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 Additional studies on urban runoff monitoring have been conducted (Marsalek and Schroter,
1984; Bannerman et al., 1983; Marsh 1993). Line et al. (1997) monitored storm runoff from 20
industrial sites including a chemical remanufacturer, furniture manufacturer, junkyard, landfill, metal
fabricator, paint manufacturer, scrap and metal recycler, textile manufacturer, vehicle maintenance
facility, and wood preserver. Characterization of these sites is given in Table 1.1.9. Table 1.1.10
shows the concentration of metals in industrial runoff from industrial sites and the concentration of
conventional water quality parameters in industrial runoff is shown in Table 1.1.11.
1.1.3.2 Forestry
An undisturbed forested watershed delivers very small quantities of nutrients and little sediment
to waterways.
Nutrient concentrations from the undisturbed forest are generally termed the uncontrollable
background concentrations.
Deforestation and other vegetative removal has been shown to increase sediment and nutrient
loading in a watershed. Phosphorus, in particular, is strongly associated with soil particulate matter. The
removal of vegetative cover promotes erosion and increases both the sediment and phosphorus load in
nearby aquatic systems. Terrestrial vegetation contains a large nutrient pool in some ecosystems. The
destruction of this vegetation can release the stored nutrients, and make them available for leaching or
runoff.
Forest practices such as roadbuilding and harvesting trees can result in erosion and sediment
delivery to streams. Soil erosivity and slope are important factors that affect soil loss and sedimentation.
Maintaining a streamside buffer zone is an important water quality practice. The buffer zone can reduce
the transport of nutrients and sediment to streams and also provide habitat for fish and wildlife.
1.1.3.3 Agriculture
Agricultural practices can be important nonpoint sources of nutrients. Nitrogen and phosphorus
fertilizers can be applied in large quantities to many croplands. Under poor management they can
contribute to the nutrient load of the basin. Commercial feedlots and other intensive animal production
facilities also produce wastes of high nutrient content, which often enter waterways via surface or
subsurface flow.
1.1-32
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