Geoscience Reference
In-Depth Information
10.00
Industry Area
Residence
Roads
1.00
0.10
0.01
0.00
Zinc
Nickel
Iron
Chrome
Copper
Barium
Lead
Aluminum
Heavy Metal
Fig. 5.6 Heavy metal concentrations in urban storm water (mg/L) from various land uses
5.5.3 Calculation of Mass Pollutant Loads from Various
Land Uses
Figure
5.8
shows the flax loads calculated in mass/unit of area/year in the various
basins. In this calculation the appropriate runoff coefficient was taken into
account for each basin and the average concentrations representing all the
rainstorms sampled. This calculation makes it possible to compare values
received from various land uses per unit of area. It can be seen that in this case
there is greater significance in the different loads received from industrial areas
as compared with residential areas. There difference in order of magnitudes for
some of the elements such as potassium zinc, chloride and magnesium. From the
calculation of the loads it can be seen that the Ra'anana industrial basin
contributes more salts and metals per unit of area than the Herzliya industrial
basin. In the industrial areas, the runoff coefficients were higher, as were the
average concentrations, and therefore, there was a more significant contribution
from these watersheds per unit areas. These coefficients can give threshold values
for the contribution of pollutants from urban areas in Israel and can be used for
a preliminary calculation of the loads reaching streams or the sea from urban
areas along the coastal plain of Israel.
