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<br />STORMWATER QUALITY MANAGEMENT
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<br />DRAINAGE CRITERIA MANUAL (V. 3)
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<br />3. Stream Qualitv: Water quality is impacted through urbanization, mostly by sediment, as a result cf
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<br />erosion during construction, addition to changes In stream morphology, and washing off of
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<br />accumulated deposits. Water quality problems include turbid water, nutrient enrichment, bacterial
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<br />contamination, organic matter loads, metals, temperature increases and increased trash and
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<br />debris.
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<br />Table 1.1 lists the common.parameters and their Impacts.
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<br />TABLE 1.1
<br />Urban Runoff Pollutants
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<br />Parameters
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<br />Sediments- TSS, Turbidity,
<br />dissolved solids
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<br />Nutrients-Nitrate, Nitrite,
<br />Ammonia, Organic Nitrogen,
<br />Phosphate , Total Phosphorus
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<br />Pathogens-Total and Fecal
<br />Coliforms, Fecal Streptococci
<br />Viruses, E.Coli, Enteroccus
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<br />Organic Enrichment-BOD,
<br />COD, TOC and 0,0,
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<br />Toxic Pollutants-Metals,
<br />Organics
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<br />Salts-sodium chloride
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<br />Sources
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<br />Construction sites
<br />Urban/agricultural runoff
<br />Landfills, septic fields
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<br />Lawn/Agricultural runoff,
<br />Landfills, Septic fields,
<br />Atmospheric deposition, erosion
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<br />Urban/Agricultural Runoff Septic
<br />Systems, Illicit sanitary
<br />connections, domestic/wild
<br />animals
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<br />Urban/Agricultural Runoff,
<br />Landfills septic systems
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<br />Urban/Agricultural Runoff,
<br />Pesticides/Herb icides,
<br />Underground storage tanks,
<br />Hazardous Waste Sites,
<br />landfills, illegal disposals,
<br />industrial discharges
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<br />Urban runoff snowmelt
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<br />Effects
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<br />Habitat changes, stream
<br />turbidity, recreation and
<br />aesthetic loss, contamnant
<br />transport, bank erosion
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<br />Algae blooms, Ammonia
<br />Toxicity, Nitrate Toxicity
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<br />Ear/Intestinal infections,
<br />Shellfish bed closure,
<br />Recreation/aesthetic loss
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<br />Dissolved oxygen depletion,
<br />odors, fish kills
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<br />Toxicity to humans and aquatic
<br />life, bioaccumulation in the
<br />foodchain
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<br />Contamination of drinking water,
<br />harmful to salt intolerant plants
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<br />Source: Handbook: Urban Runoff Pollution Prevention and Control Planning, 1993.
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<br />These changes result in stress on aquatic life which include:
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<br />1. A shift in the aquatic plants from leafy plant to more algal organic matter. This results in a change
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<br />in water chemistry such as changes in the pH and dissolved oxygen levels, The change may also
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<br />impact the food source for aquatic animals
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<br />2. A reduction in diversity in the stream community.
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<br />SQ.2
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<br />X-X-98
<br />Urban Drainage and Flood Control Dlstr ct
<br />DENilg15~l9 docJ982720004.DC'C
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