Urban development has changed the landscape across the country, affecting everyone, but benefiting only some. This excludes salmon, who are sensitive to even the slightest changes in their environment, and have had it upset a great deal. There are several primary components to Urban development to which destroying salmon habitat can be attributed to. Construction work of any kind causes erosion which creates sediments that fill up spaces between gravel and rocks salmon use to lay their eggs in. Sediment also fill pools which are used to spawn, rest, avoid temperature fluctuations, and drastic changes in speed of the river flow. Not to mention, since sediment pollutes water as smog and other substances pollute our air, it causes damage to the gills of salmon. Urban development also introduces impervious or solid surfaces such as sidewalks, parking lots, roads, and houses to salmon habitat. This prevents melting snow and water from soaking into the ground. Instead it collects, especially during storms, and increases the volume and speed of the nearby river. Unfortunately, this runoff is not limited to water. Sewage, industrial waste, gas, oil, chemicals, and lawn fertilizers are just a handful of the pollutants that flow from storm drains in urban areas into local rivers and streams, unfiltered.
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