United States
Environmental Protection
Agency
Office of Water
(4503F)
EPA841-B-99-006
December 1999
vvEPA
Remotely Monitoring Water Resources:
An EPA/NASA Workshop
-------
Acknowledgments
This document was compiled for the U.S. Environmental Protection Agency's Office of
Water with partial support under Purchase Order No. 9W-0492-NATX to Dr. Theodore
A. Endreny (now with SUNY College of Environmental Science and Forestry) and
Contract No. 68-C7-0018 to Tetra Tech, Inc. from the EPA Office of Wetlands, Oceans
and Watersheds AWPD Watershed Branch, and with partial support under Contract No.
68-C5-0065 to Lockheed Martin Environmental Services from the EEPA Environmental
Photographic Interpretation Center, National Exposure Research Laboratory. The EPA
Project Officer was Douglas J. Norton.
Notice
This document has not been administratively reviewed, and its contents do not
necessarily reflect the views or policies of the U.S. Environmental Protection
Agency, the National Aeronautics and Space Administration, or any other
organization mentioned within. Mention of trade names or commercial products or
events does not constitute endorsement or recommendation for use.
Where to obtain copies
Single copies can be ordered for free by calling 1-800-490-9198 and requesting
document number EPA841-B-99-006, "Remotely monitoring water resources: an
EPA/NASA workshop." The document in full is also found on the Internet at
http://www.epa.aov/owow/watershed/wacademv/its.html
This report should be cited as:
U.S. Environmental Protection Agency. 1999. Remotely monitoring water
resources: an EPA/NASA workshop. EPA841-B-99-006. Office of Water (4503F),
United States Environmental Protection Agency, Washington, DC. 101 pp.
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FOREWORD
In December, 1996, the U. S. Environmental Protection Agency (EPA) and the National
Aeronautics and Space Administration (NASA) brought together scientists and
managers from both agencies and their collaborating research organizations to discuss
the potential applications of existing and developmental remote sensing technologies to
water resources monitoring. The workshop planners crafted the following statement to
explain the workshop's aims and guide its participants:
WORKSHOP STATEMENT OF PURPOSE
Monitoring the condition or health of the environment is essential to its proper stewardship and
management. Under the Clean Water Act, water resources are monitored by states and other
jurisdictions, but current programs are unable to monitor all their watersheds, water bodies, and
point- and non-point pollution sources. In reality, the majority of U.S. water bodies are not
monitored regularly, and even more are not monitored as well as resource managers would like.
This is both a financial and technical problem, as many monitoring methods are not cost-
effective or technologically efficient enough for monitoring all water bodies of interest.
The rapid advancement of new technologies, such as remote sensing, may someday provide
methods for monitoring more water quality parameters, in more water bodies, with improved
accuracy, or with reduced per-unit costs. To actively improve the status of monitoring science,
however, monitoring professionals must learn about emerging technologies as well as those
available now, and researchers who develop these technologies must learn the needs of their
clientele. In order to focus and accelerate research and applications of advanced technologies
in water resources monitoring, the U.S. Environmental Protection Agency (EPA) and the
National Aeronautics and Space Administration (NASA) are convening a workshop to discuss
and match monitoring needs with the appropriate advanced technologies. The purpose of this
workshop is to expose technical and management personnel of both agencies to (1) NASA's
remote sensing science and technology, and (2) EPA's water resources monitoring requirements
and data bases. The goal of the workshop is mutual education, and the opportunity to explore
future collaboration in water monitoring/remote sensing research and applications.
Three years later, this workshop's findings continue to be relevant to water resources
monitoring and management. The challenges facing local, state and federal water
monitoring programs basically remain the same. The opportunities for NASA and its
collaborating researchers to apply remote sensing technologies to water resources
monitoring are still significant. Moreover, NASA's Mission to Planet Earth program, now
called Earth Science Enterprise, is considerably closer to applying new remote
technologies in 1999 than three years ago, and some of the collaborations suggested at
the workshop are already taking place. Accordingly the EPA Office of Water has
published this workshop report, with minor updates, to share its useful findings with
water resource managers and researchers.
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Workshop Co-Chairs
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Stephen A. Lingle
US EPA (8101)
401 M Street SW
Washington, DC 20460
Phone: 202-260-2619
Fax: 202-260-4524
linqle.stephentfb.epa.ciov
Douglas J. Norton
US EPA (4503F)
401 M Street SW
Washington, DC 20460
Phone:202-260-7017
Fax: 202-260-7024
no/ton. abt/q/as(S)epa. qov
Alexander J. Tuyahov
NASA HQ Code YS
300 E Street SW
Washington, DC 20546
Phone: 202-358-0250
Fax: 202-358-3098
atuvahov(g)ha.nasa.Qov
Discussion Group Co-Chairs
EPA: Barry Burgan
NASA: Ted Engman
EPA: Peter Stokely
NASA: Vic Klemas
EPA: Joe D'Lugosz
NASA: James Arnold
EPA: Joe Hall
NASA: James Voder
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Workshop Planning Group
Individual
Agency
NASA Headquarte/s
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Ted Engman
Joe Ha//
Vic Klemas
Tom Mace
Gary Shelton
Alex Tuyahov
James Yoder
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IV
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TABLE OF CONTENTS
ACKNOWLEDGMENTS II
NOTICE II
THIS REPORT SHOULD BE CITED AS II
FOREWORD I"
WORKSHOP PLANNERS IV
TABLE OF CONTENTS V
LISTOFTABLES "X
EXECUTIVE SUMMARY XI
SECTION 1: INTRODUCTION: WORKSHOP STRUCTURE 1
WATER RESOURCE TYPES CONSIDERED 2
WATERSHEDS, LAKES AND RIVERS 2
WETLANDS 2
GROUNDWATER 3
OCEANS AND ESTUARIES 3
REMOTE SENSING TECHNOLOGIES CONSIDERED 4
ELECTROMAGNETIC SENSORS 4
RADIOMETRIC RESOLUTION 4
SPATIAL RESOLUTION 5
TEMPORAL RESOLUTION 5
SECTION 2: GENERAL FINDINGS AND RECOMMENDATIONS 7
TECHNICAL APPLICATIONS WITH POTENTIAL FOR EPA/NASA PARTNERSHIP 8
NON-POINT SOURCE POTENTIAL FROM LAND COVER / LAND USE 8
FLOODING AND WATERBODY EXTENT 8
MODELING RUNOFF, DETENTION TIME, AND FLOW 9
INTEGRATION OF IN SITU AND REMOTELY SENSED MEASUREMENTS 10
AQUATIC HABITAT CLASSIFICATION AND HEALTH 10
RIPARIAN AREA CLASSIFICATION AND HEALTH 11
AREAL EXTENT OF IMPERVIOUS SURFACES 12
WATER QUALITY: CLARITY AND COLOR 12
WATER SURFACE TEMPERATURE 13
TEMPORAL PROFILING OF VEGETATION GREENNESS 14
SECTION 3 : EPA MONITORING NEEDS, NASA MONITORING TECHNOLOGIES 15
A NATURAL PARTNERSHIP: EPA & NASA MISSIONS 15
EPA'S WATER MONITORING MISSION TUTORIAL 16
THE WHITE PAPER 17
DETERMINING MONITORING PROGRAMS' NEEDS 17
THE CLEAN WATER ACT AND MONITORING: AN OVERVIEW 18
How AND WHY MONITORING FALLS SHORT 21
NEW DIRECTIONS IN EPA WATER MONITORING 23
DISCUSSION AND RECOMMENDATIONS FOR IMPROVING WATER RESOURCES MONITORING THROUGH USE
OF ADVANCED TECHNOLOGIES 26
REFERENCES 27
NOTICE 27
NASA'S REMOTE SENSING MISSION TUTORIAL 28
TUTORIAL PRESENTATION 28
EARTH SCIENCE ENTERPRISE COMPONENTS 30
SECTION 4: WORKSHOP FINDINGS 31
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BREAKOUT SESSIONS 31
WATERSHEDS, RIVERS AND LAKES 32
INTRODUCTION TO WATERSHEDS, RIVERS AND LAKES MONITORING 32
BREAKOUT SESSION FINDINGS 32
PRECIPITATION ANALYSIS 33
NEEDS AND APPLICABLE TECHNOLOGIES 33
GAPS IN CURRENT TECHNOLOGIES 34
EMERGING TECHNOLOGIES 34
SNOW COVER AND PACK DEPTH 34
NEEDS AND APPLICABLE TECHNOLOGIES . : 34
GAPS IN CURRENT TECHNOLOGIES 35
EMERGING TECHNOLOGIES 35
EVAPOTRANSPIRATION FROM LAND AND PLANTS 35
NEEDS AND APPLICABLE TECHNOLOGIES 35
GAPS IN CURRENT TECHNOLOGIES 36
EMERGING TECHNOLOGIES 36
WATER QUANTITY: RUNOFF, FLOODING AND WATERBODY EXTENT 36
NEEDS AND APPLICABLE TECHNOLOGIES 36
GAPS IN CURRENT TECHNOLOGIES . 37
EMERGING TECHNOLOGIES 37
WATER QUALITY 38
NEEDS AND CURRENT TECHNOLOGIES 38
GAPS IN CURRENT TECHNOLOGIES 39
EMERGING TECHNOLOGIES 39
SOIL MOISTURE 39
NEEDS AND CURRENT TECHNOLOGIES 39
GAPS IN CURRENT TECHNOLOGIES 40
EMERGING TECHNOLOGIES 40
LAND USE / LAND COVER 40
NEEDS AND CURRENT TECHNOLOGIES 40
GAPS IN CURRENT TECHNOLOGIES 41
EMERGING TECHNOLOGIES 41
TOPOGRAPHY AND TERRAIN ANALYSIS 42
NEEDS AND CURRENT TECHNOLOGIES 42
GAPS IN CURRENT TECHNOLOGIES 42
EMERGING TECHNOLOGIES 43
WETLANDS 44
INTRODUCTION TO WETLANDS MONITORING 44
BREAKOUT SESSION FINDINGS 45
WETLANDS MAPPING, INVENTORY AND BOUNDARY DELINEATION 45
NEEDS AND APPLICABLE TECHNOLOGIES 45
GAPS IN THE CURRENT TECHNOLOGIES 46
EMERGING TECHNOLOGIES 46
CHANGE ANALYSIS OF WETLAND EXTENT 47
NEEDS AND APPLICABLE TECHNOLOGIES 47
GAPS IN THE CURRENT TECHNOLOGIES 47
EMERGING TECHNOLOGIES 48
NUISANCE SPECIES AND EDGE EFFECTS 48
NEEDS AND APPLICABLE TECHNOLOGIES 48
GAPS IN THE CURRENT TECHNOLOGIES 48
EMERGING TECHNOLOGIES 48
STRUCTURAL AND FUNCTIONAL ASSESSMENT AND TREND ANALYSIS 49
VI
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NEEDS AND APPLICABLE TECHNOLOGIES 49
GAPS IN THE CURRENT TECHNOLOGIES ... 49
EMERGING TECHNOLOGIES 49
INUNDATION AND SOIL MOISTURE IN SATURATED WETLANDS 50
NEEDS AND APPLICABLE TECHNOLOGIES 50
GAPS IN THE CURRENT TECHNOLOGIES 50
EMERGING TECHNOLOGIES 50
SALINITY IN SOIL AND WATER 51
NEEDS AND APPLICABLE TECHNOLOGIES 51
GAPS IN THE CURRENT TECHNOLOGIES - - 51
EMERGING TECHNOLOGIES 51
GROUNDWATER 52
INTRODUCTION TO GROUNDWATER MONITORING 52
BREAKOUT SESSION FINDINGS 53
AQUIFER DELINEATION 53
NEEDS AND APPLICABLE TECHNOLOGIES 53
GAPS IN CURRENT TECHNOLOGIES 54
EMERGING TECHNOLOGIES 54
AQUIFER CHANGE DETECTION 54
NEEDS AND APPLICABLE TECHNOLOGIES 54
GAPS IN THE CURRENT TECHNOLOGIES 54
EMERGING TECHNOLOGIES 54
DETERMINATION OF RECHARGE AND DISCHARGE ZONES 55
NEEDS AND APPLICABLE TECHNOLOGIES 55
GAPS IN THE CURRENT TECHNOLOGIES 55
EMERGING TECHNOLOGIES 55
ACID MINE DRAINAGE DELINEATION 56
NEEDS AND APPLICABLE TECHNOLOGIES 56
GAPS IN THE CURRENT TECHNOLOGIES 56
EMERGING TECHNOLOGIES 56
SALINITY MAPPING 57
NEEDS AND APPLICABLE TECHNOLOGIES , 57
GAPS IN THE CURRENT TECHNOLOGIES 57
EMERGING TECHNOLOGIES 57
GROUNDWATER SUBSIDENCE 57
NEEDS AND APPLICABLE TECHNOLOGIES 57
GAPS IN THE CURRENT TECHNOLOGIES 57
EMERGING TECHNOLOGIES 58
DETECTION OF POTENTIOMETRIC SURFACE 58
NEEDS AND APPLICABLE TECHNOLOGIES 58
GAPS IN THE CURRENT TECHNOLOGIES 58
EMERGING TECHNOLOGIES 58
OTHER GROUNDWATER MONITORING NEEDS 58
ESTUARIES AND OCEANS 61
INTRODUCTION TO ESTUARIES AND OCEANS MONITORING 61
BREAKOUT SESSION FINDINGS 61
WATERSHED IMPACTS ON ESTUARY WATER QUALITY 62
NEEDS AND APPLICABLE TECHNOLOGIES 62
GAPS IN THE CURRENT TECHNOLOGIES 62
EMERGING TECHNOLOGIES .. 62
LARGE ESTUARIES AND COASTAL WATERS 63
NEEDS AND APPLICABLE TECHNOLOGIES 63
VII
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GAPS IN THE CURRENT TECHNOLOGIES 63
EMERGING TECHNOLOGIES 63
TURBID COASTAL WATERS 63
NEEDS AND APPLICABLE TECHNOLOGIES 63
GAPS IN THE CURRENT TECHNOLOGIES 64
EMERGING TECHNOLOGIES 64
OCEAN AND ESTUARIES - GENERAL PROGRAM 64
NEEDS AND APPLICABLE TECHNOLOGIES 64
GAPS IN THE CURRENT TECHNOLOGIES 65
EMERGING TECHNOLOGIES 65
APPENDIX A 67
APPENDIX B 69
REMOTE SENSING DATA SOURCES AND INFORMATION 69
EARTH OBSERVATION SATELLITES: PAST 69
EARTH OBSERVATION SATELLITES: CURRENT 71
EARTH OBSERVATION SATELLITES: FUTURE 74
APPENDIX C 79
EPA/NASA WORKSHOP ON WATER MONITORING, REMOTE SENSING, AND ADVANCED
TECHNOLOGIES ATTENDANCE LIST 79
APPENDIX D 87
COMMENTS ON MONITORING NEEDS FROM ERA'S REGIONAL OFFICES: 87
ANSWERS TO THE FOUR MAIN QUESTIONS: , 87
1. WHAT ARE THE MOST PROMINENT WATER QUALITY PROBLEMS IN YOUR AREA AND IN WHAT KIND OF
WATER BODIES ARE THEY OCCURRING? 87
2. WHICH OF THESE ARE NOT WELL MONITORED AND WHY? 90
3. IF YOU COULD REINVENT WATER MONITORING,
WHATWOULDYOU IDEALLY LIKE TO BEABLETO MEASURE? 92
4. WHAT ARE YOUR IDEAS OF "CONDITION" IN WATERSHEDS AND WATER BODIES, AND HOW WOULD YOU
MEASURE THIS? 93
OTHER GENERAL ANSWERS AND RECOMMENDATIONS: 94
APPENDIX E 99
ACRONYMS 99
viii
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LIST OF TABLES
TABLE 1.1: SUMMARY OF PARTICIPATING AGENCIES AND INSTITUTIONS 1
TABLE 2.1: COMMON THEMES IN RESEARCH FINDINGS AND RECOMMENDATIONS 7
TABLE 3.1: PARTICULARLY USEFUL ATTRIBUTES FOR
REMOTELY SENSED WATER RESOURCES MONITORING DATA 15
TABLE 3.2: RELATIVE PROPORTIONS OF
SURVEYED WATER BODIES MEETING DESIGNATED USES, 1996 20
TABLE 3.3: MONITORING SHORTCOMINGS, MONITORING NEEDS,
AND TECHNOLOGIES THAT MAY IMPROVE MONITORING 23
TABLE 3.4: LIST OF INDICATORS USED IN THE INDEX OF WATERSHED INDICATORS (IWI) 24
TABLE 3.5: FOUR KEY NASA EARTH SCIENCE ENTERPRISE MISSIONS 30
TABLE 4.1: MONITORING NEEDS FOR NEAR-SURFACE MEASUREMENTS 59
TABLE 4.2: MONITORING NEEDS FOR BELOW-SURFACE MEASUREMENTS 60
IX
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EXECUTIVE SUMMARY
The EPA/NASA Workshop on Water Monitoring, Remote Sensing and Advanced
Technologies of December 1996 was held to identify NASA remote sensors and
advanced technologies that could assist EPA and its local and state partners in
monitoring the condition of the nation's water resources. Workshop findings and
recommendations generated by EPA and NASA personnel are still timely and relevant
today. This workshop report summarizes, with minor updates, the water resources
monitoring applications of remote sensing instruments that were identified during the
1996 workshop.
Prior to attending the workshop, participants were provided a background paper that
outlined the EPA's water resources monitoring mission and identified science areas that
might benefit from remote sensing and advanced technologies. At the workshop, EPA
personnel emphasized agency needs for high spatial and temporal resolution
monitoring instruments that enable national assessment, as well as instruments that
would improve monitoring efficiency and accuracy at local scales. NASA personnel
provided a tutorial to introduce the Earth Science Enterprise mission and other relevant
technologies. Joint EPA and NASA moderators then guided the 74 workshop
participants in breakout session discussions that were organized into four principal
water resource areas: watersheds, rivers, and lakes; wetlands; groundwater; and
estuaries and oceans. Each breakout session identified possible applications of
existing and future remote sensing and advanced technologies to water resources
monitoring needs.
Common themes in the workshop findings included: decentralizing EPA and NASA
interactions with regional offices; increasing training in remote sensing; facilitating
technology transfer; ensuring data standardization and consistency; developing pilot
projects that demonstrate remote sensing applications; and coordinating the
simultaneous collection of in-situ and remotely sensed data. Monitoring areas in which
remote sensing showed the greatest promise included: assessment of non-point source
pollution; determination of flooding and waterbody extent; aquatic habitat classification
and health assessment; riparian habitat classification and health assessment; land use
/ land cover mapping; detection and measurement of suspended sediment,
temperature, and algal blooms; and temporal profiling of vegetation greenness.
The specific recommendations from each breakout session identify the monitoring
needs and applicable technologies, point to gaps in current technologies, and then
conclude by identifying emerging technologies that are under development or in
planning. This report serves both as a reference for identifying current applications of
remote sensing in water resources monitoring and as a guide to better understanding
how such advanced technologies may partner with water resources monitoring
missions.
XI
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XII
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SECTION 1
INTRODUCTION
The EPA /NASA Workshop on Water Monitoring. Remote Sensing and Advanced
Technologies was held on the 11th and 12th of December 1996 in Washington, DC.
U.S. Environmental Protection Agency (EPA) and National Aeronautics and Space
Administration (NASA) employees comprised the majority of workshop participants
(Table 1.1), but a small number of other agencies, states and academic institutions
were also represented. A complete listing of the workshop participants can be found in
Appendix C.
Table 1.1: Summary of Participating Agencies and Institutions.
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EPA/Research
EPA/Water
EPA Regions
EPA Other Offices
NASA
NASA Academic/Investigation
State / Academic
Other Agencies
Total Attendance
13
9
9
3
14
20
2
4
74
Workshop Structure
This workshop was designed jointly by EPA and NASA to initiate inter-agency
discussions on the topic of monitoring water resources with remote sensing and other
advanced technologies. The Workshop Statement of Purpose is provided in the
Foreword, located on page ///of this report.
The workshop took place over the course of two days and was structured to maximize
the time spent on identifying technologically advanced and appropriate approaches to
water resource monitoring. The entire workshop agenda is presented in Appendix A.
Workshop participants were sent a background white paper (see Section 3) that
summarized EPA's Clean Water Act mandate and the shortcomings of current
monitoring programs, and identified how NASA advanced technologies such as remote
sensing might assist EPA in meeting their mandate.
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Remotely Monitoring Water Resources
An EPA/NASA Workshop
The first part of the workshop provided tutorials in EPA water resources monitoring
needs and NASA remote sensing instruments, thereby orienting the participants toward
relating the two agencies' activities. The remainder of the workshop was then dedicated
to identifying remote sensing and advanced technologies that might be applied to
EPA's specific water resource monitoring needs. These discussions occurred within
Breakout Sessions that were co-moderated by EPA and NASA scientists.
Water Resource Types Considered
Four separate water resource categories were used to structure discussions on
monitoring needs and potential remote sensing and advanced technology applications.
The four water resource categories included: watersheds, lakes, and rivers;
wetlands; groundwater; and estuaries and oceans. These resources are briefly
described below in terms of their distribution, their volume relative to the global supply
of water, and their residence time (the amount of time necessary for water to move
through the water body of interest), which are all factors that influence the utility of
monitoring with remote sensing or other advanced technologies.
Watersheds, Lakes and Rivers
Water bodies in this category - lakes, rivers and streams - are the principal inland
surface water bodies; watersheds are their surrounding drainage areas. Rivers (taken
to mean all rivers and streams of any size in this workshop) contain approximately 0.2
% of all available fresh water resources; there are over 3 million miles of rivers and
streams in the US. Lakes and reservoirs, which are usually grouped in the same
category, contain approximately 3.0 % of available fresh water resources. Residence
times are highly variable according to water body size. About 40 % of these freshwater
bodies do not fully meet state water quality standards.
Watersheds, which encompass the land area and subsurface aquifers draining into a
body of water, often also include groundwater, soil moisture, biospheric water, and
atmospheric water that contribute to the rivers and lakes. In some areas, and during
some seasons, snow and glaciers contribute additional sources of water. Soil contains
approximately 1.7 % of available fresh water, which has a residence time of 2 weeks to
1 year. Atmospheric water is approximately 0.2 % of all fresh water and has a residence
time of 1.3 weeks. Watershed characteristics such as soils, surficial geology, and land
use/land cover, and processes such as runoff quality and quantity and pollutant
transport, groundwater recharge, and erosion/deposition of sediment, often affect the
quality and quantity of lake and river water resources.
Wetlands
Wetlands are a diverse group of surface water resources that are typically found at the
interfaces of terrestrial and aquatic ecosystems. They are defined and delineated by the
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Remotely Monitoring Water Resources
An EPA/NASA Workshop
presence of characteristic saturated soil types and water tolerant plant species, and
distinct periods of near-surface saturation or surface inundation. Wetlands are often
attributed with beneficial functions such as stream flow moderation (including flood
control as well as base flow maintenance during drought), shoreline stabilization,
sediment trapping and nutrient retention, and wildlife habitat. Wetlands comprise
approximately 6 % of the earth's total land area; over half of the wetland area in the US
has been lost since colonial times, concurrent with an undetermined amount of
degradation or loss of beneficial wetland functions.
Groundwater
Groundwater resources are subsurface water reserves that are held in saturated soils
and geologic formations. Groundwater reserves interact with unsaturated soils,
wetlands, rivers, and lakes, and depending on the surface topography or the hydrologic
regime, these interactions can result in a gain or loss of surface waters from place to
place and time to time. Groundwater that is readily retrievable for drinking water
comprises approximately 97% of all freshwater supplies (approximately 9.9 x 106 km3)
and has a residence time that ranges from 2 weeks to 10,000 years. In the United
States, ground water provides 50% of all drinking water (90% in rural areas), 25% of
industrial water and 34% of agricultural irrigation. As human population increases
competition for fresh water, particularly ground water in arid and semi-arid lands, will
likely become more intense. Degradation of groundwater resources is not thoroughly
documented in national monitoring reports, but the monitoring and reporting of ground
water quality is increasing significantly. Impairment of groundwater often occurs from
infiltration of surface contaminants, or migration of pollutants from uncontrolled burial or
landfilling sites. Loss of groundwater is often due to overutilization or reduction in the
ability to recharge aquifers.
Oceans and Estuaries
Near-coastal ocean waters and estuaries are the focus of EPA's coastal programs.
Estuaries are located at the interface of fresh and saline waters, often defined by the
tidally influenced zone at the mouth of a river entering the ocean. Oceans and estuaries
comprise over 97% of all water on the earth and evaporation from these reserves
produces the fresh water which later precipitates over land to recharge rivers, lakes,
wetlands, and groundwater supplies. Residence times vary with size. Burgeoning
coastal populations are creating a greater need for monitoring coastal water quality to
detect emerging water resource problems as early as possible.
*****
These four resource types inevitably have some overlap. Certain characteristics of the
watersheds, lakes and rivers category in particular are held in common with the other
three categories: 1) the fact that virtually all water bodies have watersheds; 2) the
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Remotely Monitoring Water Resources
An EPA/NASA Workshop
surface and subsurface water exchanges among rivers, lakes, wetlands, estuaries,
oceans and groundwater; and 3) the wetland types that are physically similar to or co-
located with lake littoral areas and riparian areas of streams and rivers. Therefore, the
report discusses all watershed implications for all water body types under the
watersheds, lakes and rivers heading, and also identifies areas where monitoring
needs of one category of water resource are transferrable to the other categories.
Remote Sensing Technologies Considered
A host of environmental remote sensing instruments have been developed and
launched into orbit by NASA and other international space agencies since the 1970s.
New and improved technologies are continually developed by these agencies, and due
to legislation signed in the 1990's, private companies are now also developing and
launching environmental sensing technologies into earth's orbit. In this section, several
basic premises common to many remote sensing technologies are introduced.
Materials on the earth's surface, such as water, soil, and plant chlorophyll, have a
unique atomic structure that reflects a predictable and often unique amount of radiation
at each interval along the electromagnetic spectrum. A material's unique reflectance
curve is often referred to as its spectral signature. Electromagnetic radiation, arriving
from the sun or sent by a remote sensor, can range from the very short wavelength
gamma rays and x-rays to the visible and near infrared and onto the longer microwave
and radio. Only certain parts of the electromagnetic spectrum are useful for certain
remote sensing applications. For example, at some wavelengths the material of interest
may not reflect any unique signature, while at other intervals the material may display a
very unique signature but atmospheric gasses might trap the signal and prohibit its
detection by the sensor.
Electromagnetic Sensors
Electromagnetic sensors are not capable of detecting and measuring all spectra, and
instead are designed to measure across a discrete range of the entire electromagnetic
spectrum. Using the physical relations of electromagnetic theory along with extensive
laboratory and field tests scientists have successfully identified the specific spectra or
combinations of spectra most strongly emitted from, and unique to, the environmental
resources of interest (e.g. water, suspended sediment or chlorophyll). Sensors
commonly used in environmental remote sensing include those designed for gamma
radiation, visible radiation, infrared radiation, thermal radiation, and microwave
radiation. Remote sensing instruments are often categorized by the electromagnetic
sensor's radiometric resolution, spatial resolution, and temporal resolution.
Radiometric Resolution
Radiometric resolution refers to the band-size or spectral range of the electromagnetic
sample received by the remote sensor. Many multi-band remote sensing platforms that
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Remotely Monitoring Water Resources
An EPA/NASA Workshop
sample in the visible spectrum are designed to retrieve signals at red, green, and blue
wavelengths, which corresponds to spectral ranges from approximately 0.45 to 0.55 for
red, 0.55 to 0.65 for green, and 0.65 to 0.75 for blue. If a single sensor is used to
sample at this resolution the sensor is considered broad band, while hyper-spectral
sensors are capable of resolving multiple wavelengths within each of these bands.
Spatial Resolution
Spatial resolution refers to the horizontal length scale resolved by each individual
electromagnetic sensor pixel aboard the platform. Remote sensing platforms typically
have a fixed spatial resolution, and current technologies use resolutions that range from
1-m to over 1-km length scales. During data retrieval events remote sensing platforms
will sample an entire scene that is composed of an array of pixel areas, resulting in an
entire ground swath area of 10Os to 10,000s of km2 at the same point in time.
Temporal Resolution
Temporal resolution refers to the frequency at which the remote sensing platform
revisits the same point in space. Geostationary remote sensing platforms are in high
orbits (10,000s of km) that position them above the same general area and can
therefore retrieve duplicate images at sub-hourly temporal resolutions. Sun-
synchronous platforms are in lower (600 to 1000 km), semi-polar, orbits that typically
result in temporal resolutions measured in the 10's of days after the platform has circled
the entire earth. More advanced sun-synchronous platforms are sometimes designed
with tilting sensors that allow the platform to retrieve duplicate coverage by using a
different 'look' angle. These platforms can achieve temporal resolutions that are hourly
to daily.
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Remotely Monitoring Water Resources
An EPA/NASA Workshop
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SECTION 2
GENERAL FINDINGS AND RECOMMENDATIONS
General findings and recommendations identified by the participants of the EPA/NASA
Workshop on Water Monitoring, Remote Sensing, and Advanced Technologies are
presented in this section. Although the workshop utilized four water resource types to
organize the discussion of which NASA remote sensing instruments might assist EPA in
performing monitoring needs, this section presents findings that were major and/or
common across all water resource types. Table 2.1 provides a summary of the general
findings and recommendations of the workshop participants. Then, several technical
applications areas with potential for collaboration among EPA and NASA are
discussed.
Table 2.1. Common Themes in Research Findings and Recommendations.
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resolution remote sensing makes available.
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Ensure that all remotely sensed data are measured dependably by creating data
standards. Increase the amount of raw data that can be processed or used in
environmental modeling or monitoring applications by developing data consistency
standards.
V
A*
,^2SC^S&-ซs'1^^'"-^i EtJSfciซMMa6a*WHaMSHsซia^^ rTTIur^ti,.,,*-
Coordinate remotely sensed data collection with in situ data collection to authenticate
classification procedures and develop new empirical relationships.
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Remotely Monitoring Water Resources
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Technical Applications with Potential for EPA/NASA Partnership
Workshop participants also identified science initiatives that could be implemented into
existing EPA and NASA monitoring and remote sensing programs. These workshop
findings are described according to their action type (institutional, application, or
general), status (operational or developmental), and applicability (mainly what types
of water resources it applies to).
NON-POINT SOURCE POTENTIAL FROM LAND COVER / LAND USE
At a range of spatial scales, classification levels, and spatial resolutions, land use can
be identified as having the potential to be a cause or an origin of non-point source
(NPS) pollution loading. The linking of land use type with pollution loading potential is
frequently applied but always ready for improved technical assessment methods and
wider, more consistent application. One relatively simple NPS prediction model is the
Export Coefficient Model that uses area! estimates of land cover class types together
with empirically derived nutrient export coefficients from those land classes to estimate
total basin NPS pollution loading at annual time steps. This model can be
parameterized using a single input of land cover / land use from multi-spectral sensors
(MSS) in the visible and near-infrared wavelength. More recent studies have coupled
continuous distributions of terrain elevation with land cover classes to rank the
watershed areas with the greatest NPS loading potential. These studies used remotely
sensed terrain data to compute the upslope contributing area and downslope dispersal
area for each land area and then ranked the likelihood that a critical amount of runoff
both entered that land parcel and traveled from the land parcel to the adjacent
waterbody.
Action type: Application
Status: Operational
Applicability: All watersheds and waterbodies
FLOODING AND WATERBODY EXTENT
One of the most operational uses of remote sensing is detection of flooding and
waterbody extent. The water-land interface is critical information for determining human
health and safety risks, assessing threats to water quality, and estimating the extent
and volume of water resources. The detection of these interfaces is limited by sensor
resolution and sensor response functions. Generally, airborne sensors are used when
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the timing of data retrieval is critical or high spatial resolution is required (usually over
limited areas), while spaceborne sensors provide more frequent although coarser
monitoring options. Appropriate sensors include MSS of visible and thermal
wavelengths as well as microwave radar sensors for overcast conditions. High-
resolution satellite sensors can resolve lakes and ponds greater than 1 ha in area (e.g.
30-m length scales), while coarser scale 1-km sensors can create large boundary errors
in detecting waterbody boundaries.
Action Type: Application
Status: Operational
Applicability: Streams, lakes, wetlands, watersheds, estuaries
MODELING RUNOFF, DETENTION TIME, AND FLOW
Land surface characteristics influence runoff, infiltration, detention time, and resultant
in-stream flow dynamics. Runoff quantity, as a result, is a critical parameter affecting
dilution of pollutants and directly linked to the risk of poor water quality conditions.
Remote sensing of parameters linked to effects on runoff and flow can feed an entire
family of watershed-based models that are useful in predicting water quality and
quantity. Improved accuracy and availability of remotely sensed data that parameterize
runoff models would be extremely useful across all spatial scales. A recent need for
these spatially distributed data sets is in Total Maximum Daily Load- (TMDL) related
watershed modeling. TMDL-related modeling attempts to estimate the relative
contributions of all point and non-point sources of a given pollutant in the watershed, in
planning for reducing their total loads to ensure that a water quality standard is met.
Some watershed models may ultimately require daily time step data inputs at
resolutions that capture NFS pollution loading processes. Model input data types might
include land cover classes, leaf area index and associated evapotranspiration indices,
impervious surface mapping, and various topographical parameters such as drainage
networks, estimates of runoff contributing areas, and pollutant transport dispersal
areas.
Action Type: Application
Status: Operational to Near Operational (varies)
Applicability. All types of watershed and waterbodies
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INTEGRATION OF IN SITU AND REMOTELY SENSED
MEASUREMENTS
Models need both in situ and remotely sensed measurements to achieve accurate
parameterization and produce reliable results. The two data types, in situ and remotely
sensed, represent mutually supporting data points that can synergistically operate to
both reduce costs and increase reliability of the derived information. Models that utilize
remote sensing data to test hypothesis regarding watershed processes can provide a
priori information to guide the placement of in situ monitoring stations and indicate
whether the data are representative. While the coupling of in situ and remotely sensed
measurements has traditionally occurred during calibration and validation of remote
sensing instruments, a continued coordination of the two activities is necessary to
ensure accuracy during the entire lifetime of the equipment. Furthermore, the
coordination of the two sampling techniques allows for a spatial extension or scaling of
the in situ data across the domain of the remotely sensed data. An example of this
coordinated sampling is seen in the combined use of rain gauges with radar microwave
precipitation analysis, where the radar provides comprehensive spatial coverage and
the rain gauges indicate measurement bias and error.
Action Type:
Institutional - create multi-disciplinary science working groups;
General: EPA works frequently at the 8-digit Hydrologic Unit Code (HUC)
basin scale, but many monitoring activities span local- to national-scale
issues;
- Application: Focus on non-point source & watershed levels - local to
national.
Status: Operational for some non-point and watershed levels
Applicability: All areas
AQUATIC HABITAT CLASSIFICATION AND HEALTH
EPA's watershed programs have a fundamental need for general indicators of aquatic
and terrestrial habitat condition and classification. Habitat can be assumed here to
mean aquatic habitats, riparian habitats, and upland habitats through the watershed.
Water resources management relies upon timely and spatially representative sampling
of habitat to guide management decisions. Many of the indicators currently used are
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limited to in situ monitoring, however remote sensing can provide rapid and spatially
extensive estimates of land cover biomass, vegetation class, and some types of habitat
change, as well as measurements of aquatic temperature, chlorophyll concentrations,
and sediment load for larger bodies of water. No single indicator or index will serve to
represent all aspects of aquatic ecosystem health, however a variety of indicators
sampled from visible, near infrared, and thermal sensors, together with microwave
radar sensors, are capable of measuring components of habitat class and health.
Research that develops relations between habitat and remotely sensed parameters is
in need of continued funding. Developing and utilizing habitat indicators is a high
priority need for EPA's Index of Watershed Indicators (IWI) and other projects. A team
from both agencies might be able to offer assistance in the development of such
indicators and how to measure them from imagery and ancillary data on the 8-digit HUC
watershed scale.
Action Type: Application
Status: Research to Near-Operational
Applicability: All waterbodies and watersheds
RIPARIAN AREA CLASSIFICATION AND HEALTH
Riparian areas are the buffers joining the aquatic ecosystem with the adjacent terrestrial
ecosystem, and are periodically likely to experience various stages of saturation or
flooding. In many areas, riparian zones have been cleared of natural cover and
replaced with crops or lawns, left as bare earth, or converted to impervious surfaces
and development. Intact riparian areas that have vegetative cover may provide
numerous beneficial functions for people as well as aquatic and terrestrial
environments. For terrestrial ecosystems, these riparian areas mitigate the impact of
overbank flooding and erosion, and for the aquatic ecosystem the buffer areas provide
organic matter, shade, and 'buffering' capacity against surface and subsurface
pollutants travelling from toward the stream. Remote sensing instruments that operate
at high spatial resolutions are capable of detecting riparian buffer presence or absence
but are unable to detect micro-topographic or vegetative features that may strongly
influence the ability of the area to filter suspended pollutants. Desirable riparian zone
widths are related to stream size, so spatial resolution requirements vary with stream
size, from 1-m sensors zones along smaller perennial streams to 30-m resolution
sensors along larger rivers. Measurements relating to riparian zone structure, integrity,
and contiguity would be useful nationally or regionally, however most assessments of
riparian zone structure or condition have only been done in scattered locations. A
national indicator of riparian zone condition would have immense value if able to be
applied on 8-digit Hydrologic Unit Code (HUC) watersheds.
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Action Type: Application
Status:
Operational at the local scale;
Near-Operational at regional to national scales.
Applicability. Watersheds, lakes, rivers, streams, wetlands, estuaries
AREAL EXTENT OF IMPERVIOUS SURFACES
Urbanization traditionally replaces a significant percentage of a watershed's soil surface
and vegetation with concrete, rooftops and altered drainage systems. These changes to
the landscape result in a change in the speed, volume and quality of infiltration and
runoff, sometimes significantly altering streamflow volume, flooding frequency, and
water quality. Information on the extent of impervious cover for various parts of the
watershed is extremely valuable for identifying and ranking NFS problems, modeling
storm flow dynamics, siting detention basins, and developing watershed management
remedies. Some indexes of impervious area have been developed for different
densities of residential development and urban downtown environments. Remote
sensors of visible and near infrared can distinguish between impervious non-impervious
areas and thereby help managers estimate the watershed response to precipitation
events. Although remote sensing instruments can assist in estimating the percentage of
precipitation that does not infiltrate, the technologies are currently unable to provide
estimates of the complex urban drainage networks of street drains and culverts. The
use of Geographical Information Systems (CIS) is recommended to integrate in situ and
remotely sensed measurements as input into runoff prediction models.
Action Type: Application
Status: Operational (local and regional scale) and Research
Applicability. Watershed
WATER QUALITY: CLARITY AND COLOR
In situ measurement of water quality parameters such as clarity and color are relatively
straight forward and represent the water properties such as chlorophyll, total
suspended solids (TSS), total organic phosphorous, specific conductance, dissolved
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organic carbon (DOC), selected minerals, and water pH. Remote sensing of water
clarity and color is feasible with visible and near infrared sensors, but the sensor
measurements must be calibrated with in situ measurements. Required field
measurements should contain representative sampling of the range of conditions
typically present within a resource and throughout a given monitoring period. For
deeper waters the remote sensing instruments are limited to the upper water column
due to the rapid adsorption and scattering of visible light by water. Detection of clarity
and color is performed best on water bodies that that exceed the spatial resolution of
the sensor by a factor of 10 (e.g. 1.25-ha per 30 m Landsat pixel). Operational
instruments include MSS on aircraft (resolution 1 to 20-m) and satellites (resolution 30-
m to 1-km) and non-imaging airborne laser fluorosensors. Available experimental
instruments include airborne hyperspectral with experimental satellite hyperspectral
instruments being available within 2 years. It is recommended that techniques are
developed to use Secchi measurement for rough calibration of sensor clarity
measurements.
Action Type: Institutional - requires coordination between field crews (remote
and local) for overflights and calibration. Requires moderately sophisticated
equipment and expert knowledge of water variables over the survey area to
interpret results.
Status:
Operational at a regional scale for MSS - limited by available satellite
overflights and cloud cover;
Near-Operational (3 to 5 years) for Hyperspectral applications at the local
level;
Near-Operational for laser fluorosensor at the local level;
Theoretical status for combination of fluorosensor under-flights with
satellite overpass to reduce field sampling required.
Applicability. Lakes, rivers and estuaries
WATER SURFACE TEMPERATURE
Currently EPA is collecting in situ temperature measurements via ground truth and
automatic gauges in numerous streams, rivers, and lakes. Remote sensing instruments
have also been used. For example, NASA, EPA (at Las Vegas, Nevada), other
government agencies, and certain commercial industries have performed thermal
surveys on local, regional and national scales. Helicopter, fixed wing (low and high
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altitude) aircraft and satellites have each been used to retrieve these thermal
measurements and there exists a range of spatial resolutions for the various thermal
sensors. Helicopter and low altitude aircraft provide 1 to 3-m resolution data, small jets
provide 3 to 10-m resolution data, high altitude planes (e.g., the ER-2) provide 20-m
resolution data, and satellites (e.g. Advanced Spaceborne Thermal Emission and
Reflection Radiometer (ASTER) and Landsat 5 and 7) can provide 60 to 120-m
resolution data of thermal aquatic condition.
Action Type: Applications - need national standard
Status:
Operational locally via aircraft for 0.2ฐ C measurements; operational
regionally via satellite on larger bodies of water at 1.0ฐ C;
Near-operational satellites (e.g. ASTER) will improve to 90-m resolution at
0.5ฐ C resolution.
Applicability: Streams and rivers
TEMPORAL PROFILING OF VEGETATION GREENNESS
Vegetation biomass and leaf area indices (LAI) are useful parameters for determining
some aspects of watershed health, stressors and water resource condition. Tracking
the changes in vegetation along time is also critical for drawing associations between
changes in water resource condition and changes in watershed condition.
Combinations of visible and near infrared remote sensing measurements are used to
estimate vegetation health. One popular indicator of LAI and biomass is the normalized
difference vegetation index (NDVI), which is calculated from a variety of sensors,
including the Landsat MSS and Advanced Very High Resolution Radiometer (AVHRR)
satellite imagery. Repeated NDVI analyses, like the biweekly NDVI maps produced
since 1990 by the U.S. Geological Survey (USGS), make it possible to track seasonal
greenness changes and comparisons year to year. Analysis could reveal wet to dry
year differences and significant land cover changes (e.g. fire, harvest, development and
disease). When NDVI data sets are regularly created at national scales then it
becomes possible to separate anomalous seasonal or annual fluctuations from more
significant trends in the composition and vigor of watershed vegetation.
Action Type: Application
Status: Operational to Near-Operational
Applicability: Watershed
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SECTIONS
BACKGROUND: EPA MONITORING NEEDS, NASA
MONITORING TECHNOLOGIES
A Natural Partnership: EPA & NASA Missions
The individual EPA and NASA science missions share common themes and contain
research components that may be addressed by pooling skills and resources from the
two agencies. Just as EPA is mandated to work with states, tribes and others to monitor
and protect the nation's water resources, NASA is mandated to develop and test
environmental remote sensing instruments. The coupling of these science missions
provides EPA and its partners with technologically advanced tools to monitor water
resources and provides NASA with an application that tests remote sensing capabilities
and provides in situ calibration and validation measurements.
Managing the nation's water resources requires that the EPA and the states maintain
strong monitoring programs. Monitoring, with both in situ and remote sensing
technology, provides the agency with useful data for tracking resource status and
trends. Monitoring data that enable EPA and its partners to develop appropriate water
resources management strategies include information that illuminates associative
relationships between water resource condition and anthropogenic or natural stressors.
Not only should monitoring include some information that is consistent at the national
scale and includes stressor as well as response data, but there must also be data at
spatial and temporal resolutions that capture the impairment processes. In summary,
the nation's water resources monitoring programs especially need data with any of the
attributes listed in Table 3.1.
Table 3.1. Particularly Useful Attributes for Remotely Sensed Water Resources
Monitoring Data.
High spatial resolution
Representative of ecosystem condition, stressors
and responses
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EPA's WATER MONITORING MISSION TUTORIAL
Prior to attending the December, 1996 EPA/NASA Workshop on Water Monitoring,
Remote Sensing, and Advanced Technologies, participants were sent the paper,
Needed Improvements in Aquatic Ecosystem Monitoring Methods: A Discussion
Paper for the EPA/NASA Workshop on Water Monitoring and Advanced
Technologies. This white paper presented an outline of the nation's efforts to monitor
water resources puirsuant to the federal Clean Water Act and then identified the
shortcomings in monitoring technologies that limit monitoring capabilities. At the
EPA/NASA Workshop, Elizabeth Fellows and Douglas Norton of the EPA Office of
Water provided a Water Monitoring Mission Tutorial that summarized the White Paper
contents in two short presentations (see Appendix A for the Workshop Agenda).
Rather than summarize the EPA Tutorial, a full and updated copy of the White Paper is
provided in the pages below.
1999 Editor's Note: The following document was written and circulated to all
participants during November 1996 in advance of the workshop. It served as a problem
statement describing the challenges faced in water resources monitoring programs by
EPA and its partners from state, tribal and local water programs. This paper set the
scene for the workshop and enabled NASA and its research community to prepare for
the dialogue on using advanced technologies to help meet these water resources
monitoring and management needs. Minor changes have been made to reflect
program name changes and revised national statistics.
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Needed Improvements in Aquatic Ecosystem Monitoring Methods: A Discussion
Paper for the EPA/NASA Workshop on Water Monitoring and Advanced
Technologies, December 11-12,1996, Washington, DC.
Douglas J. Norton
USEPA Office of Water
Monitoring the condition of our environment is essential to its proper stewardship and
management. States and other jurisdictions have water resources monitoring
programs, but most of these are unable to monitor all of their watersheds, water bodies,
and point- and non-point pollution sources. In reality, the majority of U.S. water bodies
are not monitored regularly and even more are not monitored as well as resource
managers would like. This is both a financial and technical problem, as many
monitoring methods are not suitably cost-effective or efficient for characterizing water
resources condition in a meaningful time frame across all water bodies of interest.
The rapid advancement of new technologies such as remote sensing may some day
provide methods for monitoring more water quality parameters, in more water bodies,
with improved accuracy, or with reduced per-unit costs. To actively improve the status
of monitoring science, however, monitoring professionals must learn about emerging
technologies or those available now, and researchers who develop these technologies
must learn the needs of their clientele. In order to focus and accelerate research and
applications of advanced technologies in monitoring, the U. S. Environmental Protection
Agency (EPA) and the National Aeronautics and Space Administration (NASA) are
convening a workshop to discuss and match monitoring needs with the appropriate
advanced technologies.
This paper provides summary background information for workshop participants about
water monitoring responsibilities and information needs, in order to help NASA
participants understand where and how their technologies may be useful. The paper
covers relevant water law and monitoring programs, their unique challenges and
common water quality problems, and some of the types of solutions that advanced
technologies may offer. Also provided are summarized monitoring needs and
recommendations.
Determining Monitoring Programs' Needs
In developing this paper, we contacted several EPA regional and state monitoring
program staff and managers to gain insight into some of the specific problems they
encounter with monitoring, and the ways they'd like to be helped with these problems.
Their insights have provided the structure and the substance of this paper, and are the
basis for our conclusions and recommendations for the workshop.
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Remotely Monitoring Water Resources
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Each monitoring professional was asked the following four questions:
1. what are the most prominent water quality problems in your area and
in what kind of water bodies are they occurring?
2. which of these are not well monitored and why?
3. if you could reinvent water monitoring what would you ideally like to be able
to measure?
4. what are your ideas of "condition" in watersheds and water bodies?
This effort achieved reasonably good national coverage. Monitoring staff from 9 of 10
EPA regions responded, as did personnel from two states and two other federal
agencies.
The Clean Water Act and Monitoring: an Overview
The EPA has a dual mission that includes the protection of both the environment and of
human health and welfare. The Clean Water Act, which is the primary federal statute
related to the protection of aquatic resources, is one of EPA's main statutory
authorities. The stated goal of the Act is, "to restore and maintain the chemical,
physical and biological integrity of the Nation's waters." The ultimate intent of the law is
to attain and maintain a level of aquatic ecosystem integrity that will sustain human
uses and ecosystem functions. Over the years, the Clean Water Act has evolved from
its narrow origins in water pollution control and end-of-the-pipe discharge limits to a
watershed-oriented statute that supports holistic environmental management within
watershed boundaries.
Under the Clean Water Act, EPA administers several different programs dedicated to
maintaining and improving the Nation's waters. The Act is predominantly state-
implemented under federal oversight, with most of the Act's programs and activities
carried out in concert with states, American Indian tribes, other federal agencies, local
governments, private organizations and citizens. The Clean Water Act therefore is not
only among the federal government's most powerful statutory tools for protecting
aquatic systems, but also provides structure for forming multiple governmental and
private partnerships to pursue Clean Water Act goals. One part of this cooperative
structure pertains to water monitoring programs and the use of monitoring data to
generate national reports on water quality.
Section 305(b) of the Clean Water Act requires that states and other jurisdictions submit
water quality assessment reports every 2 years. The National Water Quality
Inventory Report to Congress, often also called the 305(b) Report, characterizes
water quality, describes widespread water quality problems of national significance, and
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An EPA/NASA Workshop
describes various programs implemented to restore and protect U.S. waters. The
305(b) Report summarizes the monitoring information submitted by states, territories,
tribes and other jurisdictions, and as such it reflects their water quality issues and
concerns, not just those of EPA. The states and others survey their waters by
determining if their waters attain the water quality standards they established. Water
quality standards consist of beneficial uses, numeric and narrative criteria for supporting
each use, and an antidegradation provision. Their reporting summarizes monitoring
results in terms of relative levels of beneficial use support; readers are referred to The
Quality of Our Nation's Water: 1996 (USEPA 1998) for a more detailed discussion of
the 305(b) program and summary monitoring results aggregated by jurisdiction and by
water body type.
The Clean Water Act allows states and others to set their own standards but requires
that all beneficial uses and their criteria comply with the goals of the Act. At a minimum,
beneficial uses must provide for "the protection and propagation offish, shellfish and
wildlife" and provide for "recreation in and on the water" (i.e., the fishable and
swimmable goals of the Act), where attainable. The Act prohibits designating waste
transport or waste assimilation as a beneficial use, as some states did prior to 1972.
The most common form of monitoring in support of the Clean Water Act is water quality
monitoring, defined by the Interagency Task Force on Monitoring as "an integrated
activity for evaluating the physical, chemical, and biological characteristics of water in
relation to human health, ecological conditions, and designated water uses." It consists
of data collection and sample analysis performed using accepted protocols and quality
control procedures, and also includes subsequent analysis of the body of data to
support decision making. A variety of jurisdictions, industries and private groups
monitor a combination of chemical, physical and biological parameters throughout the
country:
Chemical data measure concentrations of pollutants and other chemical
conditions that influence aquatic life, such as pH or dissolved oxygen. Chemical
parameters may be analyzed in water samples, fish tissue samples, or sediment
samples.
Physical data include measurements of temperature, turbidity, and solids in
the water column.
Biological data measure the health of aquatic communities, and include
counts of aquatic species that indicate healthy conditions.
Habitat and other ancillary data help interpret the above monitoring data.
Monitoring agencies and groups vary the parameters, sampling frequency, and
sampling site selection to meet program objectives and funding constraints. Sampling
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An EPA/NASA Workshop
may occur at regular or irregular intervals or in one-time surveys. It is important to note
that states and other jurisdictions do not use identical methods because they favor
flexibility to accommodate variability among their waters, and therefore data are of
limited consistency or comparability.
Data gathered during 1994 and 1995 were compiled to generate the 1996 305(b)
report. Summary figures are presented in Table 3.2 below.
Table 3.2: Relative Proportions of Surveyed Waterbodies Meeting Designated
Uses, 1996 (from USEPA, 1998)
1 Water Body
Type
i
'i< Rivers/
ii
Streams
in
- Lakes,
'" Ponds,
Reservoir
1 s
, Estuaries
::-f ,,
!
Ground -
water (40
ป states"
irep'orflrig1,
limited
data)
Wetlands
(9 states
reporting,
limited
data)
"' v
Total
Surveyed
(%)
19%
40%
72%
X
X
Good -
Fully
Supporting
(%)
56%
'". ''*".' !:::":
51%
58%
'. ." ': >"' J. ซ,n,i;,,i! \ i i
A,,
.;; '
X'"'
' -" i M in, ,ii:i: " -
; Good but
Threatened
"."'- W->'4
8%
10%
4%
X
X
i -; "ImpliresJli
E . ;f6p;C3rwi0r;:|
^'^More'iEtei
i^'^m^m':
36%
39%
38%
X
X
:-ฅ: - .'' :'::;:-:?
^ffcipft&v
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X
III IS
yi-ijV f^^^^-'-'^'^'^^^^'^-^-^^^^^'-'^M^^ *-ฃฃ-:%
'
siltation, nutrients, bacteria,
metals, O2 depletion,
pesticides, habitat
alteration, susp. solids,
metals
nutrients, metals, siltation,
O2 depletion, noxious
aquatic plants, susp. solids,
toxics
nutrients, bacteria, toxics,
O2 depletion, oil & grease,
salinity, habitat alteration
'
nitrates, metals, volatile and
semivolatile organic
compounds
sediment/siltation,
nutrients, filling and
draining, pesticides, flow
alteration, habitat alteration,
salinity /TSS/chlorides,
metals
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Remotely Monitoring Water Resources
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How and Why Monitoring Faffs Short
Well over half of US water bodies are not monitored and assessed in each biennial
305(b) report, and many of the waters that are reported on have less monitoring
data (not enough relevant parameters, too few locations, too infrequent
measurements, or inferior measurement methods) than desirable to be indicative of
ecosystem condition and ambient water quality. The universal reason for this is
that the cost and effort to monitor all waters with conventional methods far
exceeds state and local resources to do so even with federal assistance. Below are
some common shortcomings of water monitoring and the type of technological
solutions that may help to address each problem (see also Table 3.3):
Too infrequent measurements. Some water quality parameters change yearly,
seasonally, daily or even hourly. Elevated temperatures, for example, occur and
do their damage in very brief and irregularly occurring episodes. Infrequent
monitoring can miss episodic impairments or misinterpret direction of water
quality trends. Possible solutions: Continuous recorders may capture the episodic
impairments; remote transponders may be used to signal onset of a condition
needing onsite measurements.
Sampling limitations. Some water quality parameters vary spatially over fairly
short distances. Variability with depth, or with channel morphology (e.g., riffles,
glides, pools, rapids, eddies) can produce different results in, for example,
contaminated sediments. Limited budgets also often result in very few samples
representing tens or hundreds of river miles. The magnitude of problems may be
over- or under-estimated, or missed entirely. Other sampling problems are also
common. Sample locations are often not documented accurately, and samples
may not be timed appropriately to allow adequate evaluation of possible
confounding factors. Possible solutions: greater sample size or the use of
methods that enable synoptic coverage of a water body; more attention to
sampling design; a strong locational data policy requiring GPS use.
Too few parameters measured. Land uses in the watershed often prompt
monitoring programs to test specific water bodies for specific pollutants or
impairments, but there may be other, more subtle problems. Yet blind monitoring
for every possible concern is not feasible. Possible solutions: As direct
measurement of every possible stressor is improbable, the likely solution is to
monitor broadly by using well-chosen indicators associated with groups of water
quality problems, then looking closer on fewer, specific locations of concern.
Data and measurement quality limitations. Limited accuracy or precision of some
monitoring methods and data stands as an obstacle to broader use and limits the
significance of monitoring results. Also, data are often not collected in or
translated into electronic formats that can be easily loaded into fully relational
databases and GIS software. Data are thrown away by agencies because "no
longer needed", rather than given to a central data repository. Possible
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solutions: Methods refinement may improve existing monitoring tools that had
been marginally useful; improved information management and coordination
among programs could reduce waste of older data.
Absence of any monitoring. 83 percent of the total number of perennial rivers
and streams, for example, were not monitored at all in the 2-year 1994 reporting
period. Assuming consistent progress, and given this 2-year reporting cycle and
approximately 1 /6 of the resource monitored per cycle, complete coverage would
take 12 years, change detection 24 years, and the earliest 3-point trend detection
36 years. This is too long to provide meaningful data for management action
based on monitoring insights. Possible solutions: changing the 2-year reporting
cycle for 305(b) to a 5-year cycle, might allow for comprehensive coverage of
state waters over a five-year period. This change, coupled with changes in
monitoring design and the possible uses of synoptic-coverage technologies such
as remote sensing, should bring improvements. To improve cost-per-unit-area,
monitoring programs could employ large-area analysis methods for initial
screening, coordinated data sharing, and better probability-based sampling
designs to stretch the monitoring dollar.
Insufficient analysis of probable causes of impairment. A given water body may
have nutrient problems revealed by monitoring, but no knowledge of the probable
cause of the problem. This is a common concern relative to the more complex
nonpoint source pollution problems. Possible solutions: Accumulate evidence of
and quantify the dose/response relationships evident between stressors in the
watershed and impairments in the water body. Develop new models that
simulate these relationships and strengthen existing model assumptions with
better data.
Insufficient translation into management guidance. Also stemming from the lack
of understanding of probable causes is the inability to step beyond monitoring to
selecting and implementing control measures. Possible solutions: As above,
managers need to draw from a science base of dose/response relationships
between stressors and effects and understanding of thresholds at which impacts
occur, in order to focus management actions on the problem at hand. Models,
ranging in scope from specific dose/response relationships to whole watershed
processes, may help to evaluate the effects of different options for action.
Delays in data availability. The length of time required to analyze monitoring data
is a problem in the case of some common impairments. For example, bacterial
testing requires an incubation period that in effect allows swimmers continued
exposure to pathogens and possible harm while the results of testing are
awaited. Possible solutions: Increasingly, real-time or near-real-time results are
desired. Telemetry provides one option for accessing data that are measured by
in situ sensors and communicated to a manager's computer system remotely via
communications satellite, cellular phone, or even telephone lines. In addition,
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however, more and better in situ or remote sensors are needed to measure more
water quality parameters.
Table 3.3: Monitoring Shortcomings, Monitoring Needs, and Technologies that
may Improve Monitoring.
Too infrequent measurements, sampling limitations, too few parameters measured,
data and measurement quality limitations, absence of any monitoring, insufficient
analysis of probable causes of impairment, insufficient translation into management
guidance, delays in data availability.
Improved temporal coverage, improved spatial coverage, improved accuracy of
measurements, real-time results, lessejq^^ __ __
Improved in-stream/in situ sensors, remote sensing of environment, satellite telemetry
from in situ sensors in water bodies, cellular phone technology from sensors in water
bodies, telephone line hookups to sensors in water bodies, improved modeling used in
conjunction with the above, improved use of indirect (e.g., indicator) vs. direct
measurement, improved laboratory analyses, better computer software for data
management, central data repositories serving local, state and federal programs,
increased use of laptops in the field, improved spatial location data (GPS), increased
training of staff in new monitoring techniques. ,
New Directions in EPA Water Monitoring
In order to draw conclusions about environmental conditions, water monitoring
programs have long been oriented toward measuring single, or sets of closely related
water quality parameters, such as pH, dissolved oxygen, temperature, or concentration
of a given pollutant, at selected locations. These types of measurements will continue
to be essential to water monitoring. In addition to these, however, there is increasing
attention to the concept of the watershed's or water body's overall condition.
Approaches to measuring condition, although still not fully accepted into practice, would
provide the benefits of a big-picture complement to the more narrow and parameter-
specific measurements of traditional monitoring programs.
To begin addressing watershed condition, EPA published a national water indicators
report (USEPA 1996) and characterized the nation's watersheds using many of the key
indicators (USEPA 1997).
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In June 1996, EPA and its cooperators published the report, Environmental Indicators
of Water Quality in the United States. The report's 18 indicators focus on the
condition of the environment and the stressors that impact water resources. EPA
intended to use indicators as the basis of how it measures improvements in water
quality throughout the country. The indicators will be used to measure progress toward
national goals of clean water and safe drinking water, and the objectives of human and
ecosystem health, meeting the designated uses that states set for their waters in their
water quality standards, preserving and improving ambient conditions, and reducing or
preventing pollution loadings and other stressors. They do not measure the
administrative actions taken in response to environmental problems; this is left up to the
management strategies of the involved organizations.
These indicators were refined and published with a geographic basis in a document
entitled the Index of Watershed Indicators in November, 1997. The EPA Office of
Water's Index of Watershed Indicators used indicators to analyze watersheds
throughout the nation based on the 2,150 eight digit Hydrologic Unit Codes
(http://water.usgs.gov/GIS/huc.html), which average approximately 1,700 square miles
in area, to initially characterize condition and vulnerability. The IWI is now entirely
based on the World Wide Web, and has been updated four times since initial
publication. The URL is http://www.epa.gov/IWI/.
A summary of the IWI indicators appears in Table 3.4. The data quality of all of the
indicators is considered variable, but the quality of the data used has been well
documented. These are categorized into indicators of condition and indicators of
vulnerability. A new category of indicators, those showing program responses (e.g., the
type of program and support funding) will be added. Efforts to improve nationally
consistent data sources for key indicators are underway. The category of indicators
describing program responses will be added to the IWI in future updates.
Table 3.4: Summary of indicators used in the Index of Watershed Indicators (IWI).
uses sett
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2). Fish Consumption Advisories - Waters that are subject to State-issued fish consumption
advisories. Advisories issued by States include restricted consumption (generally restrictions
on the number of meals over a period of time or the fish weight consumed over a period of time)
and no consumption offish.
- - '" ' ' - - -- --- -
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: 3), Drinking Water Quality Impacts - Populations served by CWS that are in violation of national
3alth-based drinking water standards for contaminants that are sourcts-related (i.e. inorganic
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6). Wetlands Loss -Wetland loss rates from 1982 to 1992 for individual states; State rate
assigned to cataloguing units (derivedfrom 6-digit accounting unit level). ^^^ T__
*~\ Gon^n|rtat| where moWserious profeJem^ were identifled^iie' t-,
"-"-**'*T>feclaslfflelE'|sTier2, ';,^yf' ... ;:A l";^'/^^ NT.";''*:."""'^ :^^ ^' '
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2). Discharge Loads Above Permitted Discharge Limits - Toxic Pollutants - Loading over the
discharge limits set in each individual NPDES permit for the group of toxic pollutants (e.g.,
mercury, lead, cadmium, and copper) contained in permit limits. Loads for the contaminants will
be combined.
mal Pollutants - ^
t:setintelcli individual NPpJS'^Srm^it for the gro^p; of *oriventioriai^- <
fpolllutentijit|.) ammonia, BOD. nifat>g^si,rphospljOK>us; and suspended solids) contained ~~"-
*_^. ?*ซ_ซ._ ป _JS_jpii ,ป_ *_,... -."____ __ _*_-. -.
4). Non-point Source Impact Potential - Urban Impervious Surfaces - Percent of
imperviousness using established relationships between imperviousness and housing density.
Housing density was aggregated to the block group and assigned to cataloging units.
Information is collected on a probabilistic basis.
5)1 *"Non:poJp|f Source impact Poteflia! - AgrJcalttira,?- fhfe inrflcatoV proV
*lthe4rปreat to tie,c^riiMon of the aquatic system from non-pbint sopjcce pojlujion f rbm -:
6ff1) nitrogef^leahln
6). Population Change - Population growth rate in each watershed. This indicator assigns
scores based on whether population has remained stable or decreased, increased from 0-5%, or
increased more than 5%.
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ation - Stiiam mH dams and other man-made structures.
8). Estuarine Pollution Susceptibility - This indicator uses assessments by NOAA of an
estuary's susceptibility to pollution as defined by its relative ability to concentrate dissolved
and particulate pollutants. An index based on physical, land use, nutrient sources, and nutrient
loading data for all estuaries of the contiguous United States.
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Discussion and Recommendations for Improving Water Resources Monitoring
through Use of Advanced Technologies
Monitoring provides valuable information for environmental stewardship, but as an
applied tool of environmental stewardship it does not yet live up to its potential. In
a time of such rapid technological advancement, we may soon have greater
expectations of technology and of monitoring. Our dialogue with regional and state
monitoring personnel, as well as a number of other current activities that have
investigated ways to improve monitoring, point to many good suggestions to guide
future action:
Cost-effectiveness, or more simply cost, usually drives monitoring programs'
choices of measurement techniques. If a method is too expensive, it will not be
widely used. Funds for monitoring programs are not likely to change even with
availability of improved methods if those methods are costly. On the other hand,
improved speed, low maintenance or large area of coverage can improve the per-
unit cost.
Monitoring programs may achieve better coverage in the future if they focus on
measuring fewer, more meaningful parameters rather than striving to measure every
possible parameter of concern. Long and short term measurement strategies
deserve consideration; long term measurements should cover fewer, more
consistently applied and carefully targeted parameters. Short term measurements
may differ over time, as problems and the state of knowledge change. Choices are
of paramount importance to depict water body condition and the influence of
multiple stressors.
A broad variety of advanced monitoring technologies should be explored to
improve water resources monitoring. This should include not only the full array of
remote sensing technologies available from aircraft or satellite platforms, but also
telemetry using communications satellites, cellular phone technology, and
conventional phone lines. Furthermore, additional methods for real-time in situ
identification, quantification, and temporal and spatial profiling of individual
chemicals in the water column should be explored.
Advances in modeling in conjunction with these technologies should also be
emphasized and fostered using real-life problems in impaired water bodies; there are
so many impaired water bodies available for advanced study that it is difficult to
fathom not using more of these sites for applied research or graduate training. The
most effective basis for such studies would need to include simultaneous
characterization of stressors, exposure pathways, receptors, and effects.
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Matching technologies to monitoring information needs should not be confined to
efforts to use these technologies to measure specific pollutants. Measurements of
ecological responses in the water body, status and changes in the stressors
themselves, and a wide variety of physical, chemical or biological indicators can
also be closely related to environmental health and public welfare. A growing
emphasis on finding measures of watershed and aquatic ecosystem condition and
function, not just conventional measures of common pollutants, is reflected in
many monitoring programs. In addition, cross-media pathways such as airborne
sources of water pollutants remain important.
Chemical and physical measurements continue to be of concern, particularly as
related to point source discharges. A growing interest in biological measures of
watershed and water body condition is now emerging among water resources
managers, and this includes aquatic and shore lands habitat. Successful
development of indicators in these areas would need to be supported by a strong
scientific basis for the selection and interpretation of these indicators as well as by
accurate and precise measurement techniques.
National-scale indicators, despite their desirability as rapid, easy to measure and
widely applicable measurement endpoints, are not magic bullets. Specific and
quantitative physical, biological, and chemical metrics will continue to play a crucial
role in evaluating water and watershed condition for the indefinite future. As such,
water monitoring will continue to need the very specific as well as the very general
environmental measurements.
References
USEPA. 1996. Environmental Indicators of Water Quality in the United States.
EPA841-R-96-002.Office of Water (4503F), USEPA, Washington, DC. 25 pp.
USEPA. 1997. Index of Watershed Indicators. EPA841-R-97-010. Office of Water
(4503F), USEPA, Washington, DC. 56 pp.
USEPA. 1998. The Quality of Our Nation's Water: 1996. Executive Summary of the
National Water Quality Inventory: 1996 Report to Congress. EPA841-R-97-008. Office
of Water (4503F), USEPA, Washington, DC. 521 pp.
Notice
This paper has not been peer or administratively reviewed by the U. S. Environmental
Protection Agency and should not be construed to represent EPA policy. Use of trade
names does not constitute endorsement for use.
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NASA's REMOTE SENSING MISSION TUTORIAL
EPA/NASA Workshop participants were not provided with an equally detailed "White
Paper" on the NASA earth resource science mission. Instead, it was understood that
the NASA earth resource science mission included components that supported the EPA
water resource monitoring needs. NASA's Ghassem Asrar provided workshop
participants a brief sketch of this overlap, in the form of a Remote Sensing Tutorial.
NASA's Tutorial presentation followed upon the EPA Tutorial. NASA's science mission
includes, among other things, the development and testing of advanced technologies
and remote sensing devices for the advancement of earth and environmental science.
1999 Editor's Note: At the time of the conference NASA had named its earth science
mission, "Mission to Planet.Earth". The mission has been renamed is now entitled,
"Earth Science Enterprise" (ESE). A summary of the goals and objectives of the
NASA's ESE Mission is provided in this summary of Ghassem Asrar's Tutorial.
Tutorial Presentation
Mission to Planet Earth: Enabling Earth System Science Research and Education in the
21st Century, December 11, 1996, Washington, DC.
Ghassem Asrar
NASA EOS
During the 1980's ambitious plans were laid out for the beginning of a new era in earth
studies. Presidential Initiatives in the 1990's created the U.S. Global Change Research
Program, including as its largest component, Earth Science Enterprise (ESE), led by
the National Aeronautics and Space Administration (NASA). NASA's Earth Science
Enterprise efforts are aimed at improving our understanding of the earth as a system,
and our ability to assess and predict the environmental, social and economic impacts of
natural and human-influenced processes. The overall goal is to establish the scientific
basis for national and international policy-making in response to changes in the earth
system.
Over the last several decades, an increasing pace of scientific advancement in earth
studies has coincided with increasing public awareness of the global and regional
aspects of environmental issues. Changes in the earth's climate over time have been
documented by evidence from such sources as tree rings, gases trapped in the polar
ice caps, glacial landforms, and stratification in ocean sediments and in rocks. Today,
scientists' track processes of global change, and possibly climate change, in real time.
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The Earth Science Enterprise is primarily focused on obtaining global observations from
spaceborne instruments and to model the earth as a system. As such, attention has
not traditionally focused on the monitoring of water and watershed properties at the
scales used by EPA to assess water resource health. Instead, NASA's integrated,
comprehensive, and sustained Earth Science Enterprise program has documented the
earth system on a global scale that supports focused and exploratory studies of the
physical, chemical, biological, and social processes that influence the earth system.
Despite these apparent discrepancies in spatial scale, the science and technology
develop by NASA's ESE can assist and contribute to EPA's hydrological science
initiatives and water resource monitoring programs.
NASA recognizes that improvements over current capabilities in the range, detail, and
frequency of remote sensing observations are also needed to develop and test
integrated, conceptual and predictive models of the earth. It is the opportunity to work
with EPA in the monitoring and modeling of water resource health that addresses these
needed research initiatives.
NASA has defined three major tasks for success in the Earth Science Enterprise, and
they correspond to improving observations, data and information systems, and science.
1) Developing integrated observational systems based from spacecraft, aircraft,
unpiloted airborne vehicles, and on the ground and at sea.
2) Building a comprehensive data and information system to make data useful and
readily available.
3) Training the next generation of scientists and supporting them to analyze the
data collected, to build models of the earth system, and to provide
interpretations that will improve our understanding and predictive capabilities.
The scientific knowledge gained from this initiative will enable an assessment of the
impacts of climate variations on agricultural, industrial and societal activities at the
global, continental, regional and local levels in 21st Century.
Phase I of the Earth Science Enterprise is well underway, with each of the three above
tasks integrated within a series of flight missions. Phase II began in 1997 with the
coordination of these tasks within the Earth Observing System (EOS) Program. In
addition, Phase II of the Earth Science Enterprise will continue to support smaller,
unique observation projects and focused scientific investigations that require specific
platforms or time lines that cannot be achieved by the EOS or by other national and
international programs. Phase III will begin in 2000 and will benefit from scientific
knowledge gained and technological advancements achieved during Phases I and II.
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Earth Science Enterprise Components
NASA's Earth Science Enterprise's (ESE) technical science component is primarily part
of the Earth Observing System (EOS) mission, which is primarily administered through
NASA's Headquarters, Goddard Space Flight Center, Jet Propulsion Laboratory, and
Stennis Space Center. Table 3.5 highlights four major components of the ESE.
NASA continually updates information on the status of each of the ESE and EOS
projects. Interested readers are encouraged to visit the NASA ESE World Wide Web
site at http;//\vww.earth.nasa.gov to obtain current and additional data or information on
any of the ESE program components.
Table 3.5: Four Key NASA Earth Science Enterprise Missions.
Goddard Space Flight Center coordinated long term observations of climate, terrestrial
and marine ecosystems to understand earth as a unified system. Stennis Space Center
jg_g|g0_cฐPj[jinatinganEarthSystem Science initiative to study coastal ecosystems.
Jet Propulsion Laboratory coordinated long term observations of ocean ecosystems to
Jet Propulsion Laboratory and Goddard Space Flight Center coordinated, specific,
highly focused missions in earth science research to complement EOS.
Jli^lllllillMllllllilillMIMIIIilll^ ^^^^ nTrrarrrYrTT-r-trrtM^BrrirnTirriiiiTMr-iriii-itiitiTT-fiiriiiiiiifi-ir-ii i i -1 -
Stennis Space Center coordinated outreach to commercial industry to ensure U.S.
companies maintain their technological and business leadership.
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SECTION 4
WORKSHOP FINDINGS
Workshop findings are presented within this section according to breakout session type.
Four water resource categories were used to organize the breakout sessions into
groups that focused on unique monitoring needs and challenges. These four resource
groups were:
Watersheds, Rivers and Lakes
Wetlands
Groundwater
Estuaries and Oceans
For each breakout session the findings were organized into areas of: Needs and
Applicable Technologies, Gaps in Current Technologies, and Emerging
Technologies to address components of current and future monitoring missions.
Breakout Sessions
Breakout sessions were organized so that EPA and NASA personnel could exchange
insights with each other on EPA monitoring needs and appropriate NASA and other
advanced technologies. Prior to entering into the breakout sessions all participants had
been updated on the general needs of EPA water resource monitoring. EPA personnel
in each breakout session were then able to focus on monitoring needs specific to their
water resource type. NASA personnel were able to generate a list of satellite, aircraft
and stationary remote sensing devices, along with a description of their characteristics
and limitations. NASA personnel were also able to clarify the capabilities of remote
sensing systems, as well as their operational status, data availability, and the nature of
remote sensing computer analysis algorithms. Ideas for specific monitoring application /
instrument pairings appeared during the discussion.
The breakout sessions concentrated in identifying the remote sensing needs of the EPA
that could be addressed by current and emerging NASA technologies. The discussions
centered on which technologies NASA had developed that currently matched EPA
needs. Dialogue was also held on what gaps existed between current technologies and
EPA needs. Finally, a dialog was held to define possible joint efforts between the EPA
and NASA that could be undertaken to further advance technology and address the
data needs of the EPA and its partners in water resources monitoring.
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WATERSHEDS, RIVERS AND LAKES
Introduction to Watersheds, Rivers and Lakes Monitoring
The Environmental Protection Agency's monitoring activities in rivers and lakes are
mandated under the CWA and implemented primarily through delegation to states and
tribes, who submit monitoring reports to EPA biennially for the National Water Quality
Inventory Report to Congress (often called "the 305b report"). State reporting indicates
that there is more monitoring of lakes and rivers than of any other water body type.
However, less than 20% of all rivers are assessed in a typical 2-year monitoring period.
Within lakes, rivers and their watersheds, non-point source (NPS) pollution is the major
challenge because the formerly greater point source pollution problems are now mostly
under more effective controls. The importance of NPS pollution is closely linked to
activities in the watershed in a vast number of cases, and thus watershed monitoring is
an essential part of the need for understanding and managing the sources of lake and
river degradation. The most commonly reported impairments of lakes and streams are
caused by (in order from the most frequent): sediments, pathogens, nutrients, metals,
dissolved oxygen depletion, habitat or flow alteration, pH, elevated water temperature,
pesticides, mercury, inorganics, ammonia, toxic organics, and chlorine.
In most monitoring areas remote sensing technology cannot make a direct, quantitative
measurement of the chosen water quality parameter (e.g., suspended sediment
concentration in mg L"1 or ppm, the concentration of nitrate nitrogen in mg L'1, etc.).
Scientists with only remote measurements have instead had to rely upon empirical
relationships between surrogate indicators and the parameters of interest to monitor
these water bodies. Some of these methods have been relatively successful as long as
field calibration and measurement limits are observed. Thermal pollution is an
exception, however, because the thermal sensors in satellite and airborne platforms
can directly measure the temperature of the water resource at the surface. In contrast,
remote sensing of watershed characteristics associated with stress on water bodies has
been more limited. Success in this area has been limited to activities such as land
use/land cover analysis along with specific measurements of human activity (such as
amount of impervious surface, or linear measurement of denuded vs. intact riparian
woodlands). Monitoring watershed changes is therefore a very broad applications area
of proven potential.
Breakout Session Findings
The purpose of the watersheds, lakes, and rivers Breakout Session was to: 1) identify
matches between current technology and watershed, lakes, and rivers management
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and monitoring requirements, 2) examine EPA needs that could be satisfied using
NASA technology, 3) identify gaps between EPA's needs and NASA's current
technology, 4) examine ways to solve EPA's needs with existing or planned future
technology provided by NASA, and 5) identify a joint effort project which could be used
to advance the means by which EPA handles wetland management issues. The final
goal of the Breakout Session was to report these findings and make recommendations.
Because watersheds are the geographical unit defining the boundary of all water
resources, the workshop organizers recognized that the findings of this Breakout
Session were potentially applicable to the three other resource Breakout Session
groups (wetlands, groundwater and estuaries/oceans). Therefore, the watershed
findings listed in this session should be considered relevant to all the Breakout
Sessions that follow.
PRECIPITATION ANALYSIS
Needs and Applicable Technologies
By measuring precipitation water resource managers are able to predict the inputs or
loading to such resources as rivers, lakes, wetlands, groundwater, estuaries, and
oceans. Precipitation data not only provides an estimate of resource inputs and
therefore information on possible droughts and floods, but precipitation data also
enables calculations of residence times and water quality. Given the importance of
precipitation data and the limitations of rain gauges for measuring spatially distributed
rainfall, scientists are utilizing remote sensing to quantify precipitation input across large
areas.
Satellites using visible, near-infrared, and thermal sensors are capable of estimating the
spatial extent and movement of potentially rain-producing clouds, but the precipitation
below the clouds goes undetected by the above electromagnetic bands. Useful cloud
data are obtained from the polar orbiting NOAA (National Oceanic and Atmospheric
Association) satellites and the geostationary GOES (Geostationary Operational
Environmental Satellites) satellites. Visible, near-infrared, and thermal sensors are
capable of indexing clouds based on cloud type and tracking the life history of various
clouds by using a combination of visible and thermal sensor types across daylight and
darkness periods. GOES Infrared images are useful for predicting heavy precipitation
and flashfloods at temporal resolutions between 5 and 60 min and at spatial resolutions
of 4 km.
Ground based radar remote sensing using microwave sensors does penetrate through
clouds and allow for accurate estimates of precipitation intensities and volumes across
large areas. The Weather Service operates more than 120 NEXRAD (Next Generation
Radar) WSR-88D (Weather Surveillance Radar - Dpppler) stations capable of
retrieving measurements in 1 to 4-km spatial resolutions at 5 to 60-minute intervals
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within a region with a radius of approximately 225-km. These measurements are based
on principles of microwave scattering and attenuation of the WSR-88D signal by
raindrops, hail, snow, and other 'hydro-meteors'.
Gaps in Current Technologies
Earth orbiting satellites operating in the visible bands are incapable of penetrating the
cloud tops and imaging the actual precipitation. Ground based microwave radar is
incapable of imaging low-level precipitation without increasing the probability of radar
striking the ground and generating 'anomalous' propagation signals. By not directly
measuring low-level scattering the WSR-88D often underestimates total precipitation.
Current technologies are not capable of measuring dry and wet deposition of nutrients
and other chemical constituents that impact water quality. The problem of acid rain is an
example of where a measurement of rainfall quantity is not adequate for an
understanding of water resource condition. Sensors are needed that can distinguish
atmospheric and precipitation concentrations of common aggravating pollutants.
Emerging Technologies
TRMM (Tropical Rainfall Measuring Mission) is part of the EOS program and is a joint
U.S. - Japanese satellite operated by NASA and launched in November of 1997 with a
nominal lifetime of 3-years. TRMM objectives are to measure precipitation and
evaporation in tropical areas, which extend into the southern part of the U.S. (Texas,
Florida, etc.). The TRMM Microwave Imager (TMI) instrument has a horizontal spatial
resolution ranging from 4.4 to 45-km and is capable of retrieving precipitation
measurements at 1-km vertical increments within the entire troposphere, including the
low-level areas missed by WSR-88D.
SNOW COVER AND PACK DEPTH
Needs and Applicable Technologies
Snowfall during a precipitation event does not directly recharge water resources such
as rivers, lakes, wetlands, groundwater, estuaries, and oceans. Instead, snowfall often
accumulates to a certain pack depth during the snow season and then during the
snowmelt, it ultimately recharges water resources. Nearly all regions of the
electromagnetic spectrum provide useful information about snowpack, but no single
area provides highly accurate information on snowpack areal extent, its water
equivalent, and its physical condition. By estimating the extent, depth, and snowwater
equivalent or density of snow, predictions can be made of the volume of water held
within a watershed's snowpack.
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Low-elevation aircraft carrying gamma-radiation detectors can measure the natural
gamma radiation from the soil, and this is empirically related to an average snow water
equivalent. The NOAA operational gamma-radiation program covers more than 1400
flight lines annually in the U.S. and Canada. Snow surface albedo, which is used to
map extent, can be identified using satellite visible and thermal bands from instruments
such as Landsat ETM.
Gaps in Current Technologies
Although depth, extent, and snow water equivalent can be roughly estimated with multi-
frequency passive microwave sensors, most critical snowmelt areas still use in situ
measurements to calibrate and validate remotely sensed estimates of depth and
density.
A major gap in the current technology is the inability of sensors to measure snowpack
chemistry, particularly nitrate concentrations. During the spring thaw when the snow is
finally converted to liquid water the accumulated nitrogen is released to recharges the
rivers, lakes, and other resources. More sophisticated sensors may be able to some
day determine how much nitrogen will be released by the snowpack.
Emerging Technologies
Microwave remote sensing offers the greatest potential for measurement of snowpack
extent, depth, and water equivalent. The Special Sensor Microwave Imager (SS/MI) is
an U.S. instrument with horizontal spatial resolutions ranging from 14 to 70 km
depending on the microwave frequency. The capabilities of this instrument of predicting
snowmelt volume and timing are currently being demonstrated and examined.
Radarsat is a Canadian Space Agency microwave sensor that is currently used to
estimate snowpack extent and depth. New snowpack analysis techniques from these
Radarsat remotely sensed products are under development.
EVAPOTRANSPIRATION FROM LAND AND PLANTS
Needs and Applicable Technologies
Evaporation across entire field plots or watersheds is not readily measured directly by
in-situ or remote devices. Instead this component of the hydrological cycle is often
estimated by taking the difference in precipitation, runoff, and changes in soil moisture.
Although remote sensing does have the potential to make indirect measurements of
watershed and atmospheric properties, evapotranspiration is estimated by using
empirical relationships between sources (e.g. plants or land) and sinks (e.g. the
atmosphere), or on the closure of energy and water balance models.
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Plant based transpiration can be estimated using imagery of land cover, which is
available with AVHRR sensors. Land based evaporation can be estimated with imagery
of soil moisture and canopy areas (e.g. direct evaporation from canopy areas that
intercepted precipitation) given there are additional measurements of surface winds or
temperatures. Thermal infrared measurements are capable of providing the necessary
surface temperature estimates.
Microwave sensors are useful for measuring soil moisture states, which are used to
estimate the partitioning of incoming radiation into its latent and sensible components.
Energy balance methods partition incoming radiation into latent heat, sensible heat and
ground heat flux. The latent heat, which goes into evaporating water, is coupled with
water balance methods that partition rainfall into runoff, changes in soil moisture, and
evapotranspiration. Remote sensing can estimate incoming solar radiation by observing
cloud cover with geostationary satellites (e.g. GOES).
Gaps In Current Technologies
There are no current technologies that can directly measure evapotranspiration. There
has also been little progress made in the measurement of atmospheric parameters
such as near surface winds, temperatures, and water vapor gradients, all of which help
to estimate evapotranspiration.
Emerging Technologies
Visible and near-infrared sensors (e.g. Landsat ETM, AVHRR) that measure plant
biomass and LAI have helped to parameterize empirical evapotranspiration equations.
Thermal measurements have also been used to estimate regional scale
evapotranspiration rates due to the localized cooling effect caused by the evaporative
process, which converts energy into a latent heat form.
There are currently numerous studies conducted jointly with NASA and the U.S.
Department of Agriculture -Agricultural Research Service on using microwave
Synthetic Aperture Radar (SAR) technology to estimate soil moisture and boundary
layer conditions and parameterize energy balance models of evaporation.
WATER QUANTITY: RUNOFF, FLOODING AND WATERBODY EXTENT
Needs and Applicable Technologies
Remote sensing techniques cannot measure runoff volume or rates directly, but visible,
near-infrared, and thermal sensors can image runoff extent, flooding extent, and
waterbody extent. Multi-spectral scanning (MSS) is one form of technology available for
such measurements. Although MSS was the sensor aboard Landsat 1 - 5 that provided
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79-m resolution imaging, the same visible and near-infrared scanning technology is
available in other sensors. Landsat 4 and 5, for example, carried the Thematic Mapper
(TM) that was a 30-m mechanically scanned imaging radiometer. Landsat 7 carries a
MSS type instrument known as the Enhanced Thematic Mapper (ETM), while the
European SPOT satellite carries a visible-infrared sensor push-broom technology with
no mechanical scanning. Data from Landsat ETM, along with microwave, hyperspectral,
and aerial photography are all functional technologies for estimating runoff, flooding,
and waterbody extent.
Estimates of land cover and land use provide insight on how the precipitation inputs are
partitioned between infiltration and runoff. Many runoff and flooding studies, therefore,
use remotely sensed imagery of land cover to classify the watershed areas as: 1)
impervious and that would not allow for infiltration, 2) susceptible to erosion, and 3)
likely to serve as a water detention area or facilitate evapotranspiration. Topographic
data, in the form of digital elevation models (DEM), are also used to chart likely runoff
pathways and river networks. Both visible and microwave sensor stereopair data are
used to generate these maps using photogrammetric or interferometric techniques.
Gaps in Current Technologies
Although empirical models are available for estimating peak discharge and low-flow
discharge given estimates of rainfall, waterbody extent, and land cover type, the models
are not tested nor robust to spatial scaling and changes in land cover complexity. As
such, the current technology is inadequate for providing real-time and accurate
estimates of flow rates and volumes. Landsat ETM and AVHRR remote sensing images
in the visible are blocked by cloud cover, and when clouds are present then waterbody
extent must be measured using alternative portions of the electromagnetic spectrum,
such as microwave sensors.
Emerging Technologies
Stage-discharge relations that are calibrated estimates of discharge given flow height
are currently measured with in situ devices. Hence, flow height can be used to estimate
flow rates and volumes. Radar altimeters that identify water stage, and with Doppler
technologies water velocity, are currently planned for estimation of discharge
measurements on larger (> 250m) rivers. The Shuttle Imaging Radar (SIR) and SAR
are both new tools for imaging flood extent during all-weather conditions, day and night.
A new technology is NASA's Sea-viewing Wide Field of view Sensor (SeaWiFS) which
is capable of providing 1 to 4-km resolution images of land - water interfaces for
demarcating boundaries and estimating waterbody extent.
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WATER QUALITY
Needs and Current Technologies
Water quality in rivers, lakes, and other water resources is typically monitored in situ for
pollution that may arrive from point or NFS. Watershed managers are increasingly
using the TMDL approach to quantifying water resource condition and watershed
compliance with CWA guidelines. The TMDL approach encourages managers to map
all NFS and point source loads to see if the total load exceeds the healthy limit that the
water resource can receive. In cases where loading needs to decrease, the TMDL
approach encourages creative spatial and temporal arrangements that attempt to
maximize load reduction while minimizing the cost of that abatement strategy. These
TMDL scenarios require spatially distributed data sets from remote sensing platforms
as well as computer models or GIS technologies.
Empirical relationships between remotely sensed data and water quality are being
developed that should allow for more use of remote sensing for monitoring water
quality. As the causes of water quality problems in locations with similar geology,
climate, etc., are better understood, these remote-sensing relationships hold the key to
effectively monitoring higher percentages of the U. S. watersheds. Once a relationship
between reflectance and water quality is empirically established, remotely sensed data
can be used as input to extrapolating the information between the in situ locations to
give a complete description of the quality of the water body. Regional characterizations
of water quality will also be very effective in identifying problem water bodies and
potential "hot spots" for future sampling or attention.
Remote sensing instruments that utilize these empirical relationships are currently in
use. Chlorophyll in the upper water column is sensed using MSS, ETM, laser fluoro-
spectrography and hyperspectral imaging. Each of these methods detects the presence
of chlorophyll in plants, and the hyperspectral technique can distinguish between
different types of pigments in addition to chlorophyll. Suspended solids, particulate
matter, water clarity and turbidity can all be detected with MSS, ETM, aerial
photography and hyperspectral sensors. Fluorescences in terrestrial plants can be
detected with fluorosensors, and point discharges from pipes or barges can be detected
with MSS, ETM, hyperspectral, aerial photography.
Direct measurement of thermal water pollution is the only 'direct' measurement of a
water pollution constituent available with remote sensing technology. Sensors capable
of thermal detection include the Landsat-7 ETM thermal infrared band at 60-m
resolution.
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Gaps in Current Technologies
Contaminants within the water column determine how much incoming radiation is
adsorbed and scattered. The empirical relationships that equate the presence of a
thermal, algae, or sediment type pollutant with a certain adsorption signature are
primarily in the visible, near-infrared, and thermal wavelengths. Because clouds and
darkness block these wavelengths, their use is limited to monitoring water quality during
blue-sky conditions. Another gap in the technology is the spatial and temporal
resolution of images, which are usually retrieved at a 30-m to 1.1-km horizontal
resolution and range from 2 to 16 days for repeat imagery.
Remote sensing technology has not been developed to detect or measure dissolved
oxygen, basal oxygen demand, nitrogen and phosphorous nutrients, pathogen counts,
ammonia concentrations, and chemical constituents such as cadmium, copper, lead,
mercury, phenols, and total residual chloride. These water quality parameters are
important indicators of water quality and future remote sensing developments should
attempt to estimate their presence.
Emerging Technologies
There is active development of computer models and geographical information systems
(GIS) packages that provide quantitative and automated methods for analyzing the
large quantities of remotely sensed spatial data. The spatial analysis tools that help
organize the remotely sensed data so that interactions between land cover / land use
and the intersecting soil types, topography, and water resources are an emerging area
that will need to undergo additional advances to handle the increasing volumes of
spatial data.
The most frequently used hyperspectral sensor is AVIRIS. NASA's Airborne Visible-
InfraRed Imaging Spectrometer (AVIRIS) has 224 spectral channels ranging from the
visible to the infrared region of the electromagnetic spectrum. AVIRIS is truly a
hyperspectral technology that is capable of monitoring water resources at high spectral
resolutions when flown in high-altitude aircraft. New empirical relationships between
various water constituents and the spectral signatures detected by AVIRIS are under
development.
SOIL MOISTURE
Needs and Current Technologies
Soil moisture is an important part of the water balance and is useful for understanding
the partitioning of rainfall into infiltration and runoff, as well as for estimating watershed
evaporation. Soil moisture also determines the chemistry of the watershed, as is the
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case for redox reactions that go toward reduction in saturated soils and toward
oxidation in aerated soils. Soil moisture has traditionally been monitored using in situ
devices, most recently using a time domain reflectrometry technique that is based on
the dielectric properties of water and the soil medium. This dielectric technique can also
be used by passive and active microwave remote sensing instruments that can detect
the difference in emissivity between dry and moist soils. The SIR and SAR instruments
are active measurement tools while Radarsat is a passive measurement tool for
detecting soil moisture.
Soil moisture can also be inferred from measurements of a soil's thermal inertia.
Daytime and night-time thermal infra-red measurements of soil temperature can be
combined to deduce the thermal inertia and empirically relate this to the soil moisture.
Gaps in Current Technologies
Passive microwave devices with longer wavelengths provide greater penetration
through covering vegetation and deeper measurements into the soil, however these
measurements are limited to a coarse spatial resolution. Active microwave sensors
using SAR measurements overcome this spatial resolution limitation. Although
microwave signals can pass through vegetation the vegetation does create interference
and cause a decrease in the signal to noise ratio that in turn decreases the sensitivity of
the microwave sensor to changes in soil moisture.
Emerging Technologies
A variety of SAR devices have been flown aboard the space shuttle and high altitude
aircraft for research studies that examine soil moisture distributions and evolution.
NASA and the U.S. Department of Agriculture have flown numerous longer (L band)
and shorter (C band) microwave SAR and SIR missions in the Southern Great Plains to
better understand soil moisture measurement techniques. Many findings from these
studies are regularly being presented in hydrology and atmospheric science journals.
LAND USE / LAND COVER
Needs and Current Technologies
Land use / land cover data are fundamental to most watershed studies since they
represent the watershed's surface layer, an area responsible for determining both the
rate and fate of runoff. For most water resource managers, the most critical
components of the terrestrial ecosystem involve riparian areas, impervious surfaces,
and edge habitat. Each of these land cover types plays a dominant role in abating or
aggravating water pollution. In distributed watershed management modeling the use of
riparian areas and impervious areas would play an important role in determining
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whether the watershed was in compliance with TMDL requirements. Measurement of
aquatic habitat would be useful in determining the sensitivity of the resource to future
stresses.
Visible and near infrared remote sensing instruments (e.g. Landsat ETM, SPOT, and
the AVHRR) are the most commonly used devices for imaging land cover / land use
data. In situ data that are within the same area sampled by the remote sensor provide a
data set for performing training and later classification of the spectral imagery. After
classification the land cover / land use data product should be checked for classification
accuracy by using a separate set of field data not used in training and from a
representative section of the watershed.
Vegetation is generally sampled in the visible and near-infrared regions of the
electromagnetic spectrum. Reflectance rises sharply at the red edge, which is between
these two areas in the spectrum. Vegetation health and biomass is estimated by taking
the ratio of visible and near-infrared wavelength, thereby enhancing this red edge
effect. A typical measure of biomass or leaf area index is the NDVI or the normalized
vegetation difference index, however other index methods exist to identify vegetation
health and biomass, including the transformed vegetation index, the perpendicular
vegetation index, and the weighted difference vegetation index.
Gaps in Current Technologies
Current remote sensing instruments are limited to coarse spatial resolutions with a high
temporal resolution (e.g. AVHRR provides 1.1-km resolution images twice daily) or to
fine spatial resolutions with a coarse temporal resolution (e.g. Landsat ETM images the
same 30-m area every 16-days). Cloud cover blocks both of these wavelengths and the
technology of land use mapping is therefore extremely dependent on conditions where
fair weather coincides with fly-over and imaging dates.
Emerging Technologies
New commercial satellites are currently capable of retrieving visible and near-infrared
images at much high temporal and spatial resolutions than the existing Landsat and
SPOT sensors. These new data sets will allow for highly detailed studies that examine
the interaction of land use / land cover with changes in water quality.
The NASA the SeaWiFS aboard the SeaStar satellite, although designed for ocean
color viewing, is obtaining visible and near infrared images of the earth's land cover and
processed vegetation index products at 1 to 4-km resolution. These images are posted
on the Internet as a free product for scientific study. The availability of these images
should encourage new developments in land cover science.
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The NASA AVIRIS is flown as a hyperspectral airborne instrument. This instrument is
providing high radiometric resolution images of mineral and vegetation properties that
will potentially lead to new empirical relationships between land cover health,
classification, and remote sensing.
NASA is also flying a Light Detecting And Ranging (LIDAR) laser to measure the total
biomass between the canopy crown and the earth's surface soil layer. The LIDAR
instrument is capable of a very high vertical accuracy that will enable a precise
measurement of the entire terrestrial biomass.
TOPOGRAPHY AND TERRAIN ANALYSIS
Needs and Current Technologies
Topographic data describes the shape of the watershed terrain and is called a DEM
when it is stored as a raster matrix of elevation values. DEM data are used to identify
probable surface runoff pathways toward rivers and lakes, determine watershed areas
likely to serve as groundwater recharge or discharge areas, as well as identify
watershed areas most susceptible to erosion and deposition processes. In addition to
delineation drainage networks, watershed boundaries, and slope aspects and angles,
DEM data are used to compute topographic indices that predict the spatial distribution
saturation likelihood.
Two remote sensing techniques are currently used to generate DEEMs. The most
common technique uses two different look angles from visible sensors (e.g. Landsat
ETM or SPOT) for the same area and then estimates an elevation by using
photogrammetric techniques that derive estimates of stereo-correlation within the
stereopair of images. The other technique is called interferometry, which is a process
that uses two or more SAR images from different look angles and isolates phase
differences to compute elevation. The SAR-derived OEM's are becoming increasingly
popular.
Gaps in Current Technologies
DEM 30 and 90-m data sets for the U.S. were derived from high altitude photographs
by the USGS. The generation of high-resolution satellite derived OEMs is constrained to
isolated research watersheds and study areas due to the high cost of each satellite
scene. GTOPO30, the only global DEM, is a 30-arc second product (approximately 1-
km pixels) that was derived from a variety of national elevation maps, each with varying
vertical accuracy limits. It is critical that new DEM data sets are derived from the current
generation of government and commercial satellites.
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Emerging Technologies
Several new technologies are either operational or scheduled for launch that will
advance the current limitations of DEM data. The Shuttle Radar Topography Mission
(SRTM) is a SAR microwave device that will fly in 2000 aboard NASA's space shuttle
and use interferometric techniques to derive a 30 and 100-m resolution DEM for ail land
areas on the earth. Another mission is the ASTER is a NASA - Japanese sensor
scheduled for launch in 1999 as part of EOS that will provide 15-m stereopair products
for DEM generation for the entire globe.
NASA's LIDAR laser altimeter instrument will be flown as a special shuttle instrument
capable of distinguishing the true earth surface from the false canopy surface
measured by multi-spectral sensors such as Landsat ETM and SPOT.
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WETLANDS
Introduction to Wetlands Monitoring
The Environmental Protection Agency's activities in wetland area protection are
mandated under the Clean Water Act and administered through the EPA office of
Oceans, Wetlands, and Watersheds. EPA's wetlands program has some activity on
local as well as regional and national scales, and each of these scales has different
implications for the possible use of remote sensing instruments.
At local scales, EPA plays a major role in the process of evaluating CWA section 404
permits required of individual projects that propose to fill wetlands. To support this
activity, good detection and mapping of individual wetlands1 boundaries are of
paramount importance. Further, evaluating permit applications considers effects on
wetland functions, and may consider landscape-scale issues such as proximity to other
wetlands, or amount of wetlands in the watershed where the permit applicant is located.
Wetland functions include soil retention, soil generation, pollution trapping, and flood
mitigation.
In some cases, EPA is involved in enforcement actions that may include disputes over
wetland boundaries, loss of acreage, or loss of function. Through the Advance
Identification process, wetlands or wetland complexes of unusual value or high threat
may be labeled as potentially suitable or unsuitable for filling permits, and remote
analysis of their areal extent and/or functions and other attributes (e.g. extent of exotic
vegetation, or drainage patterns) can contribute.
At regional and national scales, EPA's wetland program is attentive to large-area trends
in wetlands acreage loss or gain, as well as any widespread degradation or loss of
function. Regional and national patterns often influence the program's priorities as well
as the permitting decisions on a local scale (e.g., a decision to deny or modify a permit
due to significant threats regionally to the type of wetland involved).
The predominant regional and national-scale issues of wetlands influence the outreach
and information transfer components of the wetland program. Thus, comprehensive
mapping of wetland extent, mapping of change in area over seasonal time steps, and
analysis of overall condition or function of wetlands are of high importance in setting
program direction. These monitoring activities differ from local-scale activities in their
impact on spatial resolution limits, areal coverage, classification detail, and cost that
remote technologies would need to provide.
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Breakout Session Findings
The purpose of the wetlands breakout session was to: 1) identify matches between
current technology and wetlands management and monitoring requirements, 2)
examine EPA needs that could be satisfied using NASA technology, 3) identify gaps
between EPA's needs and NASA's current technology, 4) examine ways to solve EPA's
needs with existing or planned future technology provided by NASA, and 5) identify a
joint effort project which could be used to advance the means by which EPA handles
wetland management issues. The final goal of the Breakout Session was to report
these findings and make recommendations. Although watersheds were discussed in
the above breakout session, the geographical unit defining the boundary of all water
resources is a watershed, and therefore the workshop organizers consider the findings
of the watersheds breakout session potentially applicable to this wetlands session.
WETLANDS MAPPING, INVENTORY AND BOUNDARY DELINEATION
Needs and Applicable Technologies
Wetlands mapping, inventory, and delineation of boundaries are necessary procedures
for a national wetlands protection program. National Wetland Inventory (NWI) maps, a
product derived from high altitude aerial photos and produced at 1:24,000 scale, are an
important tool for wetland management. NWI maps are limiting in their usefulness,
however, if there are major land cover changes between image collection and image
use or map use. Satellite images are typically less expensive per unit area of coverage
and therefore permit more frequent repeat coverage. However, accuracies in
identifying wetlands through satellite image processing have been low, especially for
wetlands a few acres or less in size. Consistent accuracy and available repeat
coverage is needed in order for scientists to update wetlands location and extent, as
well as establish association and possibly causation between changes in wetland
extent or structure and observed changes in watershed condition. Wetland managers
need wetland inventories just as they need indicators of wetland condition changes and
trends, processes that require regular sampling of the area across time.
Remote sensing applications that can accomplish some forms of broad-scale wetlands
mapping include the use of satellite-borne MSS such as Landsat ETM and SPOT,
airborne MSS, and aerial photography. These technologies, combined with improved
algorithms and classification techniques that use computer software to spectrally
identify types of wetlands, were identified for potential use.
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Microwave remote sensing with SAR is considered an active sensor technique for
measuring soil moisture values. If the soil moisture temporal patterns indicate a period
of saturation then the area is more readily classified as fitting formal wetland definitions.
Gaps in the Current Technologies
Current wetland databases and maps are not sufficient in accuracy or resolution for
detailed wetland studies. This gap is largely economic due to the cost of obtaining and
processing high-resolution data over large areas. When remotely sensed data are
combined with field observation data, the accuracy of the information on wetland
function or health can reach as high as 90% or better, which meets or exceeds the
accuracy needed for most wetland studies.
Data errors exist in the current NWI data, due to a variety of factors including change
over time. One option to improve accuracy is to overlay high-resolution MSS (Landsat
or SPOT) technology to identify and improve upon areas where the NWI data are
unclear. Pilot tests of this method should be reviewed for their suitability for NWI
updating.
Microwave radar remote sensing, both passive and active sensors, can provide
additional information for wetland mapping. Higher spatial resolution is obtained with
the active SAR device, but this is still primarily an airborne sensor and not available for
continued monitoring. The cost of covering the entire U.S. is considered too expensive
so this technology is still limited to research areas.
Forested wetlands present a unique challenge for identification of wetland boundaries
and functional attributes. The challenge is created when the forest canopies completely
obscure the soil moisture condition as well as any understory vegetation that is
indicative of wetland habitat. The use of vegetation penetrating radar may help to
delineate wetland boundaries under closed canopies. A combination of the use of
microwave radar with the NWI data maps may provide a well-balanced approach to
delineating the wetland areas, but cost per unit area must be assessed to determine
feasibility of application within limited budgets.
Emerging Technologies
In order to close some of the gaps between wetland management needs and available
technology, the problems of spatial and temporal resolution and map coverage need to
be addressed. Technicians need to better determine exactly what level of data
resolution is needed to identify wetland boundaries and develop maps of wetland
changes across time.
Incorporation of spatial map data and global positioning system (GPS) data points
(especially in the wetland permitting process) can improve the accuracy of remotely
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sensed data. Use of new high-resolution sensors and advanced processing
technologies (sub-pixel analysis) to map intrusive species, edge effects and support
enforcement and large scale studies are all areas that need to be examined as a
means of closing gaps between management needs and available technology.
High accuracy OEMs, when combined with land cover maps, provide a good data
source for examining whether wetland location coincides with topographic depressions
that accumulate water. LIDAR altimeters can provide very precise measurements of the
terrain surface that assist in this wetland verification technique.
Several technologies have been identified as possible solutions in improving the
mapping of wetland land cover and land use. These emerging techniques include the
use of high-resolution satellite MSS, multi-temporal analysis, sub-pixel analysis
techniques, fuzzy logic classification, and hyper-spectral scanners for soil and
vegetation analysis.
CHANGE ANALYSIS OF WETLAND EXTENT
Needs and Applicable Technologies
Change analysis is an important technique for assessing wetland habitats. Multi-
spectral scanners such as Landsat ETM, SPOT and airborne MSS provide advanced
technologies that can support analysis of wetland change.
Problems in wetland change analysis exist due to inconsistent data, lack of data, or too
infrequent collection of data. To achieve better detection of wetland change, the lag
time between updates should be shortened. It may be necessary in some wetlands
complexes to sample seasonally to capture the hydroperiod defining that wetland
hydrological regime. Regular images taken with MSS on Landsat ETM and SPOT
satellites, airborne MSS, together with digitized aerial photographs will improve the
ability to analyze change. SAR can also be used to reveal important information on
wetland change in soil moisture cycles.
Gaps in the Current Technologies
Change analysis is hampered by the coarse spatial and temporal resolution of satellite
images, resulting either in overly coarse or temporally limiting databases that provide
little insight to wetland change. Further problems exist in change detection due to the
quality of existing remotely sensed data. Cloud conditions, for example, that obstruct a
satellite fly-over create data holes that hamper otherwise effective change detection
algorithms. This repetitive lack of data collection due to cloudy conditions makes
wetland change analysis much more difficult. Change detection is also challenged by
the lack of resources available to perform the data analysis.
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Emerging Technologies
Change analysis would benefit from the creation of improved baseline data. Costs
could be constrained by focusing on "hot spots", thereby limiting the aerial extent of
change analysis to more manageable areas. The inclusion of advanced detection
techniques and the use of GIS should help provide a better understanding of
environmental limits, such as the tidal cycle, on wetland extent. SAR should be
considered as a means to overcome cloud cover obstruction.
NUISANCE SPECIES AND EDGE EFFECTS
Needs and Applicable Technologies
Nuisance species and edge effects in wetlands are important indicators of wetland
condition and outlook for the future. Monitoring for these wetland properties requires
more spatially and spectrally detailed sensors than those used for simply mapping the
wetland boundary, and identification of specific species is not yet achievable with
current remote sensing tools.
These monitoring tasks are best performed with high-resolution remote sensing tools.
Mapping of nuisance species and mapping of edge effects in ecotones is being done
through the use of aerial photography and airborne MSS remote sensing. The multi-
spectral data is then combined with data digitized from the aerial photos into GIS
databases to improve the spatial accuracy of boundary locations for the species.
Gaps in the Current Technologies
The current remotely sensed satellite images lack the spatial resolution to accurately
identify boundaries of invasive species encroachment. Airborne MSS, which can
provide sub-meter resolution, can better address the spatial resolution needs related to
mapping intrusive species than satellite data. The improved spatial resolution improves
the accuracy of vegetation classification of nuisance species.
Emerging Technologies
New high-resolution spatial and spectral sensors, such as NASA's AVIRIS together with
advanced processing technology, such as sub-pixel analysis, are emerging as refined
ways to map intrusive species, edge effects, and support implementation of large scale
studies.
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STRUCTURAL AND FUNCTIONAL ASSESSMENT AND TREND
ANALYSIS
Needs and Applicable Technologies
Land cover indicators of wetland health and function are needed in order to identify
troubled and stressed wetland areas that require immediate management attention.
Structural and functional wetland assessment, combined with the use of trend analysis,
provides the scientist with better tools to manage wetland areas.
Productivity and health trends in wetland areas require scientists to ask questions
regarding wetland hydrology, the production of biomass, species diversification, wetland
sustainability, and habitat mapping. All of these factors can be examined using data
remotely sensed from Landsat ETM, SPOT, or airborne MSS.
Structural degradation can also be detected through remote sensing. Structural
degradation data sensed remotely should be combined with functional degradation data
determined by other techniques such as field-testing. Additional tools for structural and
functional assessment are long-term historic aircraft imagery and aerial photography.
Modeling should test hypothesis regarding the role of wetland physical controls on
wetland function as well as identify the best remotely sensed indicators for identifying
the presence of those wetland functions.
Gaps in the Current Technologies
Modeling wetland productivity, diversity, sustainability and habitat structure is hampered
by inadequate data resolution in both the spatial and spectral region. Data on
structural degradation is either not available or not consistent enough for detailed
modeling.
Water salinity and temperature data should be included in trend analysis routines that
are exploring the possibility of wetland degradation. Wetlands are ecologically sensitive
systems that might die back with small changes in soil water temperature and salinity.
These two indicators of functional assessment are readily detected with in situ
techniques and there is a definite need to calibrate thermal infrared and microwave
SAR sensors to detect the same chemical and physical wetland features.
Emerging Technologies
Airborne electromagnetic profiling and other techniques for wetland structural
assessment and bathymetric mapping should be examined for incorporation into
watershed models. The use of laser fluorosensing should be considered as a means
for determining habitat stress.
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New technologies that also hold promise for improving structural and functional
assessment are hyperspectral scanners such as NASA's AVIRIS, new high temporal
resolution sensors such as NASA's SeaWiFS, and improved computational and
analysis algorithms for identifying habitat health.
INUNDATION AND SOIL MOISTURE IN SATURATED WETLANDS
Needs and Applicable Technologies
Detection of inundation and soil moisture can serve at least three distinct purposes for
wetland resource monitoring. First, this monitoring can demonstrate a distinct period of
saturation (e.g., the hydroperiod) that indicates compliance with formal wetland
definitions. Second, the inundation can indicate which zones are most likely redox
zones or areas of increased chemical activity. Third, inundation can help to define the
boundaries of the wetland. The reader is referred to the above Watershed, Rivers, and
Lakes breakout session to learn more about remote sensing microwave technologies
for detecting soil saturation.
Monitoring in wetlands in visible bands is limited by canopy and cloud cover obstruction,
while microwave bands are capable of passing through these obstacles. SAR and radar
altimeters are the current tools used in data collection for modeling applications. SAR
data can be very valuable in detecting saturation and flooding across the wetland
landscape, however the satellite based instruments have a coarse temporal and spatial
resolution while the airborne instruments are limited to infrequent and expensive flights.
Landsat ETM thermal bands can provide and alternative tool for measuring thermal
inertia and the extent of water in wetland areas and marshes.
Gaps in the Current Technologies
Wetland hydrologic and vegetative change across seasons, along with the frequency
and periodicity of inundation, are very important variables that need to be mapped with
future remote sensing missions and devices. Another important variable is variation of
soil moisture.
Emerging Technologies
Recent experiments with SAR and radar altimeters have provided good results in the
mapping of wetland inundation and identification of saturated areas. The estimation of
areas of inundation using high-resolution OEMs together with overlays of vegetative
maps may be a technique for improving mapping accuracy.
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SALINITY IN SOIL AND WATER
Needs and Applicable Technologies
Salinity concentrations and gradients of wetland soil and water is a critical indicator of
wetland function and health. Depending on the wetland type, either coastal or inland,
different salinity gradients are considered normal. Changes in the salinity in both
directions during tidal fluctuations may occur naturally in coastal wetlands, however
changes in salinity in inland wetlands are likely indicative of ecosystem stress and
severe disruption SAR and airborne microwave radiometry are the current remote
sensing sources of data for salinity modeling.
Gaps in the Current Technologies
The reliability of microwave remote sensing collection techniques is still uncertain.
There are a variety of experimental missions and a great need for demonstrating the
ability of the equipment to detect salinity gradients. Due to issues of data reliability
microwave data do not currently support many modeling needs.
Emerging Technologies
Investigation of improved airborne microwave radiometers that are more capable of
detecting salinity signals should be examined and field-tested.
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GROUNDWATER
Introduction to Groundwater Monitoring
Ground water within the U.S. Environmental Protection Agency is addressed in the
Office of Ground Water and Drinking Water. EPA's Office of Ground Water and Drinking
Water (OGWDW) programs include Wellhead Protection, Sole Source Aquifer
Protection, Underground Injection Control and the Comprehensive State Groundwater
Protection program. The Office of Research and Development (ORD) is the primary
research arm supporting the program offices and the environmental community. ORD
cooperates with other federal and state agencies and conducts a major grants program
to promote independent research in critical areas.
AH groundwater regulation and research supervised under EPA has traditionally
focused on point and non-point sources of contamination to groundwater resources.
EPA sub-offices and divisions develop policy and conduct research in the area of
aquifer protection, source water protection, underground injection control, wellhead
protection and underground storage tanks. Technical guidance for groundwater
remedial technologies have been established as well as measurement and monitoring
methodologies for operational and closed facilities.
EPA has cooperated with outside organizations such as the American Society for
Testing and Materials to produce a compendium of agency consensus standards.
Continuing in this cooperative mode the EPA sees a benefit to collaborate with NASA
scientists and engineers to further strengthen and improve upon groundwater protection
monitoring and modeling. Remote sensing instruments offer the potential to improve
upon traditional characterizations and monitoring techniques used by the EPA.
Monitoring of both saturated and unsaturated groundwater resources can benefit from
advances in remote sensing and other technologies. Near surface and unsaturated
monitoring might include locating groundwater inflow, the finding and monitoring
movement of contaminated sediments, and measuring organic compounds. Saturated
zone needs are focused on better determination of fractures (including subsurface) and
real-time potentiometric surface measurements.
Groundwater, unlike the other water resources discussed in this workshop, is typically
not visible above the ground surface. Monitoring techniques that use visible and near
infrared sensors may not be as advantageous to groundwater management as
application of new technologies in other areas of geophysical research, such as
advanced electrical and acoustic sensing devices. NASA's development of advanced
geophysical devices for exploration of other planets, such as the Mars Explorer mission,
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may provide spin-off technologies that benefit characterization of earth's groundwater
resources.
Breakout Session Findings
The purpose of the groundwater breakout session was to: 1) identify matches between
current technology and groundwater management and monitoring requirements, 2)
examine EPA needs that could be satisfied using NASA technology, 3) identify gaps
between EPA's needs and NASA's current technology, 4) examine ways to solve EPA's
needs with existing or planned future technology provided by NASA, and 5) identify a
joint effort project which could be used to advance the means by which EPA handles
wetland management issues. The final goal of the Breakout session was to report
these findings and make recommendations. Although watersheds were discussed in
the above Breakout session, groundwater recharge and discharge areas are contained
within a watershed (e.g. lakes and rivers), and therefore the workshop organizers
consider the findings of the watersheds Breakout session potentially applicable to this
groundwater session.
AQUIFER DELINEATION
Needs and Applicable Technologies
Aquifer delineation is critical to quantifying the volume of subsurface water reserves
available for human development and utilization. Inaccurate estimates of the aquifer
extent can lead to 'mining' of water resources that is characterized by withdrawal rates
exceeding aquifer recharge. Delineation of aquifers can also help to identify areas of
recharge and discharge within the watershed overlying the aquifer.
Hyperspectral imaging for delineation of vegetation types and their seasonal and
moisture-controlled changes is a technology that can help in defining aquifer
boundaries. Phreatic aquifers with near surface watertables can be detected with
microwave SAR devices that measure changes in dielectric properties between the
grain and water components of the soil medium.
MSS data, such as Landsat ETM imagery, as well as active and passive radar data,
can provide information as the extent of geological and geomorphologic terrain
features. These data collection techniques help to characterize the larger bounding
features of the aquifer and possibly help scientists extend point source surface
measurements to larger geographic scales.
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Gaps in Current Technologies
Groundwater monitoring data obtained from satellite sources is typically considered too
coarse in spatial resolution to solve standard monitoring needs. The frequency of the
data collection also limits detection of changes in the surface features as the respond to
groundwater and subsurface fluctuations.
Emerging Technologies
Advances in the availability of hyperspectral data along with increased spatial and
temporal resolution of microwave remote sensing data will help to characterize the plant
and soil moisture properties associated with in situ delineate aquifers. These empirical
studies will help to provide baseline measurements from which to track changes in
surface aquifer extent across time.
The use of SAR interferometry to detect phase shifts caused by the change in mass of
subsurface aquifers may be a new technology that can assist hydro-geologists define
aquifer boundaries.
AQUIFER CHANGE DETECTION
Needs and Applicable Technologies
Changes in the surface characteristics of aquifer plant communities can indicate a
change in the hydrologic properties of the underlying aquifer. Current remote sensing
instruments in the visible and near infrared bands on Landsat ETM, SPOT, and the
AVHRR are capable of detecting changes in vegetation greenness that could indicate
changes in aquifer water levels.
Microwave radar remote sensing of soil moisture can provide the same information
about aquifer surface conditions but at coarser spatial resolutions than the Landsat and
SPOT 30 and 10/20-m resolution visible bands.
Gaps in the Current Technologies
The current technologies are not capable of penetrating beneath the ground to detect
changes in the deeper portions of the aquifer.
Emerging Technologies
The SAR interferometry technologies discussed in the previous Breakout session
finding are applicable to this finding as well. It is possible that detection of aquifer phase
shifts could reveal information about aquifer changes in location and volume.
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DETERMINATION OF RECHARGE AND DISCHARGE ZONES
Needs and Applicable Technologies
Aquifer recharge zones typically extend across 85 to 95% of the aquifer surface area,
while some recharge areas provide inflow to regional flow networks and others supply
more local subsurface flow networks. Understanding the recharge of the aquifer is
critical to computing sustainable pumping rates for aquifer development and utilization.
Mapping the location of recharge zones relative to the distribution of surface
contaminants provides and indication of the risk that pollutants will enter groundwater
reserves. Visible features used by hydro-geologists to detect recharge zones include
local and more regional topographic high points and areas of fractures and fault zones.
Discharge zones are often identified as areas of topographic lows, often coinciding with
streams, lakes, and wetlands as well as areas with unusually lush vegetation compared
with surrounding patterns in the landscape.
Remote sensing instruments that utilize visible wavelengths can detect drainage and
associated vegetation patterns, as well as surface features related to fractures and fault
lines. These features can serve in mapping and monitoring groundwater recharge and
discharge zones. Remote sensing instruments that operate in the thermal region of the
spectrum can provide information on soil moisture and compaction and technologies
that operate in the microwave can also be used to estimate soil moisture. Microwave
sensors (i.e. Radar) can also be used to map land surface elevations, as well as
providing some canopy penetration in forested areas.
Gaps in the Current Technologies
More sophisticated technologies that penetrate below the ground surface to detect
changes in saturation, rock density, or the thermal signature of water, are technologies
that would help hydro-geologists better characterize recharge and discharge zones.
Emerging Technologies
NASA's AVIRIS is a hyperspectral technology that is capable of detecting slight
changes in mineral properties and plant characteristics. Development of empirically
based techniques for using AVIRIS and other hyperspectral sensors to identify the
influence of discharge zones is recommended for additional investigation. Additionally,
Interferometric Synthetic Aperture Radar and scanning LIDAR instruments are
technologies that can potentially provide detailed digital elevation models. The
limitations of these technologies need to be explored in a variety of landscape types.
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ACID MINE DRAINAGE DELINEATION
Needs and Applicable Technologies
Acid mine drainage is a contaminant that can endanger surface and subsurface water
quality. Delineation of acid drainage from mines is of prime importance to many regions
of the nation where open pit mining occurred. Larger mines and their drainage areas
can be viewed in remotely sensed AVHRR 1-km data, while higher resolution Landsat
(e.g. 30-m) and SPOT (e.g. 10/20-m) imagery are needed to analyze smaller mines that
may reside within complex terrain. Re-visitation rates of approximately two weeks after
major meteorological events are optimal to make contributions to EPA's acid mine
drainage monitoring program.
Gaps in the Current Technologies
Current remote sensing instruments do not allow for a comprehensive detection of the
many chemical contaminants, mineral precursors to acid mine drainage, and the
gradients of chemical concentrations found in mine drainage areas. Characterization of
the topography surrounding and within the mine area is another problem. The current
spatial resolution of most airborne and space borne sensor systems is inadequate to
resolve the effects that occur in the smaller streams that usually occur adjacent to the
mines.
Emerging Technologies
Hyperspectral remote sensing instruments, such as the AVIRIS, and Multispectral
Thermal instruments, such as the Thermal Infrared Multispectral Scanner (TIMS) and
the MODIS (Moderate Resolution Imaging Spectrometer) - ASTER simulator (MASTER)
have the potential to discriminate between a variety of chemical constituents and
mineral precursors and better detect the high risk from the benign minerals and waters
that are also distributed about the mine area as well as having the potential to detect
vegetation effects at very early stages of damage. These airborne systems have space
borne equivalents as part of the Earth Observing System (i.e. MODIS, ASTER, and EO-
1's Hyperion). Interferometric Radar and Topographic LIDAR systems may also be
available from air borne and space borne platforms to characterize topography for risk
assessment and management.
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SALINITY MAPPING
Needs and Applicable Technologies
Salinization of soil and water may jeopardize both environment health and agricultural
productivity. Salinization can occur within an aquifer due to evaporation drawing
dissolved minerals and salts toward the surface and due to groundwater pumping
accidentally drawing adjacent salt-water reserves into the aquifer.
Microwave SAR instruments have been used as a screening tool to identify areas
where in situ research is needed to investigate the risk of Salinization.
Gaps in the Current Technologies
Remote sensing instruments are currently unable to detect areas were salt-water
intrusion into freshwater aquifers is occurring. These subsurface measurements require
knowledge of pumping rates, aquifer draw down, and the proximity of bounding salt-
water aquifers.
Emerging Technologies
Development of airborne electromagnetic and magnetometer capabilities to detect
Salinization impacts should be focused on relatively small, cost-effective studies that
use a combination of spaceborne, airborne, and surface remote sensing. These studies
should help to develop the use of advanced technologies for ground water applications.
GROUNDWATER SUBSIDENCE
Needs and Applicable Technologies
Groundwater subsidence describes the lowering of ground-surface elevations due to
changes in the potentiometric pressure of the underlying aquifer. When groundwater
withdrawal rates exceed recharge rates subsidence has an increased potential to
occur. Remote sensing instruments may not be capable of gauging the imbalance of
pumping and recharge rates, however the use of high-precision altimeters, such as the
LIDAR laser altimeter, together with GPS technology can help to monitor changes in
ground elevation.
Gaps in the Current Technologies
The working groups identified no gaps in current technologies, but instead noted the
lack of application.
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Emerging Technologies
Microwave SAR interferometry and LIDAR laser altimeters are both capable of
detecting terrain elevation. The SAR interferometry technology is not as precise as the
LIDAR laser altimeter and initial detection of subsidence will likely be clearer on the
LIDAR systems. For larger areas, however, the SAR interferometer will provide a more
cost-effective measurement technique.
DETECTION OF POTENTIOMETRIC SURFACE
Needs and Applicable Technologies
A fundamental parameter for hydro-geological monitoring and modeling is the aquifer
potentiometric surface. These spatially distributed measurements of aquifer pressure
indicate the flow path directions and help to detect areas of recharge and discharge.
Both surface and subsurface aquifers have a potentiometric surface, and the shape of
the watertable defines the surface aquifer's potentiometric surface.
In situ measurements with wells and piezometers are traditionally the measurement
technique of choice for potentiometric mapping. Advances in remote sensing
instruments have not provided any practical tools for monitoring potentiometric
surfaces. NASA may develop other advanced geophysical techniques, however, that
help in the monitoring of this fundamental aquifer property.
Gaps in the Current Technologies
There is a need to investigate potentiometric surface mapping applications for the
advanced geophysical technologies developed by NASA and other technology based
industries.
Emerging Technologies
No existing technologies were identified as likely candidate geophysical tools for
advancing remote sensing of potentiometric surfaces.
OTHER GROUNDWATER MONITORING NEEDS
The Groundwater Breakout session created an additional list of monitoring needs that
could benefit from remote sensing or advances in geophysical detection methods.
These monitoring needs were for near surface water resources that were either
monitored near the surface (Table 4.1) or below the surface (Table 4.2).
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Table 4.1. Monitoring Needs for Near Surface Measurements
r\ v>x -sT* S iป *-4 x *^ *- *N
,x*- xoS^Tป ซซ&-*? .-^ux. lซa, vsป2*
Current technologies cannot accurately define zones of groundwater inflow in
harbors, bays, estuaries, riparian zones.
The Army Core of Engineers uses capping as the major means of isolating
contaminated sediments. There is currently no reliable method to monitor
advection through the cap.
fr
w
(j,-,.
Current design is ad/hoc. There is a need to develop a system for real-time
monitoring of flow and collection of samples. Could also be used for riparian
zones.
New containment strategies require better methods for location and
measurement of biodegradation.
Need research and development for real-time monitoring, this includes
development of sensors and placement methods such as moles.
Enhance the quality of seismic surveys, both reflection and refraction.
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Table 4.2. Monitoring Needs for Below Surface Measurements
Wells and piezometers measurements are not a cost-effective method of
accurately determining head relationships over large distances. Need better
application of geophysical methods.
Monitoring penetration depth could possibly be enhanced by combining rotary
and vibratory methods with push methods.
fv
Need research and development for real-time monitoring, including development
of sensors and placement methods such as moles.
Develop horizontal emplacement to monitor areas under containment fractured
Assess the cost:benefit ratio of further technologies in 3-D geophysical
monitoring and development.
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ESTUARIES AND OCEANS
Introduction to Estuaries and Oceans Monitoring
Some of the most important applications of satellite and airborne remote sensing are in
data extrapolation and modeling, the planning of field sampling, and the ability to put
data from local studies into a regional perspective. The EPA Office of Oceans,
Wetlands, and Watersheds is involved in using large ocean and estuary data sets to
monitor and manage the earth's ocean ecosystem.
Most EPA data comes from in situ and point measurements. For ocean resources,
however, that is not a practical sampling technique. Given the vast spatial scales that
describe the earth's ocean it is critical to use remotely sensed measurement techniques
together with in situ measurements so that monitoring can occur across a greater
percentage of the ocean's expanse. In situ data help to calibrate remotely sensed data,
detect sampling bias, and develop empirical equations that equate remotely sensed
measurements with water parameters of interest.
Although NASA satellite and aircraft instruments appear to operate at coarse spatial
scales compared to landscape heterogeneity, the relatively homogeneous surface of
the ocean makes the NASA technologies a very appropriate monitoring design. The
sensors are incapable of detecting ocean properties at great depths, however, future
hyperspectral sensors may be useful for characterizing submerged aquatic vegetation
such as macro-algae and sea grasses.
Breakout Session Findings
The purpose of the estuaries and oceans Breakout session was to: 1) identify matches
between current technology and estuaries and oceans management and monitoring
requirements, 2) examine EPA needs that could be satisfied using NASA technology, 3)
identify gaps between EPA's needs and NASA's current technology, 4) examine ways
to solve EPA's needs with existing or planned future technology provided by NASA, and
5) identify a joint effort project which could be used to advance the means by which
EPA handles wetland management issues. The final goal of the Breakout session was
to report these findings and make recommendations. Although watersheds were
discussed in the above Breakout session, the watershed and its rivers and lakes are
the hydrological resources draining into estuaries and oceans, and therefore the
workshop organizers consider the findings of the watersheds Breakout session
potentially applicable to this estuaries and oceans session.
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WATERSHED IMPACTS ON ESTUARY WATER QUALITY
Needs and Applicable Technologies
The combined effect of upslope watershed activities on downstream water quality has
not been regularly studied. EPA, NASA (through the Earth Science Enterprise), and
other agency research programs, however, are pursuing research activities that are well
distributed within the watershed area, from headwater regions to the estuary and ocean
receiving waters. Coordinating the data storage from these multiple research projects
will allow for integrated assessment of watershed impacts on estuary and ocean water
quality.
One the specific problem involves the effect of combined sewer overflows on
downstream water quality. During precipitation events, raw sewage is dumped directly
into the estuaries from many coastal communities. These effects could be estimated
through the use of the appropriate remotely sensed data such as hyperspectral, high
resolution MSS, and laser fluorosensors.
Remote sensing systems may also be useful for determining the effects of natural
disasters such as hurricanes and floods on estuaries and coastal waters. Products
developed to study the global ocean may be too coarse for coastal applications,
however raw satellite data can often be processed and optimized for coastal
applications.
Gaps in the Current Technologies
Integrated and regional watershed monitoring programs that address both baseline and
trend data are needed. Statistically based monitoring programs that are well designed
to isolate the impact of watershed changes on water quality impacts can provide useful
information for designing pollution abatement devices. Estuary sampling should try to
isolate water and sediment quality, animal tissue samples, and air quality as a function
of watershed changes that are detectable with advanced monitoring methods.
Emerging Technologies
NASA investigators are using new fluorometric techniques that should enhance
monitoring of estuarine chemistry. Hyperspectral remotely sensed data from
instruments such as the AVIRIS offers an alternative technology that promises to better
identify and characterize the chemical signals of contaminants and other components of
estuaries.
NASA's SeaWiFS that is carried by the SeaStar satellite is capable of retrieving 1 to 4-
km resolution images of estuary and ocean temperature along with upslope watershed
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vegetation indices. The data from the SeaWiFS sensor is made available to the general
public over the Internet within one-day after image capture. This is an emerging
technology that will likely advance integrated estuary and wetland analysis.
LARGE ESTUARIES AND COASTAL WATERS
Weeds and Applicable Technologies
Ocean color data is a standard monitoring product that indicates the presence of
photosynthetically active pigments such as chlorophyll-a. By tracking intensities and
changes in ocean color, scientists are capable of estimating the biological productivity
of the ocean. MSS measure biological productivity in ocean, estuaries and coastal
areas.
Gaps in the Current Technologies
Ocean color analysis must distinguish between surface reflectance caused by
photosynthetically active pigments and reflectance caused by suspended sediments
and DOC. Because the suspended sediments and DOC are usually recorded in coastal
waters it is not a significant limitation that the remote sensor has trouble distinguishing
between these two sources of color.
Emerging Technologies
The Ocean Color and Temperature Scanner (OCTS) on the ADEOS-1 (Advanced Earth
Observing Satellite) spacecraft has been collecting ocean color data over the US
coastal waters since November 13, 1996. The National Oceanic and Atmospheric
Administration has recently begun distributing real-time data products based on
imagery from this satellite through its Coast Watch nodes. These data products are
available for research purposes and for government, including state and local
operations. OCTS collects data over the US coastal waters (including the Great Lakes)
once every two days. Standard collection products, with a resolution of 0.8 km (pixel
size) include: phytoplankton chlorophyll; water clarity indices; sea surface temperature;
dissolved organic matter estimates; and suspended sediment estimates.
TURBID COASTAL WATERS
Needs and Applicable Technologies
Turbid waters are more challenging for remote sensing and traditional monitoring due to
the turbulence created by the severe wave and wind action. Oceans are continually
moving due to storms and currents, however, and advanced technologies need to
monitor the condition of the ocean and estuary waters under a variety of conditions.
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Gaps in the Current Technologies
As mentioned above, MSS operating in the narrow visible band used for ocean color
sampling are incapable of readily distinguishing between sediment and DOC
reflectance and chlorophyll reflectance. Because turbid waters stir up bottom
sediments, the suspended sediment and DOC reflectance measurements are typically
of turbid waters. Therefore, combined with measurements of wave height and spectra,
reflectance spectra can be assigned to either chlorophyll or sediment and DOC
sources.
Emerging Technologies
The OCTS, which holds great promise in large estuary and coastal water applications,
has not been as effective for turbid coastal areas. The algorithms for calculating
chlorophyll and other products do not yet work as well in coastal waters as they do
offshore. Therefore, one has to be very careful how these products are interpreted for
estuarine and coastal waters.
NASA's SeaWiFS is capable of retrieving 1 to 4-km resolution images of estuary and
ocean temperature and reflectance data. These data from the SeaWiFS sensor are
regularly made available and is an emerging technology that should advance turbid
water analysis..
OCEAN AND ESTUARIES - GENERAL PROGRAM
Needs and Applicable Technologies
Estuary and ocean boundary delineation is important for resource management and
monitoring. The use of high spatial resolution data along with higher spectral resolution
MSS or hyperspectral data will improve modeling of riparian zones, coastal boundaries,
and species habitats.
Digital elevation data of the water surface are important for detection of ocean currents
and waves. High-resolution OEMs provide needed data for these monitoring activities.
Change analysis is fundamental to a complete estuary and ocean monitoring program.
Databases must account for temporal (seasonal) change as part of standard estuary
analysis. Maintaining a high accuracy of baseline data is critical for effective change
analysis modeling, while development of historical databases also becomes important
for longer-term studies. These databases need to be maintained with metadata that
clearly describes data capture and manipulation procedures and then and ultimately
stored in a location where they can be easily accessed.
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Gaps in the Current Technologies
The current DEM maps are too coarse in resolution for many monitoring application,
while the emerging technologies discussed in the Watersheds, Rivers, and Lakes
breakout session are likely to advance the science of DEM analysis. The use of both
radar altimeter and LIDAR laser altimeter data should improve the spatial resolution of
the elevation data collected.
The ERS-1 and Radarsat Satellites with radar imagers, altimeters, and scatterometers,
can be used for studying ocean dynamics, such as waves, currents and fronts. The
use of these attributes can lead to better understanding of the global climate, pollutant
movement, coastal processes and physical oceanography.
Small aircraft sensors such as MSS, video cameras, thermal infrared, and microwave
radiometers have the attributes of high spatial resolution and are multi-spectral. The
above sensors are likely applicable to the advanced study of coastal-estuarine
processes and can remotely monitor properties such as ocean color, temperature,
salinity, features, plumes, fronts and. These attributes allow for monitoring of tidal
effects, plankton blooms, and pollutant dynamics.
The European Space Agency ERS-2 and the ADEOS-2 NASA Scatterometer (NSCAT)
sensors that are presently operational and measure wind velocities over the ocean.
The footprint of these sensors is 15-km or greater, which constrains their use in coastal,
estuarine and Great Lakes monitoring.
Emerging Technologies
Color scanners such as SeaWiFS, OCTS, Landsat-7, hyperspectral scanners, and the
AVHRR, for sea surface temperature, provide scientists with additional tools for water
quality monitoring. Aircraft tools include hyperspectral imagers such as the AVIRIS,
which flies at high altitude on sophisticated aircraft, and smaller hyperspectral imagers,
that can fly on low altitude aircraft which are relatively inexpensive to operate.
Better algorithm techniques are being developed for these emerging technologies to
more accurately identify ground items according to their spectral signature.
SeaWiFS successfully launched into orbit in 1997. Data are available from NASA for
research purposes and direct real-time reception of data is available for commercial and
government purposes. It is possible to purchase a license to receive these data from
Orbital Sciences Corporation. This satellite collects information about ocean color,
chlorophyll, temperature, dissolved organic compounds, pollutants, etc. Its applications
range from studying ocean productivity, fisheries management and pollution control to
marine biology. Some of the problems that are inherent to this system involve the need
for calibration of the collected data. Algorithms need further development to overcome
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problems with atmospheric correction. Another data sensing problem is in the lack of
days in which remote sensing can take place due to cloud cover.
NASA's MODIS is an advanced NASA ocean color scanner scheduled for launch in
1999 on the EOS-Terra platform.
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APPENDIX A
WORKSHOP AGENDA
December 11.1996
7:30-8:15am Registration
8:15-8:45am Welcome and Introductory Remarks
Dr. Nancy G. Maynard, Deputy Director, Science Division, NASA's
Office of Mission to Planet Earth (OMTPE)
Dr. Joe Alexander, Deputy Assistant Administrator for Science,
EPA's Office of Research and Development (OR&D)
Dana Minerva, EPA's Deputy Assistant Administrator of Water
8:45-10:15am EPA's Water Monitoring Mission Tutorial
Elizabeth Fellows, Chief, Monitoring Branch, "EPA's Water
Monitoring Mission"
Douglas Norton, Watershed Branch, "EPA's Water Monitoring
Needs"
10:15-10:30am Break
10:30-12:00pm NASA' Remote Sensing Tutorial
Dr Ghassem Asrar, Earth Observing System (EOS) Chief Scientist,
"Mission to Planet Earth Program"
Dr. Ramapriyan, Earth Science Data Information System (ESDIS),
"Earth Observing System Data Information System (ESDIS)"
12:00-1:45pm Lunch
Luncheon Speaker: Dr. Charles G. Groat, Director, Center for
Environmental Resource Management, University of Texas at El
Paso.
1:45-2:OOpm Breakout Panel Instructions; Douglas Norton, Watershed Branch.
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2:00-5:00pm Joint EPA/NASA Breakout Panels (w/working break)
1) Wetlands (Co-Moderators: Dr. Vic Klemas-NASA and Peter
Stokley-EPA)
2) Watersheds, Lakes, Rivers (Co-Moderators: Barry Burgan-EPA
and Dr. Ted Engman-NASA)
5:30-7:00pm Reception
December 12.1996
8:00-11:30am Joint EPA / NASA Breakout Panels (w/working Break)
1) Oceans and Estuaries (Co-Moderators: Dr. James Yoder-NASA
and Joe Hall-EPA)
2) Groundwater (Co-Moderators: Joe D'Lugosz-EPA and Dr. James
Arnold-NASA)
11:30-1:00pm Box Lunch
1:00-1:30pm EPA/NASA Summary Findings and Recommendations-Wetlands Panel
1:30-2:00pm EPA/NASA Summary Findings and Recommendations-Watersheds,
Lakes Rivers Panel
2:00-2:30pm EPA/NASA Summery Findings and Recommendations-Oceans, and
Estuaries Panel
2:30-3:00pm EPA/NASA Summary Findings and Recommendations-Groundwater
Panel
3:00-3:30pm Concluding Statements (Alex Tuyahov, NASA and Steve Lingle, EPA)
December 13.1996
8:00-12:00am Breakout Panel EPA / NASA Co-Moderators prepare Draft Workshop
Report
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APPENDIX B
REMOTE SENSING DATA SOURCES AND INFORMATION
EARTH OBSERVATION SATELLITES: PAST
The following table includes those satellites that are no longer operational. It is limited
to sensors that were intended for remote sensing of the Earth surface.
Table Appendix B.1. Listing of Past Earth Resource Satellites
Landsat-2 us 1975-1982 MSS Multispectral
RBV
Video
Landsat-3 US 1978-1983 MSS Multispectral
RBV
Video
79
79
240
30
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">. w
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.^w/ ^ -* J
825-1000
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Table Appendix B.1. Continued. Listing of Past Earth Resource Satellites
NOAA-6 US 1979-1987 AVHRR Multispectral
NOAA-8 US 1983-1985 AVHRR Multispectral
MOS-1 Japan 1987-1995 MESSR Multispectral
VTIR Multispectral
MOS-1 b Japan 1990-1996 MESSR Multispectral
VTIR Multispectral
50
900
2700
50
900
2700
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EARTH OBSERVA TION SA TELLITES: CURRENT
The following table includes those satellites that are operational. It is limited to sensors
that are intended for remote sensing of the Earth surface.
\
Table Appendix B.2. Listing of Current Earth Resources Satellites
fNซ5*ซ?<$ VJ%~ ***;, o -*&**
120 ^fj:
Landsat-5 US
1984
MSS Multispectral
TM
Multispectral
82
30
120
NOAA-10
US
1986 AVHRR Multispectral
1100
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Table Appendix B.2. Continued. Listing of Current Earth Resources Satellites
Satellite Dates of
Name Source Launch Sensors
Types
No. of
Channels
Resolution
(meters)
SPOT-2 France 1990 HRV Multispectral 3
Panchromatic 1
US 1991 AVHRR Multispectral
JERS-1 Japan 1992
OPS Multispectral
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Table Appendix B.2. Continued. Listing of Current Earth Resources Satellites
jLaunch
I'-fi IfeffSHifrpf"^ Resolution'
Ii&PiskS^ifittannelsy," -:.(rriejters) J
<'*> \f
NOAA-14 US 1994 AVHRR Multispectral
1100
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L-'W-C i^" v'jป '''*'>ซ*ซ ^ %^ - ^A' ^ vVป^'-*ป ,j, >4- ^"- ^.y
^'^7^ ^,^7;l,ndla_^ ^fM,^',^. .'.j^^* \v ^ r -^ v\-> '--' ^./^*.st
^^w. ^ , ป> ' > >" ซ- -4
'Pan '/" , Panchfigttnatic ,.
ERS-2
ESA
1995
AMI
Radar
ATSR Multispectral
26
1000
*\ i-o-
g^ Canada .>j"99$' 2^4 SAH:^ ^''l^ ^Ra<|af''' ;jj-i**
*%,.*
ADEOS Japan 1996 OCTS Multispectral
AVNIR Multispectral
Panchromatic
16
16
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EARTH OBSERVATION SATELLITES: FUTURE
The following table includes those satellites that were planned for future operation at
the time of the Workshop. It is limited to sensors that are intended for remote sensing
of the Earth surface. Updates on the status of various sensors are provided where
possible. Keeping the perspective of this list from the vantage point of 1996 helps the
reader understand what the Workshop participants considered future technologies.
Table Appendix B.3. Listing of Future Earth Resource Satellites
74
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Space
Imaging /
IKONOS EOSAT
1998
failed
Space
Imaging Multispectral
Panchromatic
Table Appendix B.3. Continued. Listing of Future Earth Resource Satellites
Satellite-;
Name
. Source
No, of
Channels?
Resolution
SPOT-4
France
1998
in-orbit
VI
Multispectral
HRV Multispectral
Panchromatic
1000
20
CBERS China/Brazil 1999
CCD Multispectral
IRMSS Multispectral
20
180
75
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Table Appendix B.3. Continued. Listing of Future Earth Resource Satellites
QuickBird
Multispectr
2000 al Multispectral
Panchrom
atic Panchromatic
3.2
0.82
76
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Table Appendix B.3. Continued. Listing of Future Earth Resource Satellites
IKONOS 2
1999
Space Space
Imaging in-orbit Imaging
Multispectral
Panchromatic
NOAA-L
US
2000 AVHRR Multispectral
1100
*.
us
Radar
3-100
ADEOS-II Japan
1999
GLI Multispectral
34
250-1000
77
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2000 MODIS Multispectral
Table Appendix B.3. Continued. Listing of Future Earth Resource Satellites
Satellite Expected
Name Source Launch .Sensors
No. of Resolution
Types Channels (meters)
ALOS
Japan 2002
VSAR
Radar
10
AVNIR-2 Multispectral
Panchromatic
10
2.5
SPOT-5 France 2002 HRV Multispectral
78
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APPENDIX C
EPA/NASA WORKSHOP ON WATER MONITORING, REMOTE
SENSING, AND ADVANCED TECHNOLOGIES ATTENDANCE LIST
Joe Alexander
USEPA
401 M Street SW
Washington, DC 20460
Phone:
Fax:
E-mail:
John Anderson
Virginia Institute of Marine Sciences
Gloucester Point, Virginia 23062
Phone: 1-804-642-7182
Fax: 1-804-642-7335
E-mail: johna@vims.edu
Jim Arnold
Virginia Institute of Marine Sciences
Gloucester Point, Virginia 23062
Phone: 1-202-358-0540
Fax: 1-202-358-2770
E-mail: jim.arnold@hq.nasa.gov
Roger C. Bales
Department of Hydrology & Water
Resources
University of Arizona
P.O. Box21001
Tucson, Arizona 85721
Phone: 1-520-621-7113
Fax: 1-520-621-1422
E-mail: roger@hwr.arizona.edu
Jim Brass
NASA
Ames Research Center
MS 242-4
Moffett Field, California 94035
Phone:
Fax:
E-mail: jbrass@mail.arc.nasa.gov
Don Brown
USEPA - ORD
26 W. M. L. King Drive
Cincinnati, Ohio 45268
Phone:-513-569-7630
Fax: 1-513-569-7185
E-mail: brown.donald@epamail.epa.gov
David Burden
USEPA - NRMRL
P.O. Box1198
Ada, Oklahoma 74820
Phone: 1-405-436-8606
Fax: 1-405-436-8597/8614
E-mail: burden@ad3100.ada.epa.gov
Barry Burgan
USEPA
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-7060
Fax: 1-202-260-1977
E-mail: burgan.barry@epamail.epa.gov
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Virginia Burkett
U.S. Geological Survey
National Wetlands Research Center
700 Cajundome Boulevard
Lafayette, Louisiana, 70506
Phone: 1-318-266-8636
Fax: 1-318-266-8592
E-mail: burkettv@nwrc.gov
Janet W. Campbell
University of New Hampshire
Ocean Process Analysis Laboratory
Morse Hall
Durham, New Hampshire 03824
Phone: 1-603-862-1070
Fax: 1-603-862-0243
E-mail: Campbell@kelvin.sr.unh.edu
Jeff Chanton
Florida State University
Dept of Oceanography
Tallahassee, Florida 32306-3048
Phone: 1-904-644-7493
Fax: 1-904-644-2581
E-mail: jchanton@mailer.fsu.edu
Paula G. Coble
University of South Florida
Department of Marine Science
140 Seventh AveS
St Petersburg, Florida 33701
Phone: 1-813-893-9631
Fax:
E-mail: pcoble@seas.marine.usf.edu
Tim Collette
USEPA - ORD
Ecosystems Research Division
960 College Station Road
Athens, Georgia 30605
Phone: 1-706-355-8211
Fax: 1-706-355-8202
E-mail: collette.tim@epamail.epa.gov
Tod Dabolt
USEPA
Mail Code 4503F
OWOW
401 M Street SW
Washington DC 20460
Phone: 1-202-260-3697
Fax:
E-mail: dabolt.thomas@epamail.epa.gov
Thomas J. Danielson
USEPA
Mail Code 4502F
Wetlands Division
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-5299
Fax: 1-202-260-8000
E-mail: danielson.tom@epamail.epa.gov
Joseph J. DLugosz
Research Hydrologist
National Health and Environmental Effects
Research Laboratory
Mid-Continent Ecology Division
6201 Congdon Boulevard
Duluth, MN, 55804-2595
Phone: 1-218-720-5550
Fax: 1-218-720-5539
E-mail: jdlugosz@michigan.dul.epa.gov
Maria Downing
USEPA
726 Minnesota
Kansas City, Kansas 66215
Phone: -913-551-7362
Fax:
E-mail: downing.marla@epamail.epa.gov
Peter R. Jutro
USEPA
Mail Code 8106
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-5937
Fax:
E-mail: dutro.peter@epamail.epa.gov
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Dr Edwin T Engman
Code 974
NASA, Goddard Space Flight Center
Greenbelt, MD 20771 USA
Phone: 301-286-5355
Fax: 301-286-1758
tengman@neptune.gsfc,nasa.gov
Elizabeth Fellows
USEPA
401 M Street SW
Washington, DC 20460
Phone:
Fax:
E-mail: fellows.elizabeth@epamail.epa.gov
Murray Felsher
Associated Technical Consultants
P.O. Box 20
Germantown, Maryland 20875-0020
Phone: 1-301-428-0557
Fax: 1-301-428-0557
E-mail: mfelsher@hq.nasa.gov
Tim Foresman
University of Maryland Baltimore County
Department of Geography
1000 Hilltop Circle
Baltimore, Maryland 21250
Phone: 1-410-455-3149
Fax: 1-410-455-1056
E-mail: foresman@umbc.edu
David Friedman
USEPA
Mail Code 8104
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-3535
Fax:
E-mail: friedman.david@epamail.epa.gov
Valerie Garcia
USEPA
Mail Code 8102
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-7492
E-mail: garcia.val@epamail.epa.gov
Donald Garofalo
USEPA - ORD
12201 Sunrise Valley Drive
555 National Center
Reston, Virginia 20192
Phone: 1-703-648-4285
Fax: 1-703-648-4290
E-mail: garofalo.donald@epamail.epa.gov
Marilyn Ginsberg
USEPA
Mail Code 4606
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-8804
Fax: 1-202-260-0732
E-mail ginsberg.marilyn@epamail.epa.gov
Charles Groat
University of Texas at El Paso
Center for Environmental Resource
Management
P.O. Box 645
El Paso, Texas 78812
Phone: 1-915-747-5954
Fax: 1-915-747-5145
cgroat@utep.edu
Diane Alford Guthrie
USEPA - Region 4
Science and Ecosystem Support Division
980 College Station Road
Athens, Georgia 30605
Phone: 1-706-355-8672
Fax:
E-mail: dgutherie@epamail.epa.gov
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Joe Hall
Mail Code 4504F - OCPD
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-9082
Fax: 1-202-260-9960
E-Mail: hall.joe@epamail.epa.gov
Jack Hess
Desert Research Institute
Water Resources Center
P.O. Box 19040
Las Vegas, Nevada 89132-0040
Phone: 1-702-895-0451
Fax: 1-702-895-0496
E-mail: jack@snsc.dri.edu
Oscar K. Huh
Louisiana State University
Costal Studies Institute
Baton Rouge, Louisiana 70803
Phone: 1-504-388-2952
Fax: 1-504-388-2520
E-mail: oscar@antares.esl.lsu.edu
Mike Kearney
University of Maryland
Department of Geography
College Park, Maryland 20742
Phone: 1-301-314-9299
Fax: 1-301-405-4057
E-mail: mk11@umail.umd.edu
Darryl Keith
USEPA
Atlantic Ecology Division
27 Tarzwell Drive
Narrangansett, Rhode Island 02882
Phone: 1-401-782-3135
Fax: 1-401-782-3030
E-mail: keith.darryl@epamail.epa.gov
Stuart Kerzner
USEPA
Water Protection Division
841 Chestnut Building (3WP40)
Philadelphia, Pennsylvania 19107
Phone: 1-215-566-5709
E-mail: kerzner.stu@epamail.epa.gov
Vic Klemas
University of Delaware
College of Marine Studies
Newark, Delaware 19716
Phone: 1-302-831-8256
Fax: 1-302-831-6838
E-mail: victor.klemas@mvs.udel.edu
Art Koines
USEPA - OPPE
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-4030
Fax: 1-202-260-0275
E-mail: koines.arthur@epamail.epa.gov
Tim Kratz
University of Wisconsin
Trout Lake Station
10810 County N
Boulder Junction, Wisconsin 54512
Phone: 1-715-356-9494
Fax: 1-715-356-6866
E-mail: kkratz@facstaff.wisc.edu
Harold R. Lang
Jet Propulsion Laboratory M183-501
4800 Oak Grove Drive
Pasadena, California 91009
Phone: 1-818-354-3440
Fax: 1-818-354-0966
E-mail: harold@lithos.jpl.nasa.gov
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Steve Lingle
USEPA
Mail Code 8722 ORD
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-2619
Fax: 1-202-260-4524
E-mail: lingle.stephen@epamail.epa.gov
George Loeb
USEPA
Mail Code 4504F - OWOW
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-0670
Fax: 1-2020-260-9960
E-mail: loeb.george@epamail.epa.gov
W. Berry Lyons
University of Alabama
Department of Geology
Box870338
Tuscaloosa, Alabama 35487-0338
Phone: 1-205-348-0583
Fax:1-205-348-0818
E-mail: blyons@wgs.geo.ua.edu
Thomas H. Mace
USEPA
Mail Code MD-34 OIRM
Research Triangle Park, NC 27713
Phone: 1-919-541-2710
Fax: 1-919-541-7670
E-mail: mace.tom@epamail.epa.gov
Tom Maddock
University of Arizona
Department of Hydrology
Harshberger Bldg
Tucson, Arizona 85271
Phone:1-520-621-7115
Fax: 1-520-621-1422
E-mail: maddock@hwr.arizona.edu
Nancy Maynard
Science Division - Code YS
300 E Street SW
Washington, DC 20546
Phone: 1-202-358-2559
Fax: 1-202-358-2770
E-mail: nancy.maynard@hq.nasa.gov
John Melack
University of California Santa Barbara
Environmental Science and Management
Santa Barbara, California 93106
Phone: 1-805-893-3879
Fax: 1-805-893-4724
E-mail: melack@lifesci.ucsb.edu
Rick Miller
NASA
Earth System Science Office 5AOO
Stennis Space Center, Mississippi 39529
Phone: 1-601-688-1904
Fax: 1-601-688-1777 .
E-mail: richard.miller@ssc.nasa.gov
Leslie Morrissey
University of Vermont
School Natural Resources
Burlington, Vermont 05405
Phone: 1-802-656-2695
Fax: 1-802-656-8683
E-mail: lmorriss@nature.snr.urm.edu
Peter H. Murtaugh
USEPA - Region 8
GIS RF3
999 18th Street, Suite 500 (8TMS-D)
Denver, Colorado 80202-2466
Phone:
Fax:
E-mail:
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John Mustard
Brown University
Department Geological Science
Box 1846
Providence, Rhode Island 02912
Phone: 1-401-863-1264
Fax: 401-863-3978
E-mail: john.mustard@brown.edu
Doug Norton
USEPA
Mail Code 4503F
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-7017
Fax: 1-202-7024
norton.douglas@epamail.epa.gov
Jeff G. Paine
University of Texas at Austin
Bureau of Economic Geology
University Station
BoxX
Austin, Texas 78713
Phone: 1-512-471-1260
Fax: 1-512-471-0140
E-mail: paine@begu.beg.utexas.edu
Earnest D. Paylor II
NASA
Code YS
300 E Street SW
Washington, DC 20460
Phone: 1-202-358-0756/0273
Fax: 1-202-358-2770
E-mail: epaylor@hq.nasa.gov
Jim Perry
Virginia Institute of Marine Sciences
Gloucester Point, Virginia 23062
Phone: 1-804-642-7182
Fax: 1-804-642-7388
E-mail: jperry@vims.edu
Liz Porter
USEPA
Mail Code 2162 OPPE '
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-6129
Fax: 1-202-260-4903
E-mail: porter.elizabeth@epamail.epa.gov
Dale Quattrochi
NASA
Marshall Space Flight Center
Global Hydrology and Climate Center
977 Explorer Blvd
Hunstville, Alabama 35806
Phone: 1-205-922-5887
Fax: 1-205-922-5723
Fax: dale.quattrochi@msfc.nasa.gov
Jon Ranson
NASA
Goddard Space Flight Center
Code 923
Greenbelt, Maryland 20771
Phone: 1-301-286-4041
Fax: 1-301-286-1757
E-mail: jon@taiga.gsfc.nasa.gov
Jerry C. Ritchie
U.S. Department of Agriculture
Agricultural Research Service Hydrology Lab
BARC-West
Building 007
Beltsville, Maryland 20705
Phone: 1-301-504-8717
Fax: 1-301-504-8931
E-mail: jritchie@hydrolab.arsusda.gov
Doreen Robb
USEPA
Mail Code 4502F
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-1906
Fax: 1-202-260-8000
E-mail: robb.doreen@epamail.epa.gov
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Alan C. Rush
USEPA
Mail Code 6301
Office of Air Quality Planning & Standards
401 M Street SW
Washington, DC 20460
Phone: 1-202-260-5575
Fax: 1-202-260-0451
E-mail: rush.alan@epamail.epa.gov
Jill Scharold
USEPA
Med 6201 Congdon Bivd
Duluth, Minnesota 55804
Phone: 1-218-720-5783
Fax:
E-mail: epajvs@du4500.dul.epa.gov
Sue Schock
USEPA
NCEA-Cincinnati, Ohio
Phone: 1-513-569-7551
Fax:
E-mail: schock@epamail.epa.gov
Gary Shelton
NASA
Code YS
300 E Street SW
Washington, DC 20546
Phone: 1-202-358-0752
Fax: 202-358-2770
E-mail: gary.shelton@hq.nasa.gov
Bob Stewart
U.S. Geological Survey
National Wetlands Research Center
700 Cajundome Boulevard
Lafayette, Louisiana 70506
Phone: 1-318-266-8501
Fax: 1-318-866-8610
E-mail: stewartb@mwrc.gov
Peter Stokely
EPA/EPIC
12201 Sunrise Valley Drive
555 National Center
Reston, Virginia 20192
Phone: 1-703-648-4292
Fax: 1-703-648-4290
E-mail: stokely.peter@epamail.epa.gov
David Stoltenberg
USEPA Region 5
Water standards & Applied Sciences Branch
77 W Jackson
Chicago, Illinois 60604
Phone: 1-312-353-5784
Fax: 1-312-886-7804
E-mail: stoltenberg.david@epamail.epa.gov
Ray Thompson
USEPA Region 1
Office of Environmental Measurement &
Evaluation
60 Westview Street
Lexington, Massachusetts 02173
Phone: 1-617-860-4372
Fax: 1-617-860-4397
E-mail: thompson.ray@epamail.epa.gov
David Toth
USEPA Region 3
841 Chestnut Bldg
Philadelphia, Pennsylvania 19107
Phone: 1-215-566-2720
Fax: 1-215-566-2782
E-mail: toth.david@epamail.epa.gov
Ramona Pelletier Travis
NASA
Building 1100
Code 5AOO
Stennis Space Center, MS 39529
Phone: 1-601-688-1910
Fax: 1-601-688-1777
R-mail: ramona.travis@ssc.nasa.gov
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Alexander J. Tuyahov
NASA
Code YS
300 E Street SW
Washington, DC 20546
Phone: 1-202-358-0250
Fax: 1-202-358-3098
E-mail: atuyahov@hq.nasa.gov
Susan Ustin
University of California, Davis
Depart, of Land, Air, and Water Resources
113 Veihmeyer Hall
Davis, California 95616
Phone: 1-916-752-0621 75092
Fax: 1-916-752-5262
E-mail: slustin@ucdavis.edu
Ming-Ying Wei
NASA
Code YS
300 E Street SW
Washington, DC 20546
Phone: 1-202-358-0771
Fax: 1-202-358-2771
E-mail: ming-ying.wei@hq.nasa.gov
Bill Wilen
U.S. Fish and Wildlife Service
4401 North Fairfax Drive
400 ARLSQ
Arlington, Virginia 22203
Phone: 1-703-358-2161
Fax: 1-703-358-2232
E-mail: bill_wilen@mail.fws.gov
Janice Wiles
University of Maryland
1420 Webster Street NW
Washington, DC 20011
Phone: 1-202-829-0346
Fax:
E-mail: wiles@cbl.cees.edu
Randolph H. Wynne
VPI and State University
Department of Forestry
Blacksburg, Virginia 24061-4024
Phone:540-231-7811
Fax: 540-231-3698
E-mail: wynne@vt.edu
James A. Yoder
NASA
Code YS
300 E Street SW
Washington, DC 20546
Phone: 1-202-358-0310
Fax:
E-mail: jyoder@hq.nasa.gov
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APPENDIX D
COMMENTS ON MONITORING NEEDS FROM EPA's REGIONAL
OFFICES
Comments were sorted into four categories that correspond with the four questions
asked in the EPA survey. These comments are identified with specific EPA Regions
when the respondent chose to include that information. In cases where the respondent
did not identify the EPA Region, that information was left blank. There have been very
few edits to the solicited responses in order to prevent any misinterpretation of the
respondents' message.
Answers to the four main questions:
1. What are the most prominent water quality problems in your area and in what
kind of water bodies are they occurring?
In Region 9, there are three kinds of important water quality issues: First, the
deterioration offish stocks and biological quality of streams because of engineered
alterations of water flows, including dams and water diversions. Second, the
eutrophication of water bodies because of sediment and nitrogen inputs from a
number of non-permitted sources, including forestry activities, agricultural
practices, and urban activities. Third, input of toxic materials and pesticides to
water bodies from a variety of sources, the largest contributors being large scale
agriculture and oil related industries. Water bodies affected are rivers and
streams, and coastal marine resources.
Almost all of the water quality problems within Region 7 are the result of
agricultural stresses. Top areas include Non-point sources-agricultural runoff;
confined animal feeding operations; agricultural-irrigation diversions (flow
reduction); agricultural-irrigation returns; point sources-TMDL's; and "Manipulated
" water systems-altered flows; reservoirs; impoundments.
Non-point source inputs from agriculture are most prominent; most importantly the
destruction of habitat and sediment loading in streams. Pesticides and herbicides
in the water column may be more of a perception than a problem. Is about to look
at some data collected as part of a REMAP project. Alteration of habitat including
siltation and channel straightening is a problem. Draining of wetlands has also
been a contributor.
The most prominent water quality problems in the north central states are:
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> In stream aquatic life habitat degradation in rivers, streams, and linear wetlands;
caused by a variety of factors, including channelization, storm water runoff, non-
point source runoff, draining of wetlands, acid mine drainage, and
impoundments.
i
> Eutrophication and sedimentation of lakes; caused by nutrients and sediments
from both point sources and non-point sources of discharge.
> Specific toxics problems in specific areas, some of which result in fish advisories.
> Great Lakes water quality issues, which involve toxic substances and air
deposition.
For the south-central US, land use information that gives greater insight into
nonpoint source pollution is the greatest general need. Precipitation and flow data
would be useful. Water temperature problems abound. Habitat structure is a
widespread problem, as is sediment. Best management practices related to
various nonpoint problems would be welcome, as would real-time data, and such
advancements as telemetry for real-time feedback on issues such as flow.
There are several areas of concern in Missouri. It depends on from what point of
view one looks for problems. In the area of domestic (private) wells. The primary
problem is bacteria. This is for the most part fecal coliform. The most direct and
perhaps least sensitive is to say that a lot of people are probably drinking out of
their septic tanks. The close second problem is nitrates. The sources are varied,
running the gamut from nitrogen fertilizer, CAFO runoff, lightning, etc, etc. The
third area of concern in private wells is fairly distant from the other two - pesticides.
While there are pesticide detections, they are few and low in concentration. Many
of the positive wells are poorly constructed creating a strong case for localized
point source contamination.
!i
There are very few problems in public drinking wells. There have been a few, low
concentration pesticide detections picked up by the Safe Drinking Water Act
monitoring. Perhaps our most widely publicized problem is in small surface water
reservoirs used as public drinking water supplies. Some of these are so small that
you can stand on the dam and see the entire watershed. In 1994 10 of these small
watersheds were given notices of violation for exceeding the atrazine MCL. Other
watersheds were very close. There were numerous other watersheds that had
detections of other pesticides. Again these were monitored through the SDWA.
New England's most common problems include: Non-point source identification
and its contributors: eutrophication problems, e.g., algae blooms, Eurasian milfoil,
expansion of eel grass beds in estuaries. Metal and toxics in fish tissues. Acid
sensitive lakes and forests - states monitor, but do not provide the resulting
88
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information. Ability to assess overall condition of forests, habitats and surrounding
water bodies. Can now break out upland versus coastal water quality; but within
the lowlands there is a need to differentiate at the sub-eco levels. Need to
separate out the impacts of high density urbanization on water quality versus the
impacts of suburban or rural areas on water quality. Need to address issues of
scale. Wetlands - need information on wetlands losses and gains by wetland type;
need to know where the losses are occurring; this information should be made
available through the permits program nationally.
Although the most obvious issues relate to surface water contamination, a major
problem is that there isn't good monitoring data to use in determining the real type
and magnitude of contamination in either surface or groundwater. All types of
water bodies have been impacted, including such rare forms as vernal pools. One
of the most widespread problems in surface water is pesticides and nitrates.
Groundwater also has nitrate problems as well as contamination by various types
of chemicals, including pesticides. Pesticides occur within both urban and rural
groundwater. Groundwater has an additional monitoring problem in that part of the
cause of a lack of quality monitoring data is due to Safe Drinking Water Act
sampling which samples mainly water supply wells and these often do not
represent the actual groundwater quality. The following list is not prioritized.
Prioritization is difficult for an entire region since different parts of the state/region
will have different "big" problems in their area:
> pesticides and nitrates in surface and groundwater (often considered nonpoint
source)
> acid mine drainage and/or metals into streams and/or rivers - can be somewhat
"localized" in that the concentrations are significantly diluted within a few miles
> pesticides and nitrates, sediment, and NPDES chemicals brought into estuaries
by rivers as well as discharged directly into the estuaries
> insufficient flows and inappropriate water temperatures for maintaining healthy
aquatic ecosystems
> siltation due to farming sediment, construction sediment, timber harvesting, etc.
> contamination of shallow groundwater by industrial chemicals emplaced by
various means
> landfill leakage into groundwater and/or surface water
> nonpoint source pollution of surface waters and bays in the urban areas, usually
via storm drains
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> contaminated sediments due to industrial and military activity found in rivers,
bays, and along the coast
i
2. Which of these are not well monitored and why?
; , |
None of the problems are monitored well enough so that the information could be
used for management and regulatory decisions that would have an influence on
water quality.
None of the above are well monitored and many are not monitored at all. The lack
of quality monitoring data on all aspects of water quality cannot be
overemphasized. The reason is simply that the funds necessary to build the
sampling infrastructure and maintain data collection over time has never been
appropriated at any governmental level, particularly on the necessary scale. The
sampling frequency is usually insufficient. Sampling locations are too few and
often based on convenience rather than optimal sites. Sampling procedures are
not uniform and the reporting of results is not standardized. Most of the older data
is not readily accessible because it is on paper or in obsolete databases and there
are no plans to translate it to electronic format or into fully relational databases.
Good spatial location information (<1 m accuracy) is rarely available so the
information cannot be readily input to a CIS.
The State is doing the monitoring (except for REMAP). There is a lack of on-the-
ground empirical data on water quality and biology (305b assessments are not
very good). Remote sensing is a good thing which might have some utility, but it is
hard to see it benefitting without available empirical data. The CWA is not very
prescriptive regarding how to monitor or the amount of monitoring which should be
conducted. More often, monitoring is not very good and some states are not
politically motivated to do this. If they do find problems, they then have to figure out
how to fix them. Remote sensing is just one of the tools to be used for monitoring.
Eutrophication is well monitored. Non-point sources and supporting land use/land
cover is not well monitored. Physical habitat is not monitored at all, except for the
collection of some biological integrity information.
Region uses databases developed and maintained by the States and USGS.
Much of the data are collected using different methods and technologies, so often
the data cannot be aggregated. They have resorted to overlaying the different
data sets within a GIS framework to define trends from the data. The Region only
collects its own data for enforcement activities. They have an interest in metals,
microbiology, pesticides, temperature, and biology.
Outside of the SDWA monitoring there is little regular monitoring of water quality.
Therefore, the worst monitoring would be in private well sector. The reason?
Funding, or the lack thereof. There is some difficulty in the public drinking
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reservoirs. While we know that there is atrazine et al applied in the watershed, and
we know there is atrazine et al in the reservoir, we don't know from which acres the
contamination really comes. We feel that if we could apply the 80/20 rule we could
solve our problem. That is, if we could work with the 20% of the acres causing
80% of the contamination, we could limit contamination with minimal impact on the
grower. There are two difficulties, lack of funding and the lack of an inexpensive
easy-to-use method to monitor the watershed to learn from where the
contamination is coming.
All of the water bodies are not well monitored. The states do very little "random"
monitoring, but rather focus almost entirely on problems. As to what data are
available for their use, RF3 data are incomplete and cannot be used;
use/attainability data are not random enough for broad projections; in short, there
are few data available for any unbiased scientific analyses. A REMAP project did
involve random sampling-quantitative analysis-only at a very large scale
(ecoregion). It was difficult to draw "regional" conclusions, as one state did not
participate in the study. There are some follow-on land cover activities planned,
however data are inconclusive to project to future "condition" scenarios.
In stream habitat conditions are not effectively monitored, due to the requirement
for voluntary efforts and other resources, and the need to contact landowners for
access. This might be a candidate for remote sensing, as represented by turbidity,
light transmissivity, or some suitable measure.
A universal problem is the lack of the ability to monitor 100% of the major surface
waters in any given State in any given 2-year 305(b) cycle. The main reason for
this is a lack of resources. If there were a way to remotely monitor waters over a
large area, with some degree of specificity, this would be of immense help to both
Federal and State agencies.
A problem has developed in the Gulf of Mexico, west of the mouth of the
Mississippi River. A large area of oxygen-deficient water has formed and has been
in place for several years. The cause of this "Gulf Hypoxia" zone has not been
fully determined, but is thought in part to be due to nitrogen loads coming down the
Mississippi River. The implication, then, is that part of the problem originates in
Region 5, but this has not been proven. A remote sensing technology would be of
benefit in determining both the extent and cause(s) of this problem.
Changes in watersheds, such as land cover, wetland loss, and soil loss are not
being effectively monitored; due to the large areas involved coupled with lack of
resources. Remote sensing could be of great benefit here.
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3. If you could reinvent water monitoring, what would you ideally like to be able
to measure?
I would match the scale of monitoring activities to the scale of the regulatory and
management decisions that affect water quality. I would put a lot of time into
developing a "distributed" monitoring and information system that combined
resources of different agencies and monitoring activities into a coordinated network
over the landscape.
In addition to an inexpensive way to know the true condition of the water quality, it
is critical to know from where the contamination is coming. With this knowledge',
resources could be narrowly focused to the problem. This would eliminate
"preaching to the choir" and over regulating those that are not causing the
problem.
Extremely accurate spatial location information for each sampling point, such that
the location would be accurate enough for use in geophysical surveys as well as
GIS and other modeling programs (<0.5 m accuracy). The ability to detect and
quantify trace concentrations of specific chemicals in all types of water bodies.
The ability to accurately measure subsurface water quality with techniques that are
easier, faster, and cheaper than monitoring wells. Perhaps too futuristic is the
development of probes that could be placed in the ground to whatever depth
needed that could take readings of water, soil/rocks, and air (vapor) compositions,
temperature, pressure, etc. and have it sent via modem, phone or whatever
directly to offices and into fully relational databases. The toxicity of the water body
to all types of life and the ability to easily trace the key toxic component.
The simple collection of quality data isn't enough. The data should be collected in
a format that is easily loaded into a fully relational database and GIS coverages
routinely made. The data should be easily accessible so that GIS coverages,
comparisons and interpretations can be made via computer graphics and
programs at the staff level. The creation of GIS coverages should be automated.
Reinvention should follow a REMAP sampling regime, but with more funding to
support more intensive sampling. Bring to bear available remote sensing tools and
products to determine which sensors are reliable (confidence/statistical) for which
levels of detail. Charcoal kilns in southwest Missouri and particulate matter
emissions (P10) are a current problem. Current "manual" monitors overload
almost immediately, and a sensor could provide good data (if available) for these
high levels. Of course no legislation exists to deal with the issue.
A national monitoring program; a framework to consistently assess water quality in
terms of chemical and biological integrity. Need more work on condition
measurements.
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Would like EPA first to be more prescriptive regarding a minimum level of
monitoring; requirements for monitoring should be made stringent; for example, a
certain percentage of a state must be monitored; certain kinds of data should be
collected with specific quality assurance requirements. Need more dedicated
resources to do monitoring. Monitoring is not well coordinated; must examine how
data are/should be collected, and EPA should be the catalyst to make the
coordinated monitoring happen. Note: a comment related to this - a fear that
people using, for example, GIS, will go out and gather data collected from various
sources using various methods, and will not understand or be able to properly
assess the quality of the data they are using.
Biological assessments should be expanded and refined, and moved to the realm
of remote sensing if possible.
Chemical and physical monitoring should be moved into the realm of remote
sensing, if possible (as opposed to field sampling and lab analyses). This would
increase the feasible area of assessment, and also decrease manpower
requirements for monitoring.
Field and lab methods should be improved and made more cost-effective,
especially for organics and metals.
Remote sensing would be a good way to track wetlands loss (or gain), one of the
proposed environmental assessment indicators.
If possible, remote sensing should be used to track Great Lakes water quality
issues.
If possible, remote sensing should be used to assist in watershed management, to
address issues such as land cover, rain event impacts, and soil loss sediment
loads in streams.
4. What are your ideas of "condition" in watersheds and water bodies, and how
would you measure this?
I would adopt a multi-metric indexing system, based on econometric statistics.
This is the method that was adopted by the EPA Rapid Bioassessment Program,
and it could be developed and improved in significant ways.
There are insufficient data of adequate quantity and quality to really evaluate the
health of most systems.
Region 7 does nothing like that now. They are working with their states through
GAP to develop broad-scale vegetation classification maps (greenness ratios) to
assess areas of high water quality. And they are utilizing more land cover data to
approach assessments of condition, but are a far ways off. They have recently
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been asked by their RA to provide a briefing of their regional remote sensing
capabilities...not EPA, but rather "local" centers of expertise within the region.
i
Databases dealing with chemistry and microbiology are not enough to address the
problems...a strong biological component is also needed...perhaps something like
an index of biological integrity. He gives strong support to holistic ecosystem
approaches to addressing the problems in water, as they need quicker ways to
develop and project status and trend for water bodies. Relative to NASA
technologies, he very much supports continuation of remote sensing methods for
land use/land cover changes over time, especially if the technologies could include
a measure of animal counts (density).
The condition of Region 5 water bodies can best be described in terms of the
latest 305(b) water quality assessment reports, which show that, on the average,
for rivers and streams, 66% of waters assessed were "good" (fully supporting or
threatened for aquatic life use); and 34% were "fair to poor" (partially or non-
supporting for aquatic life use). These figures are averages for the six States for
1994. The 1996 figures are not yet available. It should be noted that the 1994
assessments were based on only 23% of the total miles of rivers and streams in
Region 5 (75,350 out of a total 324,000 mi.). Hopefully, by using advanced remote
sensing techniques, the percentage of waters assessed could be significantly
increased.
i
Ecological condition; the assemblages that we can identify and indicators to let us
know when change is occurring and the causes of these changes; also linking
rates of change and causes; e.g., fish assemblages and macroinvertebrates may
not be the best indicators; a good indicator might be algae blooms; what are the
indicators? Toxics - not only fish contamination but how the toxic pollutant is being
transferred throughout the ecosystem; e.g., mercury - where is it coming from and
how is it transferred; are there certain environmental conditions which cause higher
levels of mercury in fish? Need to distinguish between natural causes and man-
made causes, and be able to modify our behavior/actions to reduce/eliminate the
impact of man-made causes. Need an easy method to measure pesticides
residues in aquatic environments; now they cannot measure residues because
they are short-lived; and the causes are not known.
Other general answers and recommendations:
The most prominent water quality problems are non-point source related...
temperature, sedimentation in streams and rivers. In agricultural areas, nutrients
are another issue. These parameters are currently not well monitored, due to
insufficient funds. Data are usually obtained from states or other federal agencies.
The only database used routinely is STORET, however data are not current. A
USGS Home page has much more current data, but there are concerns about the
quality/reliability of that data. The issue may not be one of requiring new
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technologies for monitoring, but rather using technologies that currently exist. If
new technologies are cheaper, faster, more fieldable...and result in better, current
data bases, then people will support their development/applications. Needs
include having access to data for, temperature, sedimentation, nutrients, etc.
Condition assessment would include holistic integration of biological, chemical, and
physical parameters. Some parts of the region are attempting watershed analyses
using this approach (TFW monitoring), however they still focus inordinately on
habitat issues (no chemical). They currently use remote sensing imagery in CIS
maps to identify forested land, soil types, and vegetation types.
The 1994 National Report identifies the number one cause of impairment in
streams as bacteria. Yet, I still feel that the impairments due to bacteria are under-
reported. There many reasons why this pollutant is under-reported including a 6
hour holding time on the sample preservation, representativeness of a bacteria
sample, and a 48 hour processing time from sample collection to quantification. I
find it amazing that we take a sample a water body, let people swim in it for 48
hours, and then decided to close a beach due to potential human health threats
from bacteria identified in a sample that was collected 48 hours earlier. We need a
better method. The FDA has been working on a instantaneous bacteria sample for
E. coli in meat products. Perhaps we could build on that and come up with an
instantaneous process for our beaches. The second biggest problem, again
according to the 305b Report, is siltation. This is a problem that NASA may be able
to assist in monitoring and identifying sources using remote sensing. This could be
done by identifying areas where heavy erosion is occurring. We could also expand
this parameter to examine areas of habitat modification using parameters such as
erosion, temperature, channelization, and others. The NASA information could
help identify areas were BMPs are most needed. Lastly, and more of Regional
concern, is abandon mine drainage and acid deposition. Abandon mine drainage
is the single largest source of impairment of aquatic life use in Region III.
Approximately, 5,000 miles are impaired in R3 due to this pollutant. We feel that
this is under-reported. Could NASA help identify other streams impaired across
the Region? Can pH be monitored remotely? Is there another indicator that can be
used? What about acid deposition from air pollution? Many of our states do not
recognize acid deposition as a major problem. Some of our Regional Data have
indicated that there is significant impacts on first order streams that are not
routinely monitored by the states. Could NASA help identify impacted streams?
It appears to me, though a novice in this area still, that in a State like New York
there are just too many water bodies to assess and that may be their biggest
problem RE monitoring. NY indicates to me that because they can't assess more
of the water bodies, they can't depict the percentage that support designated use
or impacted by agriculture (for instance) accurately. Therefore, what tech. or
application thereof could assess MORE water bodies w/ the same amount of State
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resources? I also get the impression that NFS pollution is not measured
adequately enough and possibly not in enough areas.
There are several important indicators to an effective water quality/ecological
assessment for both terrestrial aquatic and marine environments.
Marine/estuarine/lacustrine environments are classified as terminal systems, where
water/sediment/pollutants (stressors) are transported into and stored. In the larger
systems mixing occurs allowing for longer time periods before a problem is
identified. Certain habitats and biota are indicators of these stressors. Therefore,
it is important to identify the ecological habitats within a particular
watershed/lake/estuary/coastal system. To do this identification remote sensing is
the ideal methodology for the classification of habitats. With recent advancements
in marine acoustics high-resolution swath mapping provides an ideal mechanism
for determining ecological habitats within marine/estuarine/lacustrine
environments.
i
Data collected in a high-resolution swath mapping survey are backscatter and
bathymetry at sub-meter scale. With the collection of the high-resolution
bathymetry (DEM) the backscatter data can be scientifically visualized in
three-dimensions for better identification of habitats. At present there does not
exist a classification scheme for identifying habitats using acoustic backscatter
data. I am in the middle of writing a proposal to the USGS and the University of
New Brunswick, Canada, to develop a classification scheme for the identification of
sea floor/lake bottom sediment types and environmental habitats. If I were to
reinvent monitoring, I would like to improve the use of satellite and acoustic
remotely sensed data for fluvial/marine/estuarine/lacustrine systems. Especially
were stream/lake and stream/estuarine/marine systems come together. Is there a
means in which we can join forces to identify resources to further the advancement
and use of remotely sensed data? My philosophy is the collection of sediment,
water, physical habitat and biotics is to ground truth the remotely sensed data,
which in turn greatly enhances the analyses and interpretation of the sampling
data.
Bacteria/pathogen indicators. We need better bacteria and pathogen indicators
that are good indicators of human health threat, and also allows us to distinguish
sources (e.g., wastewater vs. natural vs. animal waste, etc.). Some of our States
are continuing to look for better pathogenic and bacteriological indicators. Often,
the indicators (e.g., Enterococcus) do not correlate well with disease susceptibility
and human health threat. Also, sometimes the indicators do not necessarily reflect
anthropogenic sources. Source identification is important so that the right control
measures can be placed. (See also #2 below) 2. Molecular markers for source
identification. As we move away from emphasis on point source controls and more
toward nonpoint sources, it becomes more important to distinguish other sources
of pollution (storm water runoff, other nonpoint sources). Some work has been
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done on markers such as linear alkylbenzenes (LABs), but other markers that help
us distinguish between the various anthropogenic sources would be extremely
helpful. This information would assist us in identifying the nonpoint source so that
appropriate control strategies can be implemented. 3. Rapid and/or easy coral
reef assessment. Many of our tropical States need a quick and easy way to
establish baseline and assess long-term health of their coral reef ecosystem. It is
difficult for our outer Pacific Islands to collect intensive monitoring information for
coral reefs. However, certain physical parameters like nutrients, sea surface
temperature, etc. may be collected long-term that provides long-term historical
trends of important or limiting coral reef health parameters.
My responsibilities include providing direction on emerging monitoring and
information management technologies for an Interagency Program monitoring the
ecological health of the San Francisco Bay estuary. I would like to briefly point out
some of my experience from the over 40 monitoring elements of IEP. 1.) "Real
time" bio monitoring needs. If you would like a real life demo I'd be happy to show
you what we have on-line with IEP on one of our home pages. This is real time
bio-monitoring, uploaded daily from boat to data scrub to edit checks to data base
to WWW home page to GIS maps. 2.) Geo-positioning data needs. GPS, Loran-C,
interactive data entry via GIS software such as ArcView E.g., some city storm
water programs have voice activated systems installed in mobile units. 3.) New
instrumentation for chemical and physical parameters. Real time monitoring needs
require new instrumentation for chemical and physical parameters. My division at
USBR has several data loggers with GPS time stamp, Loran C connected on a
boat. We use wonderware as the software (I believe) which combines the data
stream each second from all sensors and puts it into storage.
Need to analyze the annual variation in Normalized Vegetation Difference Index
(NDVI) values along the south Texas coast, relate those changes to climatic
events (I.e. periods of drought) and examine associations with changes in coastal
condition (e.g. salinity variations). The second project involves 3 phases: a) the
development of physiological indices of health for wetland plants, b) the
association of these indices with the aircraft collected spectral signatures of
wetlands, and c) the large scale mapping of wetland health based on their
reflectance/irradiance character. AED is also a participant in a study, with remote
sensing scientists at Brown Univ. and the Graduate of School of Oceanography at
the Univ. of Rhode Island, to apply aircraft and satellite technology to monitor
selected parameters in the waters of Narragansett Bay.
Regardless of the type of monitoring, it is critical to have highly accurate (<0.5 m)
vertical and lateral elevation/location information for each sample location to
ensure that the collected data can be used by many different techniques and
purposes.
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APPENDIX E
ACRONYMS
ADEOS - Advanced Earth Observing Satellite
ASTER - Advanced Spaceborne Thermal Emission and Reflection Radiometer
AVHRR - Advanced High Resolution Radiometer
AVIRIS - Airborne Visible InfraRed Imaging Spectrometer
CWA-Clean Water Act
DEM - Digital Elevation Model
DOC - Dissolved Organic Carbon
EOS - Earth Observing System
EPA - Environmental Protection Agency
ERS - European Remote Sensing Satellite
EROS - Earth Resources Observing System
ESE - Earth Science Enterprise
ETM - Enhanced Thematic Mapper (see TM) (aboard Landsat 7)
GIS - Geographic Information System
GPS - Global Positioning System
GOES - Geostationary Operational Environmental Satellites
HUC - Hydrologic Unit Code
IWI - Index of Watershed Indicators
LAI-Leaf Area Index
LIDAR - Light Detecting And Ranging
MASTER - MODIS - ASTER Simulator
MODIS - Moderate Resolution Imaging Spectrometer
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MSS - Multi Spectral Scanner, has a visible/near infrared/thermal radiometer
MTPE - Mission to Planet Earth
NASA - National Aeronautics and Space Administration
NEXRAD - Next Generation Radar
NDVI - Normalized Difference Vegetation Index
NOAA - National Oceanic and Atmospheric Administration
NFS - Non Point Source - pollution
NSCAT - NASA Scatterometer
NWI - National Wetlands Inventory
OCTS - Ocean Color and Temperature Scanner
OGWD - Office of Ground Water and Drinking Water
ORD - Office of Research and Development
OWOW - Office of Wetlands, Oceans and Watersheds
PPM - Parts per Million
SAR - Synthetic Aperture Radar
SeaWiFS - Sea-viewing Wide Field of view Sensor
SIR - Shuttle Imaging Radar
SPOT - (Systeme Probatoire d'Observation de la Terre) European satellite
SRTM - Shuttle Radar Topography Mission
SS/MI - Special Sensor Microwave Imager
TIMS - Thermal Infrared Multispectral Scanner
i
TM - Thematic Mapper visible/near infrared/thermal radiometer (aboard Landsat 4 and 5)
TMDL - Total Maximum Daily Loads
TMI - TRMM Microwave Imager
TRMM - Tropical Rainfall Measuring Mission
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TSS - Total Suspended Solids
USGS - United States Geological Survey
WSR-88D - Weather Surveillance Radar - Doppler
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