City of Morgan Hill Sewer System Master Plan 2017

City of Morgan Hill Sanitary Sewer Flow Monitoring and Inflow/Infiltration Study

Design Storm Response Summary The 10-year, 24-hour storm event was applied to the synthetic I/I hydrograph components developed for each flow monitoring site. This method produces the best estimated response to the design storm events. These results assume full ground saturation and that the peak I/I flows from the design storm coincide with peak sanitary flows to produce a “worst-case” scenario of peak wet weather flows. Table 13 summarizes the final results for the design storm on a site-by-site basis.

Table 13. Design Storm I/I Analysis Summary

Predicted Peak Dry Weather Flow (mgd)

Predicted Peak I/I Rate (mgd)

Predicted Peak Flow (mgd)

Metering Site

Predicted Total I/I (gallons)

0.34 0.58 0.56 0.37 1.89 0.67 0.38 0.29 0.25 0.24 4.46

0.75 1.42 3.13 1.02 5.26 1.22 2.41 0.70 1.16 0.14 8.74

1.09 2.00 3.69 1.39 7.15 1.89 2.80 0.99 1.40 0.39

285,000 451,000

Site 1 Site 2 Site 3 Site 4 Site 5 Site 6 Site 7 Site 8 Site 9

1,134,000

279,000

2,128,000

468,000 749,000 214,000 371,000 52,000

Site 10 Harding

13.20

4,075,000

12-0248 AEG CofMorganHill FM Rpt.docx

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