June 4, 2001 Update on Activities Related to the Chesapeake Bay
Water Quality Steering Committee
Summary of Actions Taken, Issues Resolved, Products Draft
Since the March 27th WQ Steering Committee Meeting

Tidal Waters Designated Uses
Migratory Spawning and Nursery

Got review of/positive feedback from Delaware state fisheries managers and the Chesapeake
Bay Stock Assessment Committee on the use delineation and the proposed February 15th-
June 10th dates for the defining the seasonal application of the migratory spawning and
nursery designated use.

Shallow Water

The Water Clarity Criteria Team has produced a working draft set of water clarity criteria
application depths. See Water Clarity Criteria below for more details.

Open Water/Deep Water/Deep Channel

Chesapeake Bay Program Office staff have prepared a working draft approach to delineating
the boundaries for the open water/deep water/deep channel designated uses. The
development of these delineations were not nearly as straightforward as originally envisioned
(the Bay ecosystem does not tend to adhere to any routine patterns over time!), hence a much
greater amount of time was required to run down a host of different options.

These designated use boundaries are to be considered working drafts subject to change based
on planned stakeholder and scientific reviews as well as we continue to factor in the results of
Bay water quality model scenarios to be run through the summer and into the fall.

Next steps in firming up the tidal water designated uses are:

-	Get the working draft boundary delineation reviewed by the Water Quality Standards
Coordinators Team and the Dissolved Oxygen Criteria Team by mid-June; and

-	Complete work on the more comprehensive documentation on the technical basis for the
five proposed tidal waters designated uses in time for Water Quality Standards
Coordinators Team review and sign-off via a conference call before the end of June.

For more details on all five designated uses, please see the Water Quality Standards
Coordinators Team's web page at www.chesapeakebay.nel/wqsctg.htm

Chesapeake Bay Criteria

Dissolved Oxygen Criteria

The Dissolved Oxygen Criteria team has reached agreement on a draft set of Bay specific
dissolved oxygen criteria (see Table 1), each of which are briefly described below.

Migratory Spawning/Nursery Use

-	To ensure full protection of freshwater warmwater species early life stages, the 7 day
mean of 6 mg/L criterion value from EPA's 1986 Freshwater Dissolved Oxygen Criteria
document was selected.

-	To ensure full protection of not only survival and recruitment of larvae into the juvenile
population, but also to eliminate any potential for adverse impacts on the growth during
critical larvae and early juvenile life stages, the 1 day instantaneous minimum of 5 mg/L


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criterion was selected.

Shallow Waters/Open Waters Use

-	To ensure full protection of survival and recruitment of larvae into the juvenile
population, reduce the potential for adverse impacts on growth, and protect the survival
of a listed endangered species, criteria values of 30 day mean of 5 mg/L, 7 day mean of 4
mg/L, and 1 day instantaneous minimum of 3.5 mg/L were selected.

Deep Waters Use

-	To ensure the protection of survival and recruitment of Bay anchovy eggs and larvae into
the juvenile population, a species critical to the integrity of the Chesapeake Bay
ecosystem, criteria values of 30 day mean of 3 mg/L and 1 day instantaneous minimum of
1.7 mg/L were selected from the combined egg and larvae recruitment effects curves.

Deep Channel Waters Use

-	To ensure the survival of benthic infaunal worms and clams, a criterion value of 1 day
instantaneous minimum of 1 mg/L was selected based on a wealth of effects data.

The team determined that for each of the above criteria which included a 1 day minimum
concentration criterion value, that value would be applied as an instantaneous concentration
based on the effects information used as the basis for the criterion.

Next steps for firming up the dissolved oxygen criteria are:

-	Building from an existing 8 page document which lays out the basis/rationale for the draft
proposed dissolved oxygen criteria, the Dissolved Oxygen Criteria Team will complete
its work drafting up more extensive criteria documentation; and

-	Seek team review of and sign-off on the criteria documentation via a conference call
before the end of June.

For more details, please see the Dissolved Oxygen Criteria Team's web page at
www.chesapeakebay.nel/doctg.htm.

Chlorophyll Criteria

The Chlorophyll Criteria team has developed a working draft range of chlorophyll a criteria
based on the integration of four lines of evidence: ecosystem trophic status, direct
contribution to water clarity, contribution to dissolved oxygen, and higher trophic level food
quality.

Work on the higher trophic level food quality connection with chlorophyll a is still a work in
progress, with further quantification of the relationship of varying concentrations of
chlorophyll a with quality of the algae community as fish and shellfish food still underway.
Connections are emerging, but more follow-up analysis is required to pull out and clearly
illustrate the relationships between chlorophyll a concentrations, phytoplankton community
integrity, and implications for higher trophic level food quality.

The Chlorophyll Criteria Team is still working towards a set of chlorophyll a criteria-stated
as single concentration spring and summer median concentrations-based on food quality for
higher trophic levels. The current working draft set of criteria are purposely stated as a range
based on all four lines of evidence to reflect the "in progress" nature of the work on the food
quality connection.

The team decided not to recommend the use of a maximum chlorophyll a concentration as
part of the criteria given the natural variability in chlorophyll a concentrations and the lack of

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a scientific basis on which to select a single maximum concentration value.

The team recognizes the relatively low concentrations reflected in the working draft
chlorophyll a criteria concentrations range. The need to and approach taken for accounting
for natural variability and other factors in the application of these criteria were considered to
be policy, not science related issues. These policy issues should be addressed through criteria
application decisions (e.g., details of spatial and temporal averaging to determine criteria
attainment) and possible tidal river/creek/embayment specific changes to designated uses
reflecting habitats where only chlorophyll a concentrations higher than the criteria can ever
be achieved for a variety of documented reasons (e.g., poor flushing leading to long retention
times).

Next steps for firming up the chlorophyll a criteria are:

-	Chlorophyll Criteria Team receipt and review of more complete documentation of
chlorophyll concentrations reflective of better food quality for higher trophic levels to be
distributed by June 11th;

-	Conference call of team members to discuss the documented findings and agreement on
what changes, if any, to make the current working draft range of chlorophyll a criteria;
and

-	Completion of draft documentation for the working draft chlorophyll a criteria by the end
of June.

The working draft criteria concentrations should be applied as a range of target water quality

conditions during the early stages of the cap load setting/allocation process as work proceeds

in parallel to further quantify the chlorophyll a concentration, phytoplankton community

integrity, and higher trophic level food quality interconnections.

For more details, please see the Chlorophyll/Nutrient Criteria Team's web page at

www.chesapeakebay.nel/cnctg.htm

Water Clarity Criteria

The Water Clarity Criteria team had previously agreed to a draft set of water clarity criteria
based on the work published through the second Chesapeake Bay SAV Technical Synthesis
document.

The team has developed a draft set of water clarity criteria application depths tailored to each
Chesapeake Bay Program segment based on the following:

-	Establishment of an existing use depth based on the deeper depth from either the deepest
depth of 1971-1999 composite SAV beds or the deepest depth achieving the draft Bay
criteria calculated using 1985-1999 Bay water quality monitoring data; and

-	Setting a working draft depth of application based on the deepest depth achieving the
draft Bay water clarity criteria calculated from ten year average output from the 33%
percent beyond tributary strategy scenario.

The next steps are to

-	Complete more comprehensive documentation for the water clarity criteria by the end of
June; and

-	Factor additional Bay water quality model scenario output information on maximum
depths achieving the draft Bay criteria for those scenarios achieving the other Bay criteria.

Steps have been taken to coordinate the continued refinement of the working draft water

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clarity application depths with efforts under the direction of the CBP Living Resource
Subcommittee and its SAV Workgroup to develop revised SAV restoration goals for the Bay
based on historical SAV distributions dating back to the 1930s and 1950s (a 2002
commitment in the Chesapeake 2000 Agreement).

For more details, please see the Water Clarity Criteria Team's web page at
www.chesapeakebav.nel/wcctg.htm.

Baywide UAA

Since the March meeting, CBPO staff have been talking with EPA Headquarters senior
managers and staff about securing HQ support (both EPA technical staff and contractual) for
the Baywide UAA.

A team of EPA headquarters water quality standards specialists, UAA experts, and
economists has been assembled to work directly with the Chesapeake Bay watershed partners
through the next round of details for undertaking an economic analysis as part of the Baywide
UAA.

Allison Wiedeman from the Chesapeake Bay Program Office has been assigned the staff lead
responsibility on behalf the Bay watershed partners to coordinate and lead the Baywide UAA
process.

The Water Quality Standards Coordinators Team will continue to have lead responsibility for
coordinating between all the partners and ensuring all the Bay watershed partners are directly
involved in the Baywide UAA.

For more details, please see the Water Quality Standards Coordinators Team's web page at
www.chesapeakebay.nel/wqsctg.htm.

Basinwide Permitting Approach

Further follow-up meetings with EPA Headquarters senior managers has effectively firmed
up their support for the proposed basinwide approach to addressing numerical permit limits
for point sources.

More complete documentation on the proposed basinwide permitting approach has been
drafted.

Chesapeake Bay Foundation's Chesapeake 2000 Funding Needs Estimates

At the March meeting, an invitation went out to Delaware, West Virginia, and New York
partners to join in a group set up to work closely with the Chesapeake Bay Foundation on its
efforts to cost out the funding needed to fully implement the Chesapeake 2000 Agreement.
Since then, the Chesapeake Bay Commission has committed the time of its executive director
to work with directly CBF. The other signatoryjurisdictions have also since appointed
specific staff leads.

Meetings with Jurisdictions

Meetings with jurisdictional representatives and key stakeholders have been held to date with
Maryland, Pennsylvania, Virginia, and New York. Meetings with Delaware, District of
Columbia, and West Virginia are being scheduled.

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