Comprehensive Sewer Plan Update, Midway Sewer District

Des Moines


Midway Sewer District is expected to experience significant population growth due to the expansion of SeaTac International Airport and the Sound Transit light rail system.  BHC converted the District’s existing spreadsheet hydraulic model to an InfoSWMM dynamic model. The updated model, combined with updated population and employment productions was used to develop a 6-year and 20-year capital improvement program that will allow the District to serve its rapidly growing customer base while maintaining some of the lowest sewer rates in Washington State.


  • Updated truncated spreadsheet model to dynamic InfoSWMM model
  • Updated and improved reliability of population and employment projections
  • Developed reliable and defensible CIP
Back to all Projects