Post on 12-Jul-2015
How to Drag a 1960s Lift
Station Leaking & Squeaking
into the 21st Century
Presented at the Arkansas Water Environment Federation
2008 Conference in Hot Springs Arkansas April 29, 2008
David E. Mizell, P.E.
Jon A. Kremer, P.E.
Burns & McDonnell - St. Louis, MO
David Moss, P.E.
Paragould Light Water & Cable
Agenda
� Pump Station History
� Project Objectives
� Project Challenges� Project Challenges
Agenda
� Pump Station History
� Project Objectives
� Project Challenges� Project Challenges
� Design Factors
� Construction
� Lessons Learned
� Operational Experience Apr 07 – Mar 08
History, Part 1
� Built 1965
� Concrete cast-in-place
� All-Brick above grade � All-Brick above grade
� Wet well 12’ W by 8’ L by 34’ D
� Dry well 12’ W by 12’ L by 34’ D
� 3 pumps, vertical shaft, motors at surface
� Discharge out east and west walls!!
Service Area
� This Lift Station Serves:
• 4 other pump stations
• 486 acres total
• 814 homes and businesses• 814 homes and businesses
• Avg. Flow = 0.375 MGD
• Peak Flow = 1.75 MGD est
Project Objectives – 1
� Fix leaks at wall of
wet well
� Wall pipe with leaded
seal seal
� Replace intake piping
to pumps
Project Objectives – 2
� Replace old water pumps
� Replace old pump motors & pump motors & eliminate shafts
� Valves & couplings for future repairs
Project Objectives – 3
� Stop leaks at wall
discharge points
� This leak was
suspected ground suspected ground
water infiltration
� Actually was a
crack in the pipe!
Project Objectives – 4
� Convert to VFD
control
� Install pressure
transducer in wet transducer in wet
well for primary
level control
� Floats as
secondary control
Project Challenges
� Maintain Service
at all times
• Short breaks OK
� Tight cramped � Tight cramped
vertical space
View down Dry Well
Design Objectives
� Create single discharge line
• Old pumps 1 & 2 discharged out West side
• One pump 3 discharged out East side
Design Objectives
� Create single discharge line
• Old pumps 1 & 2 discharged out west side
• One pump 3 discharged out east side
� Improve reliability and redundancy� Improve reliability and redundancy
Design Objectives
� Create single discharge line
• Old pumps 1 & 2 discharge out west side
• One pump 3 discharges out east side
� Improve reliability and redundancy� Improve reliability and redundancy
� Keep Station in service during
construction
• Bypass wet well to existing 12-inch force main
• Replace 3 pumps in 2 phases
3 Replacement Pumps
One New Pump 1
� 400 gpm
� 115 feet total
dynamic head
� 8-inch suction
� 4-inch discharge
� 30 HP motor
� 1,800 rpm
� 480 V, 3 Ph
3 Replacement Pumps
New Pumps 2 & 3
� 1,000 gpm each
� 115 feet total
dynamic head
One New Pump 1
� 400 gpm
� 115 feet total
dynamic head
� 8-inch suction
� 6-inch discharge
� 50 HP motor
� 1,800 rpm
� 480 V, 3 Ph
� 8-inch suction
� 4-inch discharge
� 30 HP motor
� 1,800 rpm
� 480 V, 3 Ph
Use 3-D Design
Looking Southeast Looking South
Pre-Bypass #1 Activities
� Expose Force Main &
install tapping sleeve &
valve
� Set up bypass pumps � Set up bypass pumps
and piping
• Pump out of manhole upstream of lift station
• Feed force main through tapping sleeve & valve
During Bypass #1
� Pump out wet well
� Turn off Pump 3 & close
valves to isolate
� Remove Pump 3 & piping
Core drill into wet well for
Phase 2Phase 1
� Core drill into wet well for
new intake
� Install new suction elbow,
pipe spool & valve for
Pump 3
� Re-activate Pumps 1 & 2
P-3 P-2 P-1
After Bypass #1 Activities - 1
� Core drill North wall for new discharge pipe
� Install Pump 3 base & vibration isolatorsvibration isolators
� Install new Pump 3 & Motor
� Install new conduit, wiring, etc.
After Bypass #1 Activities - 2
� Install piping & valves to outside
� Outside: install meter vault & bypass piping vault & bypass piping & valves
� Install wet well water level transducer & redundant floats
Meter Vault
� Dismantling Coupling
� Mag. Flow Meter
� Tee
� Full Size Valve
Air release valve
� Air Release Valve
• If future emergency occurs,
remove air release valve,
install connector, bring in portable pump, and discharge at Tee into force main
� Full Size Valve
During Bypass #2
� Turn off Pumps 1 & 2,
close valves to isolate
� Pump out wet well
� Disassemble piping &
remove Pumps 1 & 2remove Pumps 1 & 2
� Core drill into wet well for
intakes 1 & 2
� Install new suction elbows, pipe, & valves
� End bypass #2
After Bypass #2
� Install Pumps 1 & 2, motors & wiring
� Install piping and valves to new discharge headerdischarge header
� Start up Pumps 1 & 2
� Demolish Old Piping Outside
Actual Construction
� Contractor did one LONG
Bypass Period
• Elec Feeds
• Two portable pumps
� Tackle all pump & piping � Tackle all pump & piping
replacements at once!
� All Core Drilling 1 mob
� Weather cooperated,
No big storms!
New Pump Station Operations
� April 2007 – March 2008
• Total Pump Cycles = 42,749 (Avg. 118/day)
•• Total Flow = 137 MG (377,000 gpd)
Pump Cycles Apr-07 to Mar-08
200
250
300
350
400
Pu
mp
Cycle
s /
Day
0
50
100
150
200
Apr-
07
May-
07
Jun-
07
Jul-
07
Aug-
07
Sep-
07
Oct-
07
Nov-
07
Dec-
07
Jan-
08
Feb-
08
Mar-
08
Date
Pu
mp
Cycle
s /
Day
Daily Flow Apr-07 to Mar-08
800
1,000
1,200
1,400
Daily F
low
(000 g
al)
0
200
400
600
Apr-
07
May-
07
Jun-
07
Jul-
07
Aug-
07
Sep-
07
Oct-
07
Nov-
07
Dec-
07
Jan-
08
Feb-
08
Mar-
08
Date
Daily F
low
(000 g
al)
Dry Day Operation 5/28/2007
800
1,000
1,200
1,400
Flo
w R
ate
(g
pm
)
0
200
400
600
0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 0:00
Time of Day
Flo
w R
ate
(g
pm
)
Flows on 5/28/07 from 6:00 to 8:00 AM
800
1,000
1,200
1,400
Flo
w R
ate
(gpm
)
0
200
400
600
6:00 6:15 6:30 6:45 7:00 7:15 7:30 7:45 8:00
Time of Day
Flo
w R
ate
(gpm
)
Wet Day Operation 11/25/07
800
1,000
1,200
1,400
Flo
w R
ate
(g
pm
)
0
200
400
600
0:00 3:00 6:00 9:00 12:00 15:00 18:00 21:00 0:00
Time of Day
Flo
w R
ate
(g
pm
)
Conclusion
� 1960s era Pump Station was an O&M nightmare
� Many ways to modernize this facility
� 3-D design was effective tool� 3-D design was effective tool
� Over-core of pipe penetrations was key
� Bypass pumping successful
� Nightmares Over!
Questions?Questions?