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the Technical Support Document-2004 Addendum , was to count all of the SAV 
acreage for a given segment that occurred within the single best year regardless of 
any shoreline, bathymetry data limitations or water clarity application depth restric¬ 
tions. 
The Technical Support Document-2004 Addendum documents the ‘expanded 
restoration acreage’, updated existing use acreage and the available shallow-water 
habitat area for each Chesapeake Bay Program segment (U.S. EPA 2004). As 
described in the addendum: 
The ‘expanded restoration acreage’ is the greatest acreage from among the 
updated existing use acreage (1978-2002; no shoreline clipping), the Chesa¬ 
peake Bay Program adopted SAV restoration goal acreage (strictly adhering 
to adopted single best year methodology with clipping) and the goal acreage 
displayed without shoreline or application depth clipping and including SAV 
from areas still lacking bathymetry data. This ‘expanded restoration 
acreage’ is being documented here and provided to the partners as the best 
acreage values that can be directly compared with SAV acreages reported 
through the baywide SAV aerial survey. These acreages are not the officially 
adopted goals of the watershed partners; they are for consideration by the 
jurisdictions when adopting refined and new water quality standards 
regulations. 
The Chesapeake Bay Program SAV restoration goal of 185,000 acres and the 
segment-specific goal acreages stand as the watershed partners’ cooperative restora¬ 
tion goal for this critical living resource community (Chesapeake Executive Council 
2003). EPA recommends that the jurisdictions with Chesapeake Bay tidal waters 
consider adopting the expanded restoration acreages (which factor in the updated 
existing use acreages) and shallow-water habitat acreages determined using the 1:2.5 
ratio into their refined and new water quality standards regulations. 
DETERMINING ATTAINMENT OF THE 
SHALLOW-WATER BAY GRASS USE 
In addition to the methods previously described in the Technical Support Document 
(U.S. EPA 2003b) for determining attainment of the shallow-water bay grass desig¬ 
nated use, there is an additional methodology which integrates both progress towards 
to the SAV restoration goal acreage and measurement of suitable shallow water 
habitat acreage necessary to support restoration of the remaining SAV beds needed 
to reach the goal acreage. This methodology calls for assessing attainment of the 
shallow-water designated use in a segment through a combination of mapped SAV 
acreage and meeting the applicable water clarity criteria in an additional, unvege¬ 
tated shallow water surface area equal to 2.5 times the remaining SAV acreage 
necessary to meet the segment’s restoration goal (SAV restoration goal acreage 
minus the mapped SAV acreage). In other words, a segment’s shallow-water bay 
grass designated use would be considered in attainment if there are sufficient acres 
chapter vii 
Updated Guidance for Application of Water Clarity Criteria and SAV Restoration Goal Acreages 
