HomeMy WebLinkAbout06.a.2) Receive 2015 Collection System Sanitary Sewer Overflow Annual Report (PowerPoint)a.z)
ANNUAL REPORT OF SANITARY
SEWER OVERFLOWS
Ann K. Sasaki
Deputy General Manager
Collection System Operations Division
March 3, 2016
2015 SANITARY SEWER OVERFLOWS
• 43 Overflows
• 2.83 per 100 Miles
• No Pumping Station or Capacity Overflows
COMPARATIVE DATA FOR 2015
FROM STATE DATABASE
Number of
Overflows
Total Volume
(Gallons)
Average per
100 Miles
Average Volume
per SSO (Gallons)
3,936 926
16,748,874 639,760
4.4 5.5
4,255 691 2,074
43
89,172
2.83
*Info from CIWQS as of 1/22/2016
40 •
OVERFLOWS COMPARISON 1999-2015
NUMBER OF OVERFLOWS
180 -
160 -
140 -100
120-
100 __.
80
60-
40 �.'�,;
20 r(: �.
143 14
162
135
123
107
81 86
73
63
43
37
49 48 49
0
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015
OVERFLOW QUANTITIES
Greater Than or Equal
to 1,000
Between 100 and 999
3
16
4
16
Between 10 and 99 28 18
Less Than 10 2 5
Total Overflow Volume 13,501 Gallons 89,172 Gallons*
*The SSO that occurred on July 13, 2015, was 71%
(63,131 gallons) of the total volume.
11 1in
7 11
2015 OVERFLOW BY CITY AND CAUSE
Walnut Creek
Pleasant Hill
Orinda
Moraga
Martinez
Lafayette
Danville
Alamo
4
1
1
1
0 4 8 12 16 20
0 Roots
Number of Overflows
o Grease
®Rags/Rock/Paper/Debris °Other Plug
2015 OVERFLOW CAUSES
9%
9%�:�, ,�.�' ■ Roots
Grease
Rags/Rock/Paper/Debris
■ Other Plug
2015 OVERFLOWS
BY PIPE SIZE, TYPE, AND CITY
15
12
9
6
3
0
71
Alamo Danville
Lafayette
1
Martinez
Moraga
6
Orinda Pleasant Hill Walnut Creek
■6" ABS ❑8" ABS ❑8" AC ❑6" ACP ■8" ACP 06" DIP ■6" HDP 08" PVC 06" VCP ■8" VCP ■10" VCP
CATEGORY 1 OVERFLOWS
(ANY VOLUME OF WASTEWATER THAT REACHES THE WATERS OF THE STATE)
Updated through December 2015
1 Year: 2011 2012 2013 2014 2015
Total 0/Fs by year: 4 8 1 1 5
YTD comparison: 4 8 1 1 5
JAN 0 0 0
FEB 0 0 0
MAR 0 1 0
APR 0 1 0
MAY 0 0 0
JUN 2 0 0
JUL 0 0 0
AUGI 1 1 01
SEPI 1 0 01
OCT 0 3 0
NOV 0 1 1
DEC 0 1 0
0 0
0 1
0 1
0 0
0 1
0 0
0 1 4
0 0
0 0 3
0 0
0 1 2
1 0
9
8
7
6
5
1
0 t ■ MENNEN
JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC
-,, 2011 -F 2012 -fir 2013 -M-2014 2015
CSO HIGHLIGHTS
• Cleaned 850 miles of sewers.
• CCTV'd 180 miles of sewers.
• Completed 64 spot repairs and 198 structure adjustments.
• Accomplished over 20,900 cleaning schedules and work
orders that were completed on schedule 99% of the time.
• Received and cleared over 22,800 USA requests on time.
• Completed 975 services on vehicles and equipment. DOT
regulated services were completed on schedule 100% of the
time. Up time for vehicles was greater than 95%.
CSO CUSTOMER SERVICE
• Conducted survey of 100% of all customer emergency calls.
• 256 customer surveys were sent to ratepayers. 83 surveys
were submitted for a return rate of 32%.
• Average customer service rating was 3.81 out of 4.0.
• Received a rating of 4.0 for 3 months of the year.
• Average response time was 36.6 minutes.
Questions?