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DRAFT "REMOVING IMPEDIMENTS TO MIGRATORY
 FISHES IN THE CHESAPEAKE BAY  WATERSHED"

          An Agreement Commitment Report from the
                  Fish Passage Workgroup
                                               U.S. Environmental Pr«tection Agency
                                               Region III Infgrmaiiin Resource
                                               CsiJler (3PM52)
                                               841 Chestnut Street
                                               Philadelphia, PA 19107
                   Annapolis, Maryland

                     September 1988

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                       TABLE OF CONTENTS

EXECUTIVE SUMMARY	PAGE i

INTRODUCTION 	PAGE 1

BARRIERS TO MIGRATION: AN
HISTORICAL PERSPECTIVE	PAGE 2

A MULTI-FACETED APPROACH IS
RECOMMENDED TO ASSURE THE REMOVAL
OF IMPEDIMENTS TO FISH MIGRATION	PAGE 5

TECHNICAL RESOURCES DEDICATED TO THE
REMOVAL OF IMPEDIMENTS TO FISH
MIGRATION IN THE BAY WATERSHED
SHOULD BE SUPPLEMENTED	PAGE 9

A COMPREHENSIVE INVENTORY OF
OBSTRUCTIONS TO FISH MIGRATION
IN THE BAY WATERSHED SHOULD
BE COMPILED	PAGE 11


                 TABLES AND FIGURES

TABLE 1: RECENT COMMERCIAL HARVESTS OF
MIGRATORY SPECIES	PAGE 2

FIGURE 1: ESTIMATED HISTORIC RANGE OF
MIGRATORY FISH OBSTRUCTED BY STREAM
BLOCKAGES: CHESAPEAKE BAY WATERSHED	PAGE 4

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                       EXECUTIVE SUMMARY


     The 1987 Chesapeake Bay Agreement includes a commitment
that the signatories will "provide for fish passage at dams, and
remove stream blockages wherever necessary to restore passage for
migratory fish." This commitment was made in response to
precipitous declines.in the Bay's migratory fisheries and because
of the recognition that these declines may be attributable, in
part, to the loss of historic spawning and nursery habitat as a
consequence of dams and other impediments. In January of 1988 the
Living Resources Subcommittee appointed a work group to develop a
strategy for implementing the Bay Agreement's commitments
regarding fish passage. This work group included representatives
from each of the Bay states, the District of Columbia,
appropriate federal resource agencies, and the environmental
community. This report contains the work group's findings and
recommendations.

     During the past two centuries, a major portion of the
historic migratory fish spawning and nursery habitat has been
lost as a consequence of dams and other obstructions. The removal
of these obstructions is an essential element in our efforts to
reestablish healthy migratory fisheries in the Bay watershed.
Because the structures that act as impediments to fish migration
are diverse, ranging from small road culverts to major
hydroelectric facilities, it is important that all responsible
parties work together to assure the provision of fish passage.
Remedying this problem will require a new level of commitment
from our state highway departments, from local government, from
our state and federal resource agencies, and from utilities
operating hydroelectric dams in the watershed.

     In addition to the construction of fish passages at dams and
other blockages, the work group recommends that jurisdictions in
the watershed initiate programs aimed at reintroducing migratory
species in rivers and streams targeted for restoration.
Furthermore, measures should be taken that will assure the
protection of newly introduced fish and the maintenance of water
quality levels that will support their successful
reestablishment. It is also important that programs be
established to monitor the success of fish passage initiatives
and to assure that the public is made aware of the importance of
this issue to Bay fisheries.

     There was a consensus among work group members that
technical expertise in the Bay watershed needs to be supplemented
if we are to implement an effective fish restoration program.

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This shortcoming should be remedied by the addition of personnel
in our state resource agencies capable of designing and
supervising the construction of fish passage projects, state
efforts should be supplemented by additional technical assistance
from the Fish and Wildlife Service. Long term technical needs
should be addressed, in part, by taking steps that will encourage
educational institutions in the watershed to focus resources on
this important problem. It is also recommended that an ongoing
workgroup be appointed by the Living Resources Subcommittee to
coordinate future activities relating to the provision of fish
passage.

     Finally, the workgroup recommends the compilation of a
comprehensive inventory of obstructions to fish passage in the
Bay watershed. Accurate information on the nature and location of
impediments to fish passage is essential to the success of any
fishway program. A substantial body of information on
obstructions to migration is currently available. Major
impediments to fish passage in the watershed have already been
identified. These impediments should be the initial focus of our
remedial efforts. The report summarizes the currently available
information on stream blockages and notes gaps in the data where
they exist.
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                           INTRODUCTION

     Of the approximately 260 fish species that occur in the
Chesapeake Bay, perhaps the most revered, and most sought after
by both sport and commercial fishermen, are the migratory
species.  These include "anadromous" fish, such as striped bass,
river herring, sturgeon and shad, that spend most of their adult
lives in saltier coastal waters but return each year to spawn in
freshwater, as well as semi-anadromous species such as white and
yellow perch.  The term anadromous is taken from the Greek words
"ana", meaning upward, and "dromos", meaning a running.  Another
class of migratory fish are the "catadromous" species,
represented in the Bay watershed by the American eel.
Catadromous fish spend most of their lives in freshwater,
returning to ocean waters to spawn. Together, anadromous and
catadromous species are described as diadromous.
     At one time, the Chesapeake Bay abounded with migratory
fish.  Today, however, these once thriving fisheries are in a
•depressed state.  No longer do sturgeon, striped bass, shad and
river herring support extensive recreational and commercial
fisheries.  In Maryland, the catch of American shad declined
from over 7 million pounds a century ago to approximately 20,000
pounds in 1980, prompting the state to ban fishing for this
species.  Populations of shad in Virginia waters have experienced
a similar decline, with current annual harvests averaging
900,000 pounds, compared to over 11 million pounds a hundred

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years ago.  The total annual commercial landings of river herring
in Maryland has dropped from over 8 million pounds 50 years ago    ™
to approximately 200,000 pounds in 1985.  The striped bass
commercial catch Bay-wide has declined from 14.7 million pounds
in the early 1970's to 1.7 million pounds in the early 1980's.
Table 1 illustrates the precipitous decline of the Bay's
migratory fisheries.
     The economic impact of this decline is significant. In the
early twentieth century the shad and river herring fisheries were
the two most economically important commercial fisheries in the
Bay watershed. Today Maryland's commercial shad fishery is
closed as a result of a moratorium imposed in 1980 and the
herring fishery is a shadow of its former self. The economic
importance of the Bay's migratory species to the sportfishing
industry is equally apparent.   .                                    ™
     This decline cannot be attributed to a single cause.
Rather, an intricate complex of factors — some natural, most
man-made — can be identified.  Among those most often cited are
pollution and siltation of spawning areas, overharvesting, and
construction of dams and other obstructions across the Bay's
tributary streams and rivers, preventing access to historic
spawning areas.  Through the multi-agency Bay restoration
program, significant progress has been made in addressing the
degradation of Bay water quality.  The 1987 Bay Agreement has
bolstered these efforts by establishing specific commitments to
reduce nutrient input and sedimentation into Bay waters.  Harvest

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TABLE 1
RECENT COMMERCIAL HARVESTS
OF MIGRATORY SPECIES
(average annual tons for each 10-year period)
American Eel
American Shad
Hickory Shad
River Herring
Striped Bass
White Perch
Yellow Perch
TOTAL
* — pre-moratorium
VA
MD
VA
MD
VA
MD
VA
MD
VA
MD
VA
MD
VA
MD.
VA
MD

1966-75
427.1
117.8
1,114.0
409.7
18.8
8.7
9,486.0
1,094.7
1,059.0
1,803.3
173.8
650.8
1.9
51.8
12,280.6
4,135.9
16,417.4

1976-85
257.0
106.7
454.0
37.4*
0.5
0.6
725. 0'
71.0
226.0
642.4*
65.0
341.9
0.2
14.9
1,727.7
1.214.9
2,942.6

% Decline
40%
9%
59%
91%
97%
93%
92%
94%
79%
64%
63%
47%
90%
71%
86%
Hi
82%


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restrictions have been placed on the taking of some migratory
species in an attempt to arrest further decline.  Until recently,
however, little had been done to address the blockage of historic
diadromous fish spawning habitat by dams, culverts and other
physical obstructions.

     BARRIERS TO MIGRATION: AN HISTORICAL PERSPECTIVE
     Altering and impounding streams and rivers to meet the needs
of a growing populace is a practice as old as the Nation itself.
Beginning in colonial times, mill dams multiplied to meet the
growing needs of commerce.  As early as 1774, a navigation canal
was proposed for the James River.  Many of our founding fathers
were actively involved in improving navigation on the James and
other Virginia Rivers, facilitating bettex transportation but
creating impediments to migrating fish and restricting once
productive spawning areas.
     As domestic and foreign commerce began to flourish
throughout the fledgling Nation, canal systems were developed on
most major East Coast rivers to facilitate the transport of goods
and people.  An integral part of these early systems was the
construction of locks created by dams.  While these structures
improved navigation for boats and barges, for the first time
spawning and nursery rivers used over the centuries by migratory
fish began to be obstructed.
     With the advent of the Industrial Revolution, the potential
energy of the rivers was harnessed as dams were built to provide

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POTENTIAL  AMERICAN  SHAD SPAWNING  AND
 NURSERY HABITAT OF MAINSTEM  RIVERS *
                                                                            Susquehanna
                                                                          habitat continues
                                                                           into New York
                                                                                First blockage on
                                                                                mainstem river

                                                                                Potential habitat
                                                                                currently blocked
* Potential habitat in the smaller tributaries of
 the mainstem rivers too detailed 10 include
                                                                                 Norfolk

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a source of impounded water to drive the mills. Mill dams gave
way to huge concrete structures built to provide a source of
electricity for growing metropolitan areas.  Overland
transportation expanded as the horse and buggy gave way to the
automobile and dirt trails were paved and expanded into roads and
highways.  Culverts and other structures placed in or across
streams and rivers to support these roads were added to the
growing inventory of blockages. Thus, the foundation was laid
for a conflict between commercial interests and the environment
that would plague natural resource managers into the 20th
century.
     During the past two centuries, a major portion of migratory
fish spawning and nursery habitat throughout the Bay has been
lost due to downstream obstructions.  The Susguehanna River is
perhaps the most dramatic example of the impacts of blockages on
migratory fish.  Construction of the Conowingo Dam on the East
Coast's largest river in 1928 blocked nearly 300 miles of habitat
historically used by American shad and other herrings.  The
river's annual shad harvest, which reached 7.1 million pounds in
1890, plunged to a meager 34,000 pounds in 1979, causing resource
managers to impose a full moratorium on the catch of this fish.
     Further south, a similar fate has befallen the migratory
fishery resources of the James River.  At one time anadromous
fish migrated nearly 300 miles upstream, to the river's origin at
the confluence of the Jackson and Cowpasture Rivers.   Today,
however, 5 concrete dams located in the vicinity of Richmond

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block fish access to nearly two-thirds of historic habitat.
While the Susquehanna and James Rivers may be two of the more
dramatic illustrations of the problem, blockages plague virtually
every major tributary of the Bay.  Figure 1 depicts historical
spawning and nursery areas currently precluded by impediments to
fish migration.  Nearly a thousand such blockages are documented
in both Virginia and Maryland.  In response, in recent years
resource managers have begun to assess this problem more closely
to identify remedial measures.  These concerns culminated in 1987
when the authors of the new Chesapeake Bay Agreement included a
specific commitment "to provide for fish passage at dams, and
remove stream blockages wherever necessary to restore passage for
migratory fish."
        In January, 1988 the Living Resources Subcommittee
appointed a work group to develop a strategy for implementing the
Bay Agreement's commitment to restore passage for migratory fish.
The work group is composed of representatives from each of the
Bay states, the District of Columbia, appropriate federal
resource agencies, and the environmental community. At its first
meeting in February the work group identified several issues that
would be the focus of future deliberations. These key issues are
summarized below:
     A MULTI-FACETED APPROACH IS RECOMMENDED TO ASSURE THE
     REMOVAL OF IMPEDIMENTS TO FISH MIGRATION
     The structures that act as impediments to fish migration are
diverse, ranging from major hydroelectric facilities to road

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culverts. No one solution or instrumentality can effectively
assure the provision of fish passage.  Instead,  it is essential
that all responsible parties work together to remove stream
blockages that impede the spawning runs of migratory species.
The work group thus recommends a multi-faceted approach to this
problem. Beginning with the smallest impediments to fish passage,
we make the following recommendations:
     - All future road and highway culverts should be designed
and constructed to assure the passage of migratory fish species
present or potentially present in the affected stream. Within
each Bay state, the highway department should prepare, with the
assistance of other responsible agencies, an inventory of
existing culverts that act as impediments to migratory fish, and
prepare .a strategy for remedying this problem.
     - Many of the dams that impede fish passage are small
structures. Designing fishways for these structures is often a
relatively straightforward process. We recommend that each Bay
state compile an inventory of impediments to fish passage and
establish a .priority list for future fishway projects at these
smaller obstructions. As mentioned below, it is essential that
each state possess the technical expertise necessary to make
provision for fish passage at these obstructions.
      We believe that our ability to provide fishpassage at small
dams would be greatly improved by the active participation of
local governments. The current fishway program in Massachusetts
demonstrates the value of such cooperative efforts. The

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Massachusetts Division of Marine Fisheries designs and assists in
the construction of small fish passages. Local townships
contribute through the provision of heavy equipment and the
purchase of concrete and other building materials. As a
consequence of these cooperative efforts, the cost of
constructing fish passage facilities is in many cases
significantly reduced. The excellent record of the Massachusetts
program has generated an extraordinary level of public support.
     The Massachusetts program is one possible model for the Bay
states to consider. Whatever option they choose, the Bay states
should take steps to assure that adequate resources are provided
to permit meaningful progress in creating fish passages at these
small dams. We recommend that the states creatively explore ways
to assure the provision of adequate funding for these projects.
We further recommend that all jurisdictions in the watershed take
steps to assure that they possess adequate legal authority to
carry out an effective fish passage program. A brief summary of
the current law in the Bay watershed as it relates to fish
passage is attached to this report as Appendix 4. Finally, it is
essential that steps be taken to assure that adequate resources
exist to operate and maintain fishways once they are constructed.
     -Although the number of major hydroelectric facilities in
the Bay region is not large, these large dams currently prevent
migratory fish from utilizing hundreds of miles of potential
spawning and nursery habitat. Efforts to provide fish passages at
these facilities have accelerated in recent years, partly as a

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consequence of voluntary agreements between state and federal
resource agencies and utilities, but much work remains to be
done. It should be recognized that efforts at smaller, upstream
blockages will not be completely successful absent a similar
commitment at the hydroelectric facilities and other blockages
that obstruct the downstream areas of many of the Bay's
tributaries. It is the workgroup's recommendation that the
licensing process for all facilities regulated by the Federal
Energy Regulatory Commission be reopened, where necessary, to
assure that adequate provisions are made for fish passage within
a reasonable time frame. In no case should any new licenses for
hydro-electric projects be issued in the watershed absent the
assurance that adequate steps will be taken to assure the passage
of migratory fish.
     - The workgroup recommends that state and federal resource
agencies initiate reintroduction programs for migratory fish,
when necessary and appropriate, above impediments that have been
targeted for fish passage projects. The upstream introduction of
migratory species prior to the construction of fish passage
facilities "imprints" young fish and increases their disposition
to return, in future years, to the targeted stream. This practice
can expedite the recovery of migratory species in waters where
they are currently few in number. One way to do this is to trap
adult fish below the targeted blockage and transport them
upstream to spawn. A second method is to stock young hatchery
produced fish above the impediment. To implement this

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recommendation the Bay states should identify potential sources
of migratory fish for transport efforts, and acquire any
equipment necessary for the transport of these fish. It is also
suggested that the states implement management plans, regulatory
measures and monitoring programs that will protect newly
introduced fish until a self sustaining population has been
established. In addition, measures should be taken to assure that
water quality in targeted streams is maintained at levels
necessary for the reestablishment of migratory species.
     - Public education is essential to the long term success of
this initiative, just as it is the cornerstone of all our efforts
to restore the Chesapeake Bay. All possible avenues for public
involvement in and sponsorship of activities related to the
provision of fish passage should be actively explored.
     - Finally, it is important that, from the beginning, the
fishery management agencies monitor the results of their efforts.
Such monitoring is essential in gauging the impact of fish
passage projects on populations of migratory species, and in
assuring the cost effectiveness of future efforts. As recommended
below, the creation of an ongoing Baywide fish passage workgroup
will provide an institutional framework for the assessment of
current and future fish passage initiatives.

    TECHNICAL RESOURCES DEDICATED TO THE REMOVAL OF
   IMPEDIMENTS TO FISH MIGRATION IN THE BAY WATERSHED
   SHOULD BE SUPPLEMENTED

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     There was a consensus among work group members that
technical expertise in the Bay watershed needs to be supplemented
if we are to implement an effective fish passage restoration
program. In particular, there is a strong need to establish
expertise in the area of fishway engineering and design.
     In general, the work group felt that these resource needs
could best be met through a cooperative effort by the responsible
state and federal agencies. Specifically, the work group
concluded that a need exists at the state level for personnel
familiar with the principles of fishway design and capable of
designing and supervising the construction of fish passage
projects. The capabilities of state fish passage programs could
be greatly enhanced in the Bay region by the establishment, in
the U.S. Fish and Wildlife Service, of a technical advisory
office that would act as a resource to state and local government
agencies within the watershed. This office would act as
clearinghouse for information relating to fishway construction
and would act as consultant to the Bay states on selected fishway
projects.As a modest first step, we recommend that the Fish and
Wildlife Service consider enhancing their anadromous coordinator
initiative to provide additional assistance in the Bay region. A
similar state\federal cooperative effort currently exists in New
England between the Fish and Wildlife Service and the
Massachusetts Division of Marine Fisheries.
     The work group also suggests that an ongoing Baywide
workgroup of the Living Resources Subcommittee be appointed to

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coordinate future activities relating to the provision of fish
passage. The committee would serve as a forum for the evaluation
of past remedial efforts and the development of future fish
passage initiatives.  The committee should include
representatives from federal agencies whose activities might
contribute to the removal of impediments to fish migration and a
representative from the Chesapeake Bay Commission. We believe
that the committee would also benefit from the insight that
representatives of local governments in the watershed could
provide. The committee would assure that the responsible
authorities work cooperatively in the removal of blockages to
fish passage. In addition it would serve as a forum for the
exchange of information and for the dissemination of that
information to interested members of the public. The committee
would prepare an annual report documenting progress in the
provision of fish passage.
     The workgroup also suggests that the following additional
steps be taken to address existing gaps in technical knowledge.
First, we propose that a technical workshop be held in the Bay
area to apprise interested parties of recent developments
relating to fishway design and construction. This workshop could
be sponsored jointly with the Fish and Wildlife Service through
their short course program on fish passage. We also suggest that
steps be taken that will encourage regional educational
institutions to focus resources on this important problem. The
Fish and Wildlife Service should consider encouraging

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"cooperative units" in the watershed to focus on migratory fish
issues and the engineering and design of fishways.

         A COMPREHENSIVE INVENTORY OF OBSTRUCTIONS  TO FISH
         MIGRATION IN THE BAY WATERSHED SHOULD BE COMPILED
     Accurate information on the nature and location of
impediments to fish passage is essential to the success of any
fishway program. The workgroup recommends that as a long term
goal the responsible agencies work together to compile an up-to
-date, comprehensive inventory of dams and other obstructions to
fish migration in the Bay states. One function of the previously
recommended Baywide work group should be the coordination of this
effort. The inventory should include information on the current
ownership and use of each impediment, the species and numbers of
migratory fish present below the obstruction, and the quality
and quantity of upstream habitat. The inventory should also
identify the location of each blockage by river section and
stream order and provide a physical description of the
obstruction. Where relevant, information concerning the status of
any license issued by the Federal Energy Regulatory Committee
should be provided. Ideally, this information should be compiled
in a central computer data base accessible to all interested
agencies.
    Although data gaps exist, the workgroup believes that
existing information supports the need to take immediate steps to
remove known impediments to fish passage. The location of major

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impediments to fish passage in the Bay watershed have already
been inventoried. Those impediments should be the initial focus
of our remedial efforts. We recommend that the states
periodically reassess their priorities as additional information
becomes available. In the paragraphs that follow currently
available sources of information on impediments to fish migration
in the watershed are summarized.
     In Virginia several surveys have been conducted which
collectively provide an inventory of the larger impediments to
fish passage in the tidewater area. Information on smaller
impediments is currently lacking..  The "Virginia Hydro Dam
Inventory" was prepared in 1981 to provide information about the
hydroelectric potential at existing dams. The inventory includes
descriptions of the physical condition of the state's larger
dams as well as information on ownership.  Two regional surveys
by the Virginia Polytechnic Institute and State University
document stream blockages and water quality on the mainstems of
the Rappahannock, James and York Rivers and tributaries of the
lower James. "An Analysis of the Impediments to Spawning
              i   v
Migrations of Anadromous Fish in Virginia Rivers" was prepared in
1985 and describes physical impediments to migration on the main
stems of the James, York and Rappahannock Rivers. "Use of
Tributaries of the Lower James River by Anadromous Fishes"
identifies the first downstream impediment encountered on 96
tributaries to the Lower James. The studies include a
description of the historic and present ranges of anadromous

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migrations. Detailed information about the use and ownership of
the obstructions and the quality of upstream habitat is not
included.  In addition, field biologists with the Department of
Game and Inland Fisheries have compiled a "Statewide Inventory of
Dams". This inventory is the most inclusive list of dams that
impede fish passage, but does not contain information on non-dam
impediments. In summary, while much information has already been
compiled on stream blockages in Virginia, it needs to be
consolidated and gaps in the data must be filled. Virginia
representatives on the work group suggested that additional
resources may be necessary to collect and organize needed
information. A more detailed description of the aforementioned
surveys, along with a summary of current fishway projects in
Virginia, is attached as Appendix 1.
     In Maryland a more centralized but similar body of
information on impediments to fish passage exists. Between 1968
and 1980 the Maryland Department of Natural Resources compiled a
"Survey of Anadromous Fish Spawning Areas".  The survey
identifies all natural and manmade stream blockages impeding the
passage of migratory fish in 15 of 17 tidewater counties.
Another, similar survey provides a description of impediments in
the two remaining counties.  Although the surveys are fairly
comprehensive, some of the information is dated, and there are
gaps in the available data. Specifically, the current ownership
and use of impediments needs to be documented, and information on
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the presence and abundance of migratory species below blockages
needs to be updated.
     Detailed physical information about larger dams in the state
is compiled in the "Inventory of Maryland Dams and Assessment of
Hydropower Resources", also published by the Department of
Natural Resources. The inventory does not describe habitat
conditions or whether migratory species are present below the
listed dams. A more comprehensive discussion of the status of
fishpassage efforts underway in Maryland is attached as Appendix
2.
     Information on stream blockages in Pennsylvania is also
incomplete at this time. However, migratory fish access to the
main stem of the Susguehanna River will be possible once passage
has been achieved around the four hydroelectric dams in the lower
river.  Emphasis has been placed on negotiations with the
utilities that operate these hydroelectric facilities, and on
upstream stocking.  A survey of habitat quality in the river has
been completed. Many impediments in the river are identified in
the Water Resources Bulletin for Dams, Reservoirs, and Natural
Lakes, published by the state in 1970. The historical importance
of the Susquehanna's anadromous fisheries is documented in a
review authored by Richard St.  Pierre of the U.S. Fish and
Wildlife Service. A copy of the review is attached as Appendix 3.
     Information on blockages to fish passage within the District
of Columbia is primarily restricted to the Rock Creek system and
summarized in several publications and studies.  The Rock Creek

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Watershed Conservation Study compiled by the National Park
Service provides a detailed account of water quality, hydrology,
land usage, spawning conditions and barriers to fish migration.
A subsequent study conducted in 1983 (Liz Houghton) specifically
evaluates stream barriers and proposes recommendations for
mitigation.  The D. C. Fisheries Program is currently
collaborating with the National Park Service to monitor resident
and migratory fish populations in this system in order to make
additional recommendations and prioritize restoration efforts.
     The fish populations of the Anacostia River drainage are
described with reference to earlier studies in a report entitled
Resource Identification Study for the Anacostia River (Dietemann
and Giraldi 1973).  While the report does not specifically
describe the effect of barriers to fish migration, the
distribution of fish populations are compared to historical
ranges, providing insight into the extent of habitat degradation
and current usage.  The D. C. Fisheries program is supporting a
present ICPRB study designed to update this work.  It is
expected that detailed information on the Anacostia system,
particularly with respect to blockages and their effect on
anadromous fisheries resources, will be available within a year.
     Other blockages, located outside the jurisdiction of the
District of Columbia, directly impinge on local anadromous
fishery resources and are of concern to District fisheries
managers; notably, the municipal water supply dam at Little
Falls situated on the Potomac River and several smaller blockages

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in the Anacostia drainage streams that terminate in the District
require fish passage.  The District has substantial interest in
identifying and mitigating these blockages and is prepared to
lend support to future fish passage restoration.
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