Engineering and economical comparison of the surface runoff disposal options

Summary

The results of an engineering and economical comparison of two surface runoff disposal options are presented. Option 1 involves the use of treatment facilities discharging the effluent into a water body; option 2 involves the use of a storage tank followed by the discharge of surface runoff into a public sewer. The comparison was based on life-cycle costs over a 25-year operational period for new construction of treatment facilities with a capacity of 250 m³/h and storage tanks with a capacity of 6,000 m³. Option 2 involving surface runoff discharge into a public sewer, was determined to be the most cost-effective, with an economic efficiency of 214.75 mln rubles. This 46.59% economic efficiency is achieved by reducing capital expenditures. Furthermore, one of the main expenditure items is the sewer user fee that virtually offsets the difference in operating costs.

Key words

surface runoff , treatment facilities , life cycle cost , storage settling tank , domestic wastewater disposal system