Lift station backup options

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






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



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

[email protected]

Engineering

Lift station backup options