To:
Tiered Aquatic Life Use Workgroup
From:
Susan Jackson 11/5/01
U.S. EPA Biological Criteria Program
Re:
Revised Biological Condition Gradient
Attached is the latest version of the draft biological condition gradient - revised to address
written comments from individual workgroup members and specific recommendations from the
workshop in Baltimore last winter. Your review and comment on the revised biological
condition gradient is requested by December 16, 2001. Please email me with a cc to
Dennis McIntyre. You can also pen your comments in the margins of draft documents
and mail them to me at: U.S. EPA, mail code 4304, 1200 Pennsylvania Avenue, Washington
D.C. S.W, 20460. Your comments will be key in setting the agenda for the next workgroup
meeting planned for March, 2002 in the Baltimore-Washington area. The dates for the
workshop are not yet set.
Right up front, I want to acknowledge Susan Davies for her leadership and dedication to this
effort. Additionally, several workgroup members have provided extensive review and comment
on the revisions, including extremely insightful recommendations for tackling tough issues.
These workgroup members include: Susan Norton, Phil Larsen, Bob Hughes, Jan Stevenson,
Mike Barbour, Maggie Passmore, Dave Lenat, Chris Yoder, Dave Courtemanch, Russ
Frydenborg, Ed Hammer and Evan Horning. Additionally, Bill Wuerthele from Region 8 water
Quality Standards Program and LeRoy Poff from Colorado State University have provided
insightful comments and different perspectives on the draft materials.
Biological Condition Gradient - File Index:
Based on the workgroup meeting in Baltimore last year, the draft biological condition gradient
has been revised in both substance and format. What you will notice first is that there are now
several files attached to this email. These documents are in Word and are explained in the text
that follows. These files are:
1. the revised biological condition gradient - file: biologicalconditiongradient
2. narrative summary of the biological condition gradient - file: executivesummary
3. attribute matrix - file: attributematrix
4. background explanation on attributes from Susan Davies - file: attributeexplanation
5. Maine case example - file: mainecaseexample
6.
draft definitions - file: definitions
These files are discussed below. Redesign of the workgroup website has not been completed
yet. In the interim, you can access workshop summary notes and presentations at the following
website: http://www.glec_online.com/test/alus2/alus2.htm. Contact Dennis McIntyre (614)
487-1040 if you have trouble accessing the website.
Key Baltimore Workshop Recommendations on Draft Biological Condition Gradient:
There were many specific technical edits and substantive comments from individual workgroup
members and from the workshop recommendations. To the best extent possible, these technical
edits and comments have been incorporated in the current draft. Not all comments may have
been incorporated and some of these comments are discussed below under “outstanding issues”
and remain to be resolved. The main changes to the biological condition axis are discussed
below.
#1. Simplify the biological condition gradient but do not lose the detail. There was a strong
consensus at the workshop that a simplified framework is needed to provide a more systematic
approach to characterizing predicted biological change along the gradient. This is important for
both technical readers (e.g. field biologists) and for managers who need to know how this
framework will fit into and benefit their programs (e.g. water and watershed program managers).
At the Baltimore workshop, the NW Breakout group produced a simplified model for organizing
the biological condition gradient. This framework was the basis for the reorganized format of
the biological condition gradient, the attribute matrix and the resulting executive summary.
The file attribute explanation provides an interpretative context for the attributes in the
biological condition gradient. Additionally, a management framework that links the biological
condition gradient to water quality standards is in draft and will be distributed to the workgroup
next month. See discussion below under “Work in Progress.” The original case example for
Northern temperate streams is now a separate file, maineexample. Additional case examples
representative of different regions will be developed this spring once the condition gradient has
undergone this second round of review and comment.
#2. Even out the magnitude of change in each tier. Another major workshop comment was
the uneveness in change from one tier to another in the original condition gradient. Specifically,
the original top two tiers (formally Tiers A and B) were seen as “too tight” and viewed as
clustered at the high end of the gradient - difficult to distinquish between the two, particularly for
management purposes. The third tier, (formally Tier C) covered too broad a range of change
between the high end of the gradient and the lower two tiers representive of waters in poor
condition (formerly Tiers D and E). Attention and more detail was put to this part of the
condition gradient - the range of biological conditions between “very good” and “poor.”
The condition gradient was revised to address this concern about uneveness in the tiers. The
revised gradient now has 6 tiers identified by numbers 1 through 6 (letters were dropped because
of association with letter grades). Tiers 1 and 2 should equate with the CWA integrity
objective (see outstanding issues discussion below). Tiers 3 and 4 were developed based on
consensus workshop recommendations on what constitutes conditions that meet the CWA goal
for protection and propagation of fish, shellfish and wildlife - the “interim goal.” The intention
of this revision has been to describe Tier 4 to be not significantly different from the former Tier
C biological condition, as agreed upon in Baltimore. The lower two tiers, 5 and 6, represent
conditions that do not meet the interim goal.
#3. Evaluate attainment of the CWA interim goal (protection and propagation of fish, shellfish
and wildlife) to include maintenance of ecosystem function. There was broad support at the
Baltimore workshop that an ecological benchmark for attaining the interim goal for aquatic life
was maintenance of ecosystem function. The revision incorporates this recommendation but
further work is needed to clarify what we are really thinking about here. Currently, State and
Tribal programs are commonly using methods that measure community structure. Information
derived from these measures is then used as surrogates for inferring ecosystem function.
Additionally, teasing out issues of different scale is also a challenge. The workgroup is requested
to review and provide specific comments on how this attribute can be currently measured;
strengths and limitations of any particular method, and pitfalls to avoid. Please refer to the file
attribute explanation for further discussion.
#4. Clarify terminology and provide definitions. Please review and comment on definitions
file. The definition of terms on taxa is context dependent and will ultimately be user defined
(e.g. ecoregion, stressor, sampling method, level of effort i.e. species vs family identification).
For example, the taxa that can be described as sensitive or tolerant will differ depending upon
stressor. Assemblages may have seemingly contradictory responses depending on the stressor
scenario.
Thank you to Dave Courtemanch, Chuck Hawkins and Bob Hughes for contributing definitions.
Also, Doug Norton from the EPA’s watershed program authored an EPA white paper on
non-native species. Definitions from that paper have been included.
Outstanding Issues:
#1. Presence of Non-native species in the highest tier (tier 1). Tier 1 represents “natural”
condition; that is “native structural, functional and taxonomic integrity is preserved”. As
currently drafted, the tier also allows for the presence of non-native species that have no
detrimental effect on native species and where, conceptually, native structure, function and taxa
are not altered. The reason for this is practical - review comments from some workgroup
members strongly recommend making tier 1 an attainable management goal for this gradient to
be fully relevant and implementable in State and Tribal water quality programs. Providing legal
protection for very high quality waters that would be considered pristine except for the
ubiquitous presence of an intentionally introduced species, typically a fish such as brown or
rainbow trout, is considered desirable.
On the other hand, some other workgroup members have recommended that the top tier remain
“pure” and not allow for the presence of any non-native species. The arguement for this
position is equally valid. While recognizing the hypothetical nature of this tier for most if not
all parts of the world, a clean definition, or standard, provides a conceptual anchor for the
biological condition gradient that is not compromised.
#2. Making Allowance for Global Extinctions in Tiers 1 and 2. On a similar vein, the current
tiers 1 and 2 also allow for global extinction. Again, the basis for this is primarily practical - to
provide legal protection for waters that would be considered pristine or near pristine except for
the absence of a globally extinct species.
There is not a right or wrong position on the above issues and workgroup consensus may not be
achievable. You are requested to comment on these two related issues, and, if possible, include
examples that demonstrate key points of your arguement. If a workgroup consensus cannot be
achieved, stating the case for each option is the next step and will be important information to
enable the U.S. EPA make a determination. Ultimately, it is important to clearly communicate
what this gradient is and the underlying rational, so that State and Tribal water programs,
stakeholders and the public clearly understand its strengths and limitations.
#3. Tiers that do not attain the CWA interim goal for aquatic life. Most of the workgroup
discussion to date has focused on characterizing the biological condition tiers that attain the
CWA interim goal for aquatic life, “the protection and propagation of fish, shellfish, and
wildlife”. This tendency is a natural progression - moving our attention from the high end of the
gradient on down the scale. Several workgroup members have identified the need to provide
more definition, perhaps an additional tier, to the part of the gradient that does not meet the
interim goal. This is a practical need for those States and Tribes where degradation due to
human activities is severe and widespread. Incremental, attainable goals for restoring highly
degraded waters are needed. Even if these goals do not meet the CWA interim goal - they are
steps in the right direction. The current lowest tier, tier 6, is seen as dead and not useful as a
management goal. Over the next few months, there will be a focused effort on drafting
revisions to tiers 5 and 6. If you would like to be part of a focus group to prepare a draft for the
full workgroup - please email me.
Key Messages That Need To Be Communicated Loud And Clear:
Effective communication is a priority need - a clear, consistent message about what the gradient
is and what it is not, how it is to be applied, and how to minimize, if not totally avoid,
misunderstandings and misapplications. Your review and comment on communication (e.g.
specific terms that may be misinterpreted, jargon, sweeping generalizations or terms that may
have multiple meanings) is requested. So far, the following key communication themes that
have been identified:
1. The biological condition gradient is conceptual. The purpose of this national
framework is to provide an ecologically-based model for communication of biological condition.
The descriptive, incremental gradient should enable better communication about where goals
could be set and enable a better, more accurate understanding of current conditions. This
should result in more meaningful engagement of the public in goal setting - specifically in the
designation of aquatic life uses in State and Trial water quality standards programs.
2. The conceptual framework is not defined by any one method. The conceptual gradient
is independent of different assessment methodologies (i.e. Rapid Biological Assessment, Index
of Biological Integrity; RIVPACS, etc.). The ecological premise that supports the model should
reflect the same ecological basis that underlies all the methods used to quantify predicted
biological response to increasing human disturbance. Examples of how different
methodological approaches can be applied to this framework will be prepared in next steps upon
completion of this round of review and comment.
3. Number of tiers. The purpose of the number of tiers is to provide a highly resolved
conceptual biological condition gradient. There is no expectation that State or Tribal programs
adopt 6 tiers, or categories, of designated uses. While step wise progress toward refinement of
designated aquatic life uses in State and Tribal water quality standards programs is desired over
the long term, the ultimate number and type of levels of protection is a State or Tribal
determination.
4. The attributes are not a checklist. The list of attributes is intended to organize and record
the current state of our understanding and observations concerning changes in key characteristics
of an aquatic community in response to increasing levels of human disturbance, but it should not
be thought of as a checklist or scorecard. Rather the approach should be thought of as seeking
to identify a “best fit” tier, weighing the importance and signal-strength of the different attributes
as they pertain to a specific waterbody. The listed attributes generally have a quantifiable
aspect that potentially be measured in many different ways. This conceptual model in no way
reduces the necessity of ultimately developing rigorous methods for the quantitative and
statistical validation of relative biological conditions. Comments and recommendations from
the workgroup on such an approach is requested.
Work In Progress:
1. Implementation in State and Tribal Water Quality Standards. A draft management
matrix relating the biological condition gradient to chemical water quality criteria and the water
quality standards program is currently under review by EPA’s water quality standards program.
This draft is based on the example provided by Rich Eskin at the Baltimore workshop. A draft
will be distributed to the workgroup within a month. This matrix will provide the starting point
for drafting program guidance to implement the conceptual framework in water quality
standards. Specific discussions are occurring within the criteria and standards program on the
following:
The relationship between other types of water quality criteria (e.g. chemical, nutrient) and both
the biological condition and human disturbance gradients is also being examined. Members of
the Tiered ALU workgroup are engaging scientists from EPA’s chemical and nutrient water
quality criteria program and research laboratories to work through theses issues. Products from
this effort will include case examples of how other types of water quality criteria fit into both
gradients and will be prepared for the workgroup distribution prior to the workshop planned for
March.
Additionally, the Water Quality Standards Program is engaged in discussion on the application
of the tiered aquatic life framework to use attainability analysis (UAA). A workshop is planned
this week in San Francisco on current approaches and issues in conducting use attainability
analyses. The tiered aquatic life use model will be included in the workshop discussions and
option development. Chris Yoder will be attending the workshop with Jim Keating of EPA’s
Water Quality Standards Program.
2. Additional Case Examples. Two workshops are planned for next spring to further
groundtruth the biological condition gradient and to develop additional case examples for
streams in the central plains and the arid west. These workshops will be modeled after the data
exercises conducted at the Baltimore workshop last year. EPA’s nutrient criteria team intends to
send scientists to these workshops to help internally link our two efforts. Additionally,
preliminary plans are in the works to “road test” the conceptual framework and develop case
examples for large rivers based on the Ohio and the Upper Mississippi Rivers; for depressional
and riparian wetlands; and for estuaries based on Narragansett Bay National Estuary Program.
We welcome suggestions from the workgroup for other opportunities or needs for other case
examples.
3. Human Disturbance Gradient.
A human disturbance gradient has been drafted by Bob Hughes with support from the steering
committee. The human disturbance gradient describes conditions in the environment that range
from natural to severely degraded. It is similar in structure to the biological condition gradient in
that it is divided into a set of tiers with each tier containing a narrative description of water
resource variables and the human activities that affect the water resource variables. Examples
of the water resource variables are, habitat structure, flow regime, water quality, toxic chemicals,
energy source and biotic interactions. The human activities that affect these water resource
variables are landscape character, riparian condition, barriers and channel morphology. A focus
of the next general workgroup meeting will be to groundtruth the human disturbance gradient in
a similar fashion to the biological condition gradient at the Baltimore workshop. A draft will be
distributed to the workgroup for review and comment prior to the next workshop. Target date
for completion of the draft for workgroup review is January.
4. Linkage of Conceptual Framework to Technical Components. A next important step
will be to illustrate how the conceptual model can be implemented in existing State or Tribal
programs; including State programs that may not yet have a comprehensive monitoring program,
long term data base or programs that rely on Family-level taxonomic information. Examples
will include different methodological approaches and different levels of assessment effort. This
information will be an important component of national guidance.
5. Timeframe for completion of workgroup activities. At our first workgroup meeting in
June, 2000, the workgroup was charged with developing recommendations on how to use
biological assessments and criteria to tier designated aquatic life uses in State and Tribal water
quality standards; identify obstacles and pitfalls to avoid; problem solve these issues and develop
solutions. Workgroup recommendations will be used by the U.S. EPA to develop national
guidance. The workgroup made recommendations on the elements of a tiered aquatic life use
approach and the basic outline of a conceptual biological condition gradient at the first
workshop. At our second workgroup meeting last February, a draft biological condition
gradient was evaluated with the attached revisions as a result. Another major component of the
framework, the human disturbance gradient, was introduced and is being prepared for
distribution to the workgroup this winter. Additional components of the guidance that are in
preliminary stages include a management framework and case examples that link the conceptual
model to technical methods and program implementation. The third workgroup meeting,
proposed for March 2002, will finalize the biological condition gradient; groundtruth the draft
human disturbance gradient and management framework. I anticipate one additional workgroup
meeting either in the Fall of 2002 or Spring of 2003 to finalize the human disturbance gradient,
management framework and case examples. We are currently preparing our workplans and
budget for FY2002 which will influence the time for completion of workgroup products.
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