UPPER VERDE RIVER Files

Geologic Framework of Aquifer Units and Ground-Water Flowpaths, Verde River Headwaters, North-Central Arizona

Abstract: This study combines the results of geophysical, geologic, and geochemical investigations to provide a hydrogeologic framework of major aquifer units, identify ground-water flowpaths, and determine source(s) of base flow to the upper Verde River. This introductory chapter provides an overview of previous studies, predevelopment conditions, present surface-water and ground-water conditions, and a conceptual water budget of the hydrologic system. In subsequent chapters, this conceptual model will be evaluated and refined with respect to the results of each successive investigation. First, a compilation of mapping and field verification of the surficial geology, reinterpretation of driller’s logs, and contour mapping of alluvial thicknesses and buried volcanic rocks provide new three-dimensional geologic information. Second, a suite of geophysical techniques—including aeromagnetic and gravity surveys and inverse modeling approaches—was used to interpret the deeper subsurface geology. Third, geologic, geo- physical, and hydrological data were integrated to define basin boundaries, describe aquifer units in the basin-fill aquifers of Big and Little Chino valleys and the regional carbonate aquifer north of the upper Verde River, and develop a hydrogeologic framework. Water-level gradients were used to infer outlet flowpaths from the basin-fill aquifers through the carbonate aquifer toward the upper Verde River. Fourth, geochemical investigations employing analyses of dissolved major and trace elements and isotopes of δD, δ18O, 3H, 13C, and 14C were used to characterize major aquifers, identify recharge areas, and determine evolution of water chemistry along ground-water flowpaths. Fifth, results of a tracer-dilution study and synoptic sampling identify locations of major spring inflows discharging to the upper Verde River, measure base-flow contributions, which were used to calculate the relative contributions from each aquifer to upper Verde River springs using inverse geo- chemical modeling. In the final chapter, synthesis of multiple lines of evidence improve understanding of the relationships between the three aquifers, regional ground-water flowpaths, and the proportion of flow from each aquifer to the upper Verde River. Collectively, data from many varied and indepen-dent sources improves confidence in the conceptual model of the hydrogeologic system.

This file consists of 7 chapters and 246 pages totaling 135 mb. It can be downloaded here. 

Going with the Flow 2013

View Document.

Going with the Flow Update Final_04-23-2018

View Document.

Hearing Things: The Rumble of the 900-lb SRP Gorilla in Administrative Hearings on Prescott's Pipeline

Entertaining analysis of the 2009 hearings on Prescott's application for a permit to pump the Big Chino. View Document.

How Pumping the Big Chino Affects the Flow in the Verde River

Ground water pumping in the Big Chino Valley reduces the base flow of the Verde River by intercepting and consuming ground water that would otherwise discharge from springs in the Verde River Canyon. Historical and current data support this idea. Several ADWR, USGS, USBR and private consultants' investigations have all pointed to the hydrologic connection between the ground water flowing through the Big Chino Valley Aquifer and the base flow of the Verde River. Increased pumping in the Big Chino Valley will further deplete the flow of the Verde River, will potentially harm critical habitat for endangered species, and will injure downstream water rights. Document prepared by SRP. View Document.

Hydrogeology of the Upper and Middle Verde River Watersheds, Central Arizona

The upper and middle Verde River watersheds in central Arizona are primarily in Yavapai County, which in 1999 was determined to be the fastest growing rural county in the United States; by 2050 the population is projected to more than double its current size (132,000 in 2000). This study combines climatic, surface water, groundwater, water chemistry, and geologic data to describe the hydrogeologic systems within the upper and middle Verde River watersheds and to provide a conceptual understanding of the ground-water flow system. The study area includes the Big Chino and Little Chino subbasins in the upper Verde River watershed and the Verde Valley subbasin in the middle Verde River watershed. USGS report by Kyle Blasch. View Document.

Investigation of the Geology and Hydrology of the Upper and Middle Verde River Watershed of Central Arizona: Summary Report

In 1999, the U.S. Geological Survey (USGS), in cooperation with the Arizona Department of Water Resources (ADWR), initiated a regional investigation of the hydrogeology of the upper and middle Verde River watershed. The project is part of the Rural Watershed Initiative (RWI), a program established by the State of Arizona and managed by the ADWR that addresses water supply issues in rural areas while encouraging participation from stakeholder groups in affected communities. The USGS is performing similar RWI investigations on the Colorado Plateau to the north and in the Mogollon Highlands to the east of the Verde River study area (Parker and Flynn, 2000). The objectives of the RWI investigations are to develop: (1) a single database containing all hydrogeologic data available for the combined areas, (2) an understanding of the geologic units and structures in each area with a focus on how geology influences the storage and movement of ground water, (3) a conceptual model that describes where and how much water enters, flows through, and exits the hydrogeologic system, and (4) a numerical ground-water flow model that can be used to improve understanding of the hydrogeologic system and to test
test the effects of various scenarios of water-resources development. In 2001, Yavapai County became an additional cooperator in the upper and middle Verde River RWI investigation. View Document.

Laurie Wirt Presentation

Semiarid Big and Little Chino valleys are undergoing rapid growth, their populations solely dependent solely on ground water. Although the basins contain considerable amounts of ground water, from a historical perspective, groundwater overpumping in excess of safe yield inevitably leads to reduction or loss of perennial streams. The source of base flow to the Upper Verde River is the discharge from two basin-fill aquifers---the Big Chino basin-fill aquifer and the Little Chino basin-fill aquifer. Maintaining this discharge is critical toward maintaining base flow in the upper Verde River which is in turn critical for to maintain base flow for grandfathered downstream surface-water users in Verde Valley and Phoenix as well as for the maintenance of fish and game in some of the best remaining wildlife habitat in the State.
The goal of my talk today is to summarize some of the results of a recent USGS study1 on the geologic framework of the Verde River headwaters in the hope that a better understanding of the hydrologic system will help to clarify the science and lead to more informed decision making by stakeholders and the voting public regarding water resources. View Document.

Native Fish Monitoring in upper Verde River 2022

Results of native fish monitoring on upper Verde River show a serious decline in species and population. View this document.

Northpoint High School Verde Project

When ninth- grade students at the Northpoint Expeditionary Learning Academy in Prescott study the Verde River, they really study the Verde River.
They not only spend an entire semester on a single subject in a wide variety of classes, but they also integrate that subject into real-world examples in their hometown.
CWAG facilitated the Northpoint Verde project with classroom presentations and field trips. View Document.

Potential Future Declines in Base Flow to the Upper Verde River Due to Groundwater Extraction

This report builds on earlier work by the USGS in cooperation with the Arizona Department of Water Resources and Yavapai County to develop a regional flow model for northern Arizona. The USGS, in conjunction with the Verde River Basin Partnership (VRBP) and the Town of Clarkdale, subsequently applied the model in a series of simulations to gain a greater understanding of the past and potential future human impacts on the Middle Verde River's streamflow.

The work discussed in this paper was carried out to: (A) test the accuracy and predictive capability of the model within the Big Chino and Little Chino sub-basins; (B) illustrate the historical change in base flow at the USGS Paulden and Clarkdale streamgages; and (C) perform forward-looking simulations for the period 2005-2110 that evaluate potential effects on base flow in the upper Verde River resulting from; (1) unchanged water demand from 2005 through 2110, (2) continuing drought, (3) increased water demand, (4) extraction of the ADWR allocated 12,000 acre-feet per year (ac-ft/yr) of groundwater from the central part of the Big Chino sub- basin beginning in 2020, and (5) the cumulative effect of cases (1) through (4).

My testing of NARGFM showed that excellent agreement was found between historically observed and simulated groundwater elevations within the area of concern. In addition, simulated trends in both groundwater elevation and discharge to the Verde River are accurate to within industry-standard ranges.

My forward-looking simulations using the NARGFM show that the cumulative effect of continuing drought, increased water demand, and extraction of 12,000 ac-ft/yr (16.6 cfs) of groundwater from the Big Chino, will decrease the base flow to the Verde River by 12.8 cfs at the Paulden streamgage by the year 2110. Since the base flow at the Paulden streamgage in 2005 was approximately 19 cfs, this would leave only 6.2 cfs in the river. View Document.

Author: Peter Kroopnick, PhD. Revised April, 2015

 

Predevelopment interconnection of surface and ground water along Big Chino Wash

The planform pattern of Big Chino Wash provides information on past streamflow characteristics that created the floor of Big Chino Valley. The valley floor, and thus the bed and bank of the wash channel, is composed of sediment transported by the wash. The shape of the alluvial channel is uniquely produced by the type of streamflow. For example, a pattern of meandering stream channels, when viewed from above, is uniquely produced by perennial or intermittent flow that is interconnection with underlying groundwater. In Arizona, the resulting saturated floodplain Holocene alluvium is defined as the subflow zone. Appropriable water includes surface water and subsurface water of the subflow zone. Thus, the present geomorphology of Big Chino Wash contains information of past streamflow and groundwater conditions that is useful to water managers, river engineers and hydrologists.
Analysis by Win Hjalmarson, PE, USGS Ret. View Document.

Protecting the Verde River

Presentation slides summarizing the values of and the threats to the upper Verde. View Document.

Reconnaissance Watershed Analysis on the Upper and Middle Verde Watershed

The quantity, quality, and timing of water generated in the watershed is the result of land uses and condition at smaller scales. Grazing, fire suppression, timber harvesting, roads, mining, urbanization, and other human uses have resulted in significantly changed hydrologic condition. Prepared by Lloyd Barnett and Richard Hawkins, U of A. View Document.

Regional Groundwater-Flow Model of the Redwall-Muav, Coconino, and Alluvial Basin Aquifer Systems of Northern and Central Arizona (NARGFM)

Results of a major effort by USGS: a numerical flow model of the groundwater flow system in the primary aquifers in northern Arizona was developed to simulate interactions between the aquifers, perennial streams, and springs for predevelopment and transient conditions during 1910 through 2005. Simulated aquifers include the Redwall-Muav, Coconino, and basin-fill aquifers. Perennial stream reaches and springs that derive base flow from the aquifers were simulated, including the Colorado River, Little Colorado River, Salt River, Verde River, and perennial reaches of tributary streams. Simulated major springs include Blue Spring, Del Rio Springs, Havasu Springs, Verde River headwater springs, several springs that discharge adjacent to major Verde River tributaries, and many springs that discharge to the Colorado River. View Document.

Report on options for water management strategies

Report by the WAC on options for water management. View Document.

Response to Critique…

We don't like bullies. Adults shouldn't abuse children, and lawyers shouldn't pick on law students—unfairly. Yet, that's what happened in these pages in February, when Colleen M. Auer, an attorney in Arizona, attacked a former student of ours, Meredith Marder, for her Note, The Battle to Save the Verde: How Arizona's Water Law Could Destroy One of Its Last Free-Flowing Rivers, 51 Ariz. L. Rev. 175 (2009). View Document.

Sources of springs supplying base flow to the Verde River headwaters, Yavapai County, Arizona

Multiple lines of evidence were used to identify source aquifers, quantify their respective contributions, and trace the ground-water flow paths that supply base flow to the uppermost reach of the Verde River in Yavapai County, Arizona. Ground-water discharge via springs provides base flow for a 24-mile long reach from the mouth of Granite Creek (river mile 2.0) to Perkinsville (river mile 26). The flowing reach is important to downstream water users, maintains critical habitat for the recovery of native fish species, and has been designated a Wild and Scenic River. Sources of base flow are deduced from (a) geologic information, (b) ground-water levels, (c) precipitation and streamflow records, (d) downstream changes in base-flow measurements, (e) hydrologic analysis of water-budget components, and (f) stable- isotope geochemistry of ground water, surface water, and springs. Combined, this information clearly indicates that interconnected aquifers in Big Chino Valley are the primary source of Big Chino Springs, presently supplying at least 80 percent of the upper Verde River's base flow. Published by USGS; author Laurie Wirt. View Document.

SRP Groundwater Flow Model for the Big Chino Valley

SRP consultants prepared a Big Chino groundwater flow model showing that groundwater pumping in the Big Chino would substantially diminish the Verde River. View Document.

State of the Verde River: Water Quality

The Sierra Club Water Sentinels have implemented a volunteer water quality and flow monitoring program on the Verde River. Teams of Water Sentinels volunteers have collected water samples, made field measurements of water quality parameters, and measured the flow of the river at six to eight sampling sites on the Verde River over the last five years. The data summarized in this report was collected between December 2, 2006, and December 10, 2011. The suite of water quality parameters include E. coli bacteria, total arsenic, total nitrogen, total phosphorus, and suspended sediment concentration. Water Sentinels also made field measurements of dissolved oxygen concentration, pH, electrical conductivity, total dissolved solids, and air and water temperature. They collected hundreds of water samples at six to eight sampling sites along the upper and middle reaches of the Verde River during all seasons in the five‐year period, visiting sampling sites on the Verde River five or six times each calendar year. View Document.

Studies and Experts Agree: Withdrawing Groundwater from the Big Chino Valley Will Reduce Flow in the Verde River!

Sustainable Water Management in the Southwestern United States: Reality or Rhetoric?

While freshwater sustainability is generally defined as the provisioning of water for both people and the environment, in practice it is largely focused only on supplying water to furnish human population growth. Symptomatic of this is the state of Arizona, where rapid growth outside of the metropolitan Phoenix-Tucson corridor relies on the same groundwater that supplies year-round flow in rivers. Using Arizona as a case study, we present the first study in the southwestern United States that evaluates the potential impact of future population growth and water demand on streamflow depletion across multiple watersheds.
We modeled population growth and water demand through 2050 and used four scenarios to explore the potential effects of alternative growth and water management strategies on river flows. Under the base population projection, we found that rivers in seven of the 18 study watersheds could be dewatered due to municipal demand. Implementing alternative growth and water management strategies, however, could prevent four of these rivers from being dewatered.
The window of opportunity to implement water management strategies is narrowing. Because impacts from groundwater extraction are cumulative and cannot be immediately reversed, proactive water management strategies should be implemented where groundwater will be used to support new municipal demand. Our approach provides a low-cost method to identify where alternative water and growth management strategies may have the most impact, and demonstrates that such strategies can maintain a continued water supply for both people and the environment.
Published by The Nature Conservancy. View Document.

Sustainable Water Management: Guidelines.

Sonoran Institute report detailing the importance of riparian habitat, the impacts of groundwater mining, and offering a framework for sustainable water management. Case studies of the upper San Pedro River, the upper Santa Cruz River, and the upper Verde River. 52 pages. View Document.

The Battle to Save the Verde: How Arizona’s Water Law Could Destroy One of Its Las Free-Flowing Rivers

This Note explores a battle for water in the Southwest that may ultimately destroy one of Arizona's most precious rivers. This struggle pits the doctrine of reasonable use against the doctrine of prior appropriation and exposes the need to reconcile the uniquely Arizonan concept of "subflow," which purports to synthesize the laws of ground and surface water, with scientific reality. The characters in this complicated battle include rural municipalities that plan to pump from the river's headwaters, a major metropolitan utility company with century-old rights to the river, and an environmental advocacy organization seeking to protect endangered species. The plight of the Verde River exemplifies what has become a common tale in the United States—multiple parties with valid rights to the same water under different laws. Its resolution will likely require some difficult decisions about resource allocation, rural and urban growth, and the courts' willingness to side with science in the face of impossibly high stakes and a river in peril. By Merideth Marder, published in the Arizona Law Review. View Document.

The Verde river – A Desert Treasure at Risk

A 4 page informational brochure written by the Verde River Basin Partnership: "The Verde River is an irreplaceable treasure viewed as unique by people around the world. Unfortunately, the continued existence of its year-round flow and the life and lifestyles it supports are at risk." Published by the Verde River Basin Partnership. View Document.

Understanding Arizona’s Riparian Areas

Report from the U of A Extension describing Arizona's riparian areas and their importance to the landscape. View Document.

Upper Verde River Habitat Analysis Executive Summary 2020 - 2023

The US Forest Service Rocky Mountain Research Service in Flagstaff published “Upper Verde River Habitat Analysis Executive Summary 2020 - 2023” in late 2023. The report is rich in data for the upper Verde: lidar surveys, transects of vegetation and channel structure, instream habitats, and E-DNA for fish. View this report.

Upper Verde, Wild and Scenic River, A Citizens' Proposal, Executive Summary, August 2011

The Executive Summary for the Citizens' Proposal. View document.

Verde River Base Flow

Graph of base flow along the river from headwaters to Camp Verde taken from the Blasch report. View Document.