Stormwater runoff in storm drains is difficult to monitor because of its intermittent and highly variable nature. An alternative to discharge sampling, for screening for contamination, is in-line sediment sampling from low energy sections (manholes and shallow-sloped lines) of the drainage system. The Puget Sound Urban Bay Action Program for Elliott Bay has developed a four-phased monitoring approach for tracing contaminants and identifying sources of toxic contaminants in storm drain systems: compilation of available information to define the storm drain system, drainage basin characteristics and conditions in the receiving environment; collection of in-line sediment samples near the mouths of storm drains to identify contaminated drainage systems; selection of problem drains for further intensive inspection and conducting sampling activities to trace contaminants and identify the ultimate sources of contamination; confirmation of contaminant contributions from individual sources and identification of sources by collecting water samples from side drain connections that discharge into the storm drain. The results from one phase determine the necessary actions in each successive phase.

Cover title. "June 1988." "TC 3338-23. Task 5." "Final report. "Puget Sound Estuary Program."--At head of title. Includes bibliographical references.