&EPA
United States
Environmental Protection
Agency
CASE STUDY
Clearwater, FL Abates
Sanitary Sewer Overflows
Using the EPA Region 4
Management, Operations
and Maintenance Approach
Overview
Public sewer utilities in EPA
Region 4 have been asked to
implement management, operation
and maintenance (MOM) programs.
Participating municipalities complete self-
assessments of their utilities and submit
recommendations for improvements
to the Region, along with prioritized
implementation schedules. MOM project
successes in Region 4 have contributed
to national development of the
capacity, management, operations, and
maintenance (CMOM) approach.
The City of Clearwater joined the
program in 1998 and submitted its MOM
Plan in 1999. An early benefit of the self-
assessment was identification of needed
maintenance program improvements that
were phased in starting before the Mom
Plan was complete, moving the City from
a reactive to a proactive maintenance
approach. As a result, the number of
sanitary sewer overflows began to
decrease substantially within the first
year.
Clearwater is continuing to improve
maintenance planning and operations as
the Mom Plan implementation progresses.
Other Plan elements include a sewer
system evaluation survey, a flow model
to identify sewer capacity problems, and
a capital improvement plan. Because of
its investment in self-assessment and planning,
the need for future capital improvements to its
implement a needed rate increase.
Clearwater Fast Facts
Population
• 108,000
• 359 miles of gravity sewer and
35 miles of force main
Number of Manholes
• 8,330 manholes and cleanouts
Number of Pump Stations
• 78
Major Program Achievements to
Date
• Backups and pump station
failures reduced by 40%
• Proactive maintenance
increased by 65%, while reactive
maintenance decreased by 35%
Clearwater was able to demonstrate
system, convincing City leaders to
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Background
Clearwater is located in central Florida within the
Tampa Bay Estuary, adjacent to the Gulf of Mexico.
This location is famous for its recreational resources,
including sandy beaches and natural island parks.
It also presents many problems for sanitary sewer
systems, with both significant annual rainfall and
extremely flat topography. In an average year, Clearwater gets
more than 54.5 inches of rain, most falling during the rainy season
from June to November. The topography varies from sea level to 100
feet over the 35-square-mile service area of the sanitary sewer system.
Serving an estimated population of 108,000 with 35,800 service connections, the
sanitary sewer system has 78 pumping stations. The system also consists of 8,330
manholes and cleanouts, along with 359 miles of gravity sewers and 35 miles of
force main. As estimated by the City, 1% of the system consists of items constructed
before 1900,10% between 1900 and 1924, 20% between 1925 and 1949, 28% between
1950 and 1974 with the last 41% of the system elements being less than 25 years old.
Effluent from the sanitary sewer system is treated at three advanced wastewater
treatment facilities with a combined capacity of 28.5 MGD.
City of H
Clearwater
History
EPA Region 4 encourages publicly -owned sewer collection system utilities to perform
a voluntary self-assessment and use the findings to implement a Management,
Operations, and Maintenance (MOM) plan, with an ultimate goal of completely
eliminating sanitary sewer overflows (SSOs). Clearwater was one of the first
communities contacted by the Region to participate in the program, selected based
on its proximity to the federally protected Tampa Bay Estuary. Clearwater agreed to
perform a
seven-month self-assessment in
November of 1998 and completed its
MOM Plan in September 1999.
Before starting its MOM assessment,
Clearwater acted reactively to problems
with the sanitary sewer system. Pump
stations and sewer lines were replaced
and repaired as problems came to light,
but little was done to prevent system
failures before they occurred. Before
1998, sewer lines were only cleaned when
a clog or capacity restriction was found, and no
consistent log of SSOs was kept. During the three-year period from September 1997
to August 2000, Clearwater had a number of SSOs with a total overflow volume of
60,690 gallons. More than 50% of this total volume occurred from September 1997 to
April 1998, during an El Nino period characterized by unusually heavy rains. These
SSOs, ranging in quantity from a few gallons to 30,000 gallons, occurred sporadically
throughout the city. They were caused by a wide variety of problems including
blockages due to grease, infrastructure deficiencies, equipment failures and wet
weather issues.
Offset sewer joints
like this one allowed
inflow and infiltration
into Clearwater's sewer
collection system
during wet weather,
contributing to SSOs.
Photo: City of Clearwater
SSO Case Study—Clearwater, Florida MOM Program
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Pump station
performance has
been improved
through rehabilitation
and regular
maintenance of
pumps and controls.
Photo: City of Clearwater
The City of Clearwater MOM Plan
Clearwater was one of the first municipalities to develop a MOM Program Plan. The
Plan, completed in 1999, describes all three parts of the MOM Program: management,
operations, and maintenance of the sanitary sewer system. In completing the MOM
evaluation, the City developed numerous recommended action items, some of which
have already been implemented.
Pump station maintenance and operation
has always been demanding for Clearwater,
and the source of several large-volume
SSOs. The MOM Plan recommended
development and implementation of a
more structured pump station maintenance
and monitoring program. Clearwater has
provided further funding to the Wastewater
Collection Division, allowing additional
staffing in the department to meet the goal
of visiting and inspecting each pumping
station weekly. The Plan also recommended
that more pump stations be added to the
supervisory control and data acquisition (SCADA) system and that a standardization
plan be developed for all new and rehabilitated pump station projects. The City
used these recommendations to help structure long-term planning for pump station
upgrades and rehabilitation. All new pump station projects will be standardized
following a design developed jointly by Clearwater and pump manufacturers.
SCADA controls will be installed on all significant pump stations (duplex and higher)
as they are rehabilitated.
The MOM
assessment also led
to recommendations
for regular sewer
cleaning. In response,
the City developed a
new cleaning plan that
divided the collection
system into six areas.
As shown on the
map, one area will be
cleaned each year, with
the expectation that
the entire collection
system will be cleaned
every six years. Similar
programs were also
developed for sewer
line inspection (smoke
testing and dosed
circuit television, or
CCTV) and manhole inspedion. Clearwater is developing a geographical information
system (CIS) to track these deaning and maintenance programs.
2003
2004
2005
EH 2006
SSO Case Study—Clearwater, Florida MOM Program
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Improved training and customer service programs were also recommended as part
of the MOM assessment. Clearwater is now documenting its technical and skills
training programs and has created a standard operating procedures manual for
wastewater collection. To help with these training programs, a training position was
created for public utilities in the City. A customer service log was created and a more
proactive approach to grease control is being implemented. A new local ordinance for
grease control has been approved by the City Commission and informational packets
are being used to notify customers in areas with grease control problems.
Sewer System Evaluation Project
As a result of its self-assessment, Clearwater is
performing a comprehensive sanitary sewer
system evaluation (SSES). In the first phase,
Clearwater completed a detailed asset identification
of the system, using the information to create
an operating CIS and an updated system map
with identification numbers for all pipes and
manholes. As of mid-2002,1,450 manholes had
been inspected, 84 miles of gravity sewer had been
smoke-tested, and 109 miles of gravity sewer was
cleaned and inspected with CCTV. Rehabilitation
projects have been implemented to correct defects
identified in these programs.
A capacity analysis model of the interceptor system (all pipes 10 inches and larger)
is also being created as part of the sewer system evaluation. The model will help
identify capacity constraints leading to SSOs in the system based on a 10-year storm
with base flows generated
using the estimated 2020
population.
FEE
By identifying the locations
of capacity constraints
and the estimated volume
of SSOs, the model will
help Clearwater develop
line rehabilitation, flow
balancing, and system
expansion plans. This
analysis, supported by more
than 300 model simulations,
is helping Clearwater assess
the financial and physical
impacts of expected growth
on the sewer collection
system.
Address) http//iseek com/lbe/demo/pinput hlrrj
Pipe Database Input Form for Hydraulic Model
Atlas Sheet Number: |178A
Flow Station ID [0
Scroll to Pipe ID to go to record
for data entry:
POTW ID NORTHEAST
Pipe ID |l78A.m
Upstream MH |1 78A1005
Downstream MH 178A1015
ONLY INPUT DATA BELOW LINE
Upstream Ira. El
Downstream !nv. El.
Pipe Diameter (in)
Pipe Mater
Sediment Depth 2
CCTV inspection and
smoke testing are the
inspection methods
used to identify sewer
defects, sediment
buildup, grease clogs,
and line failures.
Photo: City of Clearwater
Submit | Reset I
System data
are entered
into a GIS
for up-to-date
system maps,
maintenance
activity tracking,
and capacity
analysis
modeling. As shown
in this hydraulic
model input
screen, location
and system ID
information are
retrieved from
the GIS and
supplemented with
model data.
Graphic: TBE Group, Inc.
SSO Case Study—Clearwater, Florida MOM Program
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Line failures and
critical defects
are corrected as
identified, but major
rehabilitation planning
is coordinated with
development of the
SSES and phased
over seven years.
Photo: City of Clearwater
Capital Improvement Planning (CIP)
Collection system improvements are funded through a five-year, 7% annual water and
sewer rate increase. Public support for this rate increase was gained by providing the
city commissioners, city manager, and
citizens with information about the
MOM program and major findings of
the sewer system evaluation.
A preliminary seven-year Capital
Improvement Plan was developed,
which describes how the funds
are expected to be used during the
period. In the CIP cycle ending in
fiscal year 2008, Clearwater expects
to devote 52% of its $11.4 million
annual capital budget to sewer line
rehabilitation and flow-balancing
projects. Preliminary inspection, SSO
tracking, and flow monitoring data have identified several areas of the system
where rehabilitation and flow balancing will likely be needed. Specific plans will be
developed as the SSES progresses.
Another 26% will be devoted to pump station rehabilitation, which is already well
underway. Based on current SSO patterns and modeling of projected future flows, the
78 pump stations have been prioritized for rehabilitation or replacement. The first 24
rehabilitations are underway and should be complete by 2004.
C
apital improvement needs averaging $11.4 million per year are anticipated through 2008. Capital
projects are phased to address the most critical problems first, such as pump station failures and line
relocation and replacement.
Line relocation
and replacement
I/I reduction
10°/c
Pump station
rehabilitation and
SCADA upgrades
System-wide
line rehabilitation
and flow-balancing
SSO Case Study—Clearwater, Florida MOM Program
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First Half
of 2001
Second Half
of 2001
87
Miles of Line Maintained:
^H Proactively
^^ Reactively
Results
Clearwater is tracking a
variety of performance
indicators to monitor
the effectiveness of its
MOM program. In the
first phase of the MOM
program, one of the
primary metrics is the ratio
of reactive to preventive
sewer maintenance-miles
per year. Clearwater realizes
that the aggressive sewer
line cleaning, maintenance
and rehabilitation
program it now pursues
will only help improve
system performance and
control SSOs if the right activities are performed at the right time—before failures
occur. The more effective the maintenance program, the fewer unplanned repairs
will be required. Though it is impossible to prevent all failures, asset management
experts recommend that unplanned maintenance be held to 30% or less of annual
maintenance activities. Emergency and unplanned repairs occurring above that level
can be considered an indication that planning should be revisited to evaluate the
cause of emergencies and adjust maintenance strategies. As the graph at right shows,
in the first half of 2001, the ratio of planned to unplanned maintenance was 33%
to 47%, such that most maintenance was still performed in a reactive mode. By the
end of 2002, the ratio had improved to 86% to 14%, demonstrating that Clearwater's
maintenance planning and performance was well targeted during the period.
The improved maintenance
helped the City achieve
significant improvements
in other performance areas,
including the number of
city-responsible blockages,
pump station failures,
and homeowner cleanup
claims paid. In each of these
areas, Clearwater achieved
reductions that exceeded
initial expectations. The one
performance metric increase
during the period, SSOs,
resulted from better data
tracking, since SSOs were
not routinely recorded prior
to the MOM program.
248
163
Blockages
841
34
I
Overflows
224
56
Pump
60
40
I
Homeowner
Station Cleanup
Failures Claims
2000
• 2001
Overflows not routinely tracked until 2001.
In 2001,
Clearwater
radically reduced
emergency
maintenance by
implementing a
program to clean
and maintain 60
miles of sewer
per year. Planned
maintenance saves
money, prevents
SSOs, and extends
the value of sewer
system assets.
This series of
metrics gives
Clearwater a
better picture of the
effectiveness of the
MOM program. The
City Commission
is kept informed
of the program
performance
indicators, which
are also used to
identify priorities for
additional funding.
SSO Case Study—Clearwater, Florida MOM Program
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Future Plans
The MOM assessment, sewer system evaluation study, and CIP have provided
the future plans for the Clearwater sanitary sewer system. With funding in place,
construction of all of the projects developed in this program will now begin. This
shift in focus from planning to construction moves the implementation of the work
to Clearwater's Engineering Department. The Engineering Department has allocated
five staff engineers to Public Utilities Department needs, and the Public Works
Construction Services Department will dedicate construction inspectors to effectively
administer programs and projects. Plans to update the GIS system as construction
occurs are also underway. An innovative program that allows workers to edit the
sanitary sewer system GIS while in the field is being tested and will be used in the
future.
For More Information on the City of Clearwater
Public Utilities
1650 N. Arcturus Avenue Building #C
Clearwater, FL 33765-1945
Phone: (727) 562-4960
Fax: (727) 562-4961
Internet: http://www.dearwater-fl.ccrn/GtyJI^arta
For Program Information on SSO Abatement
Water Permits Division
U.S. Environmental Protection Agency
EPA East Building
1200 Pennsylvania Ave., NW
Mail Code: 4203M
Washington, DC 20460
Phone: (202) 564-0742
Fax: (202) 564-9539
Internet: http://www.epa.gov/npdes/sso
Publication Information
Office of Wastewater Management
833-R-02-001
March 2002
* 2002 *
THE YEAR OF
CLEAN WATER
SSO Case Study—Clearwater, Florida MOM Program
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