El Centro City Council
January 20, 2026

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 6 OCTOBER 2025
Condition Description
Fair
Observed to be in satisfactory operating condition while containing minor corrosion, rust, painting deterioration, or structural deficiencies. Normal wear and maintenance of the facility or components is observed and more frequent inspection and monitoring by City Staff may be warranted. City staff may have reported significant operations or maintenance deficiencies related to the equipment, structure, or gear.

Poor
Observed to be functioning below acceptable operating conditions and/or exhibiting high levels of corrosion, rust, painting deterioration, or structural deficiencies. More frequent monitoring and maintenance is required. City staff have reported significant operations or maintenance deficiencies and concerns.

It is recommended that the City maintain its normal schedule for operation and maintenance, as well as frequency of monitoring the condition of the facility equipment, structures, or gear, with an “Excellent” or “Good” overall facility condition. More frequent monitoring and/or maintenance as well as potential rehabilitation or replacement may be warranted for equipment, structures, or gear for stations that were assessed to be in overall “Fair” condition. It is recommended that the City rehabilitate or replace equipment, structures, or gear for facilities with an overall “Poor” assessed condition immediately and perform more frequent maintenance and monitoring of the condition until rehabilitation or replacement.

Examples of observed asset conditions (i.e., excellent, good, fair, poor) for mechanical, structural, electrical, and site/civil elements are displayed on Table 3. These examples were provided to standardize evaluations and offer a clear understanding of what each condition designation represents, aligning with the goal of creating actionable and transparent assessments and recommendations.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 7 OCTOBER 2025
Table 3. Condition Assessment Designation Examples
Condition
Mechanical (Pumps, Piping, Valves,
and Appurtenances)
Description
Excellent
• Observed to be new or like new
• No corrosion, rust, coating deterioration or structural deficiencies observed
• No reports of operations and maintenance
deficiencies or concerns such as excessive noise,
vibration, or leaks
• No need for replacement in the foreseeable future
• No potential risk of Sanitary Sewer Overflow (SSO)
Good
• Observed to be operating as intended
• Minimal corrosion, rust, coating deterioration, and no structural deficiencies observed
• Normal wear and maintenance of the asset observed
but does not appear to be inhibiting performance
• No reports of significant operations and maintenance
deficiencies or concerns
• Minimal to no potential risk of SSO
• End of useful life 10 to 20 years away

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 8 OCTOBER 2025
Condition Mechanical (Pumps, Piping, Valves, and
Appurtenances)
Description
Fair
• Observed to be in satisfactory operating condition
• Minor to moderate corrosion, rust, coating
deterioration, and insignificant structural
deficiencies observed
• Normal wear and maintenance of the asset observed
and may require more frequent inspection and
monitoring
• Reports of moderate operations and maintenance
deficiencies or concerns, minimal frequency
• Minor to moderate potential risk of SSO, minimal
frequency
• End of useful life approaching: 4 to 10 years away

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 9 OCTOBER 2025
Condition
Mechanical (Pumps, Piping, Valves, and
Appurtenances)
Description
Poor
• Observed to be functioning below acceptable
operating conditions
• Exhibiting moderate to severe corrosion, rust, coating deterioration, and significant structural deficiencies
observed
• At or near the end of its useful service life;
maintenance of the asset may require more frequent
inspection and monitoring
• Reports of operations and maintenance deficiencies
or concerns at a moderate to high frequency, such as
excessive/unusual noise, excessive heat output,
vibration, leaks, ragging
• Exhibiting signs of failure or potential imminent
failure
• Severe risk of SSO
• Very near the end of useful life, should be replaced in the near future: 1 to 3 years
• Needs replacement right away, currently does not
operate/function properly

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 10 OCTOBER 2025
Condition Metals Description
Excellent
• Little to no corrosion
• No general loss of wall thickness
• Minimal to no wall thickness loss from pitting
• Widespread but insignificant extent of corrosion
Good
• Minor corrosion
• Minimal general loss of wall thickness
• Minimal wall thickness loss from pitting
• Localized extent of corrosion
Fair
• Moderate corrosion
• Moderate general loss of wall thickness
• Moderate wall thickness loss from pitting
• Extent of corrosion observed on up to half of the
surface
Poor
• Severe corrosion
• Signs of failure or potential imminent failure
• Significant general loss of wall thickness
• Significant wall thickness loss from pitting. Pinholes and holes observed on the surface
• Extent of corrosion observed on up to half of the
surface

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 11 OCTOBER 2025
Condition Concrete Description
Excellent
• Minimal to no damage to concrete
• Hard surface
• Smooth, apparently intact surface profile
• Hairline width cracks, minimal frequency
• No spalling
• Reinforcement not exposed or damaged
Good
• Minor concrete surface damage
• Soft surface to 1/8-inch depth
• Fine aggregate exposed
• Hairline width cracks, moderate frequency
• Shallow spalling, minimal frequency
• Reinforcement not exposed or damaged
Fair
• Moderate concrete surface damage
• Soft surface to 1/4-inch depth
• Large aggregate exposed or protruding
• Up to 1/32-inch width, moderate frequency
• Shallow spalling, minimal frequency
• Reinforcement exposed; minor damage, minimal
frequency
Poor
• Loss of concrete mortar and damage to
reinforcement
• Bulk loss of concrete and reinforcement
• Soft paste beyond 1/4-inch depth
• Large aggregate exposed, loose, or missing
• 1/8-inch width or greater, moderate to high
frequency
• Deep spalling, moderate to high frequency
• Reinforcement exposed with damage, moderate
frequency; or reinforcement consumed causing a
loss of structural integrity

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 12 OCTOBER 2025
Condition Site Civil/Safety & Security Description
Excellent
• Observed to be new or like new
• Low to no threat of injury
• Negligible risk
• Insignificant consequence
• No regulatory violations/fines
• No reports of significant operations and maintenance
deficiencies or concerns
• No need for replacement in the foreseeable future
• Good security measures to prevent unauthorized
access
• Sufficient site lighting
Good
• Observed to be operating as intended
• Minor threat of injury
• Minor risk
• Minor consequence
• No reports of significant operations and maintenance
deficiencies or concerns
• Normal wear and maintenance of the asset observed
but does not appear to be inhibiting performance
• No regulatory violations/fines
• End of useful life 10 to 20 years away
• Good security measures to prevent unauthorized
access
• Adequate site lighting

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 13 OCTOBER 2025
Condition Site Civil/Safety & Security Description
Fair
• May require medical attention in the event of an
injury
• Moderate risk and economic consequence could
result
• Normal wear and maintenance of the asset
observed; may require more frequent inspection and
monitoring
• Reports of moderate operations and maintenance
deficiencies or concerns, minimal frequency
• Possibility of regulatory violations/fines
• End of useful life approaching: 4 to 10 years away
• Lacks sufficient security measures against
unauthorized access
• Insufficient site lighting
Poor
• High risk; hospitalization or possibly death from
serious injuries could result
• Active major regulatory violations/fines
• Potential of catastrophic failure that requires
immediate attention
• Major consequences
• Widespread public interest and potential public
investigation
• At or near the end of its useful service life should be replaced in the near future: < 3 years
• Maintenance of the asset may require more frequent
inspection and monitoring
• Nonfunctional or no security measures in place to
prevent unauthorized access
• Nonfunctional or no existing site lighting

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 14 OCTOBER 2025
Condition
Electrical (Telemetry, Panels,
Instrumentation, Meters, Lighting,
Conduits and Conductors, Sensors)
Description
Excellent
• Observed to be new or like new
• No corrosion, rust, coating deterioration or structural deficiencies observed
• No reports of operations and maintenance
deficiencies or concerns such as excessive heat
output and excessive noise
• No need for replacement in the foreseeable future
• No code violations
Good
• Good condition, observed to be operating as
intended
• Minimal corrosion, rust, coating deterioration, and no structural deficiencies observed
• Normal wear and maintenance of the asset observed
but does not appear to be inhibiting performance
• No reports of significant operations and maintenance
deficiencies or concerns
• No code violations
• End of useful life 10 to 20 years away
Fair
• Fair condition, observed to be in satisfactory
operating
• Minor to moderate corrosion, rust, coating
deterioration, and insignificant structural
deficiencies observed
• Normal wear and maintenance of the asset observed
and may require more frequent inspection and
monitoring
• Reports of moderate operations and maintenance
deficiencies or concerns, minimal frequency
• New arc flash study and labels needed in the near
future: 1 to 3 years
• Minor code violations, minimal threat of injury
• End of useful life approaching: 4 to 10 years away

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 15 OCTOBER 2025
Condition
Electrical (Telemetry, Panels,
Instrumentation, Meters, Lighting,
Conduits and Conductors, Sensors)
Description
Poor
• Observed to be functioning below acceptable
operating conditions
• Exhibiting moderate to severe corrosion, rust, coating deterioration, and significant structural deficiencies
observed
• At or near the end of its useful service life should be replaced in the near future: < 3 years
• Maintenance of the asset may require more frequent
inspection and monitoring
• Reports of operations and maintenance deficiencies
or concerns at a moderate to high frequency, such as
excessive/unusual heat output and excessive noise
• Exhibiting signs of failure or potential imminent
failure
• Arc flash study and labels are missing or outdated
• Major code violations, moderate to severe threat of
injury

2.4 Summary of Condition Assessment Results
A condition assessment designation for each asset discipline was indicated for all of the City’s sewer lift stations, which accounts for the overall representative average asset condition per discipline at all of the lift stations. A general summary of the average asset condition within each discipline can be seen in Table 4. These representative asset conditions were based on the results of the condition assessment for the City’s sewer lift stations which take into consideration asset condition, relative criticality and safety risk, increased risk of SSO, and asset useful life.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 16 OCTOBER 2025
Table 4. General Evaluation Summary for Lift Stations by Asset Discipline Lift Station Site Civil Mechanical Structural
Electrical &
Instrumentation
Climate
Vulnerability
Lift Station
No. 3 Excellent Fair to Good Poor Poor to Fair Poor
Gios Excellent Fair to Good Poor Poor to Fair Poor
Main Excellent Fair to Good Fair Poor Good
Countryside Excellent Fair Poor to Fair Poor to Fair Fair to Good Legacy Excellent Fair Good Good Good
Alder Canal
/ Villa Ave Excellent Fair Fair Fair Good to Fair
3rd & Ross Excellent Fair Poor Fair Poor
4th & Wake Good to
Excellent Good Poor Fair Fair
8th & Wake N/A1 Fair Poor N/A1 N/A1
Lift Station
No. 2 N/A1 Fair to Good Excellent N/A1 N/A1
Orange Ave N/A1 Good Poor N/A1 N/A1
Lift Station
No. 1 Excellent Fair to Good Fair to Good Good Poor
Buena Vista N/A1 Good Fair to Good N/A1 N/A1
East Side N/A1 Fair Good N/A1 N/A1
Heil &
Dogwood N/A1 Poor to Fair Fair to Good N/A1 N/A1

1. An evaluation was not performed for this asset discipline as discussed in Section 1.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 17 OCTOBER 2025
3 Lift Station Assessments
This section describes the following information for each of the evaluated lift stations:
• Location and Layout
• System Characteristics
• Inspection Summary
• Hydraulic Assessment
• Recommended Improvements
Notably, recommended improvements were categorized into two classes: (1) maintenance actions and (2) capital actions. Maintenance actions are defined as low-cost solutions that could be completed the City’s operation and maintenance staff. Capital actions consist of asset or equipment rehabilitation, replacement, or demolition, that require the hire of an outside contractor and/or consultant to complete the work and therefore are need to be included in the Lift Station CIP.

3.1 Lift Station No. 3

3.1.1 Location and Layout
The City of El Centro’s Lift Station No. 3 is located at 2255 N La Brucherie Road, within the El Centro Wastewater Treatment Plant (WWTP) property. The site can be accessed by the gated WWTP main entry way drive on North La Brucherie Road. There is sufficient parking adjacent to the lift station. Lift Station No. 3 is a dry well / wet well lift station that regulates flow entering the WWTP.

Figure 2: Lift Station No. 3 Location

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 18 OCTOBER 2025
Figure 3: Lift Station No. 3 Layout

3.1.2 System Characteristics

3.1.2.1 Pump Station
A summary of the pumping units for Lift Station No. 3 is provided on Table 5, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and the force main are summarized on Table 6.

Table 5. Lift Station No. 3 Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Chicago Pump LS8-4A
Pump Type Dry well
Mount Pedestal Mount
Design Capacity 3,000 gpm @ 37’ TDH (City provided)
Motor, hp 40
Motor Operation (2) Pumps Soft Starts; (1) Pump VFD
Speed, rpm 880
Discharge Diameter, inches 8
Year Installed 2006

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 19 OCTOBER 2025
Table 6. Lift Station No. 3 Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Lined concrete
Diameter, feet 32’ x 10’
Depth, feet 31.3’
Floor Elevation, feet -76.75’
Influent Sewer Invert, feet -72.33’
Cover/Hatch Type Single-leaf hatch
Bypass Assembly
Valve Location Dry well
Bypass Connection None
Force Main
Diameter 24”
Length Approximately 400’ (obtained from GIS)
Material Ductile Iron

3.1.2.2 Operations and Maintenance History
Operations reported that the pumps at Lift Station No. 3 are overhauled every five years. During one scheduled refurbishment, the impellers were trimmed to reduce flow and better match system demand. Originally, all three dry pit pumps used VFDs. However, at low speeds, the pumps could not maintain enough pressure to move flow through the force main. To address this, Operations replaced two of the VFDs with soft starters and now run those pumps at full speed. The third VFD is planned to be replaced with a soft starter when it fails.

The bar screen system was installed in 2018, which according to City staff improved ragging issues previously experienced at this site. Due to high flows in summer, the bar screen confined space vault can only be accessed during winter. Operations also noted that the wet well is rarely cleaned due to limited access, poor visibility, and its depth. Operations staff informed that this wet well rarely has to be bypassed.

The PLC requires frequent maintenance. When it fails, the City receives either a pump failure or high-level alarm.

The SCADA system only receives alarms from the PLC and does not collect flow data.

3.1.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at Lift Station No. 3. Table 7 contains observations made during the February 11, 2025 site inspection and information provided by the City during the pre- and post-inspection workshops.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 20 OCTOBER 2025
Table 7. Lift Station No. 3 Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ Surrounding site grading fair. Unpaved and
becomes muddy during precipitation events
▪ Low points in dirt around perimeter of the lift
station slab causing ponding
- Ponding water at low points and/or high
groundwater may be causing infiltration
at dry well structure joints; Infiltration
water marks observed at joints on the
interior of the dry well
▪ The lift station site is within the WWTP
perimeter security fencing
▪ Wet well access hatch was observed to be
experiencing moderate corrosion in localized
areas. No permanent/integrated fall
protection observed at wet well access
hatch. Portable 3 sided safety railing was
positioned around wet well access hatch at
time of inspection. Lift assist was not
observed to be functioning
▪ Outdoor lighting recently installed at the lift
station
▪ It was observed that the bar screen motor
can only be accessed by a standard ladder
(unfixed). No safety railings at the top of the
bar screen
▪ No working intrusion switches or locks on
the dry well or wet well access hatches.
- Only working intrusion switch observed
onsite is located at bar screens vault
entry door
▪ Mobile safety railing around wet well hatch
has moderate corrosion and coating
delamination
Good
Figure 4: Lift Station No. 3 Site Grading and Access
Figure 5: Lift Station No. 3 Site Safety

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 21 OCTOBER 2025
Mechanical Condition Photo(s)
Pumps
▪ Three (3) dry pit pumps within dry well. Dry
well contains pedestal and piping stub outs
for two (2) future pumps
▪ Varying levels of corrosion and coating
delamination observed to be occurring on
pumping units. Severe corrosion was
observed at Pump 3 base. Structural
integrity of pump base anchor bolts may be
at risk of failure in the near term. Seal leak
at Pump 3 is believed to be causing
accelerated corrosion
- Pump 1 and 2 volutes and motors
appear to be in good condition with
normal signs of wear and tear on coating
▪ Pumps located on concrete pedestals.

Pedestals in good condition
▪ Pumps are controlled with level transducers
with high water alarm floats.
▪ Operations have to use truck crane to
remove pumps from dry well. No permanent
bridge crane within dry well. Existing gantry
crane observed onsite adjacent to dry well
pump access hatches.
- It is standard for dry wells of this size and
design to have a monorail within the dry
well for pump removal and maintenance,
and a crane at grade can then remove
pumps or equipment at a single location.

Bar Screens
▪ Minor surface corrosion observed at
localized areas on bar screen equipment.
- Observed grease and debris buildup on
exterior of bar screen equipment caused
from leakage at multiple locations.

Overall condition of bar screen is fair
▪ Operations staff reported high summer flows
limit bar screen vault access due to
surcharging of the channel within bar screen
vault. Dudek was not able to access the
vault at the time of the inspection
▪ High H2S levels observed in the bar screen
vault.

Poor/Fair
Figure 6: Lift Station No. 3 Dry Well Pumps
and Pump Base
Figure 7: Lift Station No. 3 Bar Screen (Side View)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 22 OCTOBER 2025
Piping and Valves
▪ Most assets appear to be in fair to good
condition
- Varying levels of minor corrosion and
coating delamination are occurring,
particularly at flanges
- Rate of corrosion may be accelerated by
exposure to H2S in wet well vapors
▪ Piping and valves appear to have an
overcoat
▪ No flow meter present at lift station
▪ No force main bypass connection observed
at this lift station
Good /
Excellent
Figure 8: Lift Station No. 3 Piping and Valves
Odor Control/Ventilation
▪ Moderate corrosion observed on ventilation
inlet blower. Minor surface corrosion
observed on ventilation exhaust blower.
▪ Temporary ventilation was observed at the
bar screen confined space vault.
▪ Ventilation ducts within the dry well are in
excellent condition.

Fair
Figure 9: Lift Station No. 3 Forced Air Ventilation
Structural Condition Photo(s)
Dry Well
▪ Sections of the dry well concrete were
observed to be flaking
▪ Minor spalling observed at the bottom stair.

Moderate crack located after on dry well
floor at base of stairs
▪ Infiltration located at dry well joints
▪ Dry well sump pump system has failed twice
in the past. City was not notified of dry well
flooding due to failure of the flood float
switch (located near pump 1)
- Sump pump controlled by level floats
▪ Gas sensor in the dry well was not
functioning at the time of the inspection.
- Operations informed that the H2S alarm
was disconnected after it repeatedly
failed
▪ Forced air ventilation system is in good
condition
Poor/Fair
Figure 10: Lift Station No. 3 Dry well structure
Figure 11: Lift Station No. 3 H2S Sensor

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 23 OCTOBER 2025
Wet Well
▪ Portions of the wet well liner under the dry
well access stair are observed to be
separating from the structure
▪ Walkway within the wet well has filled with
debris. Dudek was unable to inspect the
walkway or the wet well beneath the
walkway as a result
▪ Liner is delaminating and concrete is
experiencing moderate to severe corrosion
around the wet well access opening
▪ Poor lighting observed within the wet well.
▪ Operations informed that the wet well level
has never got high enough to surcharge
influent pipe.

Figure 12: Lift Station No. 3 Wet Well Liner Delamination Figure 13: Lift Station No. 3 Wet Well Raised Walkway
Panel Enclosure Building
▪ Panel enclosure building was observed to be
in good condition.
▪ Minor cracking at panel enclosure building
access stair
▪ Moderate corrosion at forced air ventilation
ducting
- Corrosion primarily at ducting joints
Good
Electrical & Instrumentation Condition Photo(s)
Electrical Building
▪ The exterior of the MCC in the Electrical
Building appeared to be in good condition
and have 15 years of useful life remaining.
▪ City staff reported that they have replaced
two of the three VFDs in the MCC with soft
starters when the VFDs failed, and will
replace the third VFD with a soft starter
when it fails.
▪ Corrosion from H2S gas reported by staff in
the MCC and other electrical equipment.

Staff reported having to remove corrosion
from the MCC bus bars.
▪ No sealing fittings were observed on any
conduits on site and are required per the
National Electrical Code and California
Good
Figure 15: Lift Station No. 3 Electrical Building
Interior & MCC
Figure 14: Lift Station No. 3 Panel
Enclosure Building

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 24 OCTOBER 2025
Electrical Code on conduits once they leave
a hazardous area, such as the wet well. A
lack of sealing fittings is a safety hazard, a
risk for equipment damage, and is likely the
reason for H2S gas entering the Electrical
Building.
▪ Lighting appeared sufficient inside the
building and in good condition. Staff
indicated that the fluorescent bulbs were
replaced by installing LED light tubes inside
the existing fluorescent light fixtures.
▪ Exterior lights all appeared to have been
replaced with LED fixtures except one.

Newer lights are in good condition.
▪ No arc flash stickers were observed in the
electrical building, or anywhere on site.
▪ No third-party maintenance/testing stickers
were observed on the electrical equipment.
▪ City staff indicated that the pumps start and
stop based on contacts from the ultrasonic
level transmitter, and that there is no
backup pump control using float switches.
▪ The existing site PLC is an Allen-Bradley
Micrologix 1500, which was discontinued in
2017 according to the manufacturer’s web
site. New parts are no longer available.
▪ I/O is transmitted off site using a Mission
Communications Cellular Wireless RTU, for
the lift station and the bar screen.

Outdoors
▪ City staff advised that the intrusion switches
on the dry well and wet well access hatches
do not work. Staff would like all intrusion
switches to work.
- The only working intrusion switch
observed onsite is located at bar screens
vault entry door.
▪ Sealing fittings were not observed on
conduits that exit the wet well and continue
outside of the hazardous area, such as the
ultrasonic sensor conduit, and the float
switch conduit.
▪ According to City staff, power is provided to
Lift Station #3 from the WWTP, and the
power feed is backed up by a standby
generator at the WWTP.
▪ No lift station discharge flowmeter was
observed.

Fair
Figure 16: Lift Station No. 3 Level Sensor Mounting with No Conduit Sealing Fitting.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 25 OCTOBER 2025
Drywell
▪ Gas sensor in the dry well was not
functioning at the time of the inspection.
▪ Most conduit in the drywell was observed to
be galvanized rigid metal conduit, not PVCCoated galvanized rigid metal conduit. Some conduit corrosion was observed.

Wet Well
▪ City staff advised that the lighting needs to
be updated in the wet well. The City could
not determine if only bulbs need to be
replaced, or if lighting fixtures or conduit and
wire also need to be replaced.

Bar Screen
▪ Evaluation of the Bar Screen area will be
provided as part of the WWTP evaluation.

Good
Not
Observed
Not
Observed
Figure 17: Lift Station No. 3 Conduit
Corrosion at Drywell Floor
Climate Change Vulnerability Condition Photo(s)
Flooding
▪ Surrounding site grading is unpaved and
becomes muddy during precipitation events
▪ Low points in dirt around perimeter of the lift
station slab causing ponding
- Ponding water at low points and/or high
groundwater may be causing infiltration
at dry well structure joints; Infiltration
water marks observed at joints on the
interior of the dry well
Electrical Outages
▪ According to City staff, power is provided to
Lift Station #3 from the WWTP, and the
power feed is backed up by a standby
generator at the WWTP.

Extreme Heat
▪ Temperature control observed within the
electrical building.

Poor

3.1.4 Hydraulic Assessment
The Lift Station No. 3 hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with Hydraulic Institute (HI) standards. From the provided data, it was found that pumps #1, #2, and

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 26 OCTOBER 2025
#3 kick on approximately 147 times per day on average. Pumps #1 and #3 start approximately 2.1 times per hour on average with a maximum of 13 starts per hour. Pump #2 starts approximately 9 times per hour on average with a maximum of 9 starts per hour. Based on National Electric Manufacturers Association’s (NEMA) recommendations for the maximum allowable number of motor starts per hour, a 40 HP, 4-pole (1620 rpm) motor should have a maximum number of 7.4 motor starts per hour. It was observed that the instances number of starts per hour exceeds the NEMA recommended starts per hour based on the provided SCADA data. This indicates that the existing operational set points may need to be adjusted. Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 220 minutes of run time per day (3,353 total hours) while pump #2 averages approximately 216 minutes of run time per day (3,291 total hours). Pump #3 averages 223 minutes of run time per day (3.3 total hours). This data indicates that the pumps kick on with similar frequency and run times.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 feet per second (ft/s) for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Lift Station No. 3 force main is a 24” ductile iron pipe (DIP). It is unknown when the force main was installed. The existing force main is assumed to be in fair condition with no significant issues or concerns. Based on current industry standards it has a useful life of approximately 50 years. Lift Station No. 3 is a triplex lift station that operates in a lead/lag configuration. With two duty pumps in operation, the flow velocity through this existing 24” force main is estimated at approximately 2.1 ft/sec which is in accordance with HI standards.

Force Main Operation
The Lift Station No. 3 force main discharges into Main Lift Station force main, causing the two systems to pump against each other. This hydraulic conflict leads to reduced efficiency, increased wear on equipment, and inconsistent flow rates. Operations staff informed that the Lift Station No. 3 pumps only move flow effectively when operated at maximum speed, indicating high backpressure and poor system coordination. As discussed in section

3.1.2.2, two of the three original variable frequency drives (VFD) have been replaced with soft starters, enabling the City to operate the pumps as single speed pumps running at max speed. To resolve these issues, we recommend installing a second force main parallel to the existing Main Lift Station one, allowing each station to operate independently and improving overall system performance.

3.1.5 Recommended Improvements
Recommended improvements were developed for Lift Station No. 3 based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 8.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 27 OCTOBER 2025
Table 8. Lift Station No. 3 Recommended Improvements
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
E&IC Install sealing
fittings
Install conduit sealing fittings on all
conduits as they exit the hazardous
envelope (including the wet well).

Code
Violation/
Operational
Failure
Maintenance
EI&C
Perform Power
System Study
& Install Arc
Flash Stickers
Per NFPA 70E, a power system study
should be performed, and updated
every 5 years. Updates should be
made whenever modifications are
made. Arc flash stickers should be
provided on the electrical equipment.

Safety Risk
Arc Flash /
Short Circuit
Study Program
(Near-term)
EI&C
Perform thirdparty testing
on MCC and its
breakers
This is preventative maintenance that
identifies equipment issues ahead of
time. It also makes sure the breakers
are tripping at the amperage and
settings they are supposed to—to keep
staff and equipment safe.

Injury Risk/
Operational
Failure
Testing and
Studies
Program
(Near-term)
EI&C
Replace
Inoperable
Intrusion
Switches
It is recommended to install intrusion
switches for SCADA notification to
prevent unauthorized access and
tampering of lift station equipment.

Safety Risk/
Security Risk Maintenance
EI&C Replace
existing PLC
SCADA equipment is provided with an
Allen-Bradley MicroLogix PLC which is
at the end of its useful life, as it was
discontinued in 2017 by the
manufacturer.

End of Useful
Life
Instrumentation
and Control
Program –
Phase 2
(Mid-term)
EI&C
Replace
Lighting in Wet
Well
Per City Staff, lighting levels are low in
the wet well.

Safety Risk
Lift Station No.
3 Rehabilitation
(Long-term)
EI&C
Install
discharge flow
meter
Install flowmeter on pump discharge to
allow flow monitoring which provides
useful operational data and
serves as indication of diminishing
pump performance over time.

Operations
Preference
Lift Station No.
3 Rehabilitation
(Long-term)
Site Civil/
EI&C
Replace Gas
Detection
System
Gas sensor in the dry well was not
functioning at the time of the inspection.

Code
Violation/
Operational
Failure
Maintenance
Site Civil /
Climate
Change
Vulnerability
Site Grading
There are low points in the unpaved
area along the dry well where nearby
runoff ponds up. During heavy rains,
the accumulation of water in these
areas are most likely seeping down
along the exterior of the dry well
structure and infiltrating through the
concrete joints.

Preventative
Maintenance
Lift Station No.
3 Rehabilitation
(Long-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 28 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Site Civil
Install
Permanent /
Fixed Access
Ladder for Bar
Screen Motor
Bar screen motor access is in the form
of a portable ladder. It is
recommended to install a fixed ladder
with safety railings around the top so
operations staff can safely access bar
screen motor.

Risk of Injury
Lift Station No.
3 Rehabilitation
(Long-term)
Site Civil/
Mechanical
Clear Debris
within Wet Well
Walkway within the wet well has filled with
debris. Dudek was unable to inspect the
walkway or the wet well beneath the
walkway as a result.

Preventative
Maintenance Maintenance
Mechanical
Replacement
of Existing
Pump Base
(Pump #3)
Varying levels of corrosion and coating
delamination observed to be occurring on
all pumping units. Severe corrosion was
observed at Pump 3 base. Structural
integrity of pump base anchor bolts may be
at risk of failure in the near term. Seal leak
at Pump 3 is believed to be causing
accelerated corrosion.

Corrosion
Pumps, Piping,
Supports and
HVAC Program
(Mid-term)
Mechanical
Replacement
of Existing
Pumping Units
Pumps are nearing the end of useful
service life. Schedule replacement of
pumping units in the next 5 years.

End of Useful
Life
Lift Station No.
3 Rehabilitation
(Long-term)
Mechanical Routine Valve
Exercising
It is recommended to adopt a more
frequent and proactive maintenance
schedule for valve exercising.

Preventative
Maintenance Maintenance
Mechanical
Install Lift
Station Bypass
Connection
There is no existing bypass connection for
this lift station. It is recommended to install
a force main bypass connection in the
event of a lift station failure.

Increased
SSO
Potential
Force Main
Program –
Phase 1 (Nearterm)
Mechanical
Recoat Existing
Mechanical
Equipment in
Dry Well
The existing mechanical piping, valves, and
pumps within the dry well remain in good
condition, however there is minor corrosion
and coating delamination occurring in
several locations
Coating
Delamination
/ Failure
Maintenance
Mechanical
Recoat Existing
Forced Air
Ventilation
Equipment
The existing above grade forced air
ventilation blowers, piping, fittings and
blowers are experiencing varying levels of
corrosion and coating delamination.

Preventative
Maintenance Maintenance
Mechanical
Replace
Existing Sump
Pumps and
Discharge
Piping
Dry well sump pump system has failed
twice in the past.

Operational
Failure
Pumps, Piping,
Supports and
HVAC Program
(Mid-term)
Mechanical Install New
Force Main
Due to the pumping difficulties experienced
at this site it is recommended to install a
force main separate from the Main Lift
Station force main.

Operational
Failure
Force Main
Program –
Phase 1 (Nearterm)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 29 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Mechanical Routine Pump
Testing
It is recommended that the City consider
implementing routine pump performance
testing to gather data on pump
performance and to prioritize preventive
maintenance activities. Routine pump
efficiency evaluations provide valuable
information on trending of the facilities
efficiency, adequacy of installed
equipment, and electro-mechanical
condition. Since this data collection and
analysis has a cost associated with it,
routine pump performance testing is only
recommended for pump stations that
exhibit high “load factors” (i.e., significant
daily runtimes), significant motor loads,
and/or high-head operations (e.g., twostage pumping stations) Preventative
Maintenance Maintenance
Structural
Replace Wet
Well Access
Hatches
The existing wet well access hatches
are moderately corroded and the lift
assist was not working. It is
recommended to replace the access
hatches with new hatches that are
equipped with integrated fall
protection, slam lock, and lift assist.

Injury Risk/
Operational
Failure
Lift Station No.
3 Rehabilitation
(Long-term)
Structural
Wall
Penetration
Improvements
Use hydrophilic grout at all wall
penetrations to prevent water
infiltration into the dry well.

Preventative
Maintenance
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 2
(Mid-term)
Structural
Rehabilitate
Liner and Liner
Termination
within Wet Well
Rehabilitate the existing concrete at
the liner and liner terminations within
the wet well and provide improvements
to the liner terminations as-needed to
prevent accelerated corrosion of the
structure.

Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 2
(Mid-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 30 OCTOBER 2025

3.2 Gios Lift Station

3.2.1 Location and Layout
The Gios Lift Station is located at the southeast corner of the Gios Mobile Home Estates, enclosed in a concrete masonry unit (CMU) block wall outside of the public right-of-way. A chain link gate on North Waterman Avenue provides access to the Gios Lift Station. The facility can also be accessed through the Gios Mobile Home Estates.

Gios Lift Station is a compact, submersible Vaughan Chopper facility that serves the Gios Mobile Home Estates community to the south of the WWTP. The Gios lift station is owned by the mobile home park but operated by the City.

Figure 18: Gios Lift Station Location
Figure 19: Gios Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 31 OCTOBER 2025

3.2.2 System Characteristics

3.2.2.1 Pump Station
A summary of the pumping units for Gios LS is provided on Table 9, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 10.

Table 9. Gios Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Vaughan Model SE3F2
Pump Type Submersible
Design Capacity 250 gpm @ 20’ TDH
Motor, hp 5
Motor Operation Constant Speed
Speed, rpm 1750
Discharge Diameter, inches 4
Year Installed 1975; Pumps Replaced in 2016 (per provided pump cut sheet) Table 10. Gios Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete
Diameter, feet 4
Depth, feet Unknown
Floor Elevation, feet Unknown
Influent Sewer Invert, feet Unknown
Cover/Hatch Type Fiberglass Enclosure
Bypass Assembly
Valve Location N/A
Bypass Connection Yes
After reviewing the available Gios Lift Station record drawings and site investigations it was observed that there is no dedicated force main for this lift station. Two gravity influent lines enter the wet well. Flow is then pumped above grade where it passes through check valves before joining and flowing back into the wet well. It then leaves the wet well into one effluent line which flows by gravity to the nearest downstream manhole.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 32 OCTOBER 2025

3.2.2.2 Operations and Maintenance History
The wet well at Gios Lift Station is scheduled for cleaning every six months. However, operations staff reported that it is sometimes cleaned every three months, depending on conditions. During a site inspection, operations staff informed Dudek that the existing chopper pumps are planned to be replaced within two weeks of the February 11, 2025 site inspection. The existing pumps do not have lifting cables and have to be manually retrieved during removal. The lift station uses chemical dosing odor control. The dosing pumps operate every 45 minutes to an hour for about 30 to 40 seconds per cycle. The chemical storage drum typically requires refilling once per month.

3.2.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at the Gios Lift Station. Table 11 contains observations made during the February 11, 2025, site inspection and information provided by the City during the pre- and post-inspection workshops.

Table 11. Gios Lift Station Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ Site grade is crushed rock.
- Low points not observed
adjacent to wet well.
▪ Water meter and hose located
within the CMU block wall.
- Water service backflow
preventor is moderately
corroded and oxidized. Above
grade service piping is PVC.

PVC has minor chalking.
- The water meter was not
inspected while on site.
▪ Chemical dosing system located
adjacent to the wet well.
- No eye wash station located
at this site. OSHA 29 CFR
1910.151 requires eye wash
stations be located at
facilities with injurious
corrosive materials stored.
▪ No permanent/integrated fall
protection observed at wet well
access hatch.
▪ Fiberglass enclosure was
unlocked at the time of the
inspection with no intrusion
switch.

Good
Figure 21: Gios Lift Station Water Service Backflow Preventor Figure 20: Gios Lift Station Facility Site

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 33 OCTOBER 2025
Mechanical Condition Photo(s)
Pumps
▪ Submersible pumps were not
pulled for assessment during
field inspections.
▪ Pump discharge hoses are
observed to be in good condition.

Operations reported no issues
with them.
▪ No pump lifting chains at this lift
station. Operations informed they
have to “fish” for the pump bail
to remove the pumps.
▪ FOG observed in the wet well.

Good

Figure 22: Gios Lift Station Submersible Pumps
Piping and Valves
▪ Moderate to severe corrosion at
pipe support base of discharge
pipe.
- PVC discharge elbow below
coupling is at risk if pipe
supports fail.
▪ PVC discharge piping is in good
condition. Moderate chalking
observed.
▪ Operations reports no issues with
PVC check valves.
▪ PVC bypass connection located
on vertical piping beneath
discharge header.
- Camlock bypass connection.

Fair
Figure 23: Gios Lift Station Piping, Valves, and Pipe Supports

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 34 OCTOBER 2025
Structural Condition Photo(s)
Wet Well
▪ A sheet metal rim sits on top of
the precast concrete wet well.
- The fiberglass enclosure rests
on the metal rim.
- Rim was observed to have
moderate corrosion and in fair
condition.
▪ Moderate concrete spalling at the
wet well overflow pipe
penetration and around the top
of the wet well.
- Concrete sections may fall
and damage pumps.
- Operations informed that the
overflow line conveys flow to
the manhole downstream of
the force main.
▪ Moderate concrete corrosion
observed in the wet well, and
large aggregate exposed.
▪ Wet well vault is not sealed
causing surrounding environment
to a hazardous location per NFPA
820.

Poor

Figure 24: Gios Lift Station Wet Well Concrete Condition

Figure 25: Gios Lift Station Wet Well Spalling
Electrical & Instrumentation Condition Photo(s)
▪ Wet well vault did not appear to
be sealed causing surrounding
environment to a hazardous
location per NFPA 820 and NEC.
▪ Electrical equipment, including
the electrical service meter and
electrical equipment rack, was
not observed to be rated NEMA 7
but is within the hazardous
envelope because the wet well is
exposed under the fiberglass
cover, which was not observed to
be a sealed barrier. This is a
code and safety issue.

Poor
Figure 26: Gios Lift Station Open Wet Well, Adjacent Electrical Equipment, Electrical Rack

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 35 OCTOBER 2025
▪ No sealing fittings are observed
on any electrical conduits, so wet
well gases can enter electrical
equipment via conduits. Cables
appeared to exit the j-boxes
adjacent to wet well and enter
wet well directly.
▪ Numerous electrical junction
boxes were observed mounted
adjacent to the wet well and did
not appear to be NEMA 7 rated.

One of the junction boxes was
observed to swivel, but it should
not.
▪ Galvanized pipe was observed to
be used as conduit. This is a
code violation that needs to be
replaced.
▪ The City advised that they do not
have their own power source to
the lift station from the utility.

The City advised that the existing
electrical is single-phase 240-
volts from the park’s electrical
system.
▪ All electrical equipment appeared
to be old, in poor condition, and
beyond useful life. Knocked out
blank breaker spaces were
observed such that the panel
interior is exposed to personnel.
▪ One LED light fixture was
observed at the equipment rack
that appeared to be rated for wet
locations.
▪ No arc flash stickers were
observed on the electrical
equipment.
▪ No standby power generator or
portable generator connection
was observed.
▪ City staff indicated that the
pumps start and stop based on
float switches.

Figure 27: Gios Lift Station Non-Hazardous Rated Electrical Meter & J-Boxes at Wet Well

Figure 28: Gios Lift Station Galvanized Pipe Used as Electrical Conduit & Electrical Equipment Safety Concern & Equipment Condition Example

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 36 OCTOBER 2025
▪ I/O appeared to be transmitted
off site using a Mission
Communications Cellular
Wireless RTU, for the lift station.

City staff indicated that the lift
station is not on the SCADA
system.
▪ City staff advised that the Warrick
pump moisture sensors do not
work.
▪ No lift station discharge
flowmeter was observed.
▪ City staff advised that the wet
well high level float activates the
local red light but does not report
back the Mission Control RTU.
▪ No intrusion switches were
observed on site.

Climate Change Vulnerability Condition Photo(s)
Flooding
▪ Site grade is crushed rock.
- Low points not observed
adjacent to wet well.

Electrical Outages
▪ No standby generator / ATS or
portable generator receptacle
observed on site.

Extreme Heat
▪ Air cooling / temperature control
not observed inside electrical
enclosures.

Poor

3.2.4 Hydraulic Assessment
The Gios Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 1.1 times per hour on average with a maximum of 27 starts per hour. Pump #2 starts approximately 0.02 times per hour on average with a maximum of 0.6 starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 5 HP, 4- pole (1750 rpm) motor should have a maximum number of 16.3 motor starts per hour. It was observed that the instances number of starts per hour exceeds the NEMA recommended starts per hour based on the provided SCADA data.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 37 OCTOBER 2025
Pump #1 averages 106 minutes of run time per day (1,609 total hours) while pump #2 averages 2.3 minutes of run time per day (35 total hours). The difference in run time and starts per hour will unevenly wear the pumps. This may be indicative of an issue with the control logic of the pumps or an issue with the level control instrumentation.

Dudek recommends for the City Operations staff to investigate the cause of this discrepancy.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Lift Station No. 3 force main is a 4” of unknown material and believed to be installed in 1976. The condition of the force main is unknown; however, it is nearing the end of its industry standard useful life of approximately 50 years. Gios Lift station is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the flow velocity through this existing 4” force main is estimated at approximately 6.4 ft/sec which is in accordance with HI standards.

3.2.5 Recommended Improvements
Recommended improvements were developed for Gios LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 12.

Table 12. Gios Lift Station Recommended Improvements
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
EI&C/
Climate
Change
Vulnerability
Replace all
Electrical and
Controls
Equipment,
including
junction boxes,
conduit, and
wire
All equipment appeared to be in poor
condition, is within hazardous
envelope, has safety and code
violations, is beyond useful life.

Replace all electrical, controls, and
instrumentation. Install ultrasonic
level transmitter and have it control
the pumps, as appeared to be typical
with most of the City’s Lift Stations.

Install air cooling / temperature
control on the control panel.

Code
Violation/
Operational
Failure
Instrumentation
and Control
Program –
Phase 1
(Near-term)
EI&C
Locate new
Electrical/
Control
Equipment
Rack and all
electrical and
controls jboxes outside
of Hazardous
Envelope
Safety issue, code violation,
equipment failure/damage possible
in existing location.

Code
Violation/
Operational
Failure
Instrumentation
and Control
Program –
Phase 1
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 38 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
E&IC
Replace
existing
electrical
service and
pump motor
controllers
Replace existing 120/240V singlephase electrical service from park power system with w 480V threephase electrical service directly from the Utility. This service, with 480V
pumps will provide better
operational reliability, with less
downtime, anticipated less
equipment failure utilizing more
commonly available equipment. Put
in location outside of hazardous
envelope.

Operational
Failure
Instrumentatio
n and Control
Program -
Phase 2 (Midterm)
EI&C
Perform Power
System Study
& Install Arc
Flash Stickers
Per NFPA 70E, a power system study
should be performed, and updated
every 5 years Updates should be
made whenever modifications are
made. Arc flash stickers should be
provided on the electrical
equipment.

Safety Risk
Arc Flash /
Short Circuit
Study Program
(Near-term)
EI&C /
Climate
Change
Vulnerability
Install a
portable
generator
connector
This will allow the City to bring a
portable generator on site to provide
power when utility power fails.

Operational
Failure
Power and
Generator
Program
EI&C
Have high
level float
switch report
to Mission RTU
Per City staff request. Operations
Preference Maintenance
EI&C
Install
Intrusion
Switches
Intrusion switches are not currently
installed on the electrical
equipment. It is recommended to
install intrusion switches for RTU
notification to prevent unauthorized
access and tampering of lift station
equipment.

Safety
Risk/
Security
Risk
Maintenance
Site Civil
Installation of
Emergency Eye
Wash
This facility has no onsite water and
no emergency eye wash station.

OSHA 29 CFR 1910.151 requires eye
wash stations be located at facilities
with injurious corrosive materials
stored.

Injury Risk/
Operational
Failure
Gios Lift
Station
Rehabilitation
(Long-term)
Mechanical Replace Water
Service Piping
Water service backflow preventor is
moderately corroded and oxidized.

Above grade service piping is PVC.

PVC has minor chalking.

Corrosion Maintenance
Mechanical Install Pump
Lifting Chains
No pump lifting chains at this lift
station. Operations informed they have
to “fish” for the pump bail to remove the
pumps.

Operations
Preference
Gios Lift
Station
Rehabilitation
(Long-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 39 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Mechanical Pipe Support
Replacement
Moderate to severe corrosion at pipe
support base of discharge pipe
assembly. PVC discharge elbow below
coupling is at risk of failure if pipe
supports fail.

Operational
Failure Maintenance
Structural
Replace /
Redesign Wet
Well Access
Cover Plate
It is recommended to replace or
redesign the wet well access cover
plate with new hatches that are
equipped with integrated fall
protection, locking mechanism, and
lift assist.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)
Structural
Rehabilitate
Wet Well and
Install Wet
Well Liner
Moderate concrete corrosion observed
in the wet well, and large aggregate
exposed. There is currently no existing
liner within the wet well leading to
accelerated corrosion.

Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)

3.3 Main Lift Station

3.3.1 Location and Layout
The Main Lift Station is the largest lift station in the City’s wastewater system and is located at 1587 W Pico Avenue, west of North Park and east of the Humane Society of Imperial County. The lift station is a dry well/wet well facility with a large service area that includes industrial and residential areas in the City’s northern area. Site access for this facility is by a driveway and fence gate south of Pico Avenue. The lift station is secured by a perimeter fence.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 40 OCTOBER 2025
Figure 29: Main Lift Station Location
Figure 30: Main Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 41 OCTOBER 2025

3.3.2 System Characteristics

3.3.2.1 Pump Station
A summary of the pumping units for Main LS is provided on Table 13, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 14.

Table 13. Main Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Chicago Pump, Model CP8175LS
Pump Type Dry well
Design Capacity 2535 gpm @ 39’ TDH
Motor, hp 50
Motor Operation VFD
Speed, rpm 875
Discharge Diameter, inches 8
Year Installed 1935, Rehabilitated 1993, 1999, and 2007 Table 14. Main Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Lined concrete
Diameter, feet 32 x 10
Depth, feet 31.3
Floor Elevation, feet -76.75
Influent Sewer Invert, feet -72.33
Cover/Hatch Type Single-leaf hatch
Dry Well
Size, feet 23.5 x 12
Material Cast in place concrete
Depth, feet 33.33
Cover/Hatch Type Staircase within Dry Well / Electrical Building Bypass Assembly
Valve Location Dry well
Bypass Connection Above grade outside the Dry Well / Electrical Building Force Main
Diameter, inches 30
Length, feet Approximately 5,826
Material PVC

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 42 OCTOBER 2025

3.3.2.2 Operations and Maintenance History
The Main Lift Station was built in 1935. Originally it was designed as an extended shaft dry well pump station with a 27-foot wet well. In 1993, a chlorination building was installed, and the original 18-inch force main was replaced by a 27” force main. In 1999 the force main was replaced again with a 30” force main. In 2007, Main Lift Station was rehabilitated including new pumps, VFDs, and mechanical piping. Operations staff report that the flow-matching pump control causes pumps to operate without rotating until the wet well reaches the pump shutoff set point. This results in uneven pump run times. To correct this, staff must manually monitor and rotate pump operation to balance usage.

It was reported that the air release valve on the lift station bypass connection has not been maintained, and the check valve has not been exercised. Onsite observations showed that the original magnetic flow meter failed, and a clamp-on flow meter was installed just below it. Operations staff consider the clamp-on meter a temporary solution but would like a new magnetic flow meter. The temporary clamp on flow meter does not transmit to the City’s SCADA system.

The Bioxide injection odor control system was determined to be ineffective by the City and was moved to the East Side Lift Station.

Operations staff conduct monthly inspections of the bar screen vault. The vault frequently floods, which displaces the floor grates and requires them to be repositioned. Staff also report low water pressure in the bar screen system, which is believed to result from sharing a water meter with the neighboring humane society.

3.3.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at the Main Lift Station. Table 15 contains observations made during the February 11, 2025 site inspection and information provided by the City during the pre- and post-inspection workshops.

Table 15. Main Lift Station Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ Entrance to the Main Lift Station
site is through an asphalt concrete
access road off of West Pico Avenue
▪ There is an existing automatic
sliding entrance gate for vehicular
access to the site
▪ An existing chain link fence with
barbed wire and privacy slats
surrounds the site, preventing
unauthorized access
▪ Surrounding site grading is unpaved
and becomes muddy during
precipitation events

Good

Figure 31: Main Lift Station Facility Access Road and Sliding Entrance Gate

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 43 OCTOBER 2025
▪ The at-grade concrete slabs for the
various lift station structures do not
have issues with flooding/drainage
and no tripping hazards were
observed
▪ The access stairs down to the dry
well and bar screen structure have
safety handrails that remain in good
condition
▪ Various segments of bar screen
vault floor grating lifts off of frame
and falls into channel when flow
backs up and rises inside of vault
leaving large gaps in the floor which
introduce a significant safety risk for
operations staff.
- Spalling observed at bar screen
vault stairs. Safety hazard for
operations entering/ leaving
vault.
▪ The wet well access hatches are
significantly corroded and are not
safe to walk on introducing a
significant safety risk for operations
staff
- No permanent/integrated fall
protection observed at wet well
access hatch. Lift assist was not
observed to be functioning.
- No working intrusion switches or
locks on the wet well access
hatches.
▪ Approximately half of the lighting
was operable, however it was
mentioned that it was insufficient
for staff to work. Approximately half
of the upstairs lighting is inoperable,
and operations staff mentioned they
are inaccessible to change bulbs or
replace.
▪ There is an existing emergency eye
wash station on site that remains in
good condition
Figure 32: Main Lift Station Facility Sliding Entrance
Gate (From Interior)
Figure 33: Main Lift Station Dry Well Access Stairs and Handrails Figure 34: Main Lift Station Bar Screen Structure Grating

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 44 OCTOBER 2025
Figure 35: Main Lift Station Wet Well Access Hatch
Figure 36: Main Lift Station Electrical Room Lighting
Mechanical Condition Photo(s)
Pumps
▪ Three (3) dry pit submersible pumps
are located within the dry well.
- Pumps are controlled by level
transducers with float high water
alarm.
▪ Pumps located on pedestals than
are anchored to concrete
housekeeping pads. The pump
bases and concrete pads are in
good condition.
▪ Insignificant extent of minor
corrosion and coating delamination
was observed on the pumping units
▪ All flanged connections remain leaktight and in good condition

Fair /
Good
Figure 37: Main Lift Station Dry Well Pumps and Pump Bases

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 45 OCTOBER 2025
▪ Operations use monorail crane
system within electrical building
above the dry well to remove pumps
for maintenance/replacement.
▪ Two (2) submersible sump pumps
are located within the sump pit
within the dry well.
- Submersible sump pumps were
not pulled for assessment during
field inspections.

Figure 38: Main Lift Station Dry Well Submersible Sump Pumps Bar Screens
▪ It was observed that the bar screen
motor can only be accessed by a
standard ladder (unfixed). No safety
railings at the top of the bar screen.
▪ Old equipment framing within
“Back-up Bar Screen Structure” is
significantly corroded; corroded
metal can fall into channel.
▪ H2S gas smell is noticeably present
at the bar screen location at grade
level. There are gaps of a couple of
inches in the concrete structure all
around the enclosed bar screen.

With these gaps, the screen area
would be classified similar to a
screen over an open channel
outdoors as a Class 1, Division 2
hazardous location for 10 feet all
around the opening.

Fair
Figure 39: Main Lift Station Bar Screen System
Figure 40: Main Lift Station Bar Screen System

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 46 OCTOBER 2025
Piping and Valves
▪ The existing above-grade bypass
connection assembly appeared to
be in fair to good condition, however
the bypass connection air valve and
check valve have not been
exercised or maintained
▪ Staff reports that the existing
magnetic flowmeter element is
inoperable and needs to be
replaced
- A retrofitted clamp on flow meter
is installed directly below the
magnetic flow meter. Operations
staff indicated that this is an
acceptable short term flow
measurement system.
▪ Piping was observed to be in good
condition.
▪ Pump discharge valves appeared to
be in good condition. Little to no
corrosion and coating delamination
was observed. Signs of insignificant
amounts of oil leaking was observed
on some of the plug valves
▪ Sump pump piping is deteriorated
and inadequately supported.

Appears to be missing pipe
supports. Only pipe support is a
wooded block located at the tee.
▪ Sump pump isolation valves and
fittings are severely corroded with
observed loss of material thickness
and degradation structural integrity
▪ Wooded blind flange observed at old
force main alignment.

Good
Figure 41: Main Lift Station Bypass Connection Assembly Figure 42: Main Lift Station Discharge Flow Meter
Figure 43: Main Lift Station Pump Discharge Valves

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 47 OCTOBER 2025
Figure 44: Main Lift Station Sump Pump Discharge Valves and Fittings
Odor Control/Ventilation
▪ The wet well odors are emitted
through an above grade PVC
standpipe which remains in good
condition
- The segment of the standpipe
that penetrates through the wet
well top slab is in fair to poor
condition
▪ The mitered 90-degree bend at the
top of the swamp cooler air inlet
duct is disconnected and is likely
not functioning as intended to
provide clean, cool air down into the
dry well
▪ Bar screen valve vault only has a
forced air inlet fan and does not
have a dedicated exhaust vent or air
exhaust fan
- Air is pumped into vault from
ceiling but may be short
circuiting out of opening around
bar screen penetration at grade.
▪ The bioxide injection station is
constructed of primarily PVC and the
piping, valves, and fittings remain in
good condition
- Operations staff mentioned that
the bioxide injection station was
not effective at Main Lift Station
and was moved to a different lift
station
▪ The external low-flow water supply
system and surge tanks remain in
fair to good condition with minor
Good
Figure 45: Main Lift Station Odor Exhaust Standpipe
Figure 46: Main Lift Station Swamp Cooler Air Inlet Duct within Electrical Building/Dry Well

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 48 OCTOBER 2025
levels of corrosion on some of the
valves and fittings
Figure 47: Main Lift Station Bioxide Injection Station
Figure 48: Main Lift Station Low-Flow Water Supply System and Surge Tanks

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 49 OCTOBER 2025
Standby Generator
▪ Staff reports that the existing
standby generator burns a gallon of
oil per month. Staff also stated that
the engine for the generator was
manufactured outside of the United
States, so parts availability and lead
time is a concern.
▪ Some of the exterior piping
connected to the standby generator
are moderately corroded and
showing signs of oxidation.

Fair
Figure 49: Main Lift Station Standby Generator Exterior Piping Figure 50: Main Lift Station Pad-Mounted Emergency
Standby Generator
Structural Condition Photo(s)
Dry Well
▪ The existing pipe supports within the
dry well remain in good condition
▪ All equipment anchorage within the
dry well appeared to remain in good
condition with no signs of damage
▪ The structural concrete/CMU block
walls were observed to be intact
however there were some areas
where minor cracking is occurring
▪ Based on discussions with the City,
the dry well structural integrity is a
concern
- Seismic evaluation of lift station
structure has not been
conducted.
- Heavy corrosion near electrical
services on bottom floor.
- Walls on bottom floor near
pumps are cracking and
delaminating.

Good

Figure 51: Main Lift Station Pump Discharge Supports

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 50 OCTOBER 2025

Figure 52: Main Lift Station Dry Well Structure
Figure 53: Main Lift Station Minor Cracking of Dry Well Walls Figure 54: Main Lift Station Cracking of Concrete Floor Near Pump Bases

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 51 OCTOBER 2025
Wet Well
▪ The existing wet well top slab was
observed to be in fair condition.
- The above-grade exterior
segment of the top slab was in
good condition with no signs of
degradation
- The bottom of the top slab was
observed to be moderately
damaged with signs of moderate
to severe corrosion of the
concrete, leading to large
aggregate being exposed and
concrete spalling
▪ The wet well access hatches are
significantly corroded and the spring
lift assist is broken in several places
▪ The existing wet well liner is in fair
condition with varying levels of
delamination and degradation
- Unable to determine concrete
condition behind liner.
▪ The existing wet well liner was
compromised at the wet well access
hatch openings. Acidic moisture can
buildup and migrate behind the liner
causing it to bubble and peel away
from the concrete resulting in
accelerated corrosion of concrete
▪ Sealing fittings were not observed
on site. Conduits exiting the wet
well should have sealing fittings
installed on them to prevent gases
from entering electrical equipment
and non-hazardous areas in
accordance with NEC 500 and NFPA
820
Fair

Figure 55: Main Lift Station Wet Well Top Slab

Figure 56: Main Lift Station Wet Well Access Hatches

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 52 OCTOBER 2025
Figure 57: Main Lift Station Concrete Wet Well Structure Interior Figure 58: Main Lift Station Deteriorating Wet Well Liner Figure 59: Main Lift Station Compromised Wet Well Liner at Access Hatch Openings

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 53 OCTOBER 2025
Electrical Building
▪ The electrical building exterior and
interior are in good condition
▪ The existing access stairs and
handrails within the electrical
building are in good condition with
no signs of damage
▪ The existing monorail and hoist are
in good condition
Good
Figure 60: Main Lift Station Electrical/Controls Building Figure 61: Main Lift Station Interior of the
Electrical/Controls Building
Figure 62: Main Lift Station Access Stairs to Bar Screen Vault

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 54 OCTOBER 2025
Bar Screen Vault
▪ Bar screen vault door frame
severely corroded and inoperable
▪ Spalling observed at bar screen
vault stairs. Safety hazard for
operations entering/ leaving vault
▪ Some of the pipe supports/clamps
are experiencing moderate to
severe corrosion
▪ Cracking of the concrete ceiling was
observed
▪ Degradation of concrete at the roof
access hatch opening
Poor
Figure 63: Main Lift Station Bar Screen Vault Access Door Frame Figure 64: Main Lift Station Pipe Clamp within Bar Screen Vault Figure 65: Main Lift Station Concrete Degradation of
Bar Screen Vault Ceiling

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 55 OCTOBER 2025
Electrical & Instrumentation Condition Photo(s)
General / Site
▪ Staff reported that approximately
half of the existing lighting on the
electrical/drywell building exterior
has not been replaced with LED
light fixtures.
▪ Staff reported that the existing
natural gas-powered standby
generator burns a gallon of oil per
month. Staff also stated that the
engine for the generator was
manufactured outside of the United
States, so parts availability and lead
times are a concern.
▪ The standby generator visually
appeared to be in good condition.
▪ Some of the exterior piping
connected to the standby generator
appeared to be moderately
corroded and showing signs of
oxidation.
▪ Staff advised that they run the
generator monthly with a load bank.
▪ Staff advised that the generator is
sized sufficiently for the site
electrical load.
▪ The utility pole feeding the site
appeared to be leaning significantly.

The pole could break during a
significant wind or weather event, as
it appeared to be succumbing to the
tension from the cables. Note that
the stadium light pole in the photo is
perpendicular to the ground.
▪ Intrusion switches were not
observed on site.

Fair
Figure 67: Main Lift Station Standby Natural
Gas Generator
Figure 66: Corroded Generator Piping (Left), Leaning
Utility Pole (Right)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 56 OCTOBER 2025
Wet Well
▪ Sealing fittings were not observed
on site. Conduits exiting the
hazardous areas should have
sealing fittings installed on them to
prevent gases from entering
electrical equipment and nonhazardous areas in accordance with NEC 500 and NFPA 820.
▪ City staff advised that the wet well
supply fan has been abandoned.
▪ A NEMA 4X stainless steel enclosure
was observed mounted to the top of
the wet well deck, for what
appeared to be level instruments,
with conduits exiting to the wet well
below with no sealing fittings. Since
no exposed conduits were observed
exiting the enclosures above the
deck, it is possible that some
conduits are embedded in the deck
slab on their way back to the
electrical building. Without the
presence of sealing fittings, the
enclosures should be rated NEMA 7
for hazardous locations.
▪ Mounting of instrumentation within
the wet well could not be
observed.

Fair
Figure 68: Main Lift Station Electrical Enclosure Conduits Without Sealing Fittings
Electrical & Drywell Building
▪ Emergency lighting was not
observed within the electrical and
drywell building.

Upper Level—Electrical Area:
▪ The existing Utility meter Service
Entrance Section (SES) with main
breaker has a manufacturer date of
11/04/92 on its nameplate.

Therefore, this equipment has
reached the end of its useful life. It
is assumed that the MCC was
installed at the same time as the
SES.
▪ Staff reports that the ATS was
replaced 6 months ago. A new ATS
was observed installed inside the
old ATS’s section in the MCC. As
long as there is no live exposed bus
bar in the section, this installation
did not appear to violate code. Bus
Fair

Figure 69: Main Lift Station Existing Utility Meter SES, ATS, and MCC

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 57 OCTOBER 2025
bar was not observed. The old ATSs
section door had to be opened to
access the front of the new ATS and
its keypad and screen. Only the old
ATS controller and status lights are
visible on the front of the MCC,
which are no longer active.
▪ The MCC appeared to originally
house the motor controllers for the
lift station pumps. Modifications
were made to install three VFDs
with bypass contactors in a standalone enclosure adjacent to the MCC. The existing MCC buckets
were used for their breakers to feed
power to each VFD.
- Should staff need to work in the
VFD panel, the power to all three
pumps would need to be shut
down and no lift pumps could
operate.
- Should there be a fault or some
other electrical event in the VFD
panel that creates damage that
prevents all three VFDs from
running, the three lift pumps
would be inoperable until repairs
are complete.
- The VFD panel has a dedicated
A/C unit and ductwork into the
top of the panel to keep the
VFDs cool. There is no A/C for
the rest of the building.
- The VFDs are likely at the end of
their useful life and acquiring
parts may become difficult.
▪ There is a 3-foot-wide control panel
between the MCC and the VFD
panel that has 33 600V rated relays
to run motors, but City staff advised
that only 4 relays are in operation to
run 4 pieces of equipment on site.

Keeping this panel in service with
abandoned and operating
equipment can create confusion,
which could lead to an event or
injury.
▪ City staff reported that the existing
lift station pump discharge magnetic
flowmeter has failed. Staff installed

Figure 70: Main Lift Station Newer ATS & Controller Inside Old ATS’s MCC Section Behind Door
Figure 71: Main Lift Station VFD Enclosure with
Three Lift Pump VFDs

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 58 OCTOBER 2025
a strap-on doppler flow meter to
take its place as an interim solution.
▪ City staff advised that the ultrasonic
lever transmitter commands the lift
pumps to start and stop, and the
doppler flow transmitter commands
VFD speed of the lift pumps to
maintain a flow setpoint.
▪ City staff advised that the bioxide
system transformer and panelboard
located on the wall to the left of the
VFD panel is abandoned and can be
removed.
▪ Lighting on the upper level for the
electrical equipment appeared
operable.
▪ No arc flash stickers were observed
in the electrical building, or
anywhere on site.
▪ No third-party maintenance/testing
stickers were observed on the
electrical equipment.
▪ I/O appeared to be transmitted off
site using a Mission
Communications Cellular Wireless
RTU, for the lift station.
▪ Per City staff, the wet well high level
signal is transmitted off site via
separate land phone line.

Mid Level—Pump Disconnects:
▪ None of the lighting appeared to be
operable on middle level. Staff
stated they cannot access the light
fixtures to replace bulbs and light
fixtures.

Lower Level—Pump Area:
▪ The drywell lower level is
insufficiently lit to work with a
significant amount of lights not
working. Even if all lights were
working in the lower level, it
appeared to be insufficient to work.
▪ The sump pump control panels are
very small for a control panel, and
the control panels and associated
electrical appeared to be in poor
condition.

Figure 74: Main Lift Station Existing Drywell
Sump Pump Control Panels
Figure 72: Main Lift Station Control Panel with 33 Contactors (Four are in Use)
Figure 73: Example of Height of Existing Middle Level Lighting

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 59 OCTOBER 2025
Bar Screen Area & Vault
▪ H2S gas smell was strong at the bar
screen area at grade level. Gaps of
a few of inches in the concrete
structure were observed all around
the enclosed bar screen. There was
also no solid door at the screen
vault entrance at the bottom of the
stairs. Considering both the gaps
around the screen and the open
vault entry, the screen area at grade
would be classified similar to a
screen over an open channel
outdoors as a Class 1, Division 2
hazardous location for 10 feet in all
directions around the openings and
vault door.
▪ No electrical and controls
equipment at grade level appeared
to be rated NEMA 7 for use in a
hazardous location but are all within
the 10 foot envelope of the gaps
around the bar screen, including the
control panel, lighting, emergency
stop button, and receptacles.
▪ A ventilation fan was observed
adjacent to the control panel. Could
not determine if its motor(s) and
electrical is rated for use in a
hazardous location.
▪ Two light fixtures were observed
within the 10-foot hazardous
envelope around the bar screen and
are not hazardous location rated.

One fixture is mounted to the
control panel strut, and the second
is mounted to the bar screen itself.
▪ Broken conduits and stretched
exposed conductors were observed
at both ends of the conduits
between the electrical/drywell
building and the bar screen area.

This is likely due to ground settling,
as the break and gaps in the
conduits appeared to be
approximately two inches.
▪ Sealing fittings at grade level were
observed on only two conduits going
between the bar screen control
panel and the concrete slab. No
sealing fittings were observed on
Poor
Figure 75: Main Lift Station Large Gaps Around Bar Screen Figure 76: Main Lift Station Electrical, Screen Control Panel, Conduits, Light (Not Hazardous-Rated)

Figure 77: Main Lift Station Broken Conduits: At Electrical Building (Left), At Bar Screen (Right)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 60 OCTOBER 2025
any other conduits at grade level in
the bar screen area. Conduits
exiting hazardous areas associated
with the bar screen and bar screen
vault should have sealing fittings
installed on them to prevent gases
from entering electrical equipment
and non-hazardous areas in
accordance with NEC 500 and NFPA
820.
▪ Lighting fixtures inside the bar
screen vault did not appear to be
rated for a Class 1, Division 1
hazardous location, but were
inaccessible to read their nameplate
to verify. If they are not properly
rated, they should be replaced.
▪ The bar screen vault appeared to
have previously flooded high enough
to submerge conduits on the walls.
▪ Some conduit corrosion was noted
within the vault, but did not appear
to have corroded through the
conduits.

Figure 78: Main Lift Station Typical Bar Screen Vault Light Fixture Figure 79: Main Lift Station Water Line on Wall Indicating Previous Flood Level
Climate Change Vulnerability Condition Photo(s)
Flooding
▪ Surrounding site grading is unpaved
and becomes muddy during
precipitation events
▪ The at-grade concrete slabs for the
various lift station structures do not
have issues with flooding/drainage
and no tripping hazards were
observed
Electrical Outages
▪ The standby generator visually
appeared to be in good condition.

Extreme Heat
▪ The VFD panel has a dedicated A/C
unit and ductwork into the top of the
panel to keep the VFDs cool. There
is no A/C for the rest of the building.

Good

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 61 OCTOBER 2025

3.3.4 Hydraulic Assessment
The Main Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 0.1 times per hour on average with a maximum of 56 starts per hour. Pump #2 starts approximately 0.1 times per hour on average with a maximum of 5 starts per hour.

Pump #3 starts approximately 0.1 times per hour on average with a maximum of 7 starts per hour. All three pumps average the same starts per hour. It is assumed that Pump 1 had a malfunction during the hour which it started 56 times on 8/17/22. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 50 HP, 6-pole (875 rpm) motor should have a maximum number of 7.7 motor starts per hour. All three pumps are in compliance with the NEMA recommended number of pump starts per hour.

Pump #1 averages 421 minutes of run time per day (6,414 total hours) while pump #2 averages approximately 336 minutes of run time per day (5,122 total hours). Pump #3 averages 731 minutes of run time per day (11,141 total hours). This data indicates that the pumps kick on with similar frequency however their run times vary greatly.

The difference in run time may unevenly wear the pumps.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Main Lift Station force main is a 30” PVC pipe installed in 1999. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. Main Lift Station is a triplex lift station. With two duty pumps in operation, the flow velocity through this existing 30” force main is estimated at approximately 2.3 ft/sec which is in accordance with HI standards.

3.3.5 Recommended Improvements
Recommended improvements were developed for Main LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 16.

Table 16. Main Lift Station Recommended Improvements
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
EI&C
Replace existing
drywell/electrical
building interior
and exterior
lighting
completely
Replace outdoor lighting to
improve light levels and energy
savings. Replace indoor lighting
with better light levels, LEDs to
save energy, and fixtures that
can be accessed for
maintenance and replacement
on all three level.

Safety Risk/
Security Risk
Main Lift
Station
Rehabilitation
(Mid-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 62 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
EI&C Install emergency
lighting
Install emergency lighting in
electrical/drywell building and
screen vault.

Safety Risk
Main Lift
Station
Rehabilitation
(Mid-term)
E&IC/
Climate
Change
Vulnerability
Replace existing
generator
Replace the permanent
generator with a new generator
that has an engine manufactured
in the USA and more readily
available replacement parts.

Operational
Failure
Main Lift
Station
Rehabilitation
(Mid-term)
EI&C Repair corroded
generator piping
Repair corroded piping for the
standby generator
Preventitive
Maintenance
Power and
Generator
Program
(Near-term)
EI&C
Replace Utility
power pole
feeding the site
Request the Utility replace the
leaning power pole that powers
the site—to prevent an
unplanned outage due to a
weather or wind event breaking
or toppling the pole.

Operational
Failure
Power and
Generator
Program
(Near-term
EI&C Install sealing
fittings
Install conduit sealing fittings on
all conduits as they exit the
hazardous envelope (including
the wet well, screen vault, and
screen area at grade) and before
they enter any enclosures or
junction boxes.

Code
Violation/
Operational
Failure
Maintenance
EI&C
Replace
discharge
magnetic flow
meter
Replace flowmeter on pump
discharge to allow flow
monitoring which provides useful
operational data and serves as
indication of diminishing pump
performance over time.

Magnetic flowmeters are typically
more accurate than strap-on
doppler flowmeters.

Operations
Preference Maintenance
E&IC Install intrusion
switches
Install intrusion switches and
have them report to the RTU. Safety Risk/
Security Risk Maintenance

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 63 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
EI&C
Replace VFD
enclosure with
three new VFD
enclosures
Replace single enclosure with
three LS pump VFDs with three
enclosures with one LS pump
VFD in each. To make room in
the electrical building, the 3-foot
control panel with 33 contactors
will need to be removed, as will
the bioxide transformer and
panel board. Starter buckets can
be installed in space in the MCC
to run the equipment still being
operated by the 3-foot control
panel.

Operational
Failure
Instrumentati
on and
Control
Program –
Phase 1
(Near-term)
EI&C
Replace the
existing SES, ATS
section, and MCC
completely
Recommend planning to replace
these within 5 years—they are
already at the end of their useful
life.

End of Useful
Life
Main Lift
Station
Rehabilitation
(Mid-term)
EI&C
Replace sump
pump electrical,
instruments, &
control panels
Replace all and put new sump
pump control panels on the
middle level—staff request.

Operational
Failure
Instrumentati
on and
Control
Program –
Phase 1
(Near-term)
EI&C
Perform Power
System Study &
Install Arc Flash
Stickers
Per NFPA 70E, a power system
study should be performed, and
updated every 5 years Updates
should be made whenever
modifications are made. Arc flash
stickers should be provided on the
electrical equipment.

Safety Risk
Arc Flash /
Short Circuit
Study Program
(Near-term)
EI&C
Perform thirdparty testing on
MCC and its
breakers
This is preventative maintenance
that identifies equipment issues
ahead of time. It also makes sure
the breakers are tripping at the
amperage and settings they are
supposed to—to keep staff and
equipment safe.

Injury Risk/
Operational
Failure
Testing and
Studies
Program
(Near-term)
EI&C
Relocate all
control panels,
electrical,
lighting, and
receptacles
outside the 10-
foot hazardous
area1
Relocate all non-hazardous location
rated equipment at the bar screen
on grade level outside of the
hazardous envelope, including the
control panel, lighting, emergency
stop button, and receptacles.

Code
Violation/
Operational
Failure
Maintenance

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 64 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
EI&C
Replace Bar
Screen E-stop
with NEMA 7
Replace Emergency stop button
mounted to the bar screen with a
NEMA 7 rated button.

Code
Violation/
Operational
Failure
Instrumentati
on and
Control
Program –
Phase 1
(Near-term)
EI&C
Repair broken
conduits for bar
screen exiting
drywell/electrical
building
Safety hazard and risk of breaking
of conductors, interrupting
operations.

Code
Violation/
Operational
Failure
Instrumentati
on and
Control
Program –
Phase 1
(Near-term)
EI&C
Repair broken
conduits for bar
screen at the bar
screen area
Safety hazard and risk of breaking
of conductors, interrupting
operations. Recommend
intercepting conduits below grade
and extending to new bar screen
control panel location per
recommendation above.

Code
Violation/
Operational
Failure
Maintenance
EI&C
Replace bar
screen vault
lighting and
repair conduits
Replace bar screen vault lighting
fixtures if they are not rated for a
Class 1, Division 1 hazardous
location. Repair conduits as
needed—some due to corrosion,
some due to prior submergence.

Code
Violation/
Operational
Failure
Maintenance
EI&C Replace lighting
at bar screen1
Existing lighting is not hazardous
location rated and appeared to be
in a hazardous envelope. Replace
with NEMA 7 rated fixtures, or
relocate outside the hazardous
envelope. Evaluate lighting level in
the area and add lighting if needed.

Code
Violation/
Operational
Failure
Maintenance
Site Civil
Replace Floor
Grating within
Bar Screen Vault
Various segments of bar screen
vault floor grating has fallen into
channel when flow backs up and
rises inside of vault leaving large
gaps in the floor which introduce a
significant safety risk for operations
staff.

Safety Risk/
Security Risk
Main Lift
Station
Rehabilitation
(Mid-term)
Site Civil
Repair Access
Stairs to Bar
Screen Vault
Concrete spalling of the access
stairs leading to the bar screen
vault poses a tripping/safety
hazard for operations staff. It is
recommended to repair the
access stairs where spalling is
occurring.

Concrete
Degradation
Main Lift
Station
Rehabilitation
(Mid-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 65 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Site Civil
Install Permanent
/ Fixed Access
Ladder for Bar
Screen Motor
Bar screen motor access is in the
form of a portable ladder. It is
recommended to install a fixed ladder
with safety railings around the top so
operations staff can safely access bar
screen motor.

Risk of Injury
Main Lift
Station
Rehabilitation
(Mid-term)
Site Civil
Replace Bar
Screen Vault
Door
The bar screen vault door frame
is severely corroded making the
access door inoperable
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program -
Phase 1
Mechanical
Recoat Existing
Mechanical
Equipment in Dry
Well
The existing mechanical piping,
valves, and pumps within the dry
well remain in good condition,
however there is minor corrosion
and coating delamination
occurring in several locations
Coating
Delamination
/ Failure
Maintenance
Mechanical
Replace Existing
Sump Pumps and
Discharge Piping
Although the existing sump
pumps were not pulled for
inspection, it is anticipated that
they are at or near the end of
their useful life and in need of
replacement. The existing
discharge piping, valves, and
fittings are experiencing severe
corrosion and need to be
replaced.

End of Useful
Life
Main Lift
Station
Rehabilitation
(Mid-term)
Mechanical Routine Valve
Exercising
The existing bypass connection
air valve and check valve have
not been exercised or
maintained. It is recommended
to adopt a more frequent and
proactive maintenance schedule
for valve exercising.

Preventative
Maintenance Maintenance
Mechanical Replace Existing
Flowmeter
City operations staff report that the
existing magnetic flowmeter element
is inoperable and needs to be
replaced.

Operational
Failure
Main Lift
Station
Rehabilitation
(Mid-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 66 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Mechanical
Repair Forced Air
Ventilation
System within Dry
Well and
Electrical
Building
The mitered 90-degree bend at the
top of the forced air ventilation inlet
ducting is disconnected and is likely
discharging mostly within the
electrical building
Operational
Failure
Main Lift
Station
Rehabilitation
(Mid-term)
Mechanical Routine Pump
Testing
It is recommended that the City
consider implementing routine
pump performance testing to gather
data on pump performance and to
prioritize preventive maintenance
activities. Routine pump efficiency
evaluations provide valuable
information on trending of the
facilities efficiency, adequacy of
installed equipment, and electromechanical condition. Since this data collection and analysis has a
cost associated with it, routine
pump performance testing is only
recommended for pump stations
that exhibit high “load factors” (i.e.,
significant daily runtimes),
significant motor loads, and/or highhead operations (e.g., two-stage pumping stations)
Preventative
Maintenance Maintenance
Mechanical
Redesign Forced
Air Ventilation
System at Bar
Screen Vault
Bar screen vault only has an air
intake fan and does not have an air
exhaust fan. Clean air is blown into
the vault but may be short circuiting
out of opening around bar screen
penetration through vault top slab
at grade.

Operational
Failure
Main Lift
Station
Rehabilitation
(Mid-term)
Mechanical
Replace Existing
Standby
Generator
Staff reports that the existing
standby generator burns a gallon of
oil per month. Staff also stated that
the engine for the generator was
manufactured outside of the United
States, so parts availability and lead
time is a concern.

N/A Maintenance
Mechanical
Replace wooden
“blind flange”
with ductile iron
blind flange
The existing wooden blind flange
does not properly seal the
abandoned pipe and is a safety
hazard.

Injury Risk/
Operational
Failure
Maintenance

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 67 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Structural Replace Wet Well
Access Hatches
The existing wet well access
hatches are significantly
corroded and are not safe to
walk on. It is recommended to
replace the access hatches with
new hatches that are equipped
with integrated fall protection,
slam lock, and lift assist.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program -
Phase 1
(Near-term)
Structural Dry Well Seismic
Evaluation
The structural integrity of the dry
well is a concern and based on
discussions with the City, a
seismic evaluation of lift station
structure has not been
conducted.

Code
Violation/
Operational
Failure
Testing and
Studies
Program
(Near-term)
Structural
Rehabilitate Liner
Termination
within Wet Well
Rehabilitate the existing
concrete at the liner
terminations within the wet well
and provide improvements to the
liner terminations as-needed to
prevent accelerated corrosion of
the structure.

Operational
Failure
Main Lift
Station
Rehabilitation
(Mid-term)

1. Should the City address electrical code violations and seal all penetrations and conduits at bar screen, this recommendation would not be required.

3.4 Countryside Lift Station

3.4.1 Location and Layout
The Countryside Lift Station is located northeast of the intersection of Highway 86 and Willow Bend Drive, within a small, fenced site. The lift station is a self-priming duplex station with lift up fiberglass enclosure that serves the Countryside residential community located to the southeast. This facility is located within a CMU block wall with a chain-link access gate on its west side near Highway 86. Parking for this site is located on Willow Bend Drive or just outside of the facility fence. The City informed Dudek that this lift station will be taken offline next year, and that the new Southern Lift Station handle the demand seen at Countryside Lift Station.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 68 OCTOBER 2025
Figure 80: Countryside Lift Station Location
Figure 81: Countryside Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 69 OCTOBER 2025

3.4.2 System Characteristics

3.4.2.1 Pump Station
A summary of the pumping units for Countryside LS is provided on Table 17, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 18.

Table 17. Countryside Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Barrett Pump Pioneer P6
Pump Type Self Priming
Design Capacity 550 gpm @ 45’ TDH
Motor, hp 15
Motor Operation Constant Speed
Speed, rpm 1100
Discharge Diameter, inches 4
Year Installed 2002
Table 18. Countryside Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Reinforced concrete
Diameter, feet 10
Depth, feet 25
Floor Elevation, feet -54
Influent Sewer Invert, feet -41.8
Cover/Hatch Type 36” manhole
Bypass Assembly
Valve Location Above grade fiberglass enclosure.

Bypass Connection None
Force Main
Diameter, inches 6”
Length, feet 5,390
Material HDPE and PVC

3.4.2.2 Operations and Maintenance History
Operations staff informed that the pumps receive regular maintenance as a part of operation’s maintenance schedule. Historically Operations reported oil leakage from pump, however this issue was resolved. Operations also

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 70 OCTOBER 2025
indicated that the check valves at this site have experienced ragging issues in the past but regular valve maintenance keeps the ragging issues to a minimum. No other ragging issues were reported at this site.

Chemical dosing is used at this facility. A 500-gallon tote of SulFade Commander is automatically injected into the wet well. Operations informed that when half of the SulFade Commander tote has been dosed into the wet well, Operations staff manually adds half a 55-gallon drum of Magnesium Oxide to the wet well.

3.4.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at the Countryside Lift Station. Table 19 contains observations made during the February 11, 2025 site inspection and information provided by the City during the pre- and post-inspection workshops.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 71 OCTOBER 2025
Table 19. Countryside Lift Station Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ Site grade is crushed rock.
▪ Water meter and hose located
within the CMU block wall.
- Backflow preventor was
observed to be above grade and
experiencing moderate
corrosion. Backflow assembly is
supported by existing galvanized
steel piping with hose clamps.
- Above grade service piping is
PVC. PVC has minor chalking.
- Water meter was not inspected
while on site.
▪ Chemical dosing system located
adjacent to the wet well.
- No eye wash station located at
this site. OSHA 29 CFR
1910.151 requires eye wash
stations be located at facilities
with injurious corrosive
materials stored.
▪ No permanent/integrated fall
protection at wet well access
manhole.
▪ Fiberglass enclosure was unlocked
at the time of the inspection with no
intrusion switch.
▪ The only security incident reported
at this lift station was one
occurrence of theft of water from
the water meter.
▪ The only lighting observed onsite
was within the fiberglass enclosure.

Fair/Good
Figure 83: Countryside Lift Station Water Backflow Preventer Mechanical Condition Photo(s)
Pumps
▪ Self-priming pumps are in good
condition.
- Minor corrosion and coating
delamination observed at
flanges.

Good
Figure 84: Countryside Lift Station Self-Priming Pump and Motors Figure 82: Countryside Lift Station Site

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 72 OCTOBER 2025
Piping and Valves
▪ Above grade ductile iron discharge
piping and valves are in good
condition.
- Discharge piping and valves are
located within the above grade
fiberglass enclosure.
- Mild corrosion and coating
delamination observed. Rate of
corrosion may be accelerated by
exposure to H2S in wet well
vapors.
- Custom (non-standard) ductile
iron bends observed at pump
discharge.
▪ PVC pump suction piping within wet
well. Piping transitions to ductile
iron after leaving the wet well.
▪ Force main fitting within the wet
well is severely corroded. Potential
for catastrophic failure.
▪ No bypass connection observed.

Fair/Good
Figure 85: Countryside Lift Station Piping and Valves
Structural Condition Photo(s)
Wet Well
▪ Wet well access manhole frame
and cover were observed to be
moderately corroded providing a
safety risk for operations.
▪ Wet well concrete is cracked and
spalling.
▪ Liner observed to be failing
throughout the wet well.
- Liner is sagging severely at the
top of the wet well.
- Liner was observed to have
extensive delaminating at the
bottom of the wet well.
- Liner failure at various locations
on the wet well wall.

Poor

Figure 86: Countryside Lift Station Wet Well Access

Figure 87: Countryside Lift Station Failing Wet Well Liner

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 73 OCTOBER 2025
Liner can fail in sheets and clog
the pump.
- Concrete behind the liner was
observed to be moderately to
severely corroded.
▪ There are no conduit seal offs
installed on conduits leaving the
wet well, and there are penetrations
between the between the wet well
and the enclosure above that are
not sealed, causing the enclosure
area to be considered a Class 1 Div
1 . Hazardous area. Neither the
motors or the electrical and
controls equipment within the
enclosure are rated for a Class 1,
Division 1 hazardous location. H2S
gas corrosion was observed in the
motor control panel.

Figure 88: Countryside Lift Station Conduit Penetration Electrical & Instrumentation Condition Photo(s)
▪ The pumps and electrical/controls
equipment we observed to be on
top of the wet well deck under a
fiberglass enclosure. The
equipment did not appear to be
rated for a hazardous location and
appeared to be at the end of its
useful life.
▪ No sealing fittings were observed
on any conduits on site but are
required per the National Electrical
Code and California Electrical Code
on conduits once they leave a
hazardous area, such as the wet
well. A lack of sealing fittings is a
safety hazard, a risk for equipment
damage, and is likely the reason for
H2S gas entering the electrical
equipment.
▪ H2S corrosion inside the electrical
equipment was reported by City
staff and appeared to be present in
the pump control panel enclosure.
▪ A junction box in the pump area
mounted to the top of wet well deck
was observed to have a cover that
was not bolted down. Inside the
junction box, there were conduit
openings that appeared to go
directly into the wet well. This can
Poor

Figure 89: Countryside Lift Station Junction Box with Conduits Directly to Wet Well and Unbolted Cover

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 74 OCTOBER 2025
allow H2S gas to travel through the
conduits.
▪ The existing level transducer
appeared to be hanging from its
cable in the wet well, which can
cause premature failure of the
cable.
▪ The penetration through the wet
well deck for the level transducer
appeared to be approximately 4-
inches in diameter and covered by
a thin metal plate that rests on the
concrete. The metal plate and
conduit can be easily lifted. H2S
gas could escape the wet well
through this penetration.
▪ The level transducer penetration
appeared to be approximately one
foot from the pump/electrical
enclosure. This short distance
could lead to an interpretation that
the pump and electrical equipment
enclosure is within a hazardous
envelope.
▪ The wet well manhole appeared to
be approximately 3 feet from the
pump/electrical enclosure. Should
the manhole not seal completely,
the manhole proximity could put the
pump/electrical enclosure within a
hazardous envelope.
▪ City staff advised that the high-level
float switch is inoperable and does
not report to the RTU or back to the
WWTP via the phone line that is
present.
▪ City staff indicated that the pumps
start and stop based on signals
from the level transmitter.
▪ Lift Station I/O appeared to be
transmitted off site using a Mission
Communications Cellular Wireless
RTU.
▪ An air supply fan and an exhaust
vent were observed inside the
pump/electrical enclosure.
▪ Existing electrical service was
observed to be 240-volts, threephase, 200 amps.

Figure 90: Countryside Lift Station Level Sensor Mounting and Opening to Wet Well

Figure 91: Countryside Lift Station Broken Power Conduit from Utility Meter as it Enters the Green Fiberglass Enclosure

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 75 OCTOBER 2025
▪ The latch on the electrical meter
main breaker cover appeared to be
broken.
▪ An open conduit pointing up the
utility pole near the electrical meter
did not appear to be sealed to
prevent water entry.
▪ The conduit from the electrical
service as it enters the
pump/electrical equipment
enclosure appeared to be broken
and the conductors visible.
▪ No arc flash stickers were observed
on the electrical equipment.
▪ No standby power generator or
portable generator connection was
observed.
▪ The flexible conduits on site
appeared to be in fair condition, but
appeared to be degrading due to
exposure to the sun and elements.
▪ Rubber hoses with worm gear
clamps appeared to be routed
between each pump and the wet
well within the enclosure, which
could present an opportunity for
H2S gas to exit the wet well through
a potential loose or cracked hose.
▪ An office Uninterruptible Power
Supply (UPS) was observed within
the pump/electrical equipment
enclosure, not in an electrical
enclosure.
▪ One light fixture was observed
inside the pump/electrical
enclosure. No exterior lighting was
observed.
▪ No intrusion switches were
observed on site.
▪ No lift station discharge flowmeter
was observed.
▪ The City advised they plan to
abandon this lift station within a
year.

Climate Control Vulnerability Condition Photo(s)
Flooding
▪ Site grade is crushed rock.

Fair to
Good

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 76 OCTOBER 2025
- Wet well top slab extends
approximately 6 inches above
grade preventing flooding.

Electrical Outages
▪ No standby power generator or
portable generator connection was
observed.

Extreme Heat
▪ An air supply fan and an exhaust
vent were not observed inside the
electrical control panel.

3.4.4 Hydraulic Assessment
The Countryside Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 2.0 times per hour on average with a maximum of 11 starts per hour. Pump #2 starts approximately 1.7 times per hour on average with a maximum of 16 starts per hour. Both pumps have a similar number of starts per hour and would wear evenly. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 15 HP, 4-pole (1750 rpm) motor should have a maximum number of 10.7 motor starts per hour. It was observed that the instances number of starts per hour exceeds the NEMA recommended starts per hour based on the provided SCADA data. This indicates that the existing operational set points may need to be adjusted. Note that newer motor models are capable of exceeding NEMA’s recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 230 minutes of run time per day (3,510 total hours) while pump #2 averages approximately 194 minutes of run time per day (2,957 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Countryside Lift Station force main is a 6” HDPE and PVC pipe installed in 2002. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC and HDPE is approximately 50 years. Countryside Lift station is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the flow velocity through this existing 6” force main is estimated at approximately 6.2 ft/sec which is in accordance with HI standards.

3.4.5 Recommended Improvements
Since Countryside Lift Station is currently being decommissioned, there are no recommendations for this site.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 77 OCTOBER 2025

3.5 Legacy Lift Station

3.5.1 Location and Layout
The Legacy Lift Station is located on Valor Lane between Farmsworth Lane and Rubert Franks Drive within a small, fenced site. This site can be accessed by a chain-link gate on the south side of Valor Lane. There is plenty of parking on the street, however, traffic control must be implemented to access the wet well located in the middle of Valor Lane. The lift station is a submersible duplex station with lift up fiberglass valve enclosure and wet well located within Valor Lane. The Legacy Lift Station pumps flows from the southern half of the Countryside residential community to the northern half of the community where it flows by gravity to the Countryside Lift Station.

3.5.2 System Characteristics
Dudek performed a comprehensive lift station condition assessment at Lift Station No. 3. The following bullet points contain observations made during the February 12, 2025, site inspection and information provided by the City during the pre- and post-inspection workshops.

3.5.2.1 Pump Station
A summary of the pumping units for Legacy LS is provided on Table 20, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 21.

Figure 92: Legacy Lift Station Location
Figure 93: Legacy Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 78 OCTOBER 2025
Table 20. Legacy Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Vaughan SE3F1 Unknown
Pump Type Chopper Submersible Non-Clog Submersible
Design Capacity 250 gpm @ 20’ TDH
Motor, hp 5
Motor Operation Constant Speed
Speed, rpm 1750
Discharge Diameter, inches 4
Year Installed 2006, Pump #1 Replaced in 2011
Table 21. Legacy Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete
Diameter, feet 6
Depth, feet 17.5
Floor Elevation, feet -43.5
Influent Sewer Invert, feet -38.34
Cover/Hatch Type 3’x5’ double leaf hatch
Bypass Assembly
Valve Location Within fiberglass enclosure
Bypass Connection None
Force Main
Diameter, inches 6”
Length, feet 2006
Material PVC

3.5.2.2 Operations and Maintenance History
Records indicate that Pump #1 and electrical panels were replaced in 2011. Operations staff informed that the pumps were scheduled to be replaced again within two weeks of the February 2025 inspection. No ragging issues reported at this lift station. It was observed that the suction piping within the wet well was repaired at some point.

Operations also informed that one of the swing arm check valves were replaced approximately 3 years ago with a disc check valve.

3.5.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at Legacy Lift Station. Table 22 contains observations made during the February 11, 2025 site inspection and information provided by the City during the pre- and post-inspection workshops. During the April 8, 2025 post inspection workshop, the City indicated that the

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 79 OCTOBER 2025
Legacy Lift Station will be abandoned by 2030. Flows previously served by this lift station will be redirected via gravity to the new Southern Lift Station which will replace this lift station.

Table 22. Legacy Lift Station Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ No onsite water service.
▪ Site grading is dirt and sloped towards
above grade fiberglass enclosure.
▪ The only lighting observed onsite was
within the fiberglass enclosure.
▪ Fiberglass enclosure was unlocked at the
time of the inspection with no intrusion
switch.
- Site perimeter fence was locked at the
time of the inspection.
▪ No permanent/integrated fall protection at
wet well access hatch.

Fair
Figure 94: Legacy Lift Station Facility Site
Mechanical Condition Photo(s)
Pumps
▪ Submersible pumps were not pulled for
assessment during field inspections.
▪ Mild corrosion observed at pump guide rail.
- Guide rails appear to have a kink in
them near the top. Corrosion at the
pump guide rail supports may be the
cause.

Good
Figure 95: Legacy Lift Station Submersible Pumps and
Guide Rails

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 80 OCTOBER 2025
Piping and Valves
▪ Varying levels of mild corrosion observed at
discharge piping and valves. Piping and
valves are in good condition.
- Check valve observed to have a leak
causing accelerated corrosion and
coating failure.
- Significant dirt and debris within the
fiberglass enclosure.
▪ Air valve within fiberglass enclosure is
damaged and was disconnected at the
time of the inspection.

Good
Figure 96: Legacy Lift Station Piping and Valves
Structural Condition Photo(s)
Wet Well
▪ Wet well access hatches were observed to
be in poor condition.
- Lift assist is corroded and no longer
working.
- Severe corrosion observed at pump
hatch frame.
- Operations informed that the access
hatch has to be bolted shut to reduce
noise of traffic driving over it.
▪ The wet well liner was observed to be in
good condition.
- Suction pipe penetrations have been
repaired with grout and are not
protected by the liner.
- Liner failing around influent wet well
penetration.
▪ Mild root intrusion observed at the wet well
inlet piping penetration.
▪ Grease solids accumulation is occurring at
the wet well high-water line.

Fair
Figure 97: Legacy Lift Station Wet Well Access and Root Intrusion

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 81 OCTOBER 2025
Figure 98: Legacy Lift Station Grease Accumulation in
Wet Well
Electrical & Instrumentation Condition Photo(s)
▪ Pump Control Panel, level transmitter, and
Mission Communications Cellular Wireless
RTU appeared new and are located on a
rack on site away from the existing green
equipment fiberglass enclosure.
▪ City staff advised Pump Control Panel, level
transmitter, and RTU were recently
installed and the old control panel,
transmitter, and RTU were removed from
within the green enclosure.
▪ City staff advised that the conduits
between the wet well and the green
enclosure were intercepted underground
and routed to a new junction box adjacent
to the green enclosure. New conduits run
from the j-box to the new control panel
rack. Dudek observed only one conduit of
the approximate size of the conduits in the
wet well entering the new j-box. Dudek
assumes the second conduit still routes
into the green equipment enclosure.
▪ No sealing fittings were observed on any
conduits on site and are required per the
National Electrical Code and California
Electrical Code on conduits once they leave
a hazardous area, such as the wet well. A
lack of sealing fittings is a safety hazard, a
risk for equipment damage, and can allow
H2S gas to enter the electrical equipment.

The spray foam sealing conduits in the new
control panel is not sufficient and does not
meet code for a hazardous barrier.
▪ City staff indicated that the pumps start
and stop based on signals from the level
transmitter.

Good
Figure 99: Legacy Lift Station New Pump
Control Panel Rack
Figure 100: Legacy Lift Station New Junction Box
Intercepting Wet Well Conduits

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 82 OCTOBER 2025
▪ Lift Station I/O appeared to be transmitted
off site using a Mission Communications
Cellular Wireless RTU.
▪ An air supply fan and an exhaust vent were
observed inside the pump/electrical
enclosure.
▪ One light fixture was observed inside the
pump/electrical enclosure and staff stated
it is active. No exterior lighting was
observed.
▪ Existing electrical service was observed to
be 240-volts, three-phase.
▪ No arc flash stickers were observed on the
electrical equipment.
▪ No standby power generator or portable
generator connection was observed.
▪ An existing transformer and 120V/240V
single-phase panelboard was observed
under the pump/electrical enclosure and
staff stated it is active.
▪ No intrusion switches were observed on
site.
▪ No lift station discharge flowmeter was
observed.
▪ The existing level transducer appeared to
be hanging from its cable in the wet well,
which can cause premature failure of the
cable.

Figure 101: Legacy Lift Station Missing Sealing Fittings on Conduits from Wet Well
Figure 102: Legacy Lift Station Existing Level Transducer Hanging from its Cable
Climate Control Vulnerability Condition Photo(s)
Flooding
▪ Site grading is dirt and sloped towards
above grade fiberglass enclosure.

Electrical Outages
No standby power generator or portable
generator connection was observed.

Extreme Heat
▪ An air supply fan and an exhaust vent were
not observed inside the electrical control
panel.

Good

3.5.4 Hydraulic Assessment
The Legacy Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 2.7 times per hour on average with a maximum

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 83 OCTOBER 2025
of 13 starts per hour. Pump #2 starts approximately 0.01 times per hour on average with a maximum of 7 starts per hour. This indicates that the existing operational set points may need to be adjusted. Dudek recommends for the City Operations staff to investigate the cause of this discrepancy. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 5 HP, 4-pole (1750 rpm) motor should have a maximum number of 16.3 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed that both pumps are in compliance with the number of NEMA recommended starts per hour.

Pump #1 averages 245 minutes of run time per day (3,738 total hours) while Pump #2 averages approximately 0.2 minutes of run time per day (3.3 total hours). This data indicates that the Pump #1 runs significantly more than pump #2. Dudek recommends for Operations staff to determine why such a large discrepancy between run time of pumps is taking place.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Legacy Lift Station force main is a 6” PVC pipe installed in 2006. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. Legacy Lift station is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the flow velocity through this existing 6” force main is estimated at approximately 2.8 ft/sec which is in accordance with HI standards.

3.5.5 Recommended Improvements
Recommended improvements were developed for Legacy LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 23.

Table 23. Legacy Lift Station Recommended Improvements
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project
(Term)
EI&C Install sealing
fittings
Install conduit sealing fittings on all
conduits as they exit the hazardous
envelope the wet well) and before
they enter any enclosures or
junction boxes per NEC. This could
be done before entering the new jbox and just as the conduit(s) enter the green fiberglass equipment
enclosure.

Code
Violation/
Operational
Failure
Maintenance
EI&C
Perform Power
System Study &
Install Arc Flash
Stickers
Per NFPA 70E, a power system
study should be performed, and
updated every 5 years Updates
should be made whenever
modifications are made. Arc flash
Safety Risk
Arc Flash /
Short Circuit
Study
Program
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 84 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project
(Term)
stickers should be provided on the
electrical equipment.

EI&C/
Climate
Control
Vulnerability
Install a
Portable
Generator
Connector and
Transfer Switch
This will allow the City to bring a
portable generator on site to
provide power when utility power
fail.

Operational
Failure
Power and
Generator
Program
(Near-term)
EI&C Install Intrusion
Switches
Intrusion switches are not currently
installed on the electrical
equipment. It is recommended to
install intrusion switches for RTU
notification to prevent unauthorized
access and tampering of lift station
equipment.

Safety Risk/
Security Risk Maintenance
EI&C
Install
Discharge Flow
Meter1
Install flowmeter on pump
discharge to allow flow monitoring
which provides useful operational
data and serves as an indication of
diminishing pump performance over
time.

Operations
Preference N/A
Mechanical
Recoat Existing
Mechanical
Equipment in
Dry Well1
The existing mechanical piping,
valves, and pumps within the
fiberglass enclosure remain in good
condition, however there is minor
corrosion and coating delamination
occurring in several locations
Coating
Delamination
/ Failure
Maintenance
Mechanical Replacement of
Pumps1
Submersible pumps were not pulled for
assessment during field inspections;
however it is assumed they are either
at or near the end of their useful life.

The existing pump guide rails appear to
have a kink in them near the top likely
due to corrosion.

Operational
Failure N/A
Mechanical Replace Air
Valve
Air valve within fiberglass enclosure is
damaged and was disconnected at the
time of the inspection.

Operational
Failure Maintenance
Mechanical
Install Lift
Station Bypass
Connection1
There is no existing bypass connection
for this lift station. It is recommended
to install a force main bypass
connection in the event of a lift station
failure.

Increased
SSO
Potential
N/A
Structural
Replace Wet
Well Access
Hatches
The existing wet well access
hatches and pump access hatches
are severely corroded and the lift
assist is no longer working. The
pump access hatch has to be bolted
down to reduce noise from traffic. It
is recommended to replace the
Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 85 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project
(Term)
access hatches with new hatches
that are equipped with integrated
fall protection, slam lock, and lift
assist.
(Near-term)
Structural
Wall
Penetration and
Wet Well Liner
Improvements1
Liner failing around influent wet well
penetration. Mild root intrusion
observed at the wet well inlet piping
penetration. Use hydrophilic grout at all
wall penetrations to prevent water
infiltration into the wet well.

Preventative
Maintenance N/A
Site Civil/
Climate
Control
Vulnerability
Install Crushed
Rock and
Regrade Site
Away from
Pump
Enclosure1
Grade is sloped towards above grade
pump enclosure which may cause
flooding during precipitation event.

Preventative
Maintenance Maintenance

1. This recommended improvement is assumed to not be required due to the planned decommission of the lift station within one year of writing this technical memorandum. If the lift station is in service beyond the currently scheduled decommission timeline, then it is recommended that the City perform this improvement.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 86 OCTOBER 2025

3.6 Alder Canal - Villa Ave Lift Station

3.6.1 Location and Layout
The Alder Canal – Villa Ave Lift Station is located just to the southeast of the intersection of Villa Lane and E Villa Road. The lift station is a full sized dry well / wet well lift station within a fenced facility. Site access is provided by a gate on the south side of East Villa Road. There is plenty of parking within the site perimeter fence.

Figure 103: Villa Lift Station Location

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 87 OCTOBER 2025
Figure 104: Villa Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 88 OCTOBER 2025

3.6.2 System Characteristics

3.6.2.1 Pump Station
A summary of the pumping units for Alder Canal – Villa Ave LS is provided on Table 24, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed.

Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 25.

Table 24. Alder Canal – Villa Ave Lift Station Pumping Units Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Pentair Hydromatic Pump, Model
80MMP
Pentair Hydromatic Pump, Model
80MMP
Pump Type Self Priming Dry Well Self Priming Dry Well
Design Capacity 1908 gpm @ 76.6’
Motor, hp 60
Motor Operation VFD
Speed, rpm 1780
Discharge Diameter, inches 10
Year Installed 2005, Rehabilitation Date Unknown
Table 25. Alder Canal – Villa Ave Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Cast in place concrete
Diameter, feet 16’-4” x 27’
Depth, feet 32
Floor Elevation, feet -49.29
Influent Sewer Invert, feet -66.87
Cover/Hatch Type 30”
Dry Well
Size, feet Unknown
Material Cast in place concrete
Depth, feet 19
Cover/Hatch Type 8’ x 10’ Access Hatch with Staircase; 30” x 36” Access Hatch with Ladder Bypass Assembly
Valve Location Within dry well
Bypass Connection None
Force Main
Diameter, inches 20
Length, feet 12,236
Material PVC

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 89 OCTOBER 2025

3.6.2.2 Operations and Maintenance History
Villa Lift Station was built in 2005. The lift station was rehabilitated at some point and a new dry well access stair and hatch were installed. Operations informed that the dry well is entered every six months to perform pump and valve maintenance. Operations staff also indicated that there have never been any flooding issues withing the dry well. Magnesium Oxide and Commander treatments are added to the wet well to combat odor issues and hydrogen sulfide. Previously the odor control treatments were added to the influent manhole.

Operations staff reported low flows at this site. In order to flush the force main, the City fills the wet well with canal water and conducts a flushing cycle every three months.

3.6.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at Villa Ave Lift Station. Table 26 contains observations made during the February 12, 2025 site inspection and information provided by the City during the pre- and post-inspection workshops.

Table 26. Alder Canal - Villa Ave Lift Station Inspection Summary Site Civil/ Safety & Security Condition Photo(s)
General
▪ Entrance to the Alder Canal – Villa Ave
Lift Station site is through an asphalt
concrete access road off of E Villa Rd
▪ There is an existing double leaf chain
link entrance gate for vehicular access
to the site
▪ An existing chain link fence with barbed
wire surrounds the site to prevent
unauthorized access
▪ The existing asphalt concrete pavement
was observed to have some large
cracks, however the AC pavement
remains in fair condition
▪ Outside of the AC pavement the site
grading is unpaved and becomes muddy
during precipitation events
▪ Dry well access stairs are severely
corroded which is a safety risk to anyone
entering/ leaving the dry well. Appears to
be caused by infiltration at air duct
penetration
▪ Tripping hazards observed at grade
around wet well access cover (junction
box hatch, level sensor access flange,
chemical injection hose)
Excellent
Figure 105: Villa Lift Station Facility Access Road and Entrance Gate
Figure 106: Villa Lift Station Site Security Fencing
and AC Pavement

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 90 OCTOBER 2025
▪ The chemical feed hose for the
Magnesium Oxide is laid out on the top
slab of the wet well and wrapped around
the wet well access cover posing a
tripping hazard.
▪ Infiltration was observed at several wall
penetrations throughout dry well.
- The infiltration on the wall adjacent
to the access stairs is most likely
caused by surface water that ponds
up in the depressed area next to the
top slab. During heavy rains, the
accumulation of water in this area is
most likely seeping down along the
exterior of the dry well structure and
infiltrating through the existing
conduit and duct wall penetrations.
- The depressed area also poses a
tripping hazard for operations staff
▪ Dry well light switch is located at the
bottom of the old access ladder.

Operations staff have to enter the dry
well in the dark which is a safety risk
▪ Per staff, not all of the lighting within the
dry well and electrical building is
operable and is inadequate
▪ Influent manhole lid is severely corroded
and fell into the manhole during the
inspection leaving a significant safety
risk for operations staff working in the
area
▪ No onsite water. Chemical storage on
site requires an eye wash station in case
of exposure to operations staff
- OSHA 29 CFR 1910.151 requires eye
wash stations be located at facilities
with injurious corrosive materials
stored
▪ Gas sensors in the drywell were not
functioning at the time of the inspection.

This introduces a safety risk for
operations staff working in unsafe
conditions
▪ No locks or intrusion alarms at hatches
provides a public safety hazard
Figure 107: Villa Lift Station Dry Well Access Stairs
Figure 108: Villa Lift Station Above Grade Tripping Hazards Near Wet Well
Figure 109: Villa Lift Station Depressed Area Near
Dry Well Top Slab
Figure 110: Villa Lift Station Dry Well Light Switch

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 91 OCTOBER 2025
▪ The right door to the electrical service
entrance switchboard will not latch
closed and should be repaired. An open
door invites intruders, critters, and
rain/water to get into the switchboard,
which could affect operation
▪ A limit switch believed to be the flood
alarm was observed to be broken near
the dry well floor
▪ Emergency lighting fixtures appeared
corroded in drywell
▪ Wet well access manhole is corroded
and poses risk to operations staff
walking around the area
▪ Influent manhole needs to be cleaned;
old chemical build-up on top of bench
and on walls
Figure 111: Villa Lift Station Inoperable Lighting
within Dry Well
Figure 112: Villa Lift Station Inoperable Lighting within Electrical Building
Figure 113: Villa Lift Station Influent Manhole Lid at the Bottom of Manhole

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 92 OCTOBER 2025
Mechanical Condition
Pumps
▪ Skid mount packaged duplex dry pit
submersible pumps are located within
the dry well
▪ Pumps are anchored into to concrete
equipment pad. The pump motors are
mounted to a metal frame that is
anchored to the concrete pad.
- The pump bases are in fair condition
and are adequately anchored. The
pump bases are showing signs of
minor corrosion and oxidation
- The metal motor mount frames are
experiencing minor to moderate
levels of corrosion and are showing
signs of oxidation
▪ Insignificant extent of minor corrosion
and coating delamination was observed
on the pumping units
▪ All flanged connections appear secure
with no signs of leaking
▪ Dry well contains suction isolation valve
and piping stub outs for two (2) future
pumps.
▪ The bearing bracket surrounding the
pump shaft was replaced for one of the
pumping units, leaving the v-belt drive
exposed. Both of these assets appear to
be in good condition
- The other pumping unit appears to
include the original bearing bracket
and the v-belt drive is within an
enclosure.
- These assets appear to be in fair
condition with minor levels of
corrosion and oxidation and varying
levels of coating delamination
▪ The pump suction body and suction
elbow for both pumping units were
observed to be in fair condition with
minor levels of corrosion and oxidation
occurring
▪ One (1) submersible sump pump is
located within the sump pit within the
dry well.
- The submersible sump pump was not
pulled for assessment during field
inspections, however it was observed
Fair
Figure 114: Villa Lift Station Dry Pit Pumping Units and Discharge Piping
Figure 115: Villa Lift Station Dry Pit Pumping Units and Force Main
Figure 116: Villa Lift Station Future Pump
Connection Stub Outs
Figure 117: Villa Lift Station Dry Pit Pump Motor
Shaft and V-Belt Drive

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 93 OCTOBER 2025
that the sump pump was
experiencing moderate to severe
levels of corrosion
- Unable to determine if sump pump
discharge line elevation is above wet
well water level
- If plastic check valve on sump pump
discharge line fails, wet well may
drain back into the dry well
- Infiltration observed at wall
penetration of sump pump discharge
line
▪ Operations have to use truck crane to
remove pumps from dry well. No
permanent bridge crane within dry well.

Figure 118: Villa Lift Station Pump Suction Body and Suction Elbow
Piping and Valves
▪ The existing pump suction, pump
discharge, and force main piping and
valves are in good condition with little to
no corrosion observed
▪ The existing floor-mounted pipe supports
for the pump suction piping are in fair
condition with minor signs of corrosion
and oxidation occurring
▪ The existing wall-mounted pipe supports
appeared to be in good condition with
secure anchorage and no corrosion
observed
▪ The sump pump piping, valves and
fittings are in good condition
▪ The suction piping within the wet well
are in poor to fair condition
- Varying levels of corrosion, loss of
material thickness, and coating
delamination were observed on the
metal piping and fittings
▪ The PVC piping and fittings were in
better condition
▪ There is no force main bypass
connection at this lift station
▪ No flow meter present at lift station
Fair
Figure 119: Villa Lift Station Pump Discharge
Piping and Valves
Figure 120: Villa Lift Station Pump Discharge Piping,
Valves, and Force Main

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 94 OCTOBER 2025
Figure 121: Villa Lift Station Floor-Mounted Pipe Supports Figure 122: Villa Lift Station Wall-Mounted Pipe Struts Figure 123: Villa Lift Station Sump Pump Discharge Piping Figure 124: Villa Lift Station Wet Well Suction Piping

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 95 OCTOBER 2025
Odor Control/Ventilation
▪ Ventilation ducts within the dry well are
primarily in good to excellent condition,
however some locations were observed
to have minor corrosion occurring on the
ducting
▪ The air exhaust blowers were observed
to be in good condition
▪ Little to no corrosion observed on
ventilation supply fans
▪ Minor corrosion and oxidation observed
on the inlet forced air ventilation system
filter banks
▪ The electrical building heater and
exhaust units and vents were observed
to be in good condition
▪ Magnesium Oxide chemical dosing
system discharges into the wet well.
- Extensive chemical splattering and
spillage observed around the
Magnesium Oxide storage container.

Good
Figure 125: Villa Lift Station Dry Well Supply Air Ducting Figure 126: Villa Lift Station Dry Well Ventilation Ducting Figure 127: Villa Lift Station Ventilation Air Exhaust Blowers Figure 128: Villa Lift Station Air Intake Filter Bank and Supply Blower Motors

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 96 OCTOBER 2025
Figure 130: Villa Lift Station Electrical Building Heater and Exhaust Vents
Structural Condition Photo(s)
Dry Well
▪ The dry well access ladder is in good
condition with little to no corrosion
observed and secure anchorage to the
walls
▪ Infiltration was observed at several wall
penetrations throughout dry well
- The infiltration on the wall adjacent
to the access stairs is most likely
caused by surface water that ponds
up in the depressed area next to the
top slab. During heavy rains, the
accumulation of water in this area is
most likely seeping down along the
exterior of the dry well structure and
infiltrating through the existing
conduit and duct wall penetrations.

Fair to
Good
Figure 131: Villa Lift Station Dry Well Access Ladder
Figure 129: Villa Lift Station Electrical Building
Heater and Exhaust Units

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 97 OCTOBER 2025
- Infiltration was also observed at the
penetration for the sump pump
discharge piping
▪ Dry well access stairs are severely
corroded which is a safety risk to anyone
entering/ leaving the dry well. Appears to
be caused by water infiltration at air duct
penetration
▪ In general the existing wall penetrations
within the dry well are properly sealed
and in good condition, however some
penetrations were observed to have
water intrusion.
▪ The dry well pumps are
removed/replaced through the dry well
roof equipment hatches. No issues were
observed with the equipment hatches
Figure 132: Villa Lift Station Infiltration
Marks within Dry Well
Figure 133: Villa Lift Station Dry Well Access Stairs
Figure 134: Villa Lift Station Pipe Penetration
within Dry Well

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 98 OCTOBER 2025
Figure 135: Villa Lift Station Dry Well Roof Equipment Hatch Wet Well
▪ The existing wet well is a below grade
concrete structure with a PVC T-Lok liner
that remains in good condition with no
holes or openings observed
▪ The underlying concrete was properly
protected from the PVC liner and
therefore was not inspected
▪ There appeared to be some
discoloration of the liner and signs of
chemical buildup within the bottom of
the wet well
▪ The wall penetrations through the wet
well wall appeared to be properly sealed
▪ The wet well ceiling/top slab was
observed to be in fair to good condition
▪ The PVC liner had some discoloration
around the opening for the ultrasonic
level transducer and the access
manhole opening
▪ Moderate to severe corrosion of the
concrete was observed above the liner
termination within the wet well access
opening
▪ Moderate corrosion of the access
manhole frame

Good
Figure 136: Villa Lift Station Wet Well Structure
(Facing East)
Figure 137: Villa Lift Station Wet Well Structure
(Facing West)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 99 OCTOBER 2025

Figure 138: Villa Lift Station Wet Well Ceiling/Top Slab (Facing East)
Figure 139: Villa Lift Station Wet Well Ceiling/Top Slab (Facing West)
Figure 140: Villa Lift Station Wet Well Bottom and
Suction Piping
Figure 141: Villa Lift Station Wet well Access
Cover and Frame

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 100 OCTOBER 2025
Lift Station Influent Manhole
▪ The existing lift station influent manhole
is coated with a PVC T-Lok liner that
remains in fair condition with minor
signs of degradation and flaking.
▪ At the bottom of the influent manhole
there is an accumulation of chemical
buildup on the manhole bench and in
the channel.
▪ The manhole access cover and frame
are severely corroded with visible loss of
material thickness and structural
integrity
- During the field inspection, the
manhole cover fell through the frame
into the manhole.

Fair
Figure 143: Villa Lift Station Influent Manhole Bench and Chemical Buildup
Figure 144: Villa Lift Station Influent Manhole Bench
and Chemical Buildup

Figure 145: Villa Lift Station Manhole
Frame and Cover
Figure 142: Villa Lift Station Influent Manhole
Cone Section and Liner

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 101 OCTOBER 2025
Electrical Building
▪ The existing prefabricated electrical
building is in good to excellent condition
Good to
Excellent
Figure 146: Villa Lift Station Electrical Building
Electrical & Instrumentation Condition Photo(s)
Electrical Building
▪ The exterior of MCC in the Electrical
Building appeared to be in good
condition and had 15 years of useful life
remaining.
▪ There are four holes in the front of the
Pump #1 MCC section that need to be
covered—the holes appeared to be from
previous pilot lights, pushbuttons, or
switches.
▪ City staff reported that they have
replaced one of the two VFDs in the MCC
with soft starters when the VFD failed
and will replace the second VFD with a
soft starter when it fail. However, it
appeared that the keypads for both
pumps indicate that they are already
both run by soft starters.
▪ Corrosion from H2S gas was reported by
staff in the MCC and other electrical
equipment. Staff stated that the
corrosion was less at Villa LS compared
to Lift Station No. 3.

Good

Figure 147: Villa Lift Station MCC Condition and Four
Holes in MCC Face for Pump #1
Figure 148: Villa Lift Station Partially Inoperable Lighting in Electrical Building

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 102 OCTOBER 2025
▪ No sealing fittings were observed on any
conduits on site except two conduits on
the wet well deck that terminate in a
stainless steel junction box for the level
sensor. Sealing fittings and are required
per the National Electrical Code and
California Electrical Code on conduits
once they leave a hazardous area, such
as the wet well. A lack of sealing fittings
is a safety hazard, a risk for equipment
damage, and is likely the reason for H2S
gas entering the Electrical Building.

Foam sealant was observed on the
conduits entering the control panel
through the floor in the electrical
building, but this method is not in
accordance with the NEC, as it does not
substitute for a sealing fitting.
▪ Some of the lighting inside the electrical
building appeared inoperable and needs
to be repaired or replaced.
▪ One exterior light on the electrical
building appeared to have been
replaced with an LED fixture. The three
remaining fixtures appeared to be
original fixtures from when the site was
built. The newer light appeared to be in
good condition.
▪ No arc flash stickers were observed in
the electrical building, or anywhere on
site.
▪ No third-party maintenance/testing
stickers were observed on the electrical
equipment.
▪ City staff indicated that the pumps start
and stop based on contacts from the
ultrasonic level transmitter, and that
there is no backup pump control using
float switches.
▪ The existing site PLC is an Allen-Bradley
Micrologix 1500, which was
discontinued in 2017 according to the
manufacturer’s web site. New parts are
no longer available.
▪ I/O is transmitted off site using a
Mission Communications Cellular
Wireless RTU, for the lift station.
▪ Per City staff, the wet well high level
signal is transmitted off site via separate
land phone line.

Figure 149: Villa Lift Station Existing Discontinued PLC

Figure 150: Villa Lift Station Level Transmitter
Junction Box (Left), Float Switch Junction Box (Right)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 103 OCTOBER 2025

Outdoors
▪ The stainless-steel junction box next to
the level transmitter mounting flange is
corroding, and since there is no sealing
fitting between it and the level sensor
flange, the junction box did not appear
to be rated for use in a hazardous
location but should be.
▪ The existing level transducer appeared
to be hanging from its cable in the wet
well, which can cause premature failure
of the cable.
▪ There appeared to be a stainless steel
enclosure embedded into the wet well
concrete deck, with its back removed to
allow what appeared to be a float switch
cable to go down into the wet well.

There was a conduit that emerges from
within the concrete deck that did not
appear to have a sealing fitting on it.

The Kellems grip on the cable appeared
to be heavily corroded. The enclosure is
not NEMA 7 rated for hazardous
locations and its door did not appear to
seal, so H2S gas could escape from it.
▪ All outdoor flex conduits appeared brittle
and damaged by the sun and elements.
▪ The existing chemical odor control
equipment located on the wet well deck
appeared to be powered by extension
cords from site convenience
receptacles. The City advised that they
are installing permanent power to the
equipment in the short-term future.
▪ The Site SES main switchboard door did
not close/latch properly, which can allow
dirt, vermin, water, and intruders inside.
▪ The Site SES main switchboard had a lot
of dust, dirt and cobwebs inside.
▪ Site SES main switchboard enclosure
exterior has surface rust.
▪ A portable generator receptacle was
observed. It allows a generator to be
brought on site to provide power during
a utility outage.

Fair

Figure 151: Villa Lift Station SES Main
Switchboard Condition
Figure 152: Villa Lift Station Corroded Exhaust
Fans Conduit (Left)
Figure 153: Villa Lift Station Drywell Conduit, Lighting and Instrument Corrosion

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 104 OCTOBER 2025
▪ The conduit that powers exhaust fans
EF-1 & EF-2 appeared to be heavily
corroded as it comes above grade and
does not have the protective 20 mil PVC
based corrosion protection tape around
it. The conduit appeared to be corroded
all the way through (left conduit in
photo).
▪ No lift station discharge flowmeter was
observed.
▪ City staff stated that the intrusion
switches on the hatches do not work and
do not report to the PLC.

Drywell
▪ City staff advised that the lighting in the
drywell is bad—not all of it works.
▪ City staff advised that the light switch is
in a bad spot—it is at the bottom of the
manway ladder. Staff would like the
light switch moved to the entry hatch
above.
▪ City staff advised that they don’t know if
the drywell flooded float switch works or
if it reports to the RTU or PLC.
▪ All conduit in the drywell appeared to be
galvanized rigid metal conduit, not PVCCoated galvanized rigid metal conduit.

There are areas in the drywell with
significant conduit corrosion due to
water infiltration
▪ A severely corroded instrument and
emergency light were also observed.

The Emergency light did not appear to
be operable.
▪ Drywell conduit and electrical/lighting
corrosion appeared to be all along the
wall closest to the electrical building
(north wall), and on the wall near the
drywell sump (south wall).
▪ Staff did not indicate an issue with the
gas detector in the drywell, but
information was not observed on its
display.

Wet Well

Fair

Not
Observed
Figure 154: Villa Lift Station Water Infiltration (Severe Conduit Corrosion Where Conduits Penetrate Wall)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 105 OCTOBER 2025
Climate Control Vulnerability Condition Photo(s)
Flooding
▪ The existing asphalt concrete pavement
was observed to have some large
cracks, however the AC pavement
remains in fair condition
▪ Outside of the AC pavement the site
grading is unpaved and becomes muddy
during precipitation events
Electrical Outages
▪ A portable generator receptacle was
observed. It allows a generator to be
brought on site to provide power during
a utility outage.

Extreme Heat
▪ Air cooling / temperature control was
observed within the electrical building.

Good to
Fair

3.6.4 Hydraulic Assessment
The Alder Canal – Villa Avenue Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 1.1 times per hour on average with a maximum of 16 starts per hour. Pump #2 starts approximately 1.3 times per hour on average with a maximum of 14 starts per hour. Both pumps have a similar number of starts per hour and would wear evenly. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 50 HP, 4-pole (1780 rpm) motor should have a maximum number of 6.8 motor starts per hour. . It was observed that the instances number of starts per hour exceeds the NEMA recommended starts per hour based on the provided SCADA data.

This indicates that the existing operational set points may need to be adjusted. Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 37.8 minutes of run time per day (576 total hours) while pump #2 averages approximately 55.6 minutes of run time per day (848 total hours). This data indicates that the pump #1 runs significantly more than pump #2. Dudek recommends for Operations staff to determine why such a large discrepancy between run time of pumps is taking place.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 106 OCTOBER 2025
The existing Villa Lift Station force main is a 20” PVC pipe installed in 2005. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. From the SCADA data that was received, the minimum flow and resulting velocity is 1,270 gpm and 1.3 ft/s.

Villa Lift station is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the maximum flow and resulting velocity is 2,350 gpm and 2.6 ft/s.

3.6.4.1 Lift Station and Force Main Capacity Issues
Per discussions with City staff, it is understood that this lift station was originally sized to handle an expected significant increase in sewer load based on future planned developments. The City explained that these developments are no longer expected to be completed resulting in the existing force main to be oversized in comparison to the flow capacity of the lift station. This has resulted in the sewage within the force main to turn septic due to the inability for the lift station to consistently fully flush the force main.

Legacy LS, Countryside LS, 4th & Wake LS are to be eliminated in the near future and flow from each will be redirected to the new Southern Lift Station. Once the 3 existing lift stations have been decommissioned, the Southern Lift Station will then pump towards the Alder Canal – Villa Avenue Lift Station (Alder Canal - Villa Ave LS).

Dudek evaluated rerouting the influent flow at the East Side LS directly east to the Alder Canal - Villa Ave trunk sewer. This option was found to be infeasible. Due to the minimal amount of fall between the East Side LS wet well’s influent gravity sewer and the Alder Canal - Villa Ave trunk sewer, redirecting flow via a new gravity sewer is not physically possible. Moreover, installing a new force main to redirect 100% of East Side LS’s flow to the Alder Canal - Villa Ave trunk sewer would increase the force main length, thus requiring the pump motors to be significantly upsized. This would then require upgrades to the electrical system and other infrastructure at East Side LS. Therefore, diverting flow from East Side LS to the Alder Canal - Villa Ave trunk sewer is not recommended.

3.6.5 Recommended Improvements
Recommended improvements were developed for Alder Canal – Villa Ave LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table

27. Table 27. Alder Canal - Villa Ave Lift Station Recommended Improvements Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
E&IC Install Sealing
Fittings
Install conduit sealing fittings
on all conduits as they exit the
hazardous envelope (including
the wet well).

Code
Violation/
Operational
Failure
Maintenance
EI&C
Perform Power
System Study
& Install Arc
Flash Stickers
Per NFPA 70E, a power system
study should be performed, and
updated every 5 years Updates
should be made whenever
modifications are made. Arc
flash stickers should be
Safety Risk
Arc Flash / Short
Circuit Study
Program
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 107 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
provided on the electrical
equipment.

EI&C
Perform ThirdParty Testing
on MCC and its
Breakers
This is preventative
maintenance that identifies
equipment issues ahead of
time. It also makes sure the
breakers are tripping at the
amperage and settings they are
supposed to—to keep staff and
equipment safe.

Injury Risk/
Operational
Failure
Testing and
Studies Program
(Near-term)
EI&C
Replace
Inoperable
Intrusion
Switches
It is recommended to install
intrusion switches for SCADA
notification to prevent
unauthorized access and
tampering of lift station
equipment.

Safety Risk/
Security Risk Maintenance
EI&C
Verify Existing
Drywell Flood
Alarm Device
Works and
Reports to RTU
To report drywell flood to staff
via RTU so they know before it
gets worse and can respond.

Operational
Failure Maintenance
EI&C Replace
Existing PLC
SCADA equipment is provided
with an Allen-Bradley MicroLogix
PLC which is at the end of its
useful life, as it was
discontinued in 2017 by the
manufacturer.

End of Useful
Life
Instrumentation
and Control
Program –
Phase 2
(Mid-term)
EI&C
Cap Holes in
MCC at Pump
#1
Code and safety issue. Code
Violation Maintenance
EI&C
Re-Design and
Install All New
LED Lighting in
Drywell
Per City Staff, lighting levels are
low in the drywell, and the light
switches are in bad locations
that require staff to enter the
dark drywell to access the light
switch at the bottom.

Safety Risk
Alder Canal –
Villa Lift Station
Rehabilitation
(Long-term)
EI&C
Replace
Damaged/
Corroded
Items in
Drywell
Replace corroded and damaged
conduits, lighting, and
equipment.

Operational
Failure Maintenance
EI&C
Clean, Repair,
and Paint the
Exterior of the
SES Main
Switchboard
Clean to reduce risk of
operational failure. Repair to
keep dirt, weather, vermin, and
intruders out. Repair and
repaint enclosure.

Preventative
Maintenance Maintenance
EI&C
Test all
Emergency
Lighting
The emergency lighting
appeared to be original
equipment. Recommend testing
Injury Risk/
Operational
Failure
Maintenance

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 108 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
and repairing/replacing any
failed equipment.

EI&C
Add Outdoor
Lighting at
Chemical Area
Would allow staff to work at and
troubleshoot the chemical
system when it is dark outside.

Operations
Preference
Alder Canal –
Villa Lift Station
Rehabilitation
(Long-term)
EI&C
Replace
Exterior Lights
on Electrical
Building
Would provide better lighting for
staff. Much more energy
efficient than existing.

Risk of Injury
Alder Canal –
Villa Lift Station
Rehabilitation
(Long-term)
EI&C
Repair or
Replace
Interior Lights
in Electrical
Building
No ensure bright enough
working space for staff.

Underlit electrical rooms are a
safety concern.

Operations
Preference
Alder Canal –
Villa Lift Station
Rehabilitation
(Long-term)
EI&C
Install
Discharge Flow
Meter
Install flowmeter on pump
discharge to allow flow
monitoring which provides
useful operational data and
serves as an indication of
diminishing pump performance
over time.

Operations
Preference
Alder Canal –
Villa Lift Station
Rehabilitation
(Long-term)
Site Civil/
EI&C
Replace Gas
Detection
System
The gas sensor in the dry well was
not functioning at the time of the
inspection.

Code
Violation/
Operational
Failure
Maintenance
Site Civil
Repair /
Replace Dry
Well Access
Stairs
Dry well access stairs are severely
corroded which is a safety risk to
anyone entering/leaving the dry
well.

Injury Risk/
Operational
Failure
Structures,
Hatches / Doors
and Bypass
Connection
Program –
Phase 1
(Near-term)
Site Civil /
Climate
Change
Vulnerability
Site Grading
There is a low point in the
unpaved area adjacent to the
dry well top slab where surface
runoff ponds up. During heavy
rains, the accumulation of water
in this area is most likely
seeping down along the exterior
of the dry well structure and
infiltrating through the existing
conduit and duct wall
penetrations. The depressed
area also poses a tripping
hazard for operations staff.

Preventative
Maintenance
Structures,
Hatches / Doors
and Bypass
Connection
Program –
Phase 1
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 109 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Site Civil
Mitigation of
Tripping
Hazards
Alleviate all tripping hazards
observed at grade around wet well
access cover.

Risk of Injury Maintenance
Site Civil Clean Influent
Manhole
At the bottom of the influent
manhole there is an accumulation
of residual chemical buildup on the
manhole bench and in the channel
Preventative
Maintenance Maintenance
Site Civil
Install
Permanent
Injection Port
for Magnesium
Oxide
Existing configuration on the wet
well top slab of the Magnesium
Oxide dosing hose poses a tripping
hazard around the wet well access
cover.

Risk of Injury
Pumps, Piping,
Supports and
HVAC Program
(Mid-term)
Site Civil/
Mechanical
Installation of
Emergency Eye
Wash and OnSite Water
Connection1
This facility has no onsite water
and no emergency eye wash
station. Chemical storage on site
requires an eye wash station in
case of exposure to operations
staff.

Risk of Injury N/A1
Mechanical
Recoat
Existing
Mechanical
Equipment in
Dry Well
The existing mechanical piping,
valves, and pumps within the dry
well remain in good condition,
however there is minor corrosion
and coating delamination occurring
in several locations
Coating
Delamination
/ Failure
Maintenance
Mechanical Routine Pump
Testing
It is recommended that the City
consider implementing routine
pump performance testing to
gather data on pump performance
and to prioritize preventive
maintenance activities. Routine
pump efficiency evaluations
provide valuable information on
trending of the facilities efficiency,
adequacy of installed equipment,
and electro-mechanical condition.

Since this data collection and
analysis has a cost associated with
it, routine pump performance
testing is only recommended for
pump stations that exhibit high
“load factors” (i.e., significant daily
runtimes), significant motor loads,
and/or high-head operations (e.g.,
two-stage pumping stations)
Preventative
Maintenance Maintenance
Mechanical Routine Valve
Exercising
It is recommended to adopt a more
frequent and proactive
Preventative
Maintenance Maintenance

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 110 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
maintenance schedule for valve
exercising.

Mechanical
Install Lift
Station Bypass
Connection
There is no existing bypass
connection for this lift station. It is
recommended to install a force
main bypass connection in the
event of a lift station failure.

Increased
SSO
Potential
Structures,
Hatches / Doors
and Bypass
Connection
Program –
Phase 1
(Near-term)
Mechanical
Replace
Existing Pump
Suction Piping
in Wet Well
The existing suction piping within
the wet well is experiencing
moderate to severe corrosion and
is likely at the end of its useful life.

Risk of Injury
Pumps, Piping,
Supports and
HVAC Program
(Mid-term)
Mechanical
Recoat
Existing Forced
Air Ventilation
Equipment
The existing above grade forced air
ventilation piping, fittings and
blowers are experiencing varying
levels of corrosion and coating
delamination
Preventative
Maintenance Maintenance
Mechanical
Clean
Chemical
Storage Area
Extensive chemical staining and
spattering around the Magnesium
Oxide storage tank. Chemical spills
need to be cleaned and disposed
of according to OSHA code.

Preventative
Maintenance Maintenance
Mechanical
Replace Force
Main with
Smaller
Diameter
Force Main
Existing force main is oversized
with no expectation of a future
significant increase in sewer
loading at the lift station. A smaller
diameter force main will help
improve flow velocity through force
main and reduce sewage retention
time within the pipeline.

Odor /
Operational
Issues
Force Main
Program –
Phase 2
(Mid-term)
Structural
Replacement
of Influent
Manhole
Access Cover
Influent manhole lid is severely
corroded and fell into the manhole
during the inspection leaving a
significant safety risk for
operations staff working in the
area
Risk of Injury
Structures,
Hatches / Doors
and Bypass
Connection
Program –
Phase 1
(Near-term)
Structural
Replace Wet
Well Access
Cover
Access to the existing wet well
is through a cast iron manhole
lid. It is recommended to
replace the cast iron access
cover with a new aluminum or
type 316 stainless steel hatch
that is equipped with integrated
fall protection, slam lock, and
lift assist. Alternatively, the
existing cast iron cover can be
Safety Risk/
Security Risk
Structures,
Hatches / Doors
and Bypass
Connection
Program –
Phase 1
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 111 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
removed and a new, lockable
composite manhole cover and
frame can be retrofitted in its
place.

Structural
Wall
Penetration
Improvements
Use hydrophilic grout at all wall
penetrations to prevent water
infiltration into the dry well. Preventative
Maintenance
Structures,
Hatches / Doors
and Bypass
Connection
Program –
Phase 2
(Near-term)
Structural
Rehabilitate
Liner
Termination
within Wet
Well
Rehabilitate the existing
concrete at the liner
terminations within the wet well
and provide improvements to
the liner terminations as-needed
to prevent accelerated corrosion
of the structure.

Operational
Failure
Structures,
Hatches / Doors
and Bypass
Connection
Program –
Phase 2
(Near-term)

1. Future recommendation to be completed once a potable waterline is installed in the vicinity of this facility.

3.7 3rd & Ross Lift Station

3.7.1 Location and Layout
The 3rd & Ross Lift Station is located north of West Ross Street, between 2nd street and 3rd street. This lift station can be accessed by a chain-link fence on the north side of West Ross Avenue. Parking can be found between the lift station and West Ross Avenue. The lift station is a self-priming duplex station with lift up fiberglass enclosure.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 112 OCTOBER 2025
Figure 155: 3rd & Ross Lift Station Location

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 113 OCTOBER 2025

3.7.2 System Characteristics

3.7.2.1 Pump Station
A summary of the pumping units for 3rd & Ross LS is provided on Table 28, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 29.

Table 28. 3rd & Ross Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Gorman Rupp Model T4A3-B Gorman Rupp Model T4A3-B Pump Type Self Priming Self Priming
Pump Mount Above grade
Design Capacity 325 gpm @ 27’ TDH
Motor, hp 7.5
Motor Operation Constant Speed
Speed, rpm 1450
Discharge Diameter, inches 4
Year Installed 1988; Pumps were replaced in 2016/2017
Figure 156: 3rd & Ross Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 114 OCTOBER 2025
Table 29. 3rd & Ross Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete
Diameter, feet 5.5
Depth, feet 19.2
Floor Elevation, feet -61.7
Influent Sewer Invert, feet -53.7
Cover/Hatch Type 24” Manhole
Bypass Assembly
Valve Location Above grade fiberglass enclosure
Bypass Connection None
Force Main
Diameter, inches 6”
Length, feet 224
Material HDPE

3.7.2.2 Operations and Maintenance History
The 3rd & Ross Lift Station’s pumps were replaced in 2016/2017. However, Operations informed that mechanical issues have since been experienced at this facility. Additionally, operations reported that the check valves have experienced ragging in the past, although they are currently considered acceptable by the City staff.

3.7.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at the 3rd & Ross Lift Station. Table 30 contains observations made during the February 12, 2025 site inspection and information provided by the City during the pre- and post-inspection workshops. During the lift station review workshop on August 5, 2025, the City reported that it had received quotes for rehabilitating the existing lift station wet well. Wet well rehabilitation is scheduled to begin in fiscal year (FY) 2025 and will be completed before this technical memorandum is finalized.

The work includes removing mechanical equipment, piping, and related components from the wet well, followed by concrete repair and liner installation. The City noted that this rehabilitation may extend the life of the facility by a few years before additional upgrades are needed in the mid- to long-term.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 115 OCTOBER 2025
Table 30. 3rd & Ross Lift Station Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ Site grade around the lift station is dirt.
- Low point observed at the edge of the
pad. Ponding water at low points and/or
high groundwater may accelerate
deterioration of the wet well.
▪ No onsite water service.
▪ No permanent/integrated fall protection at
wet well access cover.
- Wet well access cover is corroded and
introduces a safety risk to operations.
▪ Fiberglass enclosure was unlocked at the
time of the inspection with no intrusion
switch.
▪ No lighting observed on site.

Fair/Good
Figure 157: 3rd & Ross Lift Station Facility Site
Mechanical Condition Photo(s)
Pumps
▪ Self-priming pumps are in good condition.
- Minor corrosion and coating
delamination observed at flanges.
- No ragging reported at the site at the
time of the inspection.
▪ Pumps are belt driven. Belts are protected
by belt guards.
▪ Pumps are controlled by ultrasonic level
transmitter with float high water alarm.

Good
Figure 158: 3rd & Ross Lift Station Self-Priming
Pump and Motors
Piping and Valves
▪ Pump discharge piping (force main) within
wet well was observed to be severely
corroded and is experiencing significant
loss of pipe wall thickness. This section of
the force main is at high risk of failure.
▪ Mild to moderate corrosion and coating
delamination was observed on the above
grade suction and discharge piping.
▪ No bypass connection observed.

Poor
Figure 159: 3rd & Ross Lift Station Piping and Valves

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 116 OCTOBER 2025
Structural Condition Photo(s)
Wet Well
▪ Wet well concrete was observed to be
cracked and severely corroded. Majority of
the wet well structure’s interior has
appeared to have lost approximately 3” to
4” of concrete from the original surface
profile and sections of the exposed rebar
have corroded to the point that portions of
the rebar are missing. Wet well is in poor
condition.
▪ Wet well access manhole and rim were
observed to be moderately corroded
providing a safety risk for operations.
- Manhole cover is not a standard lid.
- Manhole ring is corroded and has
appeared to have disconnected from the
wet well top slab.
▪ There are no conduit seal offs installed on
conduits leaving the wet well, and there are
penetrations between the between the wet
well and the enclosure above that are not
sealed, causing the enclosure area to be
considered a Class 1 Div 1. Hazardous
area. Neither the motors or the electrical
and controls equipment within the
enclosure are rated for a Class 1, Division 1
hazardous location. H2S gas corrosion was
observed in the motor control panel.

Poor

Figure 160: 3rd & Ross Lift Station Wet Well
Figure 161: 3rd & Ross Lift Station Wet
Well Access Manhole
Figure 162: 3rd & Ross Lift Station Conduit Penetration

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 117 OCTOBER 2025
Electrical & Instrumentation Condition Photo(s)
▪ The pumps and electrical/controls
equipment we observed to be on top of the
wet well deck under a fiberglass enclosure.

The equipment did not appear to be rated for
a hazardous location and appeared to be at
the end of its useful life.
▪ No sealing fittings were observed on any
conduits on site but are required per the
National Electrical Code and California
Electrical Code on conduits once they leave a
hazardous area, such as the wet well. A lack
of sealing fittings is a safety hazard, a risk for
equipment damage, and is likely the reason
for H2S gas entering the electrical equipment
and the fiberglass enclosure.
▪ The existing level transducer appeared to be
hanging from its cable in the wet well, which
can cause premature failure of the cable.
▪ The level transducer penetration through the
wet well deck is inside the fiberglass
enclosure, is not sealed, and the cover can
be lifted without unbolting or unsealing the
cover. This could lead to an interpretation
that the inside of the pump and electrical
equipment enclosure is within a hazardous
envelope.
▪ The wet well manhole appeared to be 1 foot
or less from the pump/electrical enclosure,
does not seal properly, and has a small hole
in it. The manhole proximity plus the
ventilation openings observed in the
enclosure appear to put the pump/electrical
enclosure within a hazardous envelope.
▪ Cables, including power cables and the float
switch cable appeared damaged and should
be replaced.
▪ The float switch cable is run exposed (not in
conduit through the enclosure wall and into
the wet well, therefore the cable is not
protected from damage and the elements.
▪ An approximate 1.5-inch opening was
observed in the fiberglass enclosure where a
conduit may have been.
▪ City staff indicated that the pumps start and
stop based on signals from the level
transmitter.

Poor
Figure 163: 3rd & Ross Lift Station Fiberglass Enclosure with Equipment, Level Sensor Penetration and Manhole in Close Proximity
Figure 164: 3rd & Ross Lift Station Uncapped
Enclosure Opening

Figure 165: 3rd & Ross Lift Station Float Switch Cable
Outside Enclosure (Between Enclosure and Wet Well, Not
in Conduit)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 118 OCTOBER 2025
▪ Lift Station I/O appeared to be transmitted
off site using a Mission Communications
Cellular Wireless RTU.
▪ Existing electrical service was observed to be
240-volts, three-phase, 100 amps.
▪ The electrical service meter and main
breaker are severely corroded and should be
completely replaced.
▪ No arc flash stickers were observed on the
electrical equipment.
▪ No standby power generator or portable
generator connection was observed.
▪ The flexible conduits on site appeared to be
in poor condition and are degrading due to
exposure to the sun and elements.
▪ An office UPS was observed within the
pump/electrical equipment enclosure, not in
an electrical enclosure.
▪ No lighting was observed at this site.
▪ No intrusion switches were observed on site.
▪ No lift station discharge flowmeter was
observed.

Figure 166: 3rd & Ross Lift Station Utility Meter and
Main Breaker Condition
Climate Control Vulnerability Condition Photo(s)
Flooding
▪ Site grade around the lift station is dirt.
- Low point observed at the edge of the
pad. Ponding water at low points and/or
high groundwater may accelerate
deterioration of the wet well.

Electrical Outages
▪ No standby power generator or portable
generator connection was observed.

Extreme Heat
▪ Air cooling / temperature control not
observed inside electrical enclosures.

Poor

3.7.4 Hydraulic Assessment
The 3rd & Ross Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 3.6 times per hour on average with a maximum of 13 starts per hour. Pump #2 starts approximately 3.4 times per hour on average with a maximum of 28 starts per hour. Both pumps have a similar average number of starts per hour, however pump #2 has a higher maximum number of starts per hour based on the SCADA data received. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 7.5 HP, 4-pole (1450 rpm) motor should have a maximum number of

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 119 OCTOBER 2025

13.9 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed instances where the number of Pump #2 starts per hour has exceeded the NEMA recommended starts per hour. This may be indicative of an issue with the control logic of the pumps or an issue with the level control instrumentation. Dudek recommends for the City Operations staff to investigate the cause of this discrepancy. Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 201 minutes of run time per day (3,067 total hours) while pump #2 averages approximately 175 minutes of run time per day (2,668 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing 3rd & Ross Lift Station force main is a 4” Acrylonitrile Butadiene Styrene (ABS) pipe installed in 1988.

The condition of the force main is assumed to be fair to poor due to the age of the force main. The industry standard useful life of ABS is approximately 50 years. 3rd & Ross Lift Station is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the flow velocity through this existing 4” force main is estimated at approximately 8.3 ft/sec which exceeds HI velocity standards. It is recommended to replace the force main with 6” PVC piping in order to meet the HI velocity standards.

3.7.5 Recommended Improvements
Recommended improvements were developed for 3rd & Ross LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 31.

Table 31. 3rd & Ross Lift Station Recommended Improvements Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
EI&C
Move Utility
Pole, Meter, and
Main Breaker
Move all electrical and controls
equipment away from the wet
well, and outside of hazardous
envelope, provide working
clearance per NEC.

End of Useful
Life
Power and
Generator
Program
(Near-term)
EI&C/
Climate
Change
Vulnerability
Install MTS &
Generator
Receptacle
Install a manual transfer switch
and generator receptacle to
allow powering the site from a
portable generator when utility
power is down.

Safety Risk
Power and
Generator
Program
(Near-term)
EI&C/
Climate
Change
Vulnerability
Replace All
Electrical,
Instrumentation,
and Controls
Replace all electrical,
instrumentation, and control.

Put electrical, pump control
panel, level transmitter, RTU,
and all other equipment on a
rack outside of the hazardous
envelope. Install sealing fittings
Code
Violation/
Operational
Failure
Instrumentation
and Control
Program –
Phase 2
(Mid-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 120 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
on all conduits that enter the
hazardous envelope in
accordance with NFPA 820 and
NEC. This will likely require
expanding the site footprint
(fence). Install air cooling /
temperature control inside
electrical enclosures to account
for rising temperatures.

EI&C Install Sealing
Fittings
Install conduit sealing fittings
on all conduits as they exit the
hazardous envelope (including
the wet well) and before they
enter any enclosures or junction
boxes.

Code
Violation/
Operational
Failure
Maintenance
EI&C
Perform Power
System Study &
Install Arc Flash
Stickers
Per NFPA 70E, a power system
study should be performed, and
updated every 5 years. Updates
should be made whenever
modifications are made. Arc
flash stickers should be
provided on the electrical
equipment.

Safety Risk
Arc Flash /
Short Circuit
Study Program
(Near-term)
EI&C
Seal All
Penetrations
Through Wet
Well Deck
All penetrations through wet
well deck should be sealed per
NFPA 820 and NEC.

Code
Violation Maintenance
EI&C
Replace and
Upgrade the
Level Transducer
Mounting and
Penetration
A new pipe sleeve and flange to
mount the transducer to and
connect the conduit to, with a
sealing fitting, and penetration
concrete repairs could address
the hazardous envelope barrier
concern and sensor mounting.

Alternately, the penetration
could be permanently sealed
and the level transducer
relocated away from the
electrical and controls
equipment, or the controls
equipment replaced and moved
outside of the enclosure and
hazardous envelope and the
motors replaced with motors
rated for a Class 1, Division 1
hazardous location.

Code
Violation/
Operational
Failure
Maintenance
EI&C
Replace High
Level Float,
Install Cable in
Install new float switch, cable,
conduit, and sealing fitting.

Ensure high level signal is
Code
Violation/ Maintenance

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 121 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Conduit with
Sealing Fitting
transmitted via AT&T phone line
to staff.

Operational
Failure
EI&C
Replace All
Flexible
Conduits
In poor condition. End of Useful
Life Maintenance
EI&C Provide Site
Task Lighting
To provide adequate lighting for
staff on site to work, maintain,
and troubleshoot.

Safety Risk
3rd & Ross Lift
Station
Rehabilitation
(Long-term)
EI&C Install Intrusion
Switches
Intrusion switches on site gate,
electrical equipment, control
panel and have report to RTU.

Security Risk Maintenance
EI&C Install Discharge
Flow Meter
Install flowmeter on pump
discharge to allow flow
monitoring which provides
useful operational data and
serves as an indication of
diminishing pump performance
over time.

Operations
Preference
Pumps, Piping,
Supports, and
HVAC Program
(Mid-term)
Site Civil/
Mechanical
On-Site Water
Connection
Install an on-site water connection to
provide a water supply for site washdown.

Preventative
Maintenance
3rd & Ross Lift
Station
Rehabilitation
(Long-term)
Site Civil/
Mechanical
/ Climate
Change
Vulnerability
Site Grading
There is a low point in the unpaved
area adjacent to the dry well top slab
where surface runoff ponds up.

During heavy rains, the
accumulation of water in this area is
most likely seeping down along the
exterior of the dry well structure and
infiltrating through the existing
conduit and duct wall penetrations.

The depressed area also poses a
tripping hazard for operations staff.

Preventative
Maintenance
3rd & Ross Lift
Station
Rehabilitation
(Long-term)
Mechanical
Recoat Existing
Above Grade
Mechanical
Equipment
The existing above grade pumps,
suction and discharge mechanical
piping, and valves are experiencing
varying levels of minor to moderate
minor corrosion and coating
delamination occurring in several
locations.

Coating
Delamination
/ Failure
Maintenance
Mechanical
Replace Existing
Force Main
within Wet Well
Pump discharge piping (force
main) within wet well was observed
to be severely corroded and is
experiencing significant loss of
Operational
Failure
Pumps, Piping,
Supports, and
HVAC Program
(Mid-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 122 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
pipe wall thickness. This section of
the force main is at high risk of
failure. The force main is
undersized and the velocities
within the piping exceed the HI
standards for pipe velocity.

Mechanical
Install Lift
Station Bypass
Connection
There is no existing bypass
connection for this lift station. It is
recommended to install a force
main bypass connection in the
event of a lift station failure.

Increased
SSO
Potential
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 2
(Mid-term)
Structural
Replace Wet
Well Top Slab
and Access
Hatch
The existing wet well access
manhole frame and cover were
observed to be moderately
corroded providing a safety risk for
operations. Additionally, the
manhole cover is not a standard lid
and the manhole ring appeared to
have disconnected from the wet
well top slab. It is recommended to
replace the wet well access cover
with new hatches that are
equipped with integrated fall
protection, slam lock, and lift
assist. Alternatively, a composite
manhole cover can be retrofitted
around the existing access cover
frame to mitigate the immediate
safety concern.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)

3.8 4th & Wake Lift Station

3.8.1 Location and Layout
The 4th & Wake Lift Station is located at the northeastern corner of the intersection of Wake Avenue and S 4th Street. Site access for this lift station is a chain-link gate on the east side of the facility. There is no dedicated parking at the 4th & Wake Lift Station however the adjacent parking lot to the northeast can be used. The lift station is a self-priming duplex station with lift up fiberglass enclosure located within a small, fenced site.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 123 OCTOBER 2025
Figure 167: 4th & Wake Lift Station Location
Figure 168: 4th & Wake Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 124 OCTOBER 2025

3.8.2 System Characteristics

3.8.2.1 Pump Station
A summary of the pumping units for 4th & Wake LS is provided on Table 32, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 33.

Table 32. 4th & Wake Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Gorman Rupp Model T4A3-B Gorman Rupp Model T4A3-B Pump Type Self Priming Self Priming
Pump Mount Guide Rail System
Design Capacity 200 gpm @ Unknown TDH
Motor, hp 10
Motor Operation Constant Speed
Speed, rpm 1750
Discharge Diameter, inches 4
Year Installed 1985
Table 33. 4th & Wake Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete
Diameter, feet 5.5
Depth, feet 19.9
Floor Elevation, feet -53.9
Influent Sewer Invert, feet -46.4
Cover/Hatch Type 24” Manhole
Bypass Assembly
Valve Location Above grade fiberglass enclosure
Bypass Connection 4” cleanout
Force Main
Diameter, inches 4”
Length, feet 334
Material PVC

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 125 OCTOBER 2025

3.8.2.2 Operations and Maintenance History
Operations reported that fats, oils, and grease (FOG) accumulate in the wet well; however, regular cleaning has prevented significant buildup. During onsite inspections, Dudek observed that the existing enclosure is small and difficult to work in. During the inspection it was discovered that the level control floats were obstructed by the suction pipe and its support. Onsite testing confirmed that the floats were faulty and did not activate the alarm system. Additionally, operations noted past instances of ragging in the check valves, but consistent maintenance has ensured proper functionality.

3.8.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at the 4th & Wake Lift Station. Table 34 contains observations made during the February 12, 2025 site inspection and information provided by the City during the pre- and post-inspection workshops. During the April 8, 2025 post inspection workshop, the City indicated that the 4th & Wake Lift Station will be abandoned by 2030. Flows previously served by this lift station will be redirected via gravity to the new Southern Lift Station which will replace this lift station.

Table 34. 4th & Wake Lift Station Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ Site perimeter fence is in excellent condition
and contains privacy slats.
- Fiberglass enclosure was unlocked at the
time of the inspection.
- No security issues reported at this site.
▪ Lift station concrete pad is in good condition.
- Site grade around the pad is dirt and
sloping away from the wet well and
enclosure.
▪ Site has a water meter with a backflow
preventor and hose.
- The water meter was not assessed during
the field inspections.
- The backflow preventor was observed to
be in fair condition with moderate
oxidation and corrosion.

Fair/Good

Figure 169: 4th & Wake Lift Station Concrete Pad
(Left), Water Meter Backflow Preventer (Right)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 126 OCTOBER 2025
Mechanical Condition Photo(s)
Pumps
▪ Self-priming pumps appear to be in good
condition.
- Minor corrosion and delamination
observed.
- Pumps are belt driven. Belts are
protected by belt guards.

Piping & Valves
▪ Suction and discharge piping within wet well
is PVC and in fair condition.
- PVC chalking observed.
▪ 4” force main clean out located within site
fence perimeter.
▪ Discharge and suction piping and valves
within the above grade fiberglass enclosure
is in good to fair condition.
- Minor to moderate corrosion and coating
delamination observed on ductile iron
piping and fittings.

Suction and discharge piping transitions to
ductile iron once above grade. PVC appears
to be in good condition.

Good
Good
Figure 172: 4th & Wake Lift Station Self-Priming Pumps
Figure 171: 4th & Wake Lift Station Suction and
Discharge Piping Within Wet Well
Figure 170: 4th & Wake Lift Station Suction and
Discharge Piping Above Grade

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 127 OCTOBER 2025
Structural Condition Photo(s)
Wet Well
▪ Concrete structure was observed to be
exhibiting severe corrosion from H2S
exposure.
- Aggregate and rebar were exposed within
wet well.
- Extreme loss of wall thickness and
concrete spalling.
▪ Concrete wet well top slab was observed to
be exhibiting severe corrosion from H2S
exposure.
- Loss of slab thickness.
- Large aggregate is exposed.
▪ Wet well access manhole is custom made
(non-standard) and observed to be
moderately to severely corroded.
▪ Wet well vault did not appear to be sealed
causing surrounding environment and
fiberglass enclosure to a hazardous location
per NFPA 820.
▪ Piping within wet well was observed to be in
good condition.
▪ Submersible pumps were not pulled for
assessment during field inspections
▪ Unistrut suction piping supports are
moderately to severely corroded within wet
well.
- Pipe supports point of contact with wet
well is corroded and chipping. It is likely
that the corroded support is accelerating
the wet well deterioration at this location.

Poor

Figure 173: 4th & Wake Lift Station Wet Well
Concrete Condition

Figure 174: 4th & Wake Lift Station Wet Well Top Slab

Figure 175: 4th & Wake Lift Station Wet Well
Access Manhole

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 128 OCTOBER 2025
Electrical & Instrumentation Condition Photo(s)
▪ The pumps and electrical/controls
equipment were observed to be on top of the
wet well deck under a fiberglass enclosure.

The equipment did not appear to be rated for
a hazardous location.
▪ No sealing fittings were observed on any
conduits on site but are required per the
National Electrical Code and California
Electrical Code on conduits once they leave a
hazardous area, such as the wet well. A lack
of sealing fittings is a safety hazard, a risk for
equipment damage, and H2S gas entering
the electrical equipment and the fiberglass
enclosure.
▪ The existing level transducer appeared to be
hanging from its cable in the wet well, which
can cause premature failure of the cable.
▪ The level transducer penetration through the
wet well deck is inside the fiberglass
enclosure is not sealed. The cover can be
lifted without unbolting or unsealing the
cover—it appeared to simply rest on the
concrete deck. This could lead to an
interpretation that the inside of the pump
and electrical equipment enclosure is within
a Class 1, Division 1 hazardous envelope.
▪ The wet well manhole appeared to be 1 foot
or less from the pump/electrical enclosure,
does not seal properly, and has a small hole
in it. The manhole proximity plus the
ventilation openings observed in the
enclosure could put the pump/electrical
enclosure within a hazardous envelope. A
vent is in the fiberglass enclosure wall near
the manhole.
▪ One pump motor appeared to be rated for
Class 1, Division 2 hazardous locations, and
to other pump motor did not appear to be
rated for hazardous locations.
▪ There are noticeably visible gaps/openings
between the piping and the concrete deck as
the piping enters the wet well. H2S gas is
entering the enclosure where the pumps and
electrical equipment are located. This plus
the level transducer opening could make the
area within the fiberglass enclosure a Class
1, Division 1 hazardous location until
modifications are made.

Poor
Figure 176: 4th & Wake Lift Station Fiberglass
Enclosure with Equipment, Level Penetration Inside and
Manhole in Proximity
Figure 177: 4th & Wake Lift Station Level
Transducer Penetration Inside the Fiberglass Enclosure

Figure 178: 4th & Wake Lift Station Example of
Gap/Opening to Wet Well

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 129 OCTOBER 2025
▪ The existing pump control panel appeared to
have been replaced at some point in time—it
did not appear to be the original pump
control panel. The control panel did not
appear to be rated for a hazardous location,
and corrosion was observed inside the
control panel, likely from H2S gas. It also
appeared to have been field modified over
time.
▪ There is a receptacle, a snap switch, and
exposed wiring and wiring connections inside
the fiberglass enclosure.
▪ City staff indicated that the pumps start and
stop based on signals from the level
transmitter.
▪ Lift Station I/O appeared to be transmitted
off site using a Mission Communications
Cellular Wireless RTU.
▪ Per staff, the high-level float switch signal is
transmitted via an AT&T phone line.
▪ City staff tested the high-level float during
the site visit and determined it to be
inoperable.
▪ Existing electrical service was observed to be
240-volts, three-phase, 100 amps.
▪ The electrical service meter is in fair
condition and has surface corrosion.
▪ The main breaker enclosure is a safety
hazard and code violation in its current
condition. When opening the enclosure,
there is no dead front, so the breaker, all
terminations, and wiring are exposed.
▪ There is conduit damage at the fiberglass
enclosure for the power conduit from the
main breaker that appeared to be from
ground settling. It appeared that duct tape
was previously used to seal the conduit at
the two breaking points.
▪ No arc flash stickers were observed on the
electrical equipment.
▪ No standby power generator or portable
generator connection was observed.
▪ An office Uninterruptible Power Supply (UPS)
was observed within the pump/electrical
equipment enclosure.
▪ No lighting was observed at this site.
▪ No intrusion switches were observed on site.

Figure 179: 4th & Wake Lift Station Receptacle and Swich (Left), Exposed Wires and Terminations (Right)
Figure 180: 4th & Wake Lift Station Electrical Utility Meter and Main Breaker Enclosure
Figure 181: 4th & Wake Lift Station Broken
Power Conduit

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 130 OCTOBER 2025
▪ No lift station discharge flowmeter was
observed.
▪ Air cooling / temperature control not
observed inside electrical enclosures.

Climate Control Vulnerability Condition Photo(s)
Flooding
▪ Site grade around the pad is dirt and sloping
away from the wet well and enclosure.

Electrical Outages
▪ No standby power generator or portable
generator connection was observed.

Extreme Heat
▪ Air cooling / temperature control not
observed inside electrical enclosures.

Fair

3.8.4 Hydraulic Assessment
The 4th & Wake Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 2.3 times per hour on average with a maximum of 35 starts per hour. Pump #2 starts approximately 2.1 times per hour on average with a maximum of 26 starts per hour. Both pumps have a similar average number of starts per hour, however pump #1 has a higher maximum number of starts per hour based on the SCADA data received. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 10 HP, 4-pole (1750 rpm) motor should have a maximum number of 12.5 motor starts per hour. It was observed that the instances number of starts per hour exceeds the NEMA recommended starts per hour based on the provided SCADA data. This indicates that the existing operational set points may need to be adjusted. Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 105 minutes of run time per day (1,594 total hours) while pump #2 averages approximately 101 minutes of run time per day (1,545 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Legacy Lift Station force main is a 4” PVC pipe installed in 1985. The force main condition is assumed to be fair due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. 4th & Wake Lift Station is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the flow velocity through this existing 4” force main is estimated at approximately 5.1 ft/sec which is in accordance with HI standards.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 131 OCTOBER 2025

3.8.5 Recommended Improvements
Recommended improvements were developed for 4th & Wake LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 35.

Table 35. 4th & Wake Lift Station Recommended Improvements Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/ Risk
Associated
Project (Term)
EI&C
Replace Site
Main Breaker
Enclosure
Exposed breaker, terminations,
wiring inside Safety Risk
Instrumentation
and Control
Program –
Phase 1
(Near-term)
EI&C/
Climate
Change
Vulnerability
Install MTS &
Generator
Receptacle1
Install a manual transfer switch
and generator receptacle to
allow powering the site from a
portable generator when utility
power is down.

Operational
Failure N/A
EI&C/
Climate
Change
Vulnerability
Replace All
Electrical,
Instrumentation,
and Controls2
Replace all electrical,
instrumentation, and control.

Put electrical, pump control
panel, level transmitter, RTU,
and all other equipment on a
rack outside of the hazardous
envelope. Install sealing fittings
on all conduits that enter the
hazardous envelope in
accordance with NFPA 820 and
NEC. This will likely require
expanding the site footprint
(fence). Install air cooling /
temperature control inside
electrical enclosures to account
for rising temperatures.

Code
Violation/
Operational
Failure
N/A
EI&C Install Sealing
Fittings
Install conduit sealing fittings
on all conduits as they exit the
hazardous envelope (including
the wet well) and before they
enter any enclosures or junction
boxes.

Code
Violation/
Operational
Failure
Maintenance
EI&C
Perform Power
System Study &
Install Arc Flash
Stickers
Per NFPA 70E, a power system
study should be performed, and
updated every 5 years Updates
should be made whenever
modifications are made. Arc
flash stickers should be
provided on the electrical
equipment.

Safety Risk
Arc Flash /
Short Circuit
Study Program
(Near-term)
EI&C Seal All
Penetrations
All penetrations through wet
well deck should be sealed per
Code
Violation
Maintenance

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 132 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/ Risk
Associated
Project (Term)
Through Wet
Well Deck
NFPA 820 and NEC.

EI&C
Replace and
Upgrade the
Level Transducer
Mounting and
Penetration
A new pipe sleeve and flange to
mount the transducer to and
connect the conduit to, with a
sealing fitting, and penetration
concrete repairs could address
the hazardous envelope barrier
concern and sensor mounting.

Alternately, the penetration
could be permanently sealed
and the level transducer
relocated away from the
electrical and controls
equipment, or the controls
equipment replaced and moved
outside of the enclosure and
hazardous envelope and the
motors replaced with motors
rated for a Class 1, Division 1
hazardous location.

Code
Violation/
Operational
Failure
Maintenance
EI&C
Replace high
level float (if
needed) conduit
and install
sealing fitting
Install new float switch, cable,
conduit, and sealing fitting.

Ensure high level signal is
transmitted via AT&T phone line
to staff.

Code
Violation/
Operational
Failure
Maintenance
EI&C Replace all
flexible conduits In poor condition. End of Useful Life Maintenance EI&C Provide site task
lighting1
To provide adequate lighting for
staff on site to work, maintain,
and troubleshoot.

Safety Risk N/A
EI&C Install intrusion
switches
Intrusion switches on site gate,
electrical equipment, control
panel and have report to RTU.

Security Risk Maintenance
EI&C Install discharge
flow meter1
Install flowmeter on pump
discharge to allow flow
monitoring which provides
useful operational data and
serves as an indication of
diminishing pump performance
over time.

Operations
Preference N/A
EI&C Replace motors1
Replace motors with Class 1,
Division 1 hazardous location
rated motors.

Code
Violation/
Operational
Failure
N/A
EI&C
Repair wet well
deck and seal all
openings1
Repair wet well concrete and
seal all openings to wet well—
gaps around piping, level
transducer opening, nearby
Code
Violation/
Operational
Failure
N/A

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 133 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/ Risk
Associated
Project (Term)
manhole lid with opening.

EI&C
Repair /replaced
damaged
conduit
Repair or replace broken power
conduit due to ground settling
Operational
Failure Maintenance
EI&C /
Climate
Change
Vulnerability
Install Electrical
Panel Air Cooling
and
Temperature
Control1
Install air cooling / temperature
control inside electrical
enclosures to account for rising
temperatures.

Preventative
Maintenance N/A
Mechanical
Recoat Existing
Above Grade
Mechanical
Equipment
The existing above grade
pumps, suction and discharge
mechanical piping, and valves
are experiencing varying levels
of minor to moderate minor
corrosion and coating
delamination occurring in
several locations.

Coating
Delamination
/ Failure
Maintenance
Mechanical
Replace Existing
Pipe Supports in
Wet Well
Unistrut suction piping supports
are moderately to severely
corroded within wet well.

Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)
Structural
Replace Wet
Well Access
Cover
The existing wet well access
manhole frame and cover were
observed to be moderately
corroded providing a safety risk for
operations. Additionally, the
manhole cover is not a standard lid
making replacement more difficult.

It is recommended to replace the
wet well access cover with new
hatches that are equipped with
integrated fall protection, slam
lock, and lift assist. Alternatively, a
composite manhole cover can be
retrofitted around the existing
access cover frame to mitigate the
immediate safety concern.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)
Structural Rehab of Wet
Well
Wet well concrete was observed
to be cracked and severely
corroded with exposed and
damaged rebar. Concrete wet
well top slab was observed to be
exhibiting severe corrosion from
H2S exposure. Wet well is in
critical/poor condition and is at
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 134 OCTOBER 2025

1. This recommended improvement is assumed to not be required due to the planned decommission of the lift station within one year of writing this technical memorandum. If the lift station is in service beyond the currently scheduled decommission timeline, then it is recommended that the City perform this improvement.

2. Should the City address electrical code violations and seal all penetrations and conduits at wet well, this recommendation would not be required.

3.9 8th & Wake Lift Station

3.9.1 Location and Layout
The 8th & Wake Lift Station is located at the northeast side of the S 8th Street and Wake Avenue intersection.

Parking for this facility is the dirt lot adjacent to the lift station on its east side. The lift station is a self-priming duplex station with lift up fiberglass enclosure located within a small, fenced site.

Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/ Risk
Associated
Project (Term)
high risk of catastrophic failure.

Slip line existing wet well with
FRP basin, install cast in place
manhole liner, or completely
replace the existing wet well.

Figure 182: 8th & Wake Lift Station Location

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 135 OCTOBER 2025

3.9.2 System Characteristics

3.9.2.1 Pump Station
A summary of the pumping units for 8th & Wake LS is provided on Table 36, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 37.

Table 36. 8th & Wake Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Barrett Pump Pioneer P6 Barrett Pump Pioneer P6 Pump Type Self Priming Self Priming
Pump Mount Above grade
Design Capacity 200 gpm @ 35’ TDH
Motor, hp 5
Motor Operation Constant Speed
Speed, rpm 1800
Discharge Diameter, inches 4
Year Installed 2006
Figure 183: 8th & Wake Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 136 OCTOBER 2025
Table 37. 8th & Wake Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete with polyurethane liner
Diameter, feet 8
Depth, feet 20.50
Floor Elevation, feet -52.50
Influent Sewer Invert, feet -46.5
Cover/Hatch Type 24” Manhole
Bypass Assembly
Valve Location Above grade fiberglass enclosure
Bypass Connection None
Force Main
Diameter, inches 6”
Length, feet 136.5
Material PVC

3.9.2.2 Operations and Maintenance History
There were no operational concerns reported at this facility.

3.9.3 Inspection Summary
Dudek performed a wet well assessment 8th & Wake LS. Table 38 contains observations made during the February 12, 2025 wet well condition assessment and information provided by the City during the pre- and post-inspection workshops.

Although a comprehensive inspection was not performed at 8th & Wake LS, it is assumed that the facility follows the trends observed at other facilities including electrical code violations, missing arc flash studies and warning labels, absence of emergency generators or receptacles, and lack of bypass pumping connections.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 137 OCTOBER 2025
Table 38. 8th & Wake Lift Station Inspection Summary
Structural Condition Photo(s)
Wet Well
▪ Wet well access manhole cover is severely
corroded.
▪ Wet well concrete slab at access manhole is
corroded and spalling has occurred.
- Concrete sections may fall and damage
pumps.
▪ Wet well liner was observed to be bubbling
and delaminated in several locations.
▪ Wet well liner appears to have a breach at
liner termination.
- Unable to determine concrete condition
behind liner.
▪ There are no conduit seal offs observed to be
installed on conduits leaving the wet well,
which allows hazardous gases into the
electrical equipment and enclosure.
▪ The wet well manhole cover and level sensor
penetration are less than 1 foot away from
the green enclosure, the manhole cover has
a small hole in it, and it is assumed that the
green enclosure is not sealed to keep gases
out. This would require classifying the green
enclosure area as a hazardous location and
relocating all electrical and control
equipment out of the green enclosure and
away from the wet well per NFPA 820.
▪ Submersible pumps were not pulled for
assessment during field inspections
Poor
Figure 184: 8th & Wake Lift Station Wet Well Concrete at Access Manhole
Figure 185: 8th & Wake Lift Station Wet Well Walls

Figure 186: 8th & Wake Lift Station Wet Well Liner

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 138 OCTOBER 2025
Figure 187: 8th & Wake Lift Station Transducer
Penetration and Wet Well Access

3.9.4 Hydraulic Assessment
The 8th & Wake Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 1.2 times per hour on average with a maximum of 6 starts per hour. Pump #2 starts approximately 1.2 times per hour on average with a maximum of 11 starts per hour. Both pumps have a similar average number of starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 5 HP, 4-pole (1800 rpm) motor should have a maximum number of 16.3 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed that both pumps are in compliance with the number of starts per hour.

Pump #1 averages 50.8 minutes of run time per day (773 total hours) while pump #2 averages approximately 59.3 minutes of run time per day (904 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing 8th & Wake Lift Station force main is a 6” PVC pipe installed in 2006. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. 8th & Wake Lift Station is a duplex lift station that is assumed to operate in a duty/standby configuration.

With one pump in operation, the flow velocity through this existing 6” force main is estimated at approximately 2.3 ft/sec which is in accordance with HI standards.

3.9.5 Recommended Improvements
Recommended improvements were developed for 8th & Wake LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 39.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 139 OCTOBER 2025
Table 39. 8th & Wake Lift Station Recommended Improvements Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
Mechanical Replace
Existing Pumps
Submersible pumps were not pulled
for assessment during field
inspections, however it is anticipated
that the existing pumps are either at
or near the end of their useful life.

End of
Useful Life
8th & Wake
Lift Station
Rehabilitation
(Long-term)
Mechanical
Install Lift
Station Bypass
Connection
There is no existing bypass
connection for this lift station. It is
recommended to install a force main
bypass connection in the event of a
lift station failure.

Increased
SSO
Potential
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 2
(Mid-term)
Structural
Replace Wet
Well Access
Cover
The existing wet well access manhole
frame and cover were observed to be
moderately corroded providing a
safety risk for operations. It is
recommended to replace the wet well
access cover with new hatches that
are equipped with integrated fall
protection, slam lock, and lift assist.

Alternatively, a composite manhole
cover can be retrofitted around the
existing access cover frame to
mitigate the immediate safety
concern.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)
Structural Replace Wet
Well Liner
Wet well liner was observed to be
separating from concrete and
delaminating in several locations. Wet
well liner appears to have a breach at
liner termination at the bottom of the wet
well and within the wet well access shaft.

Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 140 OCTOBER 2025

3.10 Lift Station No. 2

3.10.1 Location and Layout
Lift Station No. 2 is located northwest of the intersection of South La Brucherie Road and Wake Avenue. The lift station is a full sized dry well / wet well lift station within a block wall facility. This site can be accessed by a chainlink slide gate on Wake Avenue. There is ample room within the CMU block wall facility for parking.

Figure 188: Lift Station No. 2 Location
Figure 189: Lift Station No. 2 Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 141 OCTOBER 2025

3.10.2 System Characteristics

3.10.2.1 Pump Station
A summary of the pumping units for Lift Station No. 2 is provided on Table 40, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 41.

Table 40. Lift Station No. 2 Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Vaughan SE4T3 Chopper Vaughan SE4T3 Chopper
Pump Type Submersible Submersible
Pump Mount Guide Rail System
Design Capacity unknown
Motor, hp 15
Motor Operation Constant Speed
Speed, rpm 1800
Discharge Diameter, inches 4
Year Installed 1975, rehabilitated in 2016
Table 41. Lift Station No. 2 Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Lined precast concrete
Diameter, feet 10
Depth, feet 26.4
Floor Elevation, feet -52.3
Influent Sewer Invert, feet -45.3
Cover/Hatch Type 43” x 66” Access Hatch
Valve Vault
Size, feet 12 x 8
Material Cast in place concrete
Depth, feet 8.5
Cover/Hatch Type 50” x 74” aluminum hatch
Bypass Assembly
Valve Location N/A
Bypass Connection None
Force Main
Diameter, inches 12
Length, feet 981
Material PVC

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 142 OCTOBER 2025

3.10.2.2 Operations and Maintenance History
Lift Station No. 2 was constructed in 1975 and replaced in 2016. The lift station replacement included new wet well, submersible pumps, valve vault, emergency backup generator, and MCC/pump control panel. There were no operational concerns reported at this facility.

3.10.3 Inspection Summary
Dudek performed a wet well assessment for Lift Station No. 2. Table 42 contains observations made during the February 12, 2025 wet well condition assessment and information provided by the City during the pre- and postinspection workshops.

Although a comprehensive inspection was not performed at Lift Station No. 2, it is assumed that the facility follows the trends observed at other facilities including electrical code violations, missing arc flash studies and warning labels, absence of emergency generators or receptacles, and lack of bypass pumping connections.

Table 42. Lift Station No. 2 Inspection Summary
Structural Condition Photo(s)
Wet Well
▪ Wet well structure appeared to be in
excellent condition. Little to no corrosion
observed.
▪ Integral fall protection observed at the wet
well access hatch and is in good condition.
- Protection grating coating has begun
delaminating and grating has minor
corrosion.
- The hatches and framing were observed
to be in excellent condition.
▪ Submersible pumps were not pulled for
assessment during field inspections
▪ Piping within the wet well was observed to be
in good to fair condition.
▪ No bypass connection
Excellent
Figure 190: Lift Station No. 2 Access Hatch (Above) and Wet Well (Below)

3.10.4 Hydraulic Assessment
The Lift Station No. 2 hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 1.5 times per hour on average with a maximum of 11

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 143 OCTOBER 2025
starts per hour. Pump #2 starts approximately 1.6 times per hour on average with a maximum of 16 starts per hour.

Both pumps have a similar average number of starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 15 HP, 6-pole (1160 rpm) motor should have a maximum number of 12.1 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed instances where Pump #2’s starts per hour has exceeded the NEMA recommended starts per hour. This indicates that the existing operational set points may need to be adjusted to reduce the number of starts per hour. Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 205 minutes of run time per day (3,121 total hours) while pump #2 averages approximately 268 minutes of run time per day (4,082 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Lift Station No. 2 force main is a 12” PVC pipe installed in 2016. The condition of the force main is assumed to be excellent due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. Lift Station No. 2 is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the flow velocity through this existing 12” force main is estimated at approximately 2.4 ft/sec which is in accordance with HI standards.

3.10.5 Recommended Improvements
Recommended improvements were developed for Lift Station No. 2 based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 43.

Table 43. Lift Station No. 2 Recommended Improvements
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated Project
(Term)
Mechanical
Install Lift Station
Bypass
Connection
There is no existing bypass
connection for this lift
station. It is recommended to
install a force main bypass
connection in the event of a
lift station failure.

Increased
SSO
Potential
Structures,
Hatches / Doors
and Bypass
Connection
Program – Phase 1
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 144 OCTOBER 2025

3.11 Orange Lift Station

3.11.1 Location and Layout
The Orange Lift Station is located on the south side of West Orange Avenue between Lotus Avenue and Haskell Road. The lift station is a self-priming duplex station with lift up fiberglass enclosure located within a block wall and fenced site. Parking can be found on West Orange Avenue or within the facility.

Figure 191: Orange Lift Station Location
Figure 192: Orange Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 145 OCTOBER 2025

3.11.2 System Characteristics

3.11.2.1 Pump Station
A summary of the pumping units for Orange LS is provided on Table 44, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 45.

Table 44. Orange Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Barrett Pump Pioneer P4 Barrett Pump Pioneer P4 Pump Type Self Priming Self Priming
Pump Mount Above Grade
Design Capacity 300 gpm @ 20’ TDH (Provided by City)
Motor, hp 10
Motor Operation Constant Speed
Speed, rpm 1750
Discharge Diameter, inches 4
Year Installed 2005
Table 45. Orange Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Lined precast concrete
Diameter, feet 7
Depth, feet 18.7
Floor Elevation, feet -53.3
Influent Sewer Invert, feet -46.6
Cover/Hatch Type 24” Manhole
Bypass Assembly
Valve Location Above grade fiberglass enclosure
Bypass Connection Yes
Force Main
Diameter, inches 4
Length, feet 62
Material PVC

3.11.2.2 Operations and Maintenance History
Operations informed that the pumps were replaced recently at Orange Lift Station. There were no operational concerns reported at this facility.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 146 OCTOBER 2025

3.11.3 Inspection Summary
Dudek performed a wet well assessment for the Orange Lift Station. Table 46 contains observations made during the February 12, 2025 wet well condition assessment and information provided by the City during the pre- and post-inspection workshops.

Although a comprehensive inspection was not performed at Lift Station No. 2, it is assumed that the facility follows the trends observed at other facilities including electrical code violations, missing arc flash studies and warning labels, absence of emergency generators or receptacles, and lack of bypass pumping connections.

Table 46. Orange Lift Station Inspection Summary
Structural Condition Photo(s)
Wet Well
▪ Wet well access manhole and manhole ring
are severely corroded.
▪ Moderate to severe concrete corrosion within
the wet well observed at locations where the
liner is failing.
▪ Wet well liner is failing and flaking off in
sheets.
- Liner failure at various points throughout
wet well.
▪ PVC suction and discharge (force main)
piping appear to be in fair condition within
wet well.
▪ Flexible conduits exposed to the outdoors
have completely failed.
▪ There are no conduit seal offs installed on
conduits leaving the wet well or conduits
entering the hazardous area, which allows
hazardous gases into the electrical
equipment and enclosure.
▪ The wet well manhole cover and level sensor
penetration are right up against the green
enclosure, and it is assumed that the green
enclosure is not sealed to keep gases out.

This would require classifying the green
enclosure area as a hazardous location and
relocating all electrical and control
equipment out of the green enclosure and
away from the wet well per NFPA 820.
▪ Operations informed that the force main
bypass is located on West Orange Avenue.

Excellent
Figure 193: Orange Lift Station Wet Well Structure
Figure 194: Orange Lift Station Wet Well Manhole Cover
(Top Left), Wet Well Access Manhole (Top Right), Level
Sensor Penetration (Bottom)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 147 OCTOBER 2025

3.11.4 Hydraulic Assessment
The Orange Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 2.0 times per hour on average with a maximum of 15 starts per hour. Pump #2 starts approximately 1.5 times per hour on average with a maximum of 20 starts per hour. Both pumps have a similar average number of starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 10 HP, 4-pole (1750 rpm) motor should have a maximum number of 12.5 motor starts per hour. . It was observed that the instances number of starts per hour exceeds the NEMA recommended starts per hour based on the provided SCADA data. This indicates that the existing operational set points may need to be adjusted to reduce the number of starts per hour. Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 97.5 minutes of run time per day (1,486 total hours) while pump #2 averages approximately

74.5 minutes of run time per day (1,137 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Orange Lift Station force main is a 4” PVC pipe installed in 2005. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. The flow velocity through this existing 4” force main is estimated at approximately 7.7 ft/sec which exceeds the HI standards. Orange Lift Station is a duplex lift station that is assumed to operate in a duty/standby configuration.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 148 OCTOBER 2025

3.11.5 Recommended Improvements
Recommended improvements were developed for Orange LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 47.

Table 47. Orange Lift Station Recommended Improvements
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project
(Term)
Structural
Replace Wet
Well Access
Cover
The existing wet well access manhole
frame and cover were observed to be
moderately corroded providing a safety
risk for operations. It is recommended to
replace the wet well access cover with
new hatches that are equipped with
integrated fall protection, slam lock, and
lift assist. Alternatively, a composite
manhole cover can be retrofitted around
the existing access cover frame to
mitigate the immediate safety concern.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)
Structural Replace Wet
Well Liner
Moderate to severe corrosion of the
concrete wet well observed at liner
failures. The wet well liner is failing and
flaking off in sections in several areas.

The liner is also failing at all wet well
penetrations.

Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 149 OCTOBER 2025

3.12 Lift Station No. 1

3.12.1 Location and Layout
Lift Station No. 1 is located south of West McCabe Road, west of the Imperial County Office of Education Building E. The lift station is packaged dry well/wet well facility. The wet well hatch is located within West McCabe Road and traffic control has to be implemented to access the wet well. The dry well is within a small, fenced enclosure adjacent to the road. Parking can be found in the dirt lot south of the dry well.

Figure 195: Lift Station No. 1 Location
Figure 196: Lift Station No. 1 Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 150 OCTOBER 2025

3.12.2 System Characteristics

3.12.2.1 Pump Station
A summary of the pumping units for Lift Station No. 1 LS is provided on Table 48, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed.

Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 49.

Table 48. Lift Station No. 1 Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Gorman Rupp T6A3S-B Gorman Rupp T6A3S-B
Pump Type Self Priming Dry Well Self Priming Dry Well
Pump Mount Guide Rail System
Design Capacity 400 gpm @ 14.6 TDH
Motor, hp 5
Motor Operation Constant Speed
Speed, rpm 1725
Discharge Diameter, inches 6
Year Installed 1975
Table 49. Lift Station No. 1 Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete with liner
Diameter, feet 6
Depth, feet 18
Floor Elevation, feet -40.52
Influent Sewer Invert, feet -34.27
Cover/Hatch Type 24” Manhole
Valve Vault
Size, inches 90
Material Reinforced Fiber Glass Dry Well
Depth, feet N/A
Cover/Hatch Type 24” diameter hatch
Bypass Assembly
Valve Location N/A
Bypass Connection None
Force Main
Diameter, inches 6
Length, feet 182
Material PVC

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 151 OCTOBER 2025

3.12.2.2 Operations and Maintenance History
This facility historically has experienced ragging issues. Operations installed the “Eradicator” solids management system which has improved the frequent ragging at this site. Operations reported safety concerns with accessing the wet well at Lift Station No. 1.

3.12.3 Inspection Summary
Dudek performed a comprehensive lift station condition assessment at Lift Station No. 1. Table 50 contains observations made during the site inspection performed on February 12, 2025 and information provided by the City during the pre- and post-inspection workshops. During the September 17, 2025 planning level cost estimate review meeting, the City informed Dudek that Lift Station No. 1 is currently being designed for relocation and there are no recommendations for this site.

Table 50. Lift Station No. 1 Inspection Summary
Site Civil/ Safety & Security Condition Photo(s)
General
▪ The surrounding grade around the
dry well access hatch (within the
perimeter fence) is all dirt and
slopes towards the access hatch.
- It appears that this would cause
ponding water directly around
the access shaft creating muddy
conditions during and
immediately after a rain event.
▪ Dry well access does not have any
type of safety post to assist with
safe access onto and off the
ladder.
▪ Site fencing and dry well hatch
were locked at the time of the
inspection.

Fair/Good
Figure 197: Lift Station No. 1 Facility Site
Figure 198: Lift Station No. 1 Dry Well Access

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 152 OCTOBER 2025
Mechanical Condition Photo(s)
Pumps
▪ Self-priming pumps appear to be in
good condition.
- Moderate corrosion was
observed at Pump 3 base.
- Pumps are belt driven. Belts are
protected by belt guards.

Fair
Figure 199: Lift Station No. 1 Self-Priming Pump and Motors

Piping and Valves
▪ Ductile iron discharge piping and
valves were observed to be in fair
to good condition.
- Discharge piping and valves are
located within the below grade
dry well.
- Dust and debris covered
majority of piping and inhibited
Dudek’s ability to inspect.
▪ No bypass connection observed.
▪ No piping or valve issues reported
by Operations.

Fair/Good
Figure 200: Lift Station No. 1 Piping and Valves

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 153 OCTOBER 2025
Structural Condition Photo(s)
Wet Well
▪ Wet well access is within West
McCabe Road. Accessing the wet
well is a safety concern due to the
high traffic seen on West McCabe.
▪ The manhole riser of the wet well
has a brick stretcher course. The
mortar between the bricks has
eroded away and some of the
bricks appear to be loose and have
shifted out of place. One of the
bricks can fall and damage the
ultrasonic level sensor. In addition,
the missing brick can jeopardize
the structural integrity of the
manhole grade ring.
▪ The ultrasonic level sensor is being
held in place by a makeshift
support using a pipe with a wrench
attached to it as well as some twine
to position it towards the center of
the wet well.
▪ The overall condition of the
manhole is poor, and the interior
concrete appears to be moderately
to severely corroded in many areas
with significant loss of concrete
surface profile. There appears to be
significant corrosion on the pump
suction elbows within the wet well
based on a portion of one of the
elbows that is not covered in buildup.

Dry Well
▪ Forced Air Ventilation supply fan in
the drywell is supplied power from
an extension cord that is wirenutted to the fan leads in open air. This installation is not to
National Electrical Code
requirements and is a safety
hazard. The fan appears to have
an on/off switch located at the top
of the drywell shaft.
- Ground water leak observed at
blower bracket bolt hole within
dry well.

Poor
Figure 201: Lift Station No. 1 Wet Well Riser
Figure 202: Lift Station No. 1 Wet Well Structure and Suction Elbow

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 154 OCTOBER 2025
▪ Operations requested better
lighting to be installed within Dry
Well.
▪ Dry well structure was observed to
be in good condition.
- Dry well had significant dust and
debris build up within the
structure.
- Internal diameter was measured
to be 89-inches.

Electrical & Instrumentation Condition Photo(s)
▪ The electrical assessment is
limited, as the drywell is a confined
space entry—the electrical engineer
did not enter the drywell and
performed the assessment based
on photos by others.
▪ The electrical equipment, including
the pump control panel appeared
to be beyond its useful life
expectancy.
▪ The conduits entering the drywell
shaft were separating from the LBs
(conduit body), probably due to
ground settling. It appeared that a
repair was attempted with duct
tape and paint to seal the area, but
the duct tape was deteriorating due
to being exposed to the
elements. It is likely that water can
get into the broken conduit area
and into the conduit during a rain
event.
▪ There is a missing cover on an LB
inside the drywell shaft at the top
that needs to be installed. Missing
covers are a safety hazard and
code violation.
▪ A conduit LB inside the drywell
shaft at the top was broken with
wires visible and needs to be
replaced.
▪ Dudek could not identify where the
conduits for the ultrasonic sensor
and float switches from the wet well
enter the drywell, so we could not
determine if a sealing fitting is
installed on each conduit as it
enters the drywell.

Poor
Figure 203: Lift Station No. 1 Broken Conduits Due to
Ground Settling (2 Photos)
Figure 204: Lift Station No. 1 Broken Conduit at LB and LB with Missing Cover

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 155 OCTOBER 2025
▪ The air supply fan in the drywell is
supplied power from an extension
cord that is wire-nutted to the fan
leads in open air. This installation
is not to code and is a safety
hazard. The fan appeared to have
an on/off switch located at the top
of the drywell shaft.
▪ There is a small hole in the cover of
the control panel that should be
plugged with a hole plug to prevent
dust from entering the panel.
▪ The interior of the pump control
panel was full of dust, most likely
made worse from the hole on the
panel cover.
▪ The ultrasonic level sensor
appeared to be held in place by a
makeshift support using a pipe with
a wrench attached to it as well as
some twine to position it towards
the center of the wet well.
▪ The interior of the enclosure on the
power pole that has a disconnect
switch inside it—the enclosure and
the disconnect need to be cleaned
out to remove cobwebs, dust and
dirt. Dust, dirt and cobwebs can
provide a path for electricity that
can cause a short circuit fault. We
observed this inside the enclosure,
but did not open the live disconnect
switch.
▪ There was a conduit that routes up
the power pole to the red beacon
light that appeared to be taped
significantly at its 90-degree
bend. We presume that there is
conduit damage and separation
here that needs to be replaced.
▪ City staff indicated that the pumps
start and stop based on signals
from the level transmitter.
▪ Lift Station I/O appeared to be
transmitted off site using a Mission
Communications Cellular Wireless
RTU.
▪ Per staff, the high-level float switch
signal is transmitted via an AT&T
phone line.

Figure 205: Lift Station No. 1 Exposed Fan Wiring and Wire Terminations in Drywell
Figure 206: Lift Station No. 1 Utility Meter, Main Disconnect, and Conduits on Utility Pole

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 156 OCTOBER 2025
▪ No arc flash stickers were observed
on the electrical equipment.
▪ No standby power generator or
portable generator connection was
observed.
▪ No intrusion switches were
observed on site.
▪ No lift station discharge flowmeter
was observed.

Climate Control Vulnerability Condition Photo(s)
Flooding
▪ The surrounding grade around the
dry well access hatch (within the
perimeter fence) is all dirt and
slopes towards the access hatch.
- It appears that this would cause
ponding water directly around the
access shaft creating muddy
conditions during and
immediately after a rain event.

Electrical Outages
▪ No standby power generator or
portable generator connection was
observed.

Extreme Heat
▪ Air cooling / temperature control not
observed inside electrical
enclosures.

Poor

3.12.4 Hydraulic Assessment
The Lift Station No. 1 hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 4.2 times per hour on average with a maximum of 16 starts per hour. Pump #2 starts approximately 4.2 times per hour on average with a maximum of 19 starts per hour.

Both pumps have a similar average number of starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 5 HP, 4-pole (1725 rpm) motor should have a maximum number of 16.3 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed instances where Pump #2’s starts per hour has exceeded the NEMA recommended starts per hour. This indicates that the existing operational set points may need to be adjusted to reduce the number of starts per hour. Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 100 minutes of run time per day (1,534 total hours) while pump #2 averages approximately 91 minutes of run time per day (1,389 total hours). This data indicates that the pumps run times are comparable.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 157 OCTOBER 2025
A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Lift Station No. 1 force main is a 6” PVC pipe installed in 1975. The condition of the force main is assumed to be poor due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. Lift Station No. 1 is a duplex lift station that is assumed to operate in a duty/standby configuration. With one pump in operation, the flow velocity through this existing 6” force main is estimated at approximately 4.5 ft/sec which is in accordance with HI standards.

3.12.5 Recommended Improvements
Since Lift Station No. 1 is currently being designed for replacement and relocation, there are no recommendations for this site.

3.13 Buena Vista Lift Station

3.13.1 Location and Layout
The Buena Vista Lift Station is to the southeast of the intersection of Imperial Avenue and Manuel Ortiz Avenue.

The lift station is a self-priming duplex station with lift up fiberglass enclosure located within a block wall site. A fenced gate along the frontage of imperial avenue provides access to the site. Parking can be found directly to the west of the facility between Imperial Avenue and the lift station.

Figure 207: Buena Vista Lift Station Location

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 158 OCTOBER 2025

3.13.2 System Characteristics

3.13.2.1 Pump Station
A summary of the pumping units for Buena Vista LS is provided on Table 51, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 52.

Table 51. Buena Vista Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Unknown Unknown
Pump Type Self Priming Self Priming
Pump Mount N/A
Design Capacity 369 gpm @ 27’ TDH
Motor, hp 7.5
Motor Operation Constant Speed
Speed, rpm 1750
Discharge Diameter, inches 4
Year Installed 2006
Figure 208: Buena Vista Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 159 OCTOBER 2025
Table 52. Buena Vista Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete
Diameter, feet 8
Depth, feet 22
Floor Elevation, feet -45.5
Influent Sewer Invert, feet -39.5
Cover/Hatch Type 24” Manhole
Bypass Assembly
Valve Location Above grade fiberglass enclosure
Bypass Connection Yes
Force Main
Diameter, inches 8
Length, feet 132
Material PVC

3.13.2.2 Operations and Maintenance History
There were no operational concerns reported at this facility.

3.13.3 Inspection Summary
Dudek performed a wet well assessment for the Buena Vista Lift Station. Table 53 contains observations made during the February 13, 2025 wet well condition assessment and information provided by the City during the preand post-inspection workshops.

Although a comprehensive inspection was not performed at Buena Vista LS, it is assumed that the facility follows the trends observed at other facilities including electrical code violations, missing arc flash studies and warning labels, absence of emergency generators or receptacles, and lack of bypass pumping connections.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 160 OCTOBER 2025
Table 53. Buena Vista Lift Station Inspection Summary
Structural Condition Photo(s)
Wet Well
▪ Manhole lid and ring were observed to be
moderate to severely corroded.
▪ PVC suction and discharge piping are in good
condition.
▪ Liner beginning to fail at discharge line wet
well penetration.
▪ Flexible conduits exposed to the outdoors
have completely failed.
▪ There are no conduit seal offs installed on
conduits leaving the wet well, which allows
hazardous gases into the electrical
equipment and enclosure.
▪ The wet well manhole cover and level sensor
penetration are right up against the green
enclosure and it is assumed that the green
enclosure is not sealed to keep gases out.

This would require classifying the green
enclosure area as a hazardous location and
relocating all electrical and control
equipment out of the green enclosure and
away from the wet well per NFPA 820.
▪ The location of the utility service meter
pedestal compared to the green enclosure
location should be reviewed to ensure
compliance with NFPA 820.
▪ Force main bypass connection located in the
street.

Good
Figure 209: Buena Vista Lift Station Wet Well

3.13.4 Hydraulic Assessment
The Buena Vista Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 3.4 times per hour on average with a maximum of 11 starts per hour. Pump #2 starts approximately 3.8 times per hour on average with a maximum of 12 starts per hour. Both pumps have a similar average number of starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 7.5 HP, 4-pole (1750 rpm) motor Figure 210: Buena Vista Lift Station Wet Well Access

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 161 OCTOBER 2025
should have a maximum number of 13.9 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed that both pumps are in compliance with the NEMA recommended number of starts per hour.

Pump #1 averages 161 minutes of run time per day (2,455 total hours) while pump #2 averages approximately 169 minutes of run time per day (2,570 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Legacy Lift Station force main is a 8” PVC pipe installed in 2006. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. Buena Vista Lift Station is a duplex lift station that is assumed to operate in a duty/standby configuration.

With one pump in operation, the flow velocity through this existing 8” force main is estimated at approximately 2.4 ft/sec which is in accordance with HI standards.

3.13.5 Recommended Improvements
Recommended improvements were developed for Buena Vista LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 54.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 162 OCTOBER 2025
Table 54. East Side Lift Station Recommended Improvements Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/ Risk
Associated
Project (Term)
EI&C Install Intrusion
Switches
Intrusion switches are not currently
installed on the electrical
equipment, generator enclosure,
SCADA equipment, MCC enclosure,
and dry well hatch. It is
recommended to install intrusion
switches for SCADA notification to
prevent unauthorized access and
tampering of lift station equipment.

Safety Risk/
Security
Risk
Buena Vista
Lift Station
Rehabilitation
(Mid-term)
Structural
Replace Wet
Well Access
Cover
The existing wet well access
manhole frame and cover were
observed to be moderately to
severely corroded introducing a
safety risk for operations. It is
recommended to replace the wet
well access cover with new hatches
that are equipped with integrated
fall protection, slam lock, and lift
assist. Alternatively, a composite
manhole cover can be retrofitted
around the existing access cover
frame to mitigate the immediate
safety concern.

Injury Risk/
Operational
Failure
Buena Vista
Lift Station
Rehabilitation
(Mid-term)
Structural Wet Well Liner
Spot Repairs
The wet well liner is beginning to fail
at discharge line wet well
penetration.

Concrete
Degradation
Buena Vista
Lift Station
Rehabilitation
(Mid-term)

3.14 East Side Lift Station

3.14.1 Location
The East Side Lift Station is located to the southeast of the intersection of North 3rd Street and West Commercial Avenue. The lift station is a large wet well facility with an electrical building and a valve and metering vault within a fenced site. Access to this lift station is a gated fence on the south side of West Commercial Avenue. There is parking within the facility perimeter.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 163 OCTOBER 2025
Figure 212: East Side Lift Station Layour
Figure 211: East Side Lift Station Location

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 164 OCTOBER 2025

3.14.2 System Characteristics

3.14.2.1 Pump Station
A summary of the pumping units for East Side LS is provided on Table 55, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed. Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 56.

Table 55. East Side Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Vaughan SE6U3 Vaughan SE6U3
Pump Type Dry well Dry well
Pump Mount N/A
Design Capacity 1132 gpm @ 216’ TDH
Motor, hp 125
Motor Operation Constant Speed or VFD
Speed, rpm unknown
Discharge Diameter, inches 4
Year Installed 1913. Lift Station replaced in 2007.

Table 56. East Side Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Lined precast concrete
Diameter, feet 10
Depth, feet 27.4
Floor Elevation, feet -26.9
Influent Sewer Invert, feet -19.6
Cover/Hatch Type (2) 48” x 48” hatches
Dry Well Size, feet 35.33 x 20
Valve Vault
Dimensions, feet 6 x 8
Material Precast concrete
Depth, feet 4.2
Cover/Hatch Type 8’ x 6’ Double leaf aluminum hatch
Bypass Assembly
Valve Location N/A
Bypass Connection None
Force Main
Diameter, inches 10
Length, feet 68
Material PVC

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 165 OCTOBER 2025

3.14.2.2 Operations and Maintenance History
There were no operational concerns reported at this facility.

3.14.3 Inspection Summary
Dudek performed a wet well assessment for the East Side Lift Station. Table 57 contains observations made during the February 13, 2025 wet well condition assessment and information provided by the City during the pre- and post-inspection workshops.

Although a comprehensive inspection was not performed at East Side LS, it is assumed that the facility follows the trends observed at other facilities including electrical code violations, missing arc flash studies and warning labels, absence of emergency generators or receptacles, and lack of bypass pumping connections.

Table 57. East Side Lift Station Inspection Summary
Structural Condition Photo(s)
Wet Well
▪ Liner beginning to fail at liner termination
and various points throughout the wet well.

Several holes and bulging observed.
- Unable to determine concrete condition
behind liner.
▪ Ductile iron suction piping fittings are
observed to be moderately corroded.
- Significant corrosion at the flanged
interface between PVC and ductile iron
piping.
▪ Ultrasonic pump control. No high water
floats at this site.
▪ Integral fall protection observed at the wet
well access hatch and is in good condition.
- Protection grating coating has begun
delaminating and grating has minor
corrosion.
- The hatches and framing were observed
to be in excellent condition.
▪ Submersible pumps were not pulled for
assessment during field inspections.

Good
Figure 213: East Side Lift Station Wet Well

Figure 214: East Side Lift Station Wet Well Access Hatch

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 166 OCTOBER 2025

3.14.4 Hydraulic Assessment
The East Side Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 2.1 times per hour on average with a maximum of 10 starts per hour. Pump #2 starts approximately 2.0 times per hour on average with a maximum of 28 starts per hour. Both pumps have a similar average number of starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 15 HP, 6-pole (1160 rpm) motor should have a maximum number of 12.1 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed instances where Pump #2’s starts per hour has exceeded the NEMA recommended starts per hour. This indicates that the existing operational set points may need to be adjusted to reduce the number of starts per hour.

Note that newer motor models are capable of exceeding NEMAs recommended maximum starts per hour and therefore acceptance varies per motor manufacturer.

Pump #1 averages 160 minutes of run time per day (2,439 total hours) while pump #2 averages approximately 163 minutes of run time per day (2,480 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing East Side Lift Station force main is a 10” PVC pipe installed in 2007. The condition of the force main is assumed to be good due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. East Side Lift station is a duplex lift station that is assumed to operate in a duty/standby configuration.

With one pump in operation, the flow velocity through this existing 10” force main is estimated at approximately

4.1 ft/sec which is in accordance with HI standards.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 167 OCTOBER 2025

3.14.5 Recommended Improvements
Recommended improvements were developed for East Side LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 58.

Table 58. East Side Lift Station Recommended Improvements Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/Risk
Associated
Project (Term)
E&IC/
Mechanical
Install Backup
Level Element in
Wet Well
This lift station is not equipped
with backup mechanical floats. It
is recommended to install a
secondary level element in the
event the existing ultrasonic level
transducer fail.

Increased
SSO
Potential
East Side Lift
Station
Rehabilitation
(Mid-term)
Mechanical
Replace Existing
Suction Piping
within Wet Well
Ductile iron suction piping fittings
are observed to be moderately
corroded. Significant corrosion at
the flanged interface between PVC
and ductile iron piping.

Operational
Failure
East Side Lift
Station
Rehabilitation
(Mid-term)
Mechanical
Install Lift
Station Bypass
Connection
There is no existing bypass
connection for this lift station. It is
recommended to install a force
main bypass connection in the
event of a lift station failure.

Increased
SSO
Potential
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Near-term)
Structural Replace Wet
Well Liner
Several holes and signs of liner
separating from concrete were
observed in the existing wet well.

Operational
Failure
East Side Lift
Station
Rehabilitation
(Mid-term)

3.15 Heil & Dogwood Lift Station

3.15.1 Location
The Heil & Dogwood Lift Station is located to the northeast of the intersection of South Dogwood Road and East Heil Avenue. The lift station is a large wet well facility with an electrical building and a valve and metering vault within a fenced site. Parking can be found in the dirt parking lot to the north of the lift station.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 168 OCTOBER 2025

3.15.2 System Characteristics

3.15.2.1 Pump Station
A summary of the pumping units for Heil & Dogwood LS is provided on Table 59, which includes the number of pumps, pump model, pump type, design capacity, motor size, speed, discharge diameter, and year installed.

Similarly, all onsite structures (e.g., wet well, dry well) and force main are summarized on Table 60.

Figure 215: Heil & Dogwood Lift Station Location
Figure 216: Heil & Dogwood Lift Station Layout

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 169 OCTOBER 2025
Table 59. Heil & Dogwood Lift Station Pumping Units
Pump Characteristic
Pump No.

Pump 1 Pump 2
Pump Model Gorman Rupp T4A3-B Gorman Rupp T4A3-B
Pump Type Self Priming Self Priming
Pump Mount N/A
Design Capacity 250 gpm @ 25’ TDH
Motor, hp 5
Motor Operation Constant Speed
Speed, rpm 1050
Discharge Diameter, inches 4
Year Installed 1998
Table 60. Heil & Dogwood Lift Station Structures and Force Main Characteristics Structure Characteristic Description
Wet Well
Material Precast concrete
Diameter, feet 5.5
Depth, feet 20.5
Floor Elevation, feet -65.5
Influent Sewer Invert, feet -59.0
Cover/Hatch Type 24” Manhole
Bypass Assembly
Valve Location Above grade fiberglass enclosure
Bypass Connection Yes
Force Main
Diameter, inches 6
Length, feet 174
Material PVC

3.15.2.2 Operations and Maintenance History
There were no operational concerns reported at this facility.

3.15.3 Inspection Summary
Dudek performed a wet well assessment for the Heil & Dogwood Lift Station. Table 61 contains observations made during the February 13, 2025 wet well condition assessment and information provided by the City during the preand post-inspection workshops.

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 170 OCTOBER 2025
Although a comprehensive inspection was not performed at Heil & Dogwood LS, it is assumed that the facility follows the trends observed at other facilities including electrical code violations, missing arc flash studies and warning labels, absence of emergency generators or receptacles, and lack of bypass pumping connections.

Table 61. Heil & Dogwood Lift Station Inspection Summary Structural Condition Photo(s)
Wet Well
▪ Wet well wall concrete is in good condition.
- Spalling observed at penetrations.
- Ductile iron vent top slab penetration is
severely corroded.
▪ Wet well top slab is spalling and sections of
concrete may fall and damage pumps.
- Loss of concrete compromises top slab
integrity is a safety concern
▪ Piping within wet well is severely corroded,
rusted, and has significant structural
deficiencies observed. Potential for
catastrophic failure.
▪ Wet well access manhole and manhole ring
are moderately corroded.
- No integral fall protection observed at the
wet well access manhole.
▪ Force main bypass connection located in the
street.
▪ Operations reported that this site
experiences strong oil odors occasionally.
- This lift station is located in an industrial
zone which may be the source of this
odor.

Fair
Figure 217: Heil and Dogwood Lift Station Wet Well

3.15.4 Hydraulic Assessment
The Heil & Dogwood Lift Station hydraulic assessment is based on pump start and run time data recorded between June 2022 and December 2024. Additionally, the assessment will determine if the approximated force main flow velocity is in accordance with HI standards. Pump #1 starts approximately 0.3 times per hour on average with a maximum of 11 starts per hour. Pump #2 starts approximately 0.3 times per hour on average with a maximum of 5 starts per hour. Both pumps have a similar average number of starts per hour. Based on NEMA’s recommendations for the maximum allowable number of motor starts per hour, a 5 HP, 6-pole (1050 rpm) motor should have a maximum number of 18.4 motor starts per hour. Based on the provided SCADA data that was reviewed, we observed that both pumps are in compliance with NEMA’s recommended number of starts per hour.

Figure 218: Heil and Dogwood Lift Station
Wet Well Access

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 171 OCTOBER 2025
Pump #1 averages 31.0 minutes of run time per day (472 total hours) while pump #2 averages approximately 24.1 minutes of run time per day (368 total hours). This data indicates that the pumps run times are comparable.

A hydraulic evaluation of the existing force main was conducted to determine if the approximated force main flow velocity is in accordance with HI standards. The HI standards for force main velocity include a recommended range of 2 to 8 ft/s for standard wastewater applications. A minimum velocity of 2 ft/s is generally recommended to keep solids in suspension.

The existing Heil & Dogwood Lift Station force main is a 6” PVC pipe installed in 1993. The force main condition is assumed to be fair due to the age of the force main. The industry standard useful life of PVC is approximately 50 years. Heil & Dogwood Lift Station is a duplex lift station that is assumed to operate in a duty/standby configuration.

With one pump in operation, the flow velocity through this existing 6” force main is estimated at approximately 2.8 ft/sec which is in accordance with HI standards.

3.15.5 Recommended Improvements
Recommended improvements were developed for Heil & Dogwood LS based on the findings from the lift station inspection and hydraulic assessment. A summary of the recommended improvements is provided in Table 62.

Table 62. Heil & Dogwood Lift Station Recommended Improvements Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/ Risk
Associated
Project
(Term)
Mechanical
Replace
Existing Piping
within Wet
Well
Piping within wet well is severely corroded,
rusted, and has significant structural
deficiencies observed. Potential for
catastrophic failure.

Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 1
(Nearterm)
Structural
Install Wet
Well Liner
The wet well was observed to have no liner
protecting the concrete from the corrosive
environment within the wet well.

Concrete
Degradation
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 2
(Nearterm)
Structural
Replace Wet
Well Top Slab
Wet well top slab is spalling and sections of
concrete may fall and damage pumps. Loss
of concrete compromises top slab integrity
is a safety concern. Ductile iron vent top
slab penetration is severely corroded.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 2

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 172 OCTOBER 2025
Asset
Discipline
Recommended
Improvement
Description
Justification
Type of
Issue/ Risk
Associated
Project
(Term)
(Nearterm)
Structural
Replace Wet
Well Access
Cover
The existing wet well access manhole
frame and cover were observed to be
moderately to severely corroded
introducing a safety risk for operations.

It is recommended to replace the wet
well access cover with new hatches that
are equipped with integrated fall
protection, slam lock, and lift assist.

Alternatively, a composite manhole
cover can be retrofitted around the
existing access cover frame to mitigate
the immediate safety concern.

Injury Risk/
Operational
Failure
Structures,
Hatches /
Doors and
Bypass
Connection
Program –
Phase 2
(Nearterm)

CITY OF EL CENTRO SEWER LIFT STATION CONDITION ASSESSMENT TECHNICAL MEMORANDUM 16707 173 OCTOBER 2025
4 Recommended Improvement Projects
A summary of the scheduled improvements and operational changes, and recommended lift station capital improvement projects is provided in Section 4.

4.1 Scheduled Lift Station Improvements and
Operational Changes
The City identified several scheduled or ongoing improvements and operational changes that will be completed within the next two years. Accordingly, these improvements have been excluded from the Lift Station CIP to avoid redundant recommendations. The ongoing improvements, scheduled improvements, and operational changes are summarized in Table 63.

Table 63. Scheduled Lift Station Improvements and Operational Changes Lift Station Site Type Description
Estimated
Timeline for
Completion
Southern Lift
Station (New)
Ongoing
Improvement
The lift station is under construction and is
intended to replace three of the City’s existing
lift stations
FY 2025
3rd & Ross Lift
Station
Scheduled
Improvement The wet well is scheduled to be rehabilitation FY 2025 Lift Station No. 1 Scheduled
Improvement Full lift station replacement and relocation FY 2026 Countryside Lift
Station
Operational
Change The lift station is planned for decommission FY 2025

4.2 General Recommended Improvements
Listed below are several general improvements that are recommended to be implemented across nearly all lift stations:
• Replacement of access hatches, covers, and doors or doorways • Implement improvements to conform to the requirements of NFPA 820 and NEC 500 • Perform third-party testing on electrical equipment and breakers • Improve cellular connection at each lift station
• All ultrasonic level elements within wet wells shall be properly mounted - At majority of lift station sites, ultrasonic level sensors were hung by the manufacturer’s cable which can cause strain and premature cable failure