What makes stormwater runoff unique in the Los Angeles area?
The runoff area, or watershed, in Los Angeles begins at the 3,000 foot level in the San Gabriel Mountains and discharges into the Santa Monica and San Pedro Bays 51 miles downstream. What makes this problematic is that nearly most of the area in between is paved surface, not natural open space. Because there is no opportunity for this rain to infiltrate into the soil and be absorbed into the underground water table, this stormwater picks up every type of pollutant found on city streets and turns the flood control channels into raing torrents. In comparison, the Mississippi River drops 1,463 feet over a distance of 2,348 miles!
