens.
NOW, THEREFORE, BE IT RESOLVED BY THE MAYOR AND COUNCIL OF
THE TOWN OF MARANA, ARIZONA, AS FOLLOWS: the Joint funding Agreement
between the Town of Marana and the U.S. Department of the Interior U.S. Geological
Survey, substantially in the same form included in the agenda materials accompanying
this resolution,is hereby approved,the Water Director is hereby authorized and directed
to sign it for and on behalf of the Town of Marana, and the various Town officers and
staff are hereby directed and authorized to undertake all other and further tasks required
or beneficial to carry out the terms, obligations, and objectives of the agreement.
-1 -
Resolution No.2024-062
PASSED AND ADOPTED by the Mayor and Council of the Town of Marana,
Arizona, this 18th day of May, 2024.
Mayor Ed Honea
ATTEST: APPROVED AS TO FORM:
Zkl, c\lr
David L. Udall, Town Clerk Jane F 'rall, Town Attorney
ANNOMBIN
--ARA
NA AZ
ESTABLISHED 1977
-2-
Resolution No.2024-062
t "T'
P United States Department of the Interior
,_ ‘ U.S.GEOLOGICAL SURVEY
"` Arizona Water Science Center
44ACN 3 `&ag 520 North Park
Tucson,AZ 85719
June 3,2024
Ms.Asia Philbin
Water Resources Coordinator
Town of Marana
11555 W.Civic Center Drive
Marana,AZ 85653
Dear Ms.Philbin:
Enclosed is our standard joint-funding agreement 24ZFJFA0900 between the U.S.Geological Survey Arizona Water
Science Center and Town of Marana for negotiated deliverables(see attached),during the period July 1,2024 through
June 30,2028 in the amount of$18,800 from your agency.U.S.Geological Survey contributions for this agreement
are$13,600 for a combined total of$32,400.Please sign and return one fully-executed original to Rudolph(Rudy)
Richard at rrichard@usgs.gov or mail to the address above.
Federal law requires that we have a signed agreement before we start or continue work.Please return the signed
agreement by June 17,2024.If,for any reason,the agreement cannot be signed and returned by the date shown
above,please contact Jamie Macy at(928)556-7276 or email jpmacy@usgs.gov to make alternative arrangements.
This is a fixed cost agreement to be billed quarterly via Down Payment Request(automated Form DI-1040).Please
allow 30-days from the end of the billing period for issuance of the bill.If you experience any problems with your
invoice(s),please contact Rudolph(Rudy)Richard at phone number(520)670-3302 or rrichard@usgs.gov.
The results of all work performed under this agreement will be available for publication by the U.S.Geological
Survey.We look forward to continuing this and future cooperative efforts in these mutually beneficial water
resources studies.
Sincerely,
DAMES Digitally signed by
DAMES LEENHOUTS
LEENHOUTS Date:2024.06.04
09:19:54-07'00'
James M Leenhouts
Director of Arizona Water Science Center
Enclosure
24ZFJFA0900
Form 9-1366 U.S. Department of the Interior Customer#:6000000832
(May 2018) U.S.Geological Survey Agreement#:24ZFJFA0900
Joint Funding Agreement Project#:
FOR TIN#:86-3301775
Water Resource Investigations
Fixed Cost Agreement YES[X] NO[ ]
THIS AGREEMENT is entered into as of the July 1,2024, by the U.S. GEOLOGICAL SURVEY,Arizona Water
Science Center, UNITED STATES DEPARTMENT OF THE INTERIOR, party of the first part,and the Town of
Marana party of the second part.
1.The parties hereto agree that subject to the availability of appropriations and in accordance with their respective
authorities there shall be maintained in cooperation for negotiated deliverables(see attached), herein called the
program.The USGS legal authority is 43 USC 36C;43 USC 50, and 43 USC 50b.
2.The following amounts shall be contributed to cover all of the cost of the necessary field and analytical work
directly related to this program.2(b)include In-Kind-Services in the amount of$0.00
(a) $13,600 by the party of the first part during the period
July 1,2024 to June 30, 2028
(b) $18,800 by the party of the second part during the period
July 1, 2024 to June 30,2028
(c) Contributions are provided by the party of the first part through other USGS regional or national programs,
in the amount of: $0
Description of the USGS regional/national program:
(d) Additional or reduced amounts by each party during the above period or succeeding periods as may be
determined by mutual agreement and set forth in an exchange of letters between the parties.
(e) Theperformanceperiod maybe changed bymutual agreement and set forth in an exchange of letters
9 9 9
between the parties.
3. The costs of this program may be paid by either party in conformity with the laws and regulations respectively
governing each party.
4.The field and analytical work pertaining to this program shall be under the direction of or subject to periodic review
by an authorized representative of the party of the first part.
5. The areas to be included in the program shall be determined by mutual agreement between the parties hereto or
their authorized representatives.The methods employed in the field and office shall be those adopted by the party of
the first part to insure the required standards of accuracy subject to modification by mutual agreement.
6. During the course of this program, all field and analytical work of either party pertaining to this program shall be
open to the inspection of the other party, and if the work is not being carried on in a mutually satisfactory manner,
either party may terminate this agreement upon 60 days written notice to the other party.
7.The original records resulting from this program will be deposited in the office of origin of those records. Upon
request, copies of the original records will be provided to the office of the other party.
8.The maps, records or reports resulting from this program shall be made available to the public as promptly as
possible.The maps, records or reports normally will be published by the party of the first part. However,the party of
the second part reserves the right to publish the results of this program, and if already published by the party of the
first part shall, upon request, be furnished by the party of the first part,at cost, impressions suitable for purposes of
reproduction similar to that for which the original copy was prepared.The maps, records or reports published by
either party shall contain a statement of the cooperative relations between the parties. The Parties acknowledge that
scientific information and data developed as a result of the Scope of Work(SOW)are subject to applicable USGS
review, approval, and release requirements,which are available on the USGS Fundamental Science Practices
website(https://www.usgs.gov/office-of-science-quality-and-integrity/fundamental-science-practices).
Form 9-1366 U.S. Department of the Interior Customer#:6000000832
(May 2018) U.S.Geological Survey Agreement#:24ZFJFA0900
Joint Funding Agreement Project#:
FOR TIN#: 86-3301775
Water Resource Investigations
9. Billing for this agreement will be rendered quarterly. Invoices not paid within 60 days from the billing date will bear
Interest, Penalties, and Administrative cost at the annual rate pursuant the Debt Collection Act of 1982, (codified at
31 U.S.C. §3717)established by the U.S.Treasury.
USGS Technical Point of Contact Customer Technical Point of Contact
Name: Jamie Macy Name: Asia Philbin
Supervisory Hydrologist/Associate Water Resources Coordinator
Director for Studies Address: 11555 W. Civic Center Drive
Address: 2255 North Gemini Drive Marana,AZ 85653
Flagstaff,AZ 86001 Telephone: (520)382-1900
Telephone: (928)556-7276 Fax: (n/a)
Fax: (928)556-7112 Email: aphilbin@maranaaz.gov
Email: jpmacy@usgs.gov
USGS Billing Point of Contact Customer Billing Point of Contact
Name: Rudolph(Rudy)Richard Name: Asia Philbin
Administrative Officer Water Resources Coordinator
Address: 520 N. Park Ave Address: 11555 W. Civic Center Drive
Tucson,AZ 85719 Marana,AZ 85653
Telephone: (520)670-3302 Telephone: (520)382-1900
Fax: (n/a) Fax: (n/a)
Email: rrichard@usgs.gov Email: aphilbin@maranaaz.gov
U.S.Geological Survey
United States Town of Marana
Department of Interior
Signature Signatures
JAMES Digitaly signed by
JAMESILEENHOU S
LEENHOUTSoa:2024-07'00' n 4�A '
By o9:zo:za-moo Date: By C Date: sA!
Name:James M Leenhouts Name: .31 P4�v t. Deign/
Title: Director of Arizona Water Science Center Title: s"NTERIi.., WA*c. DrRe raft
Aquifer-Storage Change and Land-Surface Elevation Change Monitoring in
the Tucson Active Management Area, July 1, 2024, to June 30, 2028
Introduction
The U.S. Geological Survey(USGS),in cooperation with local state and city agencies,
have been monitoring aquifer-storage change within the Tucson Active Management Area, here
referred to as TAMA, since the 1990's. The main method utilized is the repeat microgravity for
storage change and Interferometric satellite aperture radar (InSAR)for land surface elevation
change. Over the decades, the spatial extent of the monitoring has grown and expanded to now
include over 140 active stations within TAMA. The most recent report was from the period of
2003-2016 (Carruth and others, 2018), but data collection has continued biannually with data
releases being produced for the public.
The continued artificial recharge in the area, in addition to ephemeral streamflow and
groundwater pumping, allows for continued interest in aquifer-storage monitoring of the area. In
2020, the project included the maintenance and installation of new sites to replace monument
sites that have been lost or destroyed over the years. While no new sites are proposed to be
installed or replaced, an updated GPS survey is needed to archive and document all current
measurement sites within the area. Since gravity change is highly spatially variable, an accurate
GPS location and elevation of the sites is vital for repeat measurements at the same location.
This project relies on the use of two ZLS Burris relative gravity meters and two Micro-g
LaCoste A-10 absolute gravimeters for gravity monitoring, and iGage iG9 Global Navigation
Satellite System (GNSS) receivers for GPS surveying. Relative gravity meters are used to
measure the relative difference in gravity between two stations, but this method alone generally
cannot detect the slow scale of storage change that occurs over a multi-month or year timeframe.
Relative gravimeters are best utilized when paired with an absolute gravity measurement that
acts as a datum in which all changes can then be referred to. The absolute gravity meters provide
a measurement of the acceleration due to gravity at any location at any time, so the timing of
relative measurements is then required to be made in conjunction with absolute measurements in
order to achieve the best precision and accuracy of the gravity field at that time (Kennedy and
others, 2020). The GNSS survey is used to provide highly precise location and elevation data.
Data from the GNSS survey will be used in the final processing of the absolute data to account
for changes in elevation that could have been caused by land subsidence.
The most recent data collection has included a full survey in odd years and a partial
survey every even year. The full survey utilized all 140 stations in the network to provide maps
of storage change over most of the basin and the partial survey only included 40-60 sites. The
purpose of interceding full and partial surveys allows for storage change maps over the area to be
created biannually, and in the years in between select focus areas are surveyed to gain an in-
depth view of areas that show changes to previous trends. In FY28 year, a web-based
visualization method, known as a geo-narrative, will be created and made available to the public.
The geo-narrative will allow for visualization and conceptualization of the aquifer storage
change from the collected data.
The USGS proposes to continue working with Arizona Department of Water Resources
(ADWR), Pima County Regional Flood Control District, City of Tucson-Tucson Water, and the
Town of Marana, to collect relative and absolute gravity data, along with using InSAR data
provided by ADWR. The gravity data in conjunction with updated measuring station GPS data
will provide estimates of aquifer storage change through June 30th, 2028.
Problem
The volume of water artificially recharged or pumped from an aquifer is easily measured.
Estimations based on indirect methods must be used for other groundwater-budget components,
including withdrawals by small capacity (<35 gallon per minute) wells, evapotranspiration,
groundwater underflow from adjacent basins, incidental recharge from effluent recharge and
other sources, and natural recharge from many sources including mountain fronts and ephemeral
streams. This estimation of several groundwater-budget components results in large uncertainty
in the groundwater budget. The greatest uncertainty can be attributed to a lack of information
about natural recharge and groundwater-storage change. Estimates of the natural recharge rates
are highly uncertain and depend on accurate measurements of annual precipitation and
streamflow, which have high interannual variation (Pool, 2005). Estimates of groundwater
storage change are also highly uncertain when computed as residuals in the water budget
equations because the storage term includes the cumulative uncertainty of all other components.
Water levels in wells have been monitored to estimate aquifer-storage changes. However,
use of water-level variations entails significant assumptions about the hydraulic propel ties of the
aquifer system. One difficulty is the heterogeneity of hydro logic properties of the aquifer; the
alluvial sediments of the aquifer vary in lithology and texture, both laterally and with depth.
Thus, hydraulic properties estimated from water levels in individual wells may not adequately
represent aquifer characteristics at distances away from the well. A second difficulty is monitor-
well design; particularly when water levels are measured in deep wells that tap multiple aquifers,
most of which are confined and have accordingly low storage properties. Water levels in these
deep wells open to multiple aquifers represent a composite of water levels from several aquifer
units. When these composite water levels are used to estimate storage changes, the hydrologic
properties used in the calculation typically do not reflect the range of aquifer materials over
which the well is screened. Water-level responses also depend on the geometry and lithology of
the hydrogeologic units that constitute the aquifer system that wells sample. This information
often is incomplete, or uncertain. Because of these complexities and requisite assumptions, use
of water-level variations as the only indicators of storage change can be uncertain and cannot be
reliably extrapolated beyond the well location.
Aquifer-storage can be monitored by measuring changes in gravity alone. As water is
added or removed from the aquifer, there is a change in mass and a corresponding measurable
change in gravity. The repeat microgravity method is an established method for monitoring
aquifer-storage changes in alluvial basins (Kennedy and others, 2021). Monitoring of gravity and
groundwater levels in the Tucson Basin has shown that large changes in groundwater storage, as
much as several feet of water, have occurred that were not reflected in comparable water-level
changes (Carruth and others, 2018).
The City of Tucson's water utility, Tucson Water, manages many artificial recharge
projects in the project area. Two of importance are the Central Avra Valley Storage and Recovery
Project (CAVSARP)and Southern Avra Valley Storage and Recovery Project (SAVSARP).
These two facilities, located in the eastern part of Tucson, have seen reduced volumes of
recharge into the subsurface since 2021. The response to the variable recharge rates of these
areas will be of particular interest to the city of Tucson as the observed aquifer storage is thus
affected.
Permanent land subsidence can occur in alluvial basins when water is removed from
aquifer systems (Galloway and others, 1999).Aquifer systems in unconsolidated rocks such as
those in the Tucson AMA are supported by the granular skeleton and the pore-fluid pressure.
When groundwater is withdrawn and the pore-fluid pressure is reduced, the granular skeleton is
compressed, causing some lowering of the land surface. Both the aquifers (sand and gravel) and
aquitards (clay and silt) of aquifer systems are deformed as a result of changes to the pore-fluid
pressure and skeleton, but to different degrees. Continued monitoring of areas having the greatest
potential for subsidence will provide information that resource managers can use in the
development and implementation of mitigation efforts.
Objectives
The objective of this project is to monitor the aquifer-storage change and land-surface
elevation change in the Tucson AMA using microgravity monitoring techniques. In full survey
years, gravity measurements will be conducted at all established gravity stations (approximately
140 stations), see figure 1. Every other year, in the off years, data collection will consist of a
subset of locations where gravity will be measured in order to access areas of interest. In Fiscal
Year 2026, a GPS survey will be conducted at all sites to update the total list and site descriptions
of every site.
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Figure 1: Map of current relative and absolute gravity site locations across the Tucson Active
Management Area(TAMA). The distribution of sites allows for coverage of almost the entire
active management area.
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Figure 2: Storage change map from 2021-2023 of the Tucson AMA area. Storage losses
continued in the south and central areas of the study while storage increases were seen to the
northwest and in localized areas in central Tucson.
Approach
Gravity data will be collected using both absolute and relative gravity meters over the
period of 2 to 6 weeks depending on yearly scope of each survey. Data collection can occur
anytime with November-January of each fiscal year, as long as all data is collected within a fairly
continuous timeframe. This reduces the likelihood of large pumping or natural recharge events to
alter the accuracy of storage change in the subsurface. In years of a full survey, all 140 site
locations will be measured. In years of partial surveys, roughly 40-60 sites will be measured in
specific areas of interest will be decided with input from all cooperators to focus on unique
water-level trends of the year. Since all station locations are previously established, no additional
locations are required to be constructed.
Land-surface elevation change is monitored across the Tucson AMA by measuring
changes in land surface elevation over time (approximately annually) with Interferometric
Synthetic Aperture Radar (InSAR). These data come from the Arizona Department of Water
Resources (ADWR), which has an InSAR program in the Tucson AMA. InSAR is a technique
that utilizes interferometric processing to compare the amplitude and phase signals received
during one pass of the satellite-based SAR platform over the AMA with the amplitude and phase
signals received during a second pass of the platform over the same area but at a different time.
Relevance and Benefits
The repeat microgravity method is an efficient, noninvasive technique to determine
changes in groundwater from the surface without needing to drill into the ground (Pool, 2008).
The method allows for quick data collection over a large geographic area while providing a
quantitative value of storage change. This will benefit ADWR's goal of monitoring the
groundwater basins and understanding the hydrologic system within the Tucson AMA.ADWR's
additional goal for the Tucson AMA is to achieve safe yield in the basin which requires the
maintaining of a long-term balance between the amount of groundwater withdrawn in an Active
Management Area and the annual amount of natural and artificial recharge. This also will benefit
Pima County, the Town of Marana, and Tucson Water by better understanding the water budget
and groundwater storage of the basin their water-users are reliant on. This work is consistent
with and supports the USGS water science strategy outlined in Evenson and others, (2013) by
advancing the hydrologic monitoring networks and techniques by enhancing the available
information including the aquifer storage.
Regional subsidence in response to groundwater pumping is unlikely to end in the near
future. It will continue until the aquifer system reaches pressure equilibrium. Observation of the
timing and magnitude of aquifer responses will further improve the understanding of land
subsidence and of how the aquifer systems function. Monitoring data also will contribute to a
better understanding of the responses of the aquifer systems to withdrawals and will provide
additional insight for future plans for well site selection, recharge efforts, and water-management
programs.
Data Management Plan
All gravity data will be collected by trained personnel using techniques consistent with
published methodologies for using microgravity to investigate and monitor aquifer-storage
change and land subsidence (Kennedy and others, 2021). Data will be archived in the Arizona
Water Science Center gravity data archive. All data will be published as one or more formal data
releases at the USGS Southwest Gravity Program ScienceBase website (USGS Southwest Gravity
Program-ScienceBase-Catalog).
Data collected during each year of a full survey will be published online within five
months of final data collection. All gravity data for the project will be processed, reviewed,
approved, and published following QA/QC protocols established by the USGS Southwest
Gravity Program (Kennedy and others, 2021). Gravity data will be processed by USGS
personnel in the office within 3 months of data collection. An experienced reviewer will review
and check the data for accuracy. Data releases will be peer-reviewed and include complete
metadata. Once published, data will be publicly accessible.
GPS data of station positions will be archived at the Arizona Water Science Center. Data
will be processed using the National Geodetic Survey Online Positioning User Service or Project
Networks and (or) OPUS projects service.
Deliverables and Timeline
Data releases will be made available after each full survey year. Cooperator meetings will
be held in the summer to provide updates on the produced storage change maps and allow for the
discussion of what areas to focus on during the partial survey. After partial surveys, data releases
will not be made but cooperator meetings can occur, if requested.
In the fourth year, a publicly available web-based product, called a geo-narrative, will be
created. The geo-narrative will allow for a unique way to visualize and conceptualize the data
collected and be suitable for a general audience to better understand the changes to the local
groundwater supply.
The table below summarized the cost breakdown per year and per agency for the entire
project. Fiscal years 2025 and 2027 will be full surveys with the cost adjusted to the additional
field work. Fiscal year 2026 is a partial survey but also includes the additional GPS survey to
inventory all active sites. Finally, fiscal year 2028 will include a partial survey and the associated
geo-narrative of all data.
Fiscal FY2025 FY2026 FY2027 FY2028
Year
Cooperators USGS Cooperators USGS Cooperators USGS Cooperators USGS
ADWR $24,800 $17,800 $25,500 $ 18,300 $26,200 $ 18,800 $ 20,200 $ 14,500
Pima $ 17,900 $ 12,800 $ 18,400 $ 13,200 $ 18,900 $ 13,600 $ 14,600 $ 10,500
County
City of $4,800 $ 3,500 $ 5,000 $ 3,600 $ 5,100 $ 3,700 $ 3,900 $ 2,800
Marana
Tucson $6,200 $4,400 $ 6,400 $ 4,600 $ 6,600 $ 4,700 $ 5,100 $ 3,600
Water
Totals $53,700 $38,500 $55,300 $39,700 $56,800 $40,800 $43,800 $ 31,400
Table 1: Project budget by state fiscal year(FY). FY 2025 is July 1, 2024 to June 30, 2025, but
work, and therefore billing, would not begin until October 2024.
References
ADWR Geophysics& Surveying Unit, undated,
https://new.azwater.gov/sites/default/files/GSU FactSheet 006.pdf
Carruth, R.L., Kahler, L.M., and Conway, B.D., 2018, Groundwater-storage change and land-
surface elevation change in Tucson Basin and Avra Valley, south-central Arizona-2003-
2016: U.S. Geological Survey Scientific Investigations Report 2018-5154, 34 p.,
https://doi.org/10.3133/sir20185154.
Conway, B., 2014, Land Subsidence Monitoring Report No. 2,Arizona Department of Water
Resources, https://www.azwater.gov/sites/default/files/2022-
08/ADWRLandSubsidenceMonitoringReport Number2_Final.pdf
Evenson, E.J., Orndorff, R.C., Blome, C.D., Bohlke, J.K., Hershberger, P.K., Langenheim, V.E.,
McCabe, G.J., Morlock, S.E., Reeves, H.W., Verdin, J.P., Weyers, H.S., and Wood, T.M.,
2013, U.S. Geological Survey water science strategy—Observing, understanding,
predicting, and delivering water science to the Nation: U.S. Geological Survey Circular
1383—G, 49 p.
Galloway, D.L., Jones, D.R., and Ingebritsen, S.E., 1999, Land subsidence in the United States:
U.S. Geological Survey Circular 1182, 175 p.
Kennedy, J.R., Pool, D.R., and Carruth, R.L., 2021, Procedures for field data collection,
processing, quality assurance and quality control, and archiving of relative- and absolute
gravity surveys: U.S. Geological Survey Techniques and Methods, book 2, chap. D4, 50
p., https://doi.org/10.3133/tm2D4.
Landrum, M.T., 2021, Repeat microgravity data from Tucson Basin and Avra Valley, Arizona,
2021: U.S. Geological Survey data release, https://doi.org/10.5066/P952DOWL.
Pool, D. R., 2008, The utility of gravity and water-level monitoring at alluvial aquifer wells in
southern Arizona: GEOPHYSICS, 73(6), WA49-WA59.
https://doi.org/10.1190/1.2980395
U.S. Geological Survey, 2021, Southwest Gravity Program Absolute-Gravity Database (updated
2022-12-18): U.S. Geological Survey data release, https://doi.org/10.5066/P984HN6J