Effects of Nutrient Enrichment on Rivers and Streams

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Effects of Nutrient Enrichmenton Rivers and
Streams
Ohio EPA 2006
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Mandate to Restore Polluted Waters
FEDERAL WATER POLLUTION CONTROL ACT As Amended
Through P.L. 107303, November 27, 2002
SEC. 101. (a) The objective of this Act is to
restore and maintain the chemical, physical, and
biological integrity of the Nations waters.
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Leading Causes of Impairment2000 Ohio Water
Resources Inventory
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Effects of Nutrient Enrichment On Streams

• Increased Algae Growth
• Wide Swings in Dissolved Oxygen
• fish need at least 4.0 mg/l
• Simplified Biological Communities
• fewer types of fish and bugs but more of them
• fish kills
• Habitat a Strong Modifier
• Shading, Assimilative Capacity

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Habitat Destruction and Nutrient
EnrichmentEffects on Stream Fish Community
Healthy Fishery
Degraded Fishery
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Good Habitat(Shading, Better Nutrient
Processing, More Living Places)
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Poor Habitat(Full Sunlight, Boom and Bust
Production, Fewer Living Spaces)
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Historic Range of Smallmouth BassTrautmans
Fishes of Ohio
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Viable Smallmouth Bass Fisheries
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Nutrient StudySampling Locations 2004 2005
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Findings from Nutrient Study2004 2005
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D.O. Swings As Related to TP and Canopy
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Gross Nutrient EnrichmentStillwater River
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Buffers and Habitat Quality
Bank erosion
Nothing here to filter pollution
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Landuse and Nutrient Enrichment
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Average Phosphorus Concentrations Around Ohio
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Stream Quality and Density of CAFOs
Mercer
Auglaize
Darke
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Managing the Landscape to Manage Nutrient Loads

• Streams need wide buffers
• provide shading
• cooler temperature
• limit algae growth
• filter pollutants
• allow sediment to drop out
• vegetation take up nutrients
• accidents do happen, need margin of safety
• Good Physical Habitat
• increase processing of nutrients
• where drainage needed, use natural channel
  designs
• Wetlands or Riparian for Tile Drainage
• tiles by-pass riparian zone