City of Morgan Hill Sewer System Master Plan 2017

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

Combined I/I Results Summary Combined I/I analysis considers the totalized volume (in gallons) of both inflow and rainfall-dependent infiltration over the course of a storm event. Table 12 summarizes the combined I/I flow results for the storm event (refer to the I/I Methods section for more information on combined I/I analysis methods and ranking methods). Basins that ranked 1, 2 or 3 in a category are color coded red.

Table 12. Basin Combined I/I Analysis Summary

Combined I/I (gallons)

Overall Combined I/I Ranking A

Metering Basin

ADWF (mgd)

R-Value (%)

Combined I/I per ADWF

0.13% (6) B 0.10% (8) 1.00% (1) 0.26% (3) 0.22% (4) 0.12% (7) 0.63% (2)

Basin 1 Basin 2 Basin 3 Basin 4 Basin 5 Basin 6

0.19 0.17 0.18 0.21 0.27 0.35 0.40

56,400 47,200 166,200 114,100 90,900 136,300 230,300

0.15 (7) 0.15 (8) 0.52 (1) 0.27 (4) 0.18 (6) 0.18 (5) 0.33 (3)

7 8 1 4 5 6 2

Basin 7/8

Basin 7 Basin 8

0.24 0.16

177,700 52,000

1.31% 0.23%

0.42 0.19

Basin 9 Basin 10 System

0.13 0.12 2.65

133,300 16,400

0.22% (5) 0.06% (9)

0.49 (2) 0.06 (9)

3 9

1,135,500

0.23%

0.22

A Ranking of 1 represents most inflow after normalization. B The number in parenthesis shows the ranking within the individual Category.

The following combined I/I analysis results are noted:  Basins 3, 7/8, 9 and 4 ranked highest for normalized combined I/I contribution. ♦ If isolated, Basin 7 ranks highly within the Basin 7/8 basin and highly within the collection system.

Figure 29 shows bar graph summaries of the combined I/I analysis. A temperature map by overall ranking is shown in Figure 30.

12-0248 AEG CofMorganHill FM Rpt.docx

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