October 2008, Vol. 20, No.10

Sewer Sociology

Mystery Flow: Part 6

Kevin L. Enfinger and Patrick L. Stevens

 

 

sew´•ẽr sō•ci•ol´ō•gy, the science of society, social institutions, and social relationships viewed through the eyes of a sewer; specifically, the systematic study of the development, structure, interaction, and collective sewer use of organized groups of human beings.


Most sewer flows are characterized by repeatable diurnal patterns that vary across weekdays, weekends, and holidays. Differences in land use are also apparent. During the past 5 months, we have put your sewer sociology skills to the test with mystery land-use patterns. The challenge concludes this month with our sixth and final mystery flow installment.

A composite hydrograph of flowmonitor data from a location in the northeastern United States is provided in the figure. Weekdays are shown in green, and weekends are shown in light blue. Weekday flows show considerably more activity than weekend flows — beginning about 6 a.m. and ending about 5 p.m.


Mystery Land Use Area
Figure 2. Mystery Land-Use
Click figure for larger view>


Based on this information, which of the following do you think this mystery land-use pattern is?

a) An automobile assembly plant.
b) A national monument.
c) A political convention.
d) A stock exchange.

Think you know the answer? To enter our contest, click here and select the answer you think best describes this month’s mystery flow. Responses will be accepted until Oct. 31. The winner, who will be drawn at random from those submitting correct responses, will receive a WE&T prize pack. Good luck!


 

Mystery Flow: Part 5 Revealed

Last month’s mystery land-use pattern was obtained downstream from a mental health hospital in the Pacific Northwest. Most patient-care activities occur on weekday mornings. The sewer use pattern of a more traditional hospital is provided for comparison.

Mystery Flow Part 5 Revealed Oct 2008
Click figure for larger view


Mystery Flow: Part 4 Winner

Congratulations to Rebecca Lewis of Wichita, Kan., who correctly identified the land-use pattern in Mystery Flow: Part 4 as a “big box” retail store.

 

Kevin L. Enfinger is senior project engineer, and Patrick L. Stevens is vice president of engineering at ADS Environmental Services, a division of ADS LLC (Huntsville, Ala.).