USGS Present & Future ChallengesThe U.S. Geological Survey

Water-Resources Data Program

Although the total number of gauging stations remains fairly constant, the number in undeveloped areas or with greater than 50 years of record continues to decline.

Since its establishment in 1879, the U.S. Geological Survey has collected water data that are used

by stakeholders and decision makers to minimize loss of life and property and to manage and protect groundwater and surface-water resources for a variety of uses. Users of USGS data represent essentially all hydrologic sectors, including regulators, researchers, consultants, lawyers, policy makers, and conservationists, as well as other scientists, agencies, recreators, and others.

Early Stations Retain Their ValueUSGS established its first streamflow-gauging station in 1889 on the Rio Grande near Embudo, New Mexico; the streamflow-gauging program now includes more than 7,000 continuous-record stations in the United States and its territories. More than 90 percent of the stations are supported at least partially by other federal, state, and local cooperators (Wahl and others, 1995), and many likely would not be operated without such support. Although the total number of gauging stations remains fairly constant, the number in undeveloped areas or with greater than 50 years of record continues to decline.

Streamflow data from long-term stations are critical to assess climate variability, anthropogenic impacts on water resources, and hydrologic trends. For example, trend analysis of the 102-year streamflow record from the San Pedro River at the Charleston, Arizona gauging station allowed USGS to determine that annual flow diminished by more than 50 percent during the period of record. In other areas, multiple regression analysis is used to develop equations for “regional relations” that relate stream discharge

to basin area, mean elevation, and mean annual precipitation. Once developed, such relationships can be applied to ungauged streams within a defined hydrologic area (Wahl and others, 1995).

Surface and Groundwater DataUSGS maintains a national database of more than 850,000 station years of time-series surface water data that describe stream levels, streamflow, reservoir and lake levels, and rainfall. Data are collected in the field or relayed by telecommunications for storage and processing. Data from 8,160 stream gauges are relayed through satellite telemetry, processed automatically, and are available online within minutes.

USGS also provides regional evaluations, baseline and time series data, and predictive tools to help promote the sustainability of groundwater resources, particularly in areas at risk from overuse and contamination. Groundwater-level data are collected at approximately 25,000 stations nationwide. When spatial area studies are conducted, supplementary water-level data occasionally are collected on a shorter-term basis. USGS maintains a groundwater database of more than 850,000 records of wells, springs, test holes, tunnels, drains, and excavations.

Water Quality Data and MonitoringUSGS collects water quality data from thousands of groundwater, stream, and lake stations. The specific parameters measured vary by location, but at selected surface-water and groundwater sites, instruments continuously

record pH, specific conductance, temperature, dissolved oxygen, and percent dissolved-oxygen saturation. Air temperature and barometric pressure are also available at some sites. At about 1,230 stations from which this information is transmitted automatically, data are available from the real-time data system. USGS also maintains a database of more than 4.2 million water quality analyses collected by its districts for various projects.

USGS’s National Water-Quality Assessment Program (NAWQA) focuses

on water quality in major river basins and aquifer systems. The program addresses national- and regional-scale questions such

as: What is the condition of our streams and groundwater? What are the factors affecting the condition? Is water quality changing over time? The NAWQA data warehouse currently contains data on:

• chemical concentrations in water, bed sediment, and aquatic organism tissues for about 600 chemical constituents

• site, basin, well, and network characteristics

• daily streamflow information for fixed sampling sites

• groundwater levels for sampled wells

• 7,600 surface-water sites and 8,100 wells

• 48,000 nutrient samples, 30,000 pesticide samples, and 8,800 volatile organic compound samples

• 2,600 samples of bed sediment and aquatic organism tissues.

Jeff Phillips and Nick Melcher – U.S. Geological Survey

18 • May/June 2006 • Southwest Hydrology

USGSNew Instruments and Dissemination MethodsUSGS maintains the National Water Information System (NWIS), a distributed network of computers and fileservers, to store and retrieve water data. NWISWeb provides an interface for both the public and agency users to access a large volume of USGS water data maintained on 48 separate NWIS databases nationwide. Data are regularly updated from NWIS sites; real-time data are transmitted to NWISWeb several times daily. NWISWeb provides numerous output options, including real-time streamflow, water-level and water-quality data graphs, and station location maps.

In recent years, USGS has employed advanced technologies to improve the reliability of streamflow-gauging instrumentation, reduce the time required for field measurements, and extend the range and scope of the data-collection network.

The Acoustic Doppler Current Profiler (ADCP) sits on the river surface and bounces sound waves off sediments and debris to produce detailed measurements of flow velocities and cross sections in a fraction of the time required for standard streamflow metering. It enables measurements to be made of some waters otherwise not feasible. USGS is working with private sector vendors to improve this technology and increase its applicability to a wider range of riverine environments.

USGS’s Hydro 21 Committee was tasked with developing a method to monitor river discharge by noncontact (out of the water)

methods using sensors mounted on river banks. Several successful velocity experiments were conducted on the San Joaquin and Cowlitz rivers using varying radar wavelengths. Together with University of Michigan research that uses multi-position long-wave-length radar to measure river depth, this new radar-based approach has the potential to provide accurate discharge and channel cross-section information without the need for frequent discharge measurements for stage recalibration.

Financial Constraints versus Long-term NeedsThe “shared support” basis for the USGS hydrologic network has been effective at distributing the program’s financial burden among the many users of the data. Cooperators pay a relatively small portion

see USGS, page 31

Above: Bank-mounted radar for continuous river veolocity measurement, San Joaquin, California. Right: Locations of USGS stream gauges in the West illustrating the relative dearth in less-developed regions.

Water Resources Data Arizona Water Year 2005, by G.G. Fisk, N.R. Duet, E.H. McGuire, W.P. Roberts, N.K. Castillo, and C.F. Smith. http://pubs.usgs.gov/wdr/2005/wdr-az-05-1/

Lithology and thickness of the Carmel Formation as related to leakage between the D and N aquifers, Black Mesa, Arizona, by Margot Truini and J.P. Macy. http://pubs.usgs.gov/sir/2005/5187/

Evaluation of Metal Loading to Streams near Creede, Colorado, August and September 2000, by B.A. Kimball, R.L. Runkel, K. Walton-Day, and B.K. Stover. http://pubs.usgs.gov/sir/2004/5143/

Water Resources Investigations at Edwards Air Force Base since 1988, by Michelle Sneed, Tracy Nishikawa, and Peter Martin. http://pubs.usgs.gov/fs/2005/3112/

May/June 2006 • Southwest Hydrology • 19

see Critical Need, page 31

Water Resources Investigations Budgets

2005 ($ million)

2006 ($ million)

2007 request ($ million)

Hydrologic Monitoring, Assess, & Research

NSIP portion

142.5

13.8

142.5

14

141.8

16.76

Cooperative Water Program 62.3 62.8 62.2

Water Resources Research Institutes Program

6.4 6.4 0

Total, Water Resources 211.2 211.7 204

From USGS Budget in Brief and usgs.gov/budget/2006/fy06_justification.html

USGS Feels the Pinch The Bush Administration’s budget request for 2007 of $204 million for the USGS Water Resources Program represents a decrease in funding of $7.7 million. Changes in funding to major programs are summarized below. The 2007 request represents a $2.3 million increase for stream-gauging to add 30 real-time gauges to the network and a $940K decrease for the National Water Quality Assessment program.

National Streamflow Information Program (NSIP)

• One of its design components was to “provide a ‘backbone’ or core of streamgauges that are of such critical importance to national streamflow information needs that their operation should be assured with Federal funds.”

• 13 percent of network stream gauges are federally funded.

• In the Southwest for 2005 and 2006, Arizona had one stream gauge discontinued (Laguna Creek at Denehotso, with 10 years of data). Eight gauges were discontinued in Colorado, one with a 56-year record (Cherry Creek below Cherry Creek Lake).

Cooperative Water Program

• Originally had 50 percent federal support, now 33 percent.

• More than 20 professional water organizations and NGOs sent a letter to Secretary of Interior Gale Norton and David Anderson, Associate Director, Natural Resource Programs, Office of Management and Budget requesting $74 million for FY 2007 to restore purchasing power to FY 2003 level.

From 1980 to 2004, 2,051 streamflow gauges with records of 30 years or more were discontinued. (Source: water.usgs.gov/nsip/history_slide6.html)

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USGS, continued from page 19

Critical Need, continued from page 21

of the cost of the total network but enjoy equal access to the entire hydrologic database. Nearly all of the network data are accessed and used by multiple sources.

This financially opportunistic process for supporting the hydrologic network provides parity for support; however, it also creates some systemic program limitations. Financial support for a gauging station generally is dependent on two factors: a management issue of sufficient importance to justify the construction and continuing support for a network station, and the availability of discretionary tax revenues. These requirements tend to bias the establishment of stations in developed and densely populated areas (see map, page 19). While this benefits highly populated regions which are generally near critical locations for river discharge accounting, it causes network gaps in less-developed regions. Funding restrictions also create a bias toward regulated or

managed rivers. Diversions, withdrawals, and regulation of water use are usually responsible for hydrologic issues deemed sufficient to justify river gauging. Consequently there is a dearth of network stations and corresponding hydrologic data to represent undeveloped conditions.

We are only beginning to fully understand the value of long-term databases and the important role they play. Stations that have been operated for 50 years or more provide insight on hydrologic conditions and trends that may not be available from any other source. Natural climatic wet and dry periods as well as climate change occur in cycles of decades or more, and long-term records are essential to detect real trends and impacts on water resources.

Unfortunately, too many data recorders and data collection sites in the USGS network are discontinued or relocated when the issue that motivated their establishment matures or is resolved

and/or cooperative funding is no longer available. Consequently, too few areas have long-term surface-water records. This is particularly true of undisturbed areas, from which long-term basin and climatologic inferences could be drawn. Nevertheless, USGS remains committed to providing high-quality data for a multitude of users, and in recent years the agency has received appropriated resources that at least temporarily have helped reverse the decline of numbers of long-term stations.

Contact Jeff Phillips at jvphill@usgs.gov.

USGS Data WebsitesReal-time and historic surface-water, groundwater, and water-quality data from NWISWeb: waterdata.usgs.gov/nwis/; use sw/, gw/, or qw/ extensions, respectively.

NAWQA data warehouse: infotrek.er.usgs.gov/traverse/f?p=NAWQA:HOME:2200096155959254017

ReferenceWahl, K.L., W.O. Thomas, and R.M. Hirsch, 1995. An

overview of the streamflow-gauging program, U.S. Geological Survey Fact Sheet FS-066-95.

Administration for $16.2 million for NSIP and $74 million for CWP, along with significant future increases. The President’s FY2007 budget request includes $16.8 million for NSIP—an increase of $2.8 million over FY2006—but only $62.2 million for CWP—representing a cut of $2 million to CWP interpretive studies. Neither the NSIP nor CWP requests include enough money to fully offset anticipated federal cost increases.

On Sept. 30, in a letter to then-Interior Secretary Gale Norton and Joshua Bolten, director of the Office of Management and Budget, ten U.S. senators called for a much more ambitious effort to increase spending on CWP and NSIP by $180 million over the next five years, with minimum annual increases of $15 million and $20 million respectively. The letter stated, “Over the last seven years, Congress and the Administration have struggled to understand and achieve a balance in the appropriate federal investment in the collection and management of water resources data.” It continues listing various federal programs, as well as events and

circumstances, that require good water data, including multi-decade droughts, dramatic increases in water demands due to population growth, regional impacts of climate change, river management impacts on ocean environments, monitoring river health, understanding required total maximum daily [pollutant] loads (TMDLs), hydropower production, and real-time flood warning and emergency response.

WSWC also supports other data-related initiatives, including enactment of a National Drought Policy bill introduced by Senator Pete Domenici and the related creation of a National Integrated Drought Information System (NIDIS). NIDIS would facilitate public access to real-time data and help water users and others anticipate and mitigate drought-related impacts. The WGA is leading efforts to make NIDIS a reality, with or without authorizing legislation (see www.westgov.org/wga/initiatives/drought/).

Further, the council has urged the Administration to ensure the next generation of Landsat instruments is capable of thermal imaging and observations at a resolution sufficient

for continuing calculations of evapotranspiration that increasing numbers of states are using to monitor water use and improve water management. The current Landsat 5 and Landsat 7 satellites provide valuable data, but age and equipment malfunctions limit their future reliability. The President’s Office of Science and Technology Policy recently directed NASA to acquire a single Landsat data continuity mission in the form of a free-flyer spacecraft to collect land surface data and deliver it to USGS. Reportedly, $98 million is in the 2007 request for this purpose, but the “actively cooled thermal sensor technology” used in the Landsat 7 spacecraft was a large factor in the overall cost of both systems and is no longer a firm baseline requirement.

It will take a significant grassroots effort from all those with a stake in the quantity and quality of hydrologic data in the West to raise the political will necessary to produce the information we will need to assess and address our future water resources challenges.

Contact Tony Willardson at twillards@wswc.state.ut.us.

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