United States       Office of Science and Technology  August 1991
         Environmental Protection   Office of Water
         Agency	Washington. P.O. 20460	

              George R. Gibson, Jr.
         Coordinator, Biological Criteria Program
                Office of Water
         U.S. Environmental Protection Agency
                Washington, DC
                 August 1991

Purpose  of this  Paper
    The Biological Criteria Program was initiated by EPA in response to re-
    search and interest generated over the last several years by Agency, State,
and academic investigators. This interest has been documented in several re-
ports and conference proceedings that were the basis for creation of the  pro-
gram and for the preparation of Biological Criteria National Program Guidance for
Surface Waters  (U.S. Environ. Prot. Agency,  1990). The overall concept  and
"narrative biological criteria" are described in that guide.
   Because establishing narrative criteria is an important first step in the  pro-
cess, the material that follows here is intended to be an elaboration upon and
clarification of  the term narrative biological criteria as used in the guide.  The
emphasis here  is on a practical, applied  approach with particular attention to
cost considerations and the need to introduce the material to readers who may
not be familiar with the program.
Introduction  and  Background

    Biological monitoring assessment and the resultant biological criteria rep-
    resent the current and increasingly sophisticated process of an evolving
water quality measurement technology. This process spans almost 200 years in
North America and the entire 20 years of USEPA responsibility.
   The initial efforts in the 1700's to monitor and respond to human impacts
on watercourses were based on physical observations of sediments and debris
discharged by towns,  commercial operations, and ships in port (Capper, et al.
   Later, chemical analyses were developed to measure less directly observ-
able events. With industrialization, increasing technology, and land develop-
ment pressures, both types of monitoring were incorporated into the body of
our State and Federal public health and environmental legislation.
   Valuable as these methods were, early investigations and compliance with
water quality standards relied primarily on water column measurements re-
flecting only conditions at a given time of sampling. Investigators and manag-
ers have long recognized this limitation and have used sampling of resident
organisms in the streams, rivers, lakes, or estuaries to enhance  their under-
standing of water resource quality over a greater span of time. During the past
20 years, this technique has become increasingly reliable and is now a neces-
sary adjunct to the established physical and chemical measures  of water re-
sources quality.
   USEPA has therefore concluded that biological assessment and consequent
biological criteria are an appropriate and valuable complement to the Nation's
surface water management programs. This added approach not only expands
and refines this management, it is also consistent with the country's growing
concern that the environment must be protected and managed for more than
the legitimate interests of human health and welfare. The protection of healthy
ecosystems must be part of our responsibility and  is indeed  related  to our
welfare. Fish, shellfish, wildlife, and  other indigenous  flora and fauna of our
surface waters require protection as  intrinsic components of the natural sys-

    A carefully completed survey and subsequent assessment of these resident
organisms in relatively undisturbed areas reveal not only the character or "bi-
ological integrity" of a natural, healthy waterbody, they also provide a bench-
mark against which similar systems may be compared where degradation is
suspected. Biological measurements also help record waterbody changes over
time with less potential temporal variation than physical  or  chemical ap-
proaches to water quality measurement.
    This biological element of water resource evaluation is being introduced
by EPA in a stepwise fashion. First, narrative biological criteria will be insti-
tuted by the States by the end of 1993. Later, with sufficient narrative experi-
ence, numeric criteria incorporating quantitative values will be adopted. This
will allow for systematic adjustments and refinements of methods by both the
Agency and the States.
Narrative  Biological  Criteria

    The first phase of the program is the development of "narrative biological
    criteria". These are essentially statements of intent incorporated in State
water iaws to formally consider the fate and status of aquatic biological com-
munities. Officially stated, biological criteria are "... numerical values or nar-
rative expressions that describe  the reference biological  integrity of aquatic
communities inhabiting waters of a given designated aquatic life use" (U.S.
Environ. Prot. Agency, 1990).
    While  a narrative criterion does not stipulate that numerical indices or
other  population parameters be  used  to indicate a particular level of water
quality, it does rely upon the use of standard measures and data analyses to
make  qualitative determinations of the resident communities.
    The State, Territory, or Reservation should not only carefully compose the
narrative biological criteria statement but should also include an indication of
just how its application is to be accomplished. The determination of text {how
the narrative biological  criteria  are v/ritten) and measurement procedures
(how  the criteria will be used) is up to the individual States in consultation
with EPA. Some degree of standardization among States sharing common re-
gions  and waters will be in their best interests. This regional coordination and
cooperation could  help  improve efficiency,  reduce costs, and expand the
database available to each State  so that management determinations can be
made  with greater certainty.

Attributes of A Sound Narrative Criteria Statement

    States should require that it:

    1.  Support the goals of the Clean Water Act to protect a balanced
      indigenous population of fish, shellfish and wildlife;

    2.  Include specific aquatic, marine, and esruarine community
      characteristics that must be present for the waterbody to meet a
      particular designated use;

    3.  Include characteristics that are quantifiable and written to protect and
      or enhance the designated  use;

    4.  Protect the most natural community possible; and

    5.  Avoid potentially conflicting standards by emphasizing the protection
       of sensitive, natural systems and the independent application of
       existing and future codes or regulations. In no case should degradation
       of the waters be authorized.
An Example of A Narrative  Biocriteria Statement

    The intent of the State is to preserve, protect, and restore the water re-
sources of [name of State] in their most natural condition. The condition of
these waterbodies shall be determined from the combined measures of physi-
cal, chemical, and biological characteristics of each surface waterbody type, ac-
cording to its use  attainability classification ... [as previously  identified
according to the Clean Water Act, Section 305 (b)]... As a component of these
measurements, the biological quality  of any given water system shall be as-
sessed by comparison to a reference source(s) of similar hydrologic and water-
shed characteristics that  represent the  optimum natural  condition for  that
    Such reference sources or reaches of water courses shall be those observed
to support the greatest variety and abundance of aquatic life in the region as is
expected to be or has been historically found in natural settings essentially un-
disturbed or least disturbed by human impacts,  development, or discharges.
This condition shall be determined by consistent sampling and reliable mea-
sures of selected indicative communities of flora  and/or fauna as established
by ... [appropriate State  agency or agencies] . . . and in conjunction with ac-
ceptable  chemical, physical, and  microbial  water quality measurements  and
records judged to be appropriate to this purpose.
    Management efforts relative to these criteria shall be consistent with the
objective of restoring  and protecting natural communities of fish, shellfish,
and wildlife appropriate to these waters and in all cases shall protect against
degradation of the  highest existing or subsequently obtained water quality
    Because separate parameters are involved, no physical, chemical, or  bio-
logical criteria or regulations implemented for the protection of these waters
shall be deemed superior  to another in application or enforcement.
Data Gathering to Establish and Support Narrative
Biological Criteria

    A State need not specifically list in the narrative statement the sampling
procedures and parameters to be employed, but it should indicate and charge
the appropriate administrative authority with this responsibility as indicated
parenthetically above.
    The selection and sampling process, certainly at the outset, should be sim-
ple, reliable, and cost effective. There is no limitation on the sophistication or
rigor of a State's procedures. In many instances, a State may choose to create
procedures and regulations more complex and complete than are indicated
here, however a basic design and methodology to consider should include the
following elements:

    '  1. Resource Inventory, A field review of State water resource condi-
tions and a first hand documentation of the status of water quality relative to
the use designation categories are essential. Management planning should not
be done independent of the biologists, water resource managers and chemists
directly involved with the resource base. They should be the primary partici-
pants from the outset.

    •  2. Specific Objective* and Sampling Design. States will need to de-
sign a system identifying "natural, unimpacted" reference sources appropriate
to each surface waterbody type in each of the designated use categories in the
State (e.g., streams, lakes and reservoirs, rivers, wetlands, estuaries and coastal
waters) and the use categories (see example, Page 8) for each grouping of
these waterbody types. Sources for defining reference condition may include
historical data sets, screening surveys, or a consensus of experts in the region
of interest.
    Because natural water courses do not always follow political boundaries,
the most effective  approach may be  a joint or group effort between two or
more States. Where this coordination  and cooperation is possible, it may pro-
duce a superior database  at less cost  than any individual State effort. EPA is
working through its regional offices to assist in the development of such joint
operations through the use  of ecoregions and subregions (Gallant et al. 1988).
Regional EPA biologists and water quality or standards coordinators can ad-
vise and assist with these interstate cooperative efforts.
    In any case, reference sites or sources for each waterbody type, subcate-
gory of similar waters, and designated use category will be  needed. These
may be drawn from "upstream"  locations, "far field" transects or selected
nearby or "ecoregional" sites representative of relatively unimpacted, highest
quality natural settings (U.S. Environ. Prot. Agency, 1990).
    Care must be  taken to only equate comparable physical characteristics
when selecting reference sites for the waterbodies to be evaluated. A site on a
rapid,  shallow,  rocky piedmont or alpine stream can not be the reference
source against which sites on a slow-moving, larger, brackish coastal stream
are compared.
    The organisms to be collected and communities sampled should represent
an array of sensitivities to  be as responsive and informative as possible. An ex-
ample would be to collect  fish, invertebrates representing both insects and
shellfish, and perhaps macrophytes as elements of the sampling scheme.

    • 3. Collection Methods. The same sampling techniques should always
be employed at both the reference sites and test sites and should be consistent
as much as possible for both spatial and temporal conditions.
    For example, a consistent seining or electroshocking technique should al-
ways be used in collecting  fish  over the same length of stream and with the
same degree of effort using the same gear. In addition, the sampling area must
be representative of the entire reach or waterbody segment. The temporal con-
ditions to be considered include not  only such factors as  the length of time
spent towing a trawl at a constant speed but also extend to the times of year
when data are gathered. Seasonally of life cycles and natural environmental
pressures must be addressed to make legitimate evaluations. For example, the
spring hatch of aquatic insects is usually  avoided as a sampling period in
favor of more stable community conditions later in the summer. Conversely,
low nutrient availability in mid-summer may temporarily but cyclically re-

duce the abundance of estuarine or marine benthos. Dissolved oxygen cycles
are another seasonal condition to consider as are migratory patterns of some
fish and waterfowl. The entire array of temporal and spatial patterns must be
accommodated to avoid inconsistent and misleading data gathering.
    Processing and analysis of the collected specimens is usually based on the
number and identity  of  taxa collected and the number of individuals per
taxon.  This preliminary information is the foundation of most of the subse-
quent  analytical  processes used to evaluate community composition. In the
course of examining and sorting the plants or animals, notations should be
made of any abnormal gross morphological or pathological conditions such as
deformities, rumors or lesions. This information on disease and deformities in
itself can be an important assessment variable.
    Taxonomic sorting can also be the basis for functional groupings of the
data, and preservation of the specimens allows  for the option of additional
analyses after the field season is concluded.
    Table 1 is  not all inclusive in the sense of a thorough biological investiga-
tion, but it does represent an initial approach to the selection of parameters for
biological assessment to support the narrative criteria.

 Table 1.—Indicator communities and reference sources for biological criteria.

 Lakes &
 Estuarine &
Fish & macroinvertebrates,
incl. insects & shellfish
Same, also macrophytes
Same as lake & reservoirs
All of above, plus emergent
and terrestrial vegetation &
perhaps wildlife & avian spp.
Fish & macroinvertebrates,
esp. shellfish, echinoderms,
Ecoregion, upstream and
downstream stations
May need to start with trophic
groups; far- and near-field
transects, ecoregions*
Upstream and downstream stations;
where appropriate, far- and
near-field transects, ecoregions*
Ecoregion;* far- and near-field
Far- and near-field transects;
ecoregion* or physiographic
 * Where appropriate; ecoregions that are heterogeneous may need to be subdivided into
  cohesive subregions or these subregions aggregated where financial resources are limited or
  aquatic systems are large (tidal rivers, estuaries, near-coastal marine waters). Also, major
  basins and watersheds could be considered for "keystone indicators' for fish and shellfish.
    • 4. Quality Control. Much of the analytical potential and strength of
any conclusions reached will depend upon the precision and accuracy of sam-
pling techniques and data handling  procedures. Rigorous attention should
therefore be given to the design and consistency of data gathering techniques
and to the training and evaluation of field and laboratory staff. Similarly, cata-
loging and record keeping procedures must be carefully designed and strictly
adhered to by all parries involved. EPA Regional Office personnel can provide
advice and Agency guidance manuals on this  subject. Similarly, many States
already have  excellent quality assurance procedures that can be used as a
foundation for their biological criteria program.

   ' 5. Analytical Procedure*. The usual approach to biological analyses
is to identify the presence of impairment and establish the probability of being
certain in that judgment.
   For example, if there is a significant increase in the number of deformed or
diseased organisms, and a significant decrease in the taxa and/or individuals
and in sensitive or intolerant taxa — given that the physical habitats and col-
lection techniques are equivalent — then the study site may be presumed to be
degraded. This conclusion will have further support if the trend holds true
over time or if probable sources are identified. The apparent source or sources
of  perturbation should then be investigated and further specific diagnostic
tests conducted to establish cause. Remedial action may then follow through
regulatory or other appropriate management procedures.

Application of  Biological Criteria to  State Surface
Water Use Attainability Procedures

   Another application of the data  collected is in the rank  order of all test
sites relative to the benchmark of reference sources established per designated
use category. A hypothetical State-designated use category system might be as

   •  Class I: Highest quality State waters. No discharges of any kind
      and no  significant landscape alterations are permitted  in the basin
      (includes those designated as unique aesthetic or habitat resources
      and fisheries, especially protected shellfish waters). It is a high pri-
      ority of the State that naturally occurring biological life  shall be pro-
      tected in all respects. (Indicator sensitive resident species might be
      included to help define each class, e.g., trout, some darters, mayflies,
      oysters, etc.)

   •  Class II: High quality waters suitable for body contact.  Only
      highly treated discharges of equal or better quality than the receiv-
      ing waters and land  development  with well established  riparian
      vegetative buffer  zones are allowed^ Naturally occurring biological
      life to be protected and no degradation of the waters allowed. (Indi-
      cator sensitive species might be suckers and darters, stoneflies, soft-
      shelled clams,  etc.)

   •  Class III; Good quality water but affected by runoff from pre-
      vailing developed  land uses. Shore zones are protected, but buffer
      zones not as extensive as Class II. Highly treated, well-diluted efflu-
      ent permitted. Indigenous aquatic life  and community  composition
      is protected  and no  further degradation of the receiving waters is al-
      lowed. (Indicator sensitive species  might be sunfish, caddisflies,
      blue crabs, etc.)

   •  Class IV: Lowest quality water In State's designated use sys-
      tem. Ambient water quality must be or become sufficient to support
      indigenous aquatic life and no further degradation is allowed. Struc-
      ture and function  of aquatic community must be preserved, but spe-
      cies composition may differ from Class HI waters.

    Since all States have some form of designated use classification system
such as that illustrated above, bioassessment procedures can be applied to
each surface water type by class and the information used to help determine
relative management success or failure. In concert with other measurements,
bioassessments help determine designated  use  attainment under the Clean
Water Act, Section 305 (b), which requires periodic reports from the States on
the status of their surface water resources. The procedure also can be used to
support regulatory actions, detect previously unidentified problems, and help
establish priorities for  management projects (see "Additional Applications of
Biological Criteria," Page 8).
    The simplified table that follows (Table 2) illustrates the above approach to
rank ordering comprehensive surface water  quality conditions by each desig-
nated use to help determine and report relative "designated use attainment".

 Table 2.—Data display to facilitate evaluating waterbody condition and
 relative designated use attainment.
 (per Sf. water type)
 Taxa     Taxa Fish  Invertebrates      Fish
Inverte               Intolerant*    Intolerant!
 Highest quality in      high       high
 designated use
 Good quality in
 designated use
 Adequate to
 designated use
 Marginal for
 designated use
 Poor quality           low        low
(per Sf. water type) T. Coll E. Coll
Highest quality in low low
designated use :
Good quality in 1
designated use
Adequate to j
designated use
Marginal for
designated use
D.O. pH PO4 NO3 Turfo.
high | Usually Usually Usually
low low low
region .



 Poor quality
high     high
Usually  Usually  Usually
  high     high     high
    It is important to construct and calibrate each table according to consistent
regional and habitat conditions.
    Using quantitative biological criteria derived from the data base and the
reference condition, standings in the tables can be established from which the
relative rankings can be defined. This material can  eventually serve as the
basis for numeric biological criteria.

        Further, the compiling of physical and chemical data with the biological
    data facilitates comprehensive evaluations  and aids in the investigation  of
    causes of evident water quality declines. Having the numbers all in one place
    helps the water resource manager assess conditions. However, it is important
    to note that States are not to establish any priorities among the different phys-
    ical, chemical, public health, or biological parameters in management or regu-
    lations because different conditions are measured in each instance. Failure of a
    designated site to meet any one of a State's physical, chemical, or biological
    criteria should be perceived as sufficient justification for remedial action.
        One other note on the use of biological criteria is important. The data gath-
    ered should be comprehensively evaluated on a periodic basis. This gives the
    manager an opportunity to assess  relative monitoring and management suc-
    cess, monitor the condition of the reference sites, and adjust procedures ac-

    Additional Applications of Biological Criteria

        As shown in the previous illustrations, narrative biological criteria can
    have many applications to the management and enhancement of surface water

        • Refinement and augmentation of existing waterbody monitor-
          ing procedures. With between 200 and 500 new chemicals entering
          the market annually, it is impossible to develop chemical  criteria
          that address them all.  Further, synergism between even regulated
          chemicals meeting existing standards may create degraded condi-
          tions downstream that are identifiable only by using biological mon-
          itoring  and criteria.  Thus, the approach may help identify and
          correct problems not previously recognized.

        • Non-chemical impairments (e.g., degradation of physical habitats,
          changes in hydrologic conditions, stocking, and harvesting) can be
          identified. Remediation of these impairments, when they are the pri-
          mary factor, can be less expensive and more relevant than some
          point source abatements.

        • Priority determinations  In waterbody management decision-
          making. By presenting an array of diverse parameters in a compre-
          hensive  manner, the  decisionmaker  is   able to  make  better
          judgments. The strengths of this diversity can be used to determine
          with greater confidence the priority to assign to a given waterbody
          in the allocation  of scarce manpower or funds. By using a triage  ra-
          tionale with the comprehensive and diverse database,  the greatest
          use can be gained from  a given budget.

        • Regulatory aspect. Once a satisfactory database is accumulated,
          the biological criteria can  be established to the satisfaction of the
          State and  EPA. The process may then be incorporated in the State's
          system of regulations as part of its surface water quality protection
          and management program. Biological assessment and  criteria can
          become an important additional tool in this context as the Nation in-
          creasingly upgrades the quality of our water resources.

Perspective of the Future: Implementing Biological

    This guide to narrative biological criteria was composed with the fiscal
and technical constraints of  all the States, Territories,  and Reservations in
mind. The array of scientific options available to biological assessment and cri-
teria illustrated here is by no means exhaustive, and many jurisdictions will
prefer a more involved approach. In no way is this guide intended to restrain
States from implementing more detailed or rigorous programs. In fact, we
welcome comments and suggestions for additional techniques and parameters
to consider.
    The basic approach discussed here, while compiled to be the least de-
manding on State budgets, equipment, and manpower pools, consists of a reli-
able, reproducible scientific  method. The metrics considered should not be
restricted to those illustrated  in this guide.  Rather, they should be developed
from the expertise of State biologists and water resource managers — perhaps
in concert with colleagues in neighboring States for a coordinated regional ap-
proach to waterbodies and  natural biological  regions that cross political
boundaries.  Good  science should be applied to a realistic appraisal of what
can actually be accomplished. For more detailed discussions of sampling and
analytical methods, the reader is referred to the  references appended to  this
    A key point to consider is  that the structure for narrative biological criteria
is an ideal interim step for the eventual development of numeric biological cri-
teria. The infrastructure developed  now may only require expansion and re-
finement to meet future needs.
Capper, ]., G. Power and F.R. Shivers, Jr. 1983. Chesapeake Waters, Pollution, Public Health,
    and Public Opinion, 1607-1972. Tidewater Publishers, Centreville, MD.
Gallant, A.L. et al. 1989. Regionalizalion as a Tool for Managing Environmental Resources.
    EPA/600-3-89-060. Environ. Res. Lab., U.S. Environ. Prot. Agency, CorvaJlis, OR.
U.S. Environmental Protection Agency. 1990. Biological Criteria National Program Guidance
    for Surface Waters. EPA/440-5-90-004. Office of Water, U.S. Environ. Prot. Agency,
    Washington DC.
Additional  References

Mem, DJ. et al. 1990. Macromvertebrate Field and Laboratory Methods for Evaluating the
   Biological Integrity of Surface Waters. EPA/600/4-90/030. Environ. Monitor. Syst. Lab.,
   U.S. Environ. Prot. Agency, Cincinnati, OH.
Plafkin, J.L. et al. 1989. Rapid Bioassessment Protocols for Use in Streams and Rivers: Benthic
   Macroinvertebrates and Fish. EPA/444/4-89-001. Office of Water, U.S. Environ. Prot.
   Agency, Washington DC.
U.S. Environmental Protection Agency. 1991. Technical Support Document for Water Qual-
   ity-based Toxics Control. EPA/505/2-90-001. Office of Water, Washington DC.

     U.S.  EPA Regional  Sources  of

     Technical  Assistance

     REGION 1:  JFK Federal Building, Boston, MA 02203
        Regional Biologist: Pete Nolan/Celeste Ban- (617) 860-1343
        Monitoring Coordinator: Diane Switzer (617) 860-4377
        Water Quality Standards Coordinator Eric Hall (617) 565-3533
     REGION 2i  26 Federal Plaza, New York, NY 10278
        Regional Biologist: Steve Ward/Jim Kurtenbach (201) 321-6716
        Monitoring Coordinator: Randy Braum (201) 321-6692
        Water Quality Standards Coordinator: Richard Balla (212) 264-1559

     REGION 3: 841 Chestnut Street, Philadelphia, PA 19107
        Regional Biologist: Ron Preston (304) 233-2315
        Monitoring Coordinator: Chuck Kanetsky (215) 597-8176
        Water Quality Standards Coordinator: Linda Hoist (215) 597-0133

     REGION 4: 345 Courtland Street, NE, Atlanta, GA 30365
        Regional Biologist: Hoke Howard/Jerry Stober/William Peltier (404) 546-2296
        Monitoring Coordinator: Dan Aherm (404) 347-2126
        Water Quality Standards Coordinator. Fritz Wagener/Jim Harrison (404) 347-33%
     REGION Si 230 South Dearborn Street, Chicago, IL 60604
        Regional Biologist: Charles Steiner (312) 886-6233
        Monitoring Coordinator: Wayne Davis (312) 886-6233
        Water Quality Standards Coordinator: David Allen (312) 886-0135

     REGION 6: 1445 Ross Avenue, Suite 1200, Dallas, TX 75202
        Regional Biologist: Evan Homig/Philip Crocker/Terry Hollister (713) 983-2163
        Monitoring Coordinator: Charles Howell (214) 655-2289
        Water Quality Standards Coordinator: Cheryl Overstreet (214) 655-7145
     REGION 7:  726 Minnesota Avenue, Kansas City, KS 66101
        Regional Biologist: Michael Tucker/Gary Welker (913) 236-3884
        Monitoring Coordinator. John Helvig (913) 236-3884
        Water Quality Standards Coordinator. John Houlihan (913) 551-7432

     REGIONS: 999 18th Street, Suite 500, Denver, CO 80202-2405
        Regional Biologist: Loys Parrish (303) 236-5064
        Monitoring Coordinator Jim Leuy (303) 236-7372
        Water Quality Standards Coordinator Bill Wuerthde (303) 293-1586

     REGION 9: 75 Hawthorne Street, San Francisco, CA 94105
        Regional Biologist: Peter Husby/Milton Tunzi (415) 744-1488
        Monitoring Coordinator Ed Liu (415) 744-2006
        Water Quality Standards Coordinator: Phillip Woods (415) 744-1994

     REGION 10:1200 Sixth Avenue, Seattle, WA 98101
        Regional Biologist: Joseph Cummins (206) 553-0370
        Monitoring Coordinator. Gretchen Hayslip (206) 442-1685
        Water Quality Standards Coordinator Sally Marquis (206) 442-2116

     HEADQUARTERS: 401 M Street SW, Biocriteria Program (WH 585),
     Washington, DC 20640
        Program Coordinator: George Gibson (202) 260-7580

     NOTE: Address provided is the EPA Regional Office; personnel indicated may be
     located at satellite facilities.