lift station backup options
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BACKUP POWER FOR EMERGENCY PUMPING
Brian GongolDJ Gongol & Associates, Inc.
March 14, 2017
Nebraska Rural Water ConferenceKearney, Nebraska
Here comes the rain again
If you have to pump, you need backup power
Causes of power outages
Ice storms
System overloads
Routine accidents
Thunderstorms
What happens in a thunderstorm?
I&I (or high combined flows)
You need power most when it's easiest to lose
Six power options
1. Redundant grid access
2. Fixed electric generators
3. Portable electric generators
4. Fixed engines
5. PTO
6. Portable pumps
Storage also matters
Does storage give you time to act?
We'll come back to storage later
Option #1: Redundant grid access
Ten States permits "independent substations"
Power systems very expensive to install
Independent grids, but common threats
Ice storms
High winds and hail
High temperatures
All tend to hit a broad geography
Of no help at all in case of mechanical failure
Requires switching equipment
Option #2: Fixed generators
Common practice to mount at station sites
May be interior or exterior to station
Requires transfer switching
Expensive to install
Not usually integrated with the pump station
Sizing risk: You don't want it too small
Sizing risk: You don't want to pay for too much
Often requires a large footprint
Roughly doubles this station footprint
Requires fuel storage or supply
May require spill containment
Requires regular exercise and maintenance
Operates non-stop on power failure
Creates non-stop noise
Consumes fuel
Can create heat and other byproducts
Option #3: Portable generators/gen sets
Problem: Travel can be difficult when needed
Sacrificing manpower at critical times
Can consume a lot of fuel
May require lots of shuttling or babysitting
May be useful for other applications
Can be very loud
May be time-consuming to activate
Requires routine exercise and maintenance
Requires parts, training, and service
Requires storage
Transportation considerations
How big?How heavy?
How towable?What kind of skid/wheel kit/trailer?
Fuel may go bad
Not helpful in a lightning strike
Operates continuously even when pumps don't
Not an "efficient" approachin the strict sense of the word
Option #4: Fixed engines
Double-shafted motor with a clutch
Fixed-engine backup configuration
Fixed-engine backup configuration
Fixed-engine backup configuration
Fixed-engine backup configuration
Fixed-engine backup configuration
Fixed-engine backup configuration
Fully integrated unit - no transfer switch
Can use natural gas, LP, or other fuels
Highly compact, fully secure footprint
All O&M conducted indoors; no outdoor work
Buildings can reduce noise
Can be made "neighborhood-friendly"
Single-engine or multiple-engine configs
Little or no field wiring required
Usually employs dual AC/DC controls
Battery on trickle charger supplies controls
Engine shuts down when not in use
Tamper-proof and vandalism-resistant
Should be factory-designed and tested
Only option that can be fully factory-tested
Option #5: PTO
Useful in select applications
Handy if tractors are in widespread use
May work mainly with lineshaft pumps
Option #6: Portable pumps
Simple version: Drop hoses in a hole
Better version: Built-in bypass connections
Most complex: Self-contained portable station
Consider noise abatement
Consider fuel storage
Consider fuel choice, too (gas vs diesel)
The pump will need storage, too
Some require babysitting
Some supplied with full control packages
Best if station accommodates quick activation
Least amount of total equipment required
Requires operator time and effort to start
REMEMBER:By the time you get the call,
you're probably alreadyin an alarm condition
-- and that's before travel time
May have multipurpose use
May be only option for a flooded station
Portable station, semi-permanent placement
Consider transportation issues
Carry in back of a truck?
Lift by hand?
Skid-mounted?
Trailer-mounted?
Highway trailer?
Consider cold-weather operation
Do you want to work on this in the cold?
Will a diesel engine work?
Can you get to every site in a snowstorm?
Reliability is critical: Plan around "PEAT"
Pump
Engine
Accessories
Transportation
Storage capacity also matters!
A common mistake: Under-sizing the wetwell
Wetwell capacity isn't linear with diameter
5' of storage in 6' diameter: 1,055 gallons
5' of storage in 8' diameter: 1,880 gallons
5' of storage in 10' diameter: 2,937 gallons
A larger wetwell rarely changes O&M costs
But what about the wetwell going septic?
Anti-septic solution #1: Mixers
Anti-septic solution #2: Cyclical aeration
Anti-septic solution #3: Pumping cycles
Anti-septic solution #4: Chemicals/microbes
Overflow basins/storage
Be aware of what's stored in gravity sewers
Hundreds of gallons can be hidden
May cause extraordinary pumpdown times
Also note what's stored in the force main
Not useful for emergency operations
But important to total system operation
To recap
Consider all six options:
Redundant grid access
Fixed electric generators
Portable electric generators
Fixed engines
PTO
Portable pumps
Up-front cost doesn't tell the full story -- at all
Each option has its place
Sources
Radar map of March 6, 2017 severe weather from NOAA
Map of derecho event in 2014 from NOAA:
http://www.spc.noaa.gov/misc/AbtDerechos/casepages/jun302014page.htm#
All other photos and illustrations are the original work of the author, the author's company, or Gorman-Rupp
All rights reserved; reproduction prohibited without written consent
Thanks for your attention
Contact us anytime with questions
Brian Gongol - DJ Gongol & Associates515-223-4144
brian@gongol.net
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