In 2008, Metro Vancouver and Engineers Canada cooperated in the Vancouver Sewerage Area (VSA) vulnerability assessment. The VSA study was one of seven original pilot study applications of an assessment protocol developed by Engineers Canada for use with all types of infrastructure across Canada. That study focused on an area that is largely combined (i.e. sanitary sewage and stormwater conveyed in the same pipe) and currently undergoing significant change through an ongoing program of sewer separation (i.e. separating stormwater and sanitary sewage into different pipes). The Fraser Sewerage Area (FSA) study is a logical extension of the work done in the VSA study and it provides Metro Vancouver with new findings relevant to separated sanitary sewer systems.