United States
                       Environmental Protection
                       Agency
 Office of Water
 Washington, D.C.
            EPA 832-F-00-069
            September 2000
 &EPA      Waste water
                       Technology  Fact  Sheet
                       In-Plant  Pump  Stations
DESCRIPTION

The terrain  of the treatment plant  site and the
influent sanitary sewer depth govern the need for
and location of in-plant pumping facilities. In-plant
pump stations are facilities that consist of pumps
and service  equipment designed to  pump flows
from lower to higher elevations to allow continuous
and cost-effective treatment through unit processes
within the plant.

The type of pumps most commonly used at
wastewater treatment plants include the centrifugal,
progressive cavity, and positive displacement.  The
three types are listed in Table 1 with the different
pump  applications.   Archimedes screw pumps
(progressive  cavity)  are  used to   pump  raw
wastewater and return activated sludge in treatment
plants, but only in larger facilities because of the
high purchase  cost.   These pumps are popular
because they are relatively easy to operate.

The focus of this section will be on centrifugal
pumps for raw wastewater and effluent pumping
applications.

Key elements of every pump station include: wet
well,  pumps, piping with  associated valves and
strainers, motors, power supply system, equipment
control and alarm system, odor control system and
ventilation system.  Pump  station  equipment and
systems are often installed in an enclosed structure.
Pump stations can be constructed on site (custom-
designed) or pre-fabricated in a factory.  Pump
station capacities range from 76 1pm (20 gpm) to
more than 378,500  1pm (100,000 gpm).  Pre-
fabricated pump stations generally have capacity of
up to 38,000 1pm (10,000 gpm). Usually, pump
      TABLE 1 PUMP APPLICATION
 Pump Type
Typical
Application
 Centrifugal
 Positive
 Displacement
 Progressive
 Cavity
Raw Wastewater

Primary Sludge

Secondary Sludge

Effluent Wastewater

Primary Sludge

Thickened Sludge

Digested Sludge

Slurries

Chemical Feed
Applications

All types of Sludge

All types of Slurries
Flush Water

Spray Water

Seal Water
 Source: WEF, 1992 and Sanks, 1992.

stations include at least two constant-speed pumps
ranging in size from 38 to 75,660 1pm (10 to
20,000 gpm) each and have a basic wet-well level
control system  to  sequence the pumps during
normal operation.

The most common method for pump control uses
liquid level controls that indicate when a desirable
water level is attained in the wet well.  A trapped
air column, or bubbler system that senses pressure
and level,  is commonly  used for pump station
control.  Other control alternatives are electrodes
placed at cut-off levels, and float switches. A more
sophisticated control operation involves the use of
variable speed drives.

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Buildings, although not necessary for the operation
of the  pumps, are required if service and repair
work have to be carried out  on-site, to protect
electrical equipment from weather, and to provide
room for personnel (sometimes in response to local
regulations).  Isolation valves are used to close off
the pumping station  or  parts  of it for routine
inspection  and maintenance  and repair of  the
structure. For large pump stations, the wet wells
are  divided  to  allow  for  future  repair   or
rehabilitation  while the pump  station continues to
operate.  Large sloping fillets or wet-well mixers
are used to minimize solids deposition in the wet
wells.   Designs for  self-cleaning wet wells  are
becoming more prominent.   Pump  stations  are
typically provided  with equipment  for  pump
removal. Floor doors or openings above the pump
room and an overhead monorail beam, bridge crane,
or portable hoist are commonly used.

Common Modifications

The two most commonly  used types of pump
stations are the dry-pit or dry-well and submersible
pump  stations.   In dry-well  pump  stations  the
pumps and valves are housed in a pump room (dry
pit or dry-well), that can be easily accessed.  The
wet well is a separate isolated chamber attached or
located adjacent  to  the  dry-well (pump  room)
structure.

The submersible  pump stations do not have a
separate pump  room,  however, the  pump station
header piping, associated valves, and flow meters
are located in  a separate dry vault on the surface for
easy access.  Submersible pump stations include
sealed  pumps that operate submerged in the wet
well. These submerged pumps are not intended for
frequent  inspection,   but  can be   removed
periodically to  the surface and re-installed using
guide rails and a hoist. Key advantages of the dry-
well pump stations are that they allow an easy
access   for  routine  visual  inspection   and
maintenance,  and in general they are easier to repair
than submersible pumps.  Key advantages of the
submersible pump station include lower costs than
the dry-well  stations and an  ability  to operate
without frequent pump maintenance.  In  addition,
submersible pump stations usually do not require
large  aboveground structures  and are easier  to
blend-in  with the  surrounding  environment  in
residential  areas.   They  require less space and
typically are easier and less expensive to construct
for wastewater flow capacities of  38,000  1pm
(10,000 gpm) or less. Figures 1 and 2 illustrate the
two types of pumps.
Source: Qasim, 1994.

        FIGURE 1 DRY-WELL PUMP
Based on the type of construction, two types of
pump stations are most common: custom-designed
and pre-fabricated (factory-built) pump stations.
Custom-designed stations are widely used for large
flow applications (22,700 1pm or 6,000 gpm and
above)  because  they   can  be  designed   to
accommodate practically any set of flows, heads,
footprint,  and   special  features.   In  addition,
                            Hoist
  Discharge
 Source: Qasim, 1994.
        FIGURE 2 WET-WELL PUMP

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custom-designed pump stations are typically more
spacious  and  accessible,  and  have  a  longer
structural life than factory-built pump stations.

Pre-fabricated  pump  stations  are available  in
various forms  and  can be  either  dry-well  or
submersible.   Pre-fabricated  pump  stations are
typically used for smaller flows because they are
more compact  and generally lower in cost than
custom-designed pump stations. Pre-fabricated dry-
well pump stations usually include steel or plastic
shell that is designed to house one to three vertical-
shaft flooded suction pumps.  Pumps, valves and
other equipment are installed at the factory prior to
shipment.  Circular station shells are more common
and larger pump stations can have an oval shape.
Pump station shells are typically bolted to cast-in-
place concrete base slabs at the job site.  In wet-
well configurations,  the  wet  well  usually  is
constructed of  pre-cast concrete.  Pre-fabricated
submersible stations  are typically  constructed of
pre-cast concrete or steel and can accommodate one
or two submersible pumps. For pre-cast concrete
stations, the  pump manufacturer may provide  a
complete   package   of   equipment,  including
submersible  pumps,  discharge  elbows,  check
valves, access hatches, and level controls.  For steel
stations, the equipment is typically pre-packaged at
the factory. Fiberglass tanks are typically used for
smaller pump stations.

APPLICABILITY

In-plant pump stations are used to move wastewater
from lower to higher elevation, particularly where
the elevation of the source is not sufficient for
gravity flow and/or the use of gravity conveyance
will result in excessive excavation depths and high
plant construction costs. In-plant pump stations are
used to pump flow from areas too low to drain by
gravity into nearby sewer lines.

Current Status

Variable speed pumping is often used to optimize
pump  performance  and  minimize  power  use.
Several types of variable-speed pumping equipment
are  available,  including  variable  voltage  and
frequency  drives,  eddy  current  couplings, and
mechanical variable-speed  drives.  Variable-speed
pumping can reduce the size and cost of the wet
well and allows the pumps to operate at maximum
efficiency under  a  variety  of flow  conditions.
Because variable-speed pumping allows pump
station discharge to  match inflow, only a nominal
wet-well storage volume is required and the well
water  level  is maintained  at a  near constant
elevation.  Variable-speed pumping may allow a
given flow range to be achieved with fewer pumps
than would a constant-speed alternative. Variable-
speed stations also minimize the number of pump
starts  and  stops,  reducing  mechanical  wear.
Although  there  is  a  significant energy  saving
potential for  stations with large friction losses, it
may not justify the additional capital costs unless
the cost of power is relatively high.  The variable
speed equipment also requires more room within
the pump station and may produce more noise and
heat than constant speed pumps.

Modern pump stations are equipped with automatic
controls   for  pump   starting  and   operational
sequencing.    The  pump stations typically have
standby pumps to increase reliability and provide
adequate capacity for unusually high flows.   In
unattended pumping stations, automatic controllers
are frequently used to allow switch over to standby
units when a pump fails. Flow recording equipment
is often installed to record instantaneous pumping
rates and the total flow pumped.

ADVANTAGES AND DISADVANTAGES

Limitations

Compared with gravity conveyance, pump stations
require an outside source of power.  If the power
supply  is  interrupted,   flow  conveyance  is
discontinued. Unless there are overflow structures,
discontinuation of pump station operation can result
in flooding the area upstream of the pump station
and can interrupt the  normal operations  of the
treatment facilities.   This  limitation is typically
handled by providing a stand by power source (e.g.,
back-up generator).

The useful  life of pump  station equipment is
typically limited to 20 to  30 years,  with good
maintenance.   Pump  station structures  typically
have a useful  life of 50 years.  The useful life of

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pump station  equipment  and structures can  be
prolonged by  using  corrosion-resistant  materials
and protective coatings.

Reliability

Pump stations  are complex facilities that contain a
significant  number  of equipment and  auxiliary
systems.   Therefore, they are less reliable than
gravity  wastewater  conveyance  but the  pump
station reliability can be significantly improved. A
way to improve the situation is by providing stand-
by equipment (pumps and controls) and emergency
power supply  systems. In addition, pump station
reliability is improved by  using screens to remove
debris, by using non-clog pumps  suitable  for the
particular  wastewater quality, and by  applying
emergency alarm and automatic  control systems.
Provisions are  often made for emergency overflow
or bypass of the pump station to protect  engine
driven pumps  and to provide more  reliable  and
uninterrupted operation.

Pump stations  have a relatively low impact on the
surrounding air and water and a moderate impact on
land  during   construction.     Key   potential
environmental  impacts of constructing  a  pump
station are noise, odor,   and emergency  sewer
overflows to nearby  surface waters. Pump  motor
operation  is  a  source  of noise, which  if  not
adequately mitigated, may negatively impact nearby
residential developments.  In an emergency (pump
malfunction, power failure, etc.)  a portion of the
wastewater conveyed to  the pump  station may
overflow to nearby surface waters causing potential
health  risk.   Emergency  sewer overflows  are
mitigated   by   installation  of   highly   reliable
equipment, providing redundant  control systems
and installing facilities for overflow storage and/or
treatment prior to discharge to surface waters.

Potential  odor  problems   are   mitigated   by
installation of various   odor control  systems,
including  reduction  of odor release by  adding
chemicals upstream  of  the pump  station  and
odorous gases evacuation and treatment at the pump
station site.  The addition of chemicals should be
closely   monitored  to   avoid  killing   any
microorganisms  downstream  (in the   extended
aeration process).
Advantages

Use of in-plant pump stations can reduce the depth
of plant structures.   For example,  consider  a
treatment   plant  located  on  uniform  ground
elevation.  Installation of an influent pump station
at the headworks of the facility could significantly
reduce the depth of downstream structures (such as
aeration basins, clarifiers,  and  contact  basins),
thereby reducing capital construction costs for the
entire facility.

Disadvantages

Key   disadvantages  of  in-plant  pump  stations
compared to gravity conveyance, are that they are
costly to operate and maintain, and are a potential
source of odors and noise.  In addition, pump
stations require a significant amount of power and
are prone to flooding during pump failure, which
may  spread over the adjacent structures.

Primarily due to the low cost of gravity conveyance
and the  higher costs of operating and maintaining
in-plant pump stations, the minimizing of in-plant
wastewater pumping should be a primary design
consideration.

DESIGN CRITERIA

Cost effective pump stations are designed to: (1)
match pump capacity, type and configuration with
wastewater  quantity; (2)  provide  reliable and
interruptible operation; (3) allow for easy operation
and maintenance  of  the  installed equipment; (4)
accommodate future capacity expansion; (5) avoid
septic conditions and excessive release of odors in
the collection system and at the pump station; and
(6) avoid  flooding of the  pump station  and the
surrounding areas.

Wet Well

Wet-well design is dependent on the type of pump
station configuration (submersible or dry-well) and
the type of pump controls  (constant or variable
speed).  Wet-wells are  typically  designed large
enough  to prevent rapid pump cycling, but small
enough  to prevent  a long detention time and
associated odor release.

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Wet-well  maximum  detention time  in  constant
speed pumps is typically 20 to 30 minutes. Use of
variable frequency drives for pump speed control
allows wet-well detention time reduction to 5 to 15
minutes.    Wet-well  bottom  slope  should  be
designed  to  allow self-cleaning  and  minimum
deposition of debris. Bar screens are often installed
in or upstream of the wet well to minimize pump
clogging  problems;  however,  screens  are  not
typically  required for  in-plant  stations because
course material is generally removed at headworks
in the plant.

Wastewater Pumps

The number of wastewater pumps and associated
capacity  should  be  selected to  provide head-
capacity characteristics (elevation of a free surface
of water) that correspond, as closely as possible, to
the wastewater quantity fluctuations.  This can be
accomplished by the preparation of pump/pipeline
system head-capacity curves showing all conditions
of head and capacity under which the pumps will be
required to operate.

The number of pumps to be installed in the pump
station depends largely on the station capacity and
range of flow.  In small stations, with maximum
flows of less than 2580 1pm (680 gpm), two pumps
are  customarily  installed, with each  unit having
capacity to meet the maximum influent rate.  For
larger pump stations, the size  and the  number
pumps should be selected so that the flow range can
be met without frequent starting and stopping of
pumps and without requiring excessive wet-well
storage.

The pumps  are designed to run alternately  in an
effort to  keep  wear and tear even, as well  as
keeping all of the parts are lubricated.  Additional
pumps may be  needed to provide intermediate
capacities that are better matched to typical daily
flows. Another option is to provide flow flexibility
with variable-speed pumps.   Usually, the single
pump peak  flow approach is most  suitable  for
stations that have relatively rapid flow increase or
high  headlosses.   For  such stations,  parallel
pumping is  not as effective, because two pumps
operating  together yield only slightly higher flows
than one pump. If the peak flow is to be achieved
with multiple pumps in parallel, the pump station
will need to be equipped with at least three pumps:
two duty pumps that together provide peak flow and
one standby pump for emergency backup.  Parallel
peak pumping is typically used for large pump
stations with relatively flat system head  curves.
Such operation allow multiple pumps to deliver
substantially more  flow than  a  single pump.  In
addition, use of multiple pumps in parallel provides
more flexibility.

Several types of centrifugal pumps are frequently
used at in-plant  pump  stations.  In straight-flow
centrifugal pumps the wastewater does not change
direction of  flow as it passes through the pumps
and into the  discharge pipe.   These pumps  are
suitable for  low-flow/high head conditions.  In
angle-flow  pumps, the  wastewater enters  the
impeller  axially  and passes  through  the  volute
casing at 90 degrees to its original direction (Figure
3).  This type of pump is  appropriate for pumping
against low or moderate  heads. Most viable for
pumping large quantities of wastewater at low head
are the mixed flow pumps.  In these pumps,  the
outside diameter of the impeller is less than that of
an ordinary centrifugal pump, hence the flow speed
is greater.

Ventilation

Ventilation and  heating  are  required if  the  lift
station  includes  an  area  of  the  facility  that is
routinely entered by personnel.   Ventilation is
particularly important to prevent the collection of
toxic and/or explosive gases in the pump  station.
According  to   the  National  Fire  Protection
Association (NFPA) 820, all continuous ventilation
systems should be fitted with flow detection devices
connected to alarm signaling systems to indication
ventilation system  failure.  Dry-well ventilation
codes typically require 6 continuous air changes per
hour or 30 intermittent air changes per hour. Wet
wells typically require 12 continuous air changes
per hour or 60 intermittent air changes per hour.
Motor control center (MCC) rooms should have a
ventilation  system  adequate  to  provide  6  air
changes per hour and should be air conditioned to
13 to 32 degrees C (55 to 90 degrees F). If the
control room  is combined with an MCC room, the
temperature should not exceed 30 degrees  C or 85

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                               t
               Impeller
                                   Discharge line
                     \U-I
           Suction line      V
                                 Casing
Source: Lindeburg, revised edition 1995.

 FIGURE 3 CENTRIFUGAL ANGLE-FLOW
                    PUMP

degrees F. All other spaces should be designed for
12 air changes per hour.  Minimum temperature
should be 13  degrees C  (55 degrees F) whenever
chemicals are stored or used.

Odor Control

Odor control  is  frequently required  for pump
stations.  A relatively simple and widely used odor
control alternative includes minimizing wet-well
turbulence.    More   effective  options   include
collection of odors generated at the pump station
and their treatment in scrubbers or biofilters, or the
addition of odor control chemicals to the sewer
upstream of the pump station.  Chemicals typically
used for  odor control include chlorine, hydrogen
peroxide, metal salts (ferrous chloride and ferric
sulfate); oxygen, air and potassium permanganate.

Power Supply

The reliability of power for the pump motor drives
is a basic design consideration.  Commonly used
methods  for  emergency power  supply  include
electric power feed from two independent power
distribution lines; an on-site standby generator; an
adequate portable generator with quick connection;
a stand-by engine driven pump; ready access to a
suitable portable  pumping unit and appropriate
connections; and availability of an adequate holding
facility for wastewater storage upstream of the
pump station.

PERFORMANCE

The  overall performance  of the pump stations
depends on the performance of their pumps.  All
pumps   have   four  common  performance
characteristics: capacity, head, power and overall
efficiency.  Capacity (flow rate) is the quantity of
liquid pumped per unit of time, typically measured
as gallons per minute (gpm) or million gallons per
day (mgd).  Head is the energy supplied to the
wastewater per unit weight, typically expressed as
feet of water. Power is the energy consumed by a
pump per unit time, typically measured as kilowatt-
hours.  Overall  efficiency  is the ratio of useful
hydraulic work performed to the actual work input.
Efficiency reflects the pump relative power losses
and is usually measured as a percentage of the
applied power.

Pump performance curves (Figure 4) are used to
define and compare the operating characteristics of
a given pump and to identify the best combination
of performance  characteristics under  which the
pump station pumping  system will operate under
typical conditions.  Well designed pump systems
operate at 75 to 85 percent  efficiency most of the
time.   The  overall  pump  efficiency  is highly
dependent on the type of the installed pumps, their
control system and the fluctuation of the influent
wastewater  flow.    Performance  optimization



I40"
i
I 30 -







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"^\ ^/
'_ 	 __^—^ \

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0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4
Discharge (m3/s)
Source: Adapted from Roberson and Crowe, 1993.

 FIGURE 4 PUMP PERFORMANCE CURVE

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strategies  focus  on  matching pump  operational
characteristics  with  system  flow  and  head
requirements.   They may  include the following
options: adjusting system  flow  paths; installing
variable  speed  drives;  using   parallel  pumps;
installing  pumps  of different  sizes; trimming  a
pump impeller; putting a gear reducer and a two-
speed motor on one or more pumps in the pump
station.  While savings will vary with  the system,
electrical energy savings in the range of 20 to 50
percent   are   possible  by  optimizing   system
performance.

OPERATION AND MAINTENANCE

Pump station operation  is usually automated  and
does  not  require  continuous   on-site  operator
presence.   However,  frequent  inspections  are
recommended to assure normal functioning of
pump station equipment and to identify potential
problems early.  Weekly pump  station inspection
typically includes observation of pumps,  motors
and drives for unusual noise, vibration, heating or
leakage; check of pump suction and discharge lines
for valving  arrangement and leakage; check of
control  panel   switches  for  proper  position;
monitoring of discharge pump  rates  and  pump
speed; and  monitoring  of pump  suction  and
discharge  pressure.  If a pump station is equipped
with bar screens to  remove coarse materials from
the  wastewater,  these  materials  are collected
automatically  or  manually  in   containers  and
disposed to a sanitary landfill site once a week or as
needed.  If the pump station has a scrubber system
for odor control, chemicals for this  system  are
supplied and replenished typically once every  one
to three months.  If chemicals are added for odor
control ahead of the pump  station,  the  chemical
feed  stations  should be  inspected weekly  and
chemical supplies replenished as needed.

The most labor-intensive task for pump stations is
routine preventive maintenance.   A well-planned
maintenance  program  for  pump station  pumps
prevents   unnecessary   equipment   wear   and
downtime.   Regardless  of the excellence  of
servicing programs,  equipment use causes wear
and, ultimately, failure or breakage of parts.  Pump
station operators must have an inventory of critical
spare parts available. The number of spare parts in
the inventory depends on the critical needs of the
unit, the rate at which the part would normally fail,
and the availability of the part. The operator of the
pump station  needs to tabulate each  pumping
element in the system and its recommended spare
parts. This information is  typically available from
the  manufacturer's  operation  and maintenance
manuals provided with the pump station.

COSTS

In-plant pump station costs depend on many factors
including: (1) flow and quantity of the liquid being
pumped,   (namely,  wastewater,  sludge   or
chemicals); (2) depth of the required structures; (3)
alternatives  for  standby  power sources;   (4)
operation and maintenance needs and support; (5)
soil properties and underground conditions; (6) the
severity of impact of accidental  sewage spill upon
the local  area; and (7) the need for an odor control
system.  These site and system specific factors must
be examined and incorporated in the preparation of
pump station cost estimate.

Construction Costs

The most important factors influencing costs are the
design pump  station capacity  and the installed
pump power. Another important cost factor is the
pump station complexity.   Factors which would
classify a pump station as complex include two or
more of the  following  items:  (1)  subsurface
condition;  (2)  congested  site  and/or restricted
access;   (3)  rock   excavation;  (4)  extensive
dewatering requirements such as cofferdams; (5)
site conflicts, including modification or removal of
existing facilities;  (6) special foundations including
piling; (7) dual power supply and on-site switch
stations and emergency power generator; (8) high
pumping heads.

Typically in-plant pump stations  are less expensive
than their collection system (lift station) counter
parts. Pump station construction has a significant
economy-of-scale. Typically, if the capacity of a
pump  station  is increased 100  percent,   the
construction cost  would  only increase about 50 to
55 percent. An important practical consideration is
that two identical  pump stations  would  cost
approximately 25  to 30 percent more than a single

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station of the same combined capacity.  Usually,
complex  pump  stations  cost two to three times
more than  more simple pump stations with no
construction complications.

Construction costs for in-plant pump stations are
usually not segregated, but rather included in the
overall capital construction  costs for a treatment
facility.  Therefore, there is  a wide range of costs
starting as low as $30,000 and reaching as high as
$1,000,000 (Pasco, 2000). The low end cost is for
small plants  while  the  higher  end  includes
sophisticated equipment and/or a large plant.

Operation  and  Maintenance Costs

Pump station operation and maintenance (O&M)
costs include  costs  for  power,  labor  and
maintenance. If chemicals are used at  the pump
station for odor  control, O&M costs will include
the cost for  chemicals.  Usually, the costs for solids
disposal are minimal, but are considered a part of
the O&M costs if the pump station is equipped with
bar screens to remove coarse materials from the
wastewater. Typically, power costs are 85 to 95
percent of the total O&M costs and are directly
proportional to the unit cost of power and the actual
power used by  the pump station pumps.  Labor
costs are usually 1 to 2 percent of total O&M costs.
Annual maintenance costs vary, depending on the
complexity  of the equipment and instrumentation.

REFERENCES

Other Related Fact Sheets

Sewers, Lift Stations
EPA 832-F-00-073
September,  2000

Other EPA Fact Sheets can be found  at  the
following web address:
http://www.epa.gov/owmitnet/mtbfact.htm

1.     Cavalieri R.R. and G. L. Devin  Pitfalls in
       Wet Weather Pumped Facilities Design. In
      Proceedings  of the Water  Environment
      Federation,   71st  Annual  Conference,
      Orlando, Florida, Vol. 2, 719-729, October
       1998.
10.
11.
Don  Casada.    Pump Optimization for
Changing Needs. Operations Forum. Vol. 9,
No. 5, 14-18, May 1998.

Environmental Protection Agency.  Design
Manual.  Odor and Corrosion Control in
Sanitary Sewerage Systems and Treatment
Plants.  EPA/625/1-85/018, October  1985.

Gravette B.  R.   Benefits  of  Dry-pit
Submersible Pump Stations. In Proceedings
of the Water Environment Federation, 68th
Annual Conference, Miami Beach,  Florida,
Vol. 3, 187-196, October 1995.

Graham B,  I, Pinto T.G. and T. Southard.
Backyard Pumping Stations - The  Low-
pressure Grinder Systems That Call Old
Septic Tanks Home. Operations Forum, Vol.
10, No. 5, 25-29, May 1993.

Jackson J.  K.    Variable  Speed Pumping
Brings  Efficiency  to  Pump  Systems.
Operations  Forum,Vol. 13, No. 5, 21-24,
May 1996.

Lindeburg,  Michael R.  Civil Engineering
Reference Manual, 6th ed., Professional
Publications, Inc., revised edition 1995.

Makovics   J.    S.   and   M.   Larkin.
Rehabilitating Existing Pumping Systems:
Trips,  Traps  and Solutions.  Operations
Forum, Vol. 9, No. 5, 10-17, May  1992.

Metcalf  &  Eddy   Inc.,   Wastewater
Engineering: Collection and Pumping of
Wastewater, McGraw Hill Book Company,
1981.

National  Fire  Protection  Association.
National Fire  Codes.  Volume 7,  Section
820.  Quincy, Massachusetts, 1995.

Paschke  N.W.   Pump Station Basics -
Design Considerations for a Reliable Pump
Station. Operations Forum, Vol. 14, No. 5,
15-20, May 1997.

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12.
13.
14.
15.
16.
17.
18.
19.
20.
Public Works Journal.  The 1997 Public
Works Manual. April 15, 1997.

Qasim,  Syed R.  Wastewater Treatment
Plants - Planning Design,  and Operation.
Technomic Publishing company, Inc., 1994.
Rotondo/Carlgen,   2000.
personal   communication
Engineering Science, Inc.
 Ken  Pasco,
with  Parsons
Russell    Edward.       Screw-Pump
Preservation. Operations Forum, Vol.  9,
No. 5, 18-19, May 1992.

SanksR. L., TchobanoglousG., Newton D.,
Bosserman, B.E., Jones, G. M.  Pumping
Station Design, Butterworths, Boston, 1989.

Schneller T. M. Pumping it Up? Practical
Means For Evaluating Lift Station Fitness.
In Proceedings of the Water Environment
Federation, 68th Annual Conference, Miami
Beach, Florida, Vol.  3, 155-166 October
1995.

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Efficiency Game. Operations Forum, Vol.
11, No. 7,  18-21, July 1994.

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Largest. Dry-Pit/Submerged Pumps Make
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ADDITIONAL INFORMATION

Miami-Bade Water and Sewer Department
Luis Aguiar, Assistant-Director
4200 Salzedo Street
Coral Gables, FL 33146

East Bay Municipal Utility District
Eileen M. White
P.O. Box 24055
Oakland, CA 94523

Wastewater Treatment Plant
Richard R. Roll
P.O. Box 69
Niagara Falls, NY 14302

City of Houston DPW and Engineering
Gary N. Oradat
Utility Maintenance Division
306 McGowen Street, Houston, TX 7706

City of Fayetteville
David Jurgens
113 West Mountain Street
Fayetteville, AR 72701

Water & Wastewater Utility
Bruno Conegliano
City of Austin, P.O. Box 1088
Austin, TX 78767

The  mention  of trade  names  or  commercial
products does  not  constitute  endorsement  or
recommendations  for use  by the United  States
Environmental Protection Agency (EPA).
                                                         For more information contact:

                                                         Municipal Technology Branch
                                                         U.S. EPA
                                                         Mail Code 4204
                                                         1200 Pennsylvania Avenue, NW
                                                         Washington, D.C. 20460
                                                          »MTB
                                                         Excelence fh tompfance through optfhial tethnltal solutfons
                                                         MUNICIPAL TECHNOLOGY BRANCH

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