WQCP Process Capacities
62 mgd (Headworks Capacity)
40 mgd (Secondary Treatment Capacity)
35 mgd (Effluent Pumping Capacity)
0 10
20 30
40 50
60 70
80 90
0 12 24 36 48 60 72
Flow (mgd)
Time (hours)
10-Year 24-Hour Base Storm
10-Year 24-Hour (20% I/I Reduction)
10-Year 24-Hour (40% I/I Reduction)
Figure 7.6
Future WQCP PWWF
(10-Year 24-Hour Design Storm)
City-Wide Sewer System Master Plan
City of South San Francisco
LEGEND
August 20, 2020
Headworks Capacity (62 MGD)
Secondary Treatment (40 MGD)
Effluent Pumping (35 MGD)
8.71 8.23
5.04 4.18 3.44
3.42 3.31 3.38 3.28 3.28
3.79 3.41
1.86 1.84
1.61 1.46
1.44 1.54 1.52 1.47 1.53 1.45
1.53 1.37
11.90 8.61
3.78 2.72
0.00 0.10 0.00
0.00 0.22 0.33
2.91 0.12
0.00 5.00
10.00 15.00
20.00 25.00
30.00 35.00
0.00 40.00
2.00 4.00
6.00 8.00
10.00 12.00
14.00 16.00
Jan-18Feb-18Mar-18Apr-18May-18Jun-18Jul-18Aug-18Sep-18Oct-18Nov-18Dec-18 Precipitation (inches)
South San Francisco Flows (mgd)
August 2, 2019
Figure 5.1
2018 WQCP Flows
City-Wide Sewer System Master
Plan
City of South San Francisco
Monthly
Rainfall
WQCP Flows
LEGEND
Note: Monthly flows shown exclude San Bruno
2018 Average Flow
West of 101 Monthly Flows
Monthly Rainfall
East of 101 Monthly Flows
Average Annual Flow: 6.01 mgd
Table 5.2 Historical Flow Statistics (West of 101)
City-Wide Sewer System Master Plan
City of South San Francisco
Seasonal Average Monthly Average Maximum Day
ADWF AWWF PMDWF PMWWF MDDWF MDWWF
(mgd) (mgd) (mgd) (mgd) (mgd) (mgd) (mgd)
Historical Flows
2012 4.48 3.91 4.89 3.95 6.71 5.30 18.92
2013 3.88 3.81 3.94 3.91 4.31 5.76 6.56
2014 4.31 3.88 4.63 3.95 7.51 5.38 25.25
2015 3.73 3.43 3.95 3.47 4.41 4.57 12.57
2016 4.19 3.54 4.65 3.62 5.99 4.43 15.17
2017 4.43 3.36 5.20 3.44 8.71 4.70 24.52
2018 3.89 3.57 4.12 3.67 4.60 4.76 19.21
Historical Peaking Factors (Applied to ADWF)
2012 1.15 1.00 1.25 1.01 1.72 1.36 4.84
2013 1.02 1.00 1.03 1.03 1.13 1.51 1.72
2014 1.112 1.00 1.19 1.02 1.94 1.39 6.51
2015 1.088 1.00 1.15 1.01 1.29 1.33 3.66
2016 1.183 1.00 1.31 1.02 1.69 1.25 4.29
2017 1.318 1.00 1.55 1.02 2.59 1.40 7.29
2018 1.089 1.00 1.15 1.03 1.29 1.33 5.38
Recommended Evaluation Peaking Factor
1.30 1.03 2.00 1.40 6.50
2/26/2020
Notes:
1. Historical flows extracted from WQCP data received from City staff June 19, 2019.
2. Dry weather months include months from May to September.
3. Wet weather months include months from October to April.
4. Flows for the City of San Bruno are not included in the historical flows and were estimated based on Pump Station 11 inflows and flows recorded at Flow Monitor 7. An analysis of these flows indicated approximatley 80% of the flows at Pump Station 11 are contributed by the City of San Bruno.
Year Average Annual
Table 5.3 Historical Flow Statistics (East of 101)
City-Wide Sewer System Master Plan
City of South San Francisco
Seasonal Average Monthly Average Maximum Day
ADWF AWWF PMDWF PMWWF MDDWF MDWWF
(mgd) (mgd) (mgd) (mgd) (mgd) (mgd) (mgd)
Historical Flows
2012 1.63 1.56 1.67 1.60 1.88 1.96 3.16
2013 1.61 1.62 1.61 1.67 1.66 1.96 1.97
2014 1.63 1.58 1.67 1.61 1.94 1.89 3.17
2015 1.57 1.56 1.57 1.62 1.64 1.91 2.18
2016 1.52 1.43 1.58 1.45 1.74 1.70 2.37
2017 1.55 1.50 1.59 1.54 1.86 1.82 2.99
2018 1.34 1.27 1.40 1.31 1.53 1.53 2.48
Historical Peaking Factors (Applied to ADWF)
2012 1.04 1.00 1.07 1.02 1.20 1.25 2.02
2013 1.00 1.00 1.00 1.03 1.03 1.22 1.22
2014 1.03 1.00 1.06 1.02 1.23 1.20 2.01
2015 1.00 1.00 1.00 1.04 1.05 1.22 1.39
2016 1.06 1.00 1.10 1.02 1.22 1.19 1.66
2017 1.03 1.00 1.06 1.03 1.24 1.22 1.99
2018 1.06 1.00 1.10 1.03 1.20 1.20 1.95
Recommended Evaluation Peaking Factor
1.10 1.04 1.25 1.25 2.00
2/26/2020
Notes:
1. Historical flows extracted from WQCP data received from City staff June 19, 2019.
2. Dry weather months include months from May to September.
3. Wet weather months include months from October to April.
Year Average Annual