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The U.S. Geological Survey (USGS) collects, compiles, and disseminates data
on water, energy, biological resources, and mineral resources in Nebraska.
The USGS is known for its unbiased data collection and research-gathering,
interpreting, and presenting data that enable resource planners and others
to make decisions that are based on objective information. As the Nation's
leading earth science agency, the USGS works cooperatively with Federal,
State, and local agencies to address issues related to Nebraska's earth
resources. Today's issues are more pressing than ever-the continuing need
for resource development, describing and predicting the fate of
contaminants, and understanding the effects of human activities on
resources. |
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The Sand Hills region, which covers nearly the western one-third of the
State, is the largest dune field, stabilized or active, in the Western
Hemisphere. Studies indicate that in this region, there may be a potential
for "desertification," a term that refers to productive land changing to
nonproductive land as a result of natural processes or human activities.
In the Sand Hills, vegetation is the principal factor that contributes to
stability of the dunes. Without soil and vegetative cover, stable and
productive sand dunes may become mobile and nonproductive. If the sand
dunes are reactivated, then potential consequences include destruction of
important grazing land; movement of dune sand onto productive cultivated
land and (or) major transportation routes, such as U.S. Interstate 80 and
railroads; interference with commuter aircraft departures and arrivals; and
destruction of wetlands, which would have severe effects on wildlife.
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The USGS is mapping the region and determining the ages of the dunes,
particularly the most recent episodes of dune activity; the origin of the
sand; and the climatic conditions at the time of dune movement. The USGS
works closely with scientists at the Conservation and Survey Division of
the Institute of Agriculture and Natural Resources (CSD), the Department of
Geology, and the High Plains Climate Center, all located at the University
of NebraskaŠLincoln (UNL). |
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Grassland fires pose a serious threat to agricultural and urban areas when
grasses become dry owing to hot, dry, and windy weather conditions. In
response to a need for timely information on grassland conditions, the USGS
provides weekly vegetation condition, or "greenness," information derived
from satellite data to the Nebraska Forestry Service. Vegetation
conditions vary by county on a weekly basis, from high (green tones) to low
(yellow and red tones). Given specific weather conditions (hot, dry, and
windy), the grassland fire danger can reach the severe and extreme category
where vegetation conditions are in the low category (fig. 1). The
greenness information is sent to the National Weather Service in Omaha
where it is combined with daily weather information to forecast fire danger
conditions. When severe conditions exist, information is provided to
emergency monitoring centers and the news media for broadcast to the
public. |
(Click on image for a larger version, 50K GIF)
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Figure 1. Vegetation conditions in Nebraska, Green
represents high vegetation, yellow and red are associated with low
vegetation. | |
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Statewide information on the magnitude and frequency of flooding is
required by bridge designers, flood-plain managers, and others to ensure
public safety and to enable cost-effective bridge design. The USGS, in
cooperation with the Nebraska Department of Roads (DOR) and the Federal
Highway Administration (FHWA), is updating the techniques for estimating
maximum streamflows throughout the State by using flood data through 1993.
Characteristics, which include drainage basin size and shape, soils,
topography, drainage network, and climate, are being compiled for drainage
basins upstream from the gaging stations by using a geographic information
system, improved analytical procedures, and a computer program developed by
the USGS. Regional and State flood frequency equations, which are based on
traditional and nontraditional techniques, are being developed or updated
to relate flood discharges to basin characteristics. These equations can
be used to estimate the flood potential within ungaged basins throughout
the State that have similar basin characteristics. In addition, a network
analysis of the flood-gaging network is being conducted to determine where
additional data collection could most improve future flood-frequency estimates. |
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The interior parts of continents are usually considered to be tectonically
and seismically stable. However, recent surface-rupturing earthquakes in
the United States, as well as in other parts of the world, raise concern
for many States, including Nebraska, that are normally considered to be
aseismic. The long-term behavior of faults in such areas is poorly known
despite the potential threat that these faults may pose to populated
regions. Additional studies of the history of Quaternary age faulting in
stable continental regions are needed to characterize their short- and
long-term behavior and to improve earthquake-hazard assessments in these
largely aseismic areas.
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The USGS is studying several suspected faults in Nebraska. One is exposed
on the south shore of the Harlan County reservoir, southeast of Alma, and
the second is just northeast of Ord. This study is one of many supported
by the Nuclear Regulatory Commission. The objective of these studies is to
provide paleoseismic data on suspected but unstudied faults in the stable
central interior of the United States. Preliminary results from these
studies show that faults can remain dormant for thousands of years, and
then fail with little or no precursory seismic warning. Many of these
faults are reactivated structures commonly associated with ancient rifts or
suture zones that are within regionally uniform stress fields, driven by
plate tectonic forces. |
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Nebraska has some of the most intensively cultivated and irrigated land in
the Nation. As a result, ground water has become contaminated by
agricultural chemicals in some areas. As part of their
ground-water-management plans, each of Nebraska's 23 Natural Resources
Districts (NRD's) is required to identify locations and concentrations of
ground-water contamination and to monitor levels of selected contaminants.
Many NRD's have established "ground-water management areas" where
nonpoint-source contamination problems can be managed through the
regulation of chemical and water applications or through other appropriate
best-management practices. The establishment of such areas is underway in
several additional NRD's as well.
In 1990, the USGS began a cooperative program to conduct a water-quality
reconnaissance in selected NRD's. The resulting data help the NRD's to
fulfill their responsibilities. The USGS either has completed or is
conducting ground-water-quality investigations in the Nemaha, the North
Platte, the Papio-Missouri River, and the Lower Platte South NRD's (fig.
2). |
Under an alternative procedure, the State has designated some areas that
are particularly susceptible to nitrate contamination of ground water as
Special Protection Areas (SPA's). As part of this desig-nation, NRD's are
required to establish ground-water-quality-monitoring networks within the
SPA's. These networks can be used to determine water-quality changes that
result from alternative land-management practices. The USGS has completed
or is currently involved in three SPA water-quality investigations in the
Superior, the Upper Big Blue, and the Red Willow-Hitchcock areas (fig.
2).
(Click on image for a larger version, 50K GIF)
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Figure 2. Special Protection Areas and Natural Resource
District cooperative project study areas in Nebraska. |
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Among the most popular and versatile products of the USGS are its
1:24,000-scale topographic maps (1 inch on the map equals 2,000 feet on the
ground). These maps depict basic natural and cultural features of the
landscape, such as lakes and streams, highways and railroads, boundaries,
and geographic names. Contour lines are used to depict the elevation and
shape of terrain. Nebraska is covered by 1,427 maps at this scale, which
are useful for civil engineering, land-use planning, natural-resource
monitoring, and many other technical applications. These maps have long
been favorites with the general public for outdoor recreational uses,
including hiking, camping, hunting, exploring, and back-country fishing
expeditions. |
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statemap is one of the external funding opportunities offered by the USGS
National Geologic Mapping Program; agreements are open to all 50 State
Geological Surveys. Typically, the Program focuses on such issues as
ground-water quality and geologic hazards. The Program also addresses a
range of resource issues, such as oil and gas assessments, coal quantity,
sand and gravel resources, and economic mineral development. Geologic map
data generated are archived at the State Geological Survey and within the
National Geologic Map Data Base. |
Work is currently continuing on the Alliance and the O'Neill
1:250,000-geologic maps. Preliminary geologic mapping in urban areas in
eastern Nebraska is beginning. |
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The State Geological Surveys of Nebraska, Iowa, Kansas, and Missouri and
the USGS have formed a partnership to conduct geologic studies that concern
land-use issues in the Middle Missouri Basin. These studies are being
conducted in a corridor that encompasses Omaha and Lincoln, Nebraska,
Council Bluffs, Iowa, Kansas City, Missouri, and Kansas and Topeka, Kansas.
Most of the areas between the cities consist of smaller urban centers and
intervening rural areas that support intensive agricultural activities. |
Geologic constraints, such as collapsing or expanding soils, landslides,
subsidence, and flooding, affect land use and present other problems,
especially in urban areas. Disposal of municipal and industrial wastes,
which include hazardous waste, is of concern in terms of past practices and
future needs. Erosion, sedimentation, and contamination from nonpoint
sources are major issues in areas of agricultural and urban development.
Geologic information obtained in these studies is essential to
understanding the carrying capacity of the land, identifying potential
consequences of land uses on the natural system, and determining methods to
reduce or mitigate these consequences. |
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Many stream channels in eastern Nebraska were altered in the early 1900's
to help alleviate flooding. Channel straightening has long been recognized
as a cause of channel-stability problems, such as downstream deposition and
upstream degradation and widening of the channel, which pose hazards to
roads and bridges. In addition, the channel banks, which comprise highly
erodible soils, were severely eroded by the floods of 1993. Many small
county bridges failed or were closed as a result of the floods.
The USGS, in cooperation with the PapioŠMissouri River and the Lower Platte
South NRD's, the DOR, the Nebraska Natural Resources Commission (NRC), the
FHWA, the UNL, the Agricultural Research Service, and the U.S. Army Corps
of Engineers, is examining the effects of channel instabilities on bridge
structures and flood-plain resources in a 23-county area of eastern
Nebraska. |
Improved methods for anticipating future channel stability and geometry and
the identification of possible types of remediation measures to stabilize
the channels will benefit planners, structural designers, and resource
managers by helping them make optimal economic use of resources in and near
flood plains. |
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Flood and drought conditions may adversely affect wildlife habitat, human
activity, and crop production. The USGS, in cooperation with more than 25
Federal, State, and local agencies, collects streamflow data at numerous
sites throughout the State. These data are critical for administering and
managing water resources, determining the extent and severity of droughts,
characterizing and predicting conditions during floods, and monitoring the
effects of human activities on streamflow. In addition, the USGS collects
water-quality information at surface- and ground-water sites throughout
Nebraska as part of its cooperative program. Water-resource managers use
these data to evaluate the suitability of water as a source of supply for
specific uses and to monitor the effects of human activities on water
quality. The USGS also compiles and reviews ground-water level data
collected annually or semiannually by State or local agencies from more
than 4,000 wells and from about 100 wells monitored continuously. These
data are used to monitor changes in ground-water quantity and to provide a
basis for sound ground-water management decisions in the State. |
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The National Water-Quality Assessment (NAWQA) Program was established by
the USGS to provide a hydrologically based, long-term method of assessing
the quality of a large representative part of the Nation's water resources.
A multidisciplinary approach to data collection (physical, chemical, and
biological) is used to provide an integrated assessment of water quality
within selected environmental settings, to assess trends in water quality,
and to investigate the influence of natural and human factors on water
quality over time. Water-quality information produced through the NAWQA
Program will be useful to policymakers and water managers at Federal,
State, and local levels. Two NAWQA Program studies are underway in
Nebraska-the Central Nebraska and the South Platte Basins.
Selected results from the Central Nebraska Basins study (fig. 3) relate to
water quality. Herbicides (atrazine and cyanazine) widely used in the
production of row crops, especially corn, are found in many streams in
concentrations large enough to exceed the U.S. Environmental Protection
Agency (USEPA) drinking water standard. Concentrations decrease
significantly as the growing season progresses. These herbicides also are
found in ground water but at concentrations that are much smaller than in
surface water and seldom if ever exceed the drinking water standards.
Nitrate is commonly found at concentrations that exceed the USEPA drinking
water standard in shallow ground water in the Platte Valley (fig. 3),
where large quantities of fertilizer are applied. Nitrate also is found in
area streams. Most public water supplies derived from ground water in the
Platte Valley are obtained from deeper wells that have smaller nitrate
concentrations or from wells close enough to the Platte River that
concentrations are diluted by infiltration of river water into the ground
water. |
(Click on image for a larger version, 752K JPEG)
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Figure 3. Subunits of the Central Nebraska Basin's study
unit, National Water-Quality Assessment Program. |
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The USGS produces digital cartographic data in cooperation with the NRC.
The data are useful for geographic information systems (GIS) analyses and
applications that address land-use, natural-resource management, and
environmental impact issues throughout the State. The USGS and the NRC
cooperatively produced new digital elevation models (DEM's) and digital
orthophotoquads (DOQ's) for Lancaster County in a recent pilot project.
DOQ's are prepared by scanning aerial photographs and processing to correct
for camera and relief distortion. DEM's portray the Earth's terrain as a
sampled array of elevation values and are used to correct for relief
distortion in the DOQ source photographs. They also are used as a major
data element in GIS analyses. The Lancaster County pilot project served as
the model for implementing a partnership agreement between the two agencies
to prepare new DEM's by using state-of-the-art production techniques and to
produce DOQ's for the entire State. |
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The Competitive Cooperative Agreements Program was established by the
Federal Geographic Data Committee (FGDC) through the USGS to help form
partnerships with the non-Federal sector that will assist in the evolution
of the National Spatial Data Infrastructure. This program provides funding
to State and local government agencies, academia, and the private sector to
encourage resource-sharing projects through the use of technology,
networking, and interagency coordination. A variety of agencies in
Nebraska, which include the Nebraska Library Commission and the Nebraska
Geographic Information Systems Steering Committee, are participating in the
Nebraska National Spatial Data Infrastructure Clearinghouse and Geospatial
Metadata Initiative Project. It was designed to establish and manage a
National Spatial Data Infrastructure clearinghouse node on the Internet, to
enhance the compatibility of existing geospatial data in Nebraska with FGDC
data standards; and to increase the awareness and use of the National
Spatial Data Infrastructure clearinghouse network and FGDC standards among
Nebraska['s geospatial data users. |
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The Earth Science Information Centers (ESIC's) provide information about
USGS programs, products, and technological developments to the public. The
ESIC in Lincoln was established under a cooperative agreement between the
USGS and the CSD. As part of the national ESIC network, this office
provides information on such earth science topics as cartography,
geography, digital data, remote sensing, geology, geophysics, geochemistry,
hydrology, geohydrology, aerial photography, and land use. It is supported
by the USGS with reference materials, technical assistance, training and
outreach activities, as well as access to USGS data bases. |
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Outreach is a USGS priority in Nebraska. It can be found in many forms,
such as participation in festivals (Children's Groundwater Festival, Earth
Wellness Festival, Earth Day), area grade/high school visits, visits to
classes at UNL, and participation in Women in Science activities. The USGS
works closely with The Groundwater Foundation; employees serve on its
National Review Board and committees and as mentors in its Groundwater
University Program. |
Many educational materials are available for educators and the public. The
USGS District Office in Lincoln has created a coloring book that describes
the hydrologic cycle, which is displayed on the District's home page on the
World Wide Web. Poster sets, pamphlets, and other educational materials
may be obtained from the ESIC in Lincoln. |
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The USGS Biological Resources Division (BRD; formerly the National
Biological Service) conducts research and provides the scientific data
needed for sustained economic benefits from and conservation of the
grassland ecosystems of the central Great Plains. BRD research activities
include documenting the wildlife values of the Conservation Reserve
Program, which removed about 36 million acres of marginal farmland
nationally from agricultural production and enhanced its value as food and
cover for wildlife. BRD also works with other USGS Divisions on the
development and implementation of a study of wetlands and water quality in
the North and South Platte Rivers and their tributaries, which are
critically important in the State for migratory birds and endangered
species. Another significant project is coordinating vegetation mapping
work at Scotts Bluff and Agate Fossil Beds National Monuments for the
National Park Service Inventory and Monitoring Vegetation Mapping Program,
which is a comprehensive project to map vegetation in 250 units of the
National Park System to provide information for natural resource managers.
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