1. APRIL 30, 2012 PRESENTATION
AT DISCOVERY WORLD
BY ZAFAR YOUSUF, P.E.
SEWER DESIGN MANAGER
CITY OF MILWAUKEE
City of Milwaukee, Environmental 1
Engineering

2. CITY-MMSD PARTNERSHIP
 CITY-MMSD PARTNERSHIP TO
IMPLEMENT I/I REDUCTION
PROJECT
 IN THE AREA BOUNDED BY:
N. 82nd ST. TO N. 92ND ST. FROM
W. CENTER ST. TO W. BURLEIGH
ST.
City of Milwaukee, Environmental 2
Engineering

3. CITY BACKGROUND
 THE CITY HAS 96 SQUARE MILES AREA,
WITH ABOUT 600,000 POPULATION AS PER
2010 CENSUS DATA
 THERE ARE 940 MILES OF SANITARY
SEWERS IN THE CITY COMPRISING OF
ABOUT 850 SYSTEMS.
 A SANITARY SYSTEM IS DEFINED WHERE A
CITY SEWER MAIN NETWORK CONNECTS
DIRECTLY TO THE MMSD’S OWNED AND
MAINTAINED METROPOLITAN INTERCEPTOR
SEWER (MIS)
City of Milwaukee, Environmental 3
Engineering

4. I/I in the City of Milwaukee
 Systems are monitored to compare sanitary base flow
to peak flows during rain events
 Based on the data and subsequent modeling, 8% of
sanitary systems showed high levels of I/I and were
determined to be non-compliant by Milwaukee
Metropolitan Sewerage District (MMSD).
* Non Compliant meter sheds are those meter sheds that
exceed the maximum flows established by MMSD's
rules.
City of Milwaukee, Environmental 4
Engineering

5. Where does I/I come from ?
 Cracks in pipes
 Roots thru joints
 Storm Water Inflow
 Sanitary Sewer
Foundation Drain
Connections
 Storm Sewer
Downspout
Connections City of Milwaukee, Environmental
Engineering
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6. Area Bounded by:
N. 82nd St to N. 92nd St from
W. Center St to W. Burleigh St
City of Milwaukee, Environmental 6
Engineering

7. I/I Investigation
 Non-Compliant
Dye Flooding Video
sanitary sewer system
Examination
showing high levels of
I/I were dye tested
 The storm sewer was
flooded with dye and
the sanitary sewer
was examined
 Dye testing Results
showed private
laterals as a source of
75% of the I/I City of Milwaukee, Environmental
Engineering
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8. Why was this area chosen?
 This area was identified by the Wisconsin Department of Natural
Resources (WDNR) and the Milwaukee Metropolitan Sewerage
District (MMSD) as having high levels of Inflow and Infiltration (I/I)
26-times base flow
24-times base flow
City of Milwaukee, Environmental 8
Engineering

9. I/I Demonstration Project
 This project consists of inspecting and rehabilitating the
sanitary building sewers (laterals) of homes
 This program was 100% voluntary and homeowners will
not incur any costs
 This area has reported numerous basement backups over
the last few years
City of Milwaukee, Environmental 9
Engineering

10. SANITARY SYSTEM INFORMATION
 THIS SYSTEM IS COMPRISED OF APPROXIMATELY
18,500 FEET OF 8-INCH TO 12 INCH DIAMETER
SANITARY SEWERS ORIGINALLY BUILT IN THE
1940’S
 ALL SANITARY SEWER MAINS WERE CURED-IN-
PLACE LINED IN 2010
 THERE ARE 70 SANITARY MANHOLES THAT WERE
ALSO LINED IN 2010
 THERE ARE 563 PROPERTIES IN THIS SYSTEM
City of Milwaukee, Environmental 10
Engineering

11. PURPOSE
 REDUCE SANITARY SEWER OVERFLOWS
 REDUCE BASEMENT BACKUPS
 REDUCE MAINTAINANCE COSTS
 REDUCE WASTE WATER TREATMENT
COSTS
City of Milwaukee, Environmental 11
Engineering

12. Project Details
 Letters were sent to all 563 home owners
regarding inspection and rehabilitation of their
sanitary sewer lateral. As of April 24, 2012, 512
home owners , approximately (91%), have
consented for the rehabilitation.
 The City has worked with residents to minimize
disruptions and inconvenience during the project
 Post rehabilitation flow monitoring data will be
compared with pre-rehabilitation data to estimate
the effectiveness that lateral lining has on flow
reduction
City of Milwaukee, Environmental 12
Engineering

13. What is being done?
A 4-Step Process
 1. Sanitary Lateral Inspection
 2. Cleanout Installation
 3. Roof drain dye testing
 4. Lateral Rehabilitation 13
City of Milwaukee, Environmental
Engineering

14. 1. Sanitary Lateral Inspection
 A camera is
inserted in the
lateral from the
sewer in the
street
 The lateral
condition is
assessed for
rehabilitation City of Milwaukee, Environmental
Engineering
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15. 2. Cleanout Installation
City of Milwaukee, Environmental 15
Engineering

16. 2. Cleanout Installation
 A hole is hydro-
excavated as close
to the house as
possible
 A Vac-A-Tee is
installed on the
sanitary lateral
 The hole is then
backfilled to grade 16
City of Milwaukee, Environmental
Engineering

17. VAC-A TEE
City of Milwaukee, Environmental 17
Engineering

18. 3. Roof drain dye testing
A green dye is
pumped into the
roof gutters
A video camera is
inserted in the
sanitary lateral to
detect any dye
leaking in the
sanitary lateral
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Engineering

19. Lateral Rehabilitation
City of Milwaukee, Environmental 19
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20. 4. Sanitary Lateral Rehabilitation
 The existing sanitary Before
laterals were televised
(roots and cracks are evident)
 The sanitary lateral is
rehabilitated with a cured- During
in-place lining method
from the public sewer
main in the street
 The liner is installed to After
the cleanout
City of Milwaukee, Environmental 20
Engineering

21. INSTALLED CONNECTION
City of Milwaukee, Environmental 21
Engineering

22. CURRENT PROJECT STATUS
 512 HOME OWNERS CONSENTED FOR
LATERAL REHABILITATION (91%)
 382 LATERALS HAVE BEEN LINED
(75%)
 PROJECT COMPLETION DATE IS MAY 25
City of Milwaukee, Environmental 22
Engineering

23. PROJECT COSTS
 TOTAL PROJECT COST=$ 3.8 MILLION
 MMSD ALLOCATED FUNDS= $ 3.4
MILLION
 CITY FUNDS= $ 0.4 MILLION
(In addition, city spent $ 600,000 for mainline lining)
 AVERAGE COST PER HOME=$ 7,700
City of Milwaukee, Environmental 23
Engineering

24. COST BREAKDOWN
 TV CAMERA INSPECTION-$ 5 PER LIN. FT.
(Average lateral length 60 lin. ft per home)= $ 300
 LATERAL TRACING- $ 200 EACH
 CLEAN OUT- $ 1,600 EACH
 ROOF DRAIN DYE TEST- $ 200
 LATERAL LINER INSTALLATION
$ 80 PER LIN. FT x 60 = $ 4,800
City of Milwaukee, Environmental 24
Engineering

25. EXAMPLES OF OTHER CITIES DOING SUCH
PROJECTS
 CITY OF NEW CASTLE, DELAWARE REDUCED ITS
TOTAL FLOWS BY 73 PERCENT IN A SANITARY
BASIN*
 ACHIEVED A 55 PERCENT REDUCTION IN PEAK FLOW
RATES OF THE SANITARY BASIN*
* TO JUDGE THE REHABILITATION EFFECTIVENESS,
PRE-REHABILITATION FLOWS WERE COMPARED WITH
POST-REHABILITATION FLOWS
City of Milwaukee, Environmental 25
Engineering

26. EXAMPLES OF OTHER CITIES DOING SUCH
PROJECTS
 CITY OF NAPERVILLE, ILLINOIS REDUCED ITS TOTAL
YEARLY FLOW TO THE TREATMENT PLANT BY 192
MILLION GALLONS IN ONE YEAR
 THEY ACHIEVED THIS BY LINING 65 MILES OF
SANITARY MAIN LINES AND REHABILITATING 3,000
LATERALS SINCE 2002
 DOING SUCH IMPROVEMENTS ALLOWED THEM TO
DEFER CONSTRUCTION OF A NEW TREATMENT PLANT
City of Milwaukee, Environmental 26
Engineering

27. Our Goals
 Reduce chances of sanitary sewer overflows and
basement backups during heavy rain events
 Reduce the maximum amount of I/I in the sanitary
sewer system
 Judge the rehabilitation effectiveness by analyzing
pre-rehabilitation flows with post- rehabilitation flows.
 Improve public health and the overall quality of life in
the City
City of Milwaukee, Environmental 27
Engineering

28. Follow up
 A post rehabilitation survey
was sent to all residents for
comments and concerns
regarding the project
 To date, approximately
95% of responses have
been positive regarding the
project (50% response
rate)
City of Milwaukee, Environmental 28
Engineering

29. USEFUL WEBSITES
 MILWAUKEE METROPOLITAN SEWERAGE
DISTRICT (MMSD)
 http://basementconnection.mmsd.com/
 PRIVATE PROPERTY VIRTUAL LIBRARY (PPVL)
 http://www.wef.org/PrivateProperty/
 LMK ENTERPRISES, INC.
http://www.performanceliner.com/
City of Milwaukee, Environmental 29
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30. QUESTIONS
?
City of Milwaukee, Environmental 30
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