Revising VAs

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Revising VAs Water Quality StandardsTechnical
basis for tidal James River chlorophyll a
criteria CB Chlorophyll Criteria SERC
May 19, 2005
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Summary
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Current Approach For NutrientsVA Water Quality
Standards

• General Designated Uses Apply Statewide
  Propagation and growth of a balanced, indigenous
  population of aquatic life which might reasonably
  be expected to inhabit them
• Narrative/numeric criteria
• General Narrative Criteria
• All state waters free from.substances which
  nourish undesirable aquatic plant life

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Why Numerical for the James River?Impairments
Due to Nutrients
Rappahannock and York General Criteria Use
Impairment Due to Nutrients (too much) and
Dissolved Oxygen (too little)
James General Criteria Use Impairment Due to
Nutrients (too much)
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Ecological Indications for Assessment of Aquatic
Life in James River

• Community Structure
• Aquatic Plant Life
• Status and Trends
• Imbalances (? chl, spp, abund, biomass, prod,
  div, )
• Undesirable/Nuisance species bloomers HABs
• Zooplankton (micro- meso-) - status trends
• Indices
• Index of Biotic Integrity (Phyto-, Zoo-, Benthic)
• Food Availability Index
• Trophic linkages fish communities

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Indications of Unbalanced Aquatic Life in the
James River Low Biotic Integrity

• Table 2. Phytoplankton IBI for VA's summer tidal
  fresh tributaries (1986-2002, stations TF5.5,
  TF4.2, TF3.3)
• Basin IBI Index
• Rappahannock 2.25
• York 3.39
• James 1.35

Scale of 1-3-5, with 1 representing most degraded
condition and 5 the least-degraded condition
Source Lacouture et al., In prep.
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Indications of High Levels of Undesirable
Species Cyanobacteria Compared Baywide
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Indications of Increasing Levels of Undesirable
Species Cyanobacteria Taxa
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Indications of High Levels of Undesirable
Species Dinoflagellates
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Indications of trophic interactions
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James River Numerical Chlorophyll a Criteria for
James River
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Comments Received

• criterion scientifically invalid
• highly variable
• lack of thresholds
• no quantifiable impairment toxics vs nutrients
• food limitations
• modeling
• food quantity
• balanced ?
• benefits ?
• poor linkages
• designated use
• nutrients to nuisance/undesirable algae
• higher trophic levels (zooplankton to fishes)
• sediments

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All Dissolved Oxygen Criteria
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Migratory Spawning Nursery
6.0 mg/l 7-day mean 5.0 mg/l instantaneous minimum
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5.5 mg/l 30-day mean (0-0.5 ppt) 5.0 mg/l 30-day
man (0.5 ppt) 4.0 mg/l 7-day mean 4.3 mg/l min
at 29 C 3.2 mg/l min at Open Water (and Shallow Water)
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3.0 mg/l 30-day mean 2.3 mg/l 1-day mean 1.7 mg/l
instantaneous minimum
Deep Water
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1
Deep Channel
1.0 mg/l instantaneous minimum
0
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Percent James River Blooms Above Reference
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Increasing Levels of Undesirable
Species Cyanobacteria Trend Upper James (TF5.5)
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Chlorophyll a Concentrations in VA Tidal
Tributaries
James
Rappahannock
York
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Phytoplankton Index of Biotic Integrity (P-IBI)
...balanced, indigenous population of aquatic
life...

• Identify Reference and Impaired Communities.
• Least Impairedfrom areas w/lower nutrients, good
  water clarity
• Identify Phytoplankton Metrics ( Reference vs.
  Impaired)
• Chlorophyll level
• Community composition (e.g. of Cyanophytes)
• Cell size
• Score Stations (1 worst - 5 Best)
• Score metrics (1,3,5)
• Score samples (Avg. of metrics)
• Average all samples for station