Strategies aimed at managing storm water quality are a relatively recent development.
As a result, any discussion of the various storm water management strategies can only give approximate ranges of pollutant removal capabilities. New technologies or strategies for water quality control are likely to develop which will require the modification of, or make obsolete, strategies that are currently being utilized. On-going monitoring, not only of the direct storm water runoff, but also the effects on receiving waters, humans, vegetation and aquatic life is being conducted to determine the long term cost effectiveness of the structural control measures selected, and any future revisions that might be necessary. Storm water treatment controls, unlike source controls, are often high cost items that will require extensive long term maintenance. Implementation of storm water management concepts must also conform to the policies set forth in the Caltrans Storm Water Management Plan.