The Driller
  • Sign In
  • Create Account
  • Sign Out
  • My Account
  • NEWS
  • CLASSIFIEDS
  • EQUIPMENT
  • SAFETY
  • VIDEOS
  • EDUCATION
  • SOURCEBOOK
  • EVENTS
  • SUBMIT
  • ABOUT
  • SIGN UP
cart
facebook twitter linkedin youtube
  • NEWS
  • Water
  • Geothermal
  • Construction
  • Environmental
  • Mining
  • All Industry News
  • EQUIPMENT
  • Rigs & Heavy Equipment
  • Consumables
  • Pumps
  • Featured Products
  • VIDEOS
  • Newscast
  • Drill Talks
  • Ask Brock
  • Emerging Drillers
  • EDUCATION
  • Drilling Business Insights
  • Reference Desk
  • Sponsored Insights
  • EVENTS
  • Conferences & Demo Days
  • Newscast LIVE
  • SUBMIT
  • Drillers @Work
  • ABOUT
  • Contact
  • Advertise
The Driller
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
The Driller
  • NEWS
    • Water
    • Geothermal
    • Construction
    • Environmental
    • Mining
    • All Industry News
  • CLASSIFIEDS
  • EQUIPMENT
    • Rigs & Heavy Equipment
    • Consumables
    • Pumps
    • Featured Products
  • SAFETY
  • VIDEOS
    • Newscast
    • Drill Talks
    • Ask Brock
    • Emerging Drillers
  • EDUCATION
    • Drilling Business Insights
    • Reference Desk
    • Sponsored Insights
  • SOURCEBOOK
  • EVENTS
    • Conferences & Demo Days
    • Newscast LIVE
  • SUBMIT
    • Drillers @Work
  • ABOUT
    • Contact
    • Advertise
  • SIGN UP

Sizing a Well Pump

November 1, 2006
A pump should be selected to meet normal peak demand for the household. Photo courtesy of Goulds Pumps Inc.


Editor's note: This article from the Water Systems Council, while rather basic in approach for water professionals, serves as a good overview, presented in a way that many of your residential customers would find helpful to understand.

Proper sizing and selection of the components in your water well system, most notably the well pump, are essential to meet your water needs today and in the future.

Seven minutes is the average high water-use timeframe for a shower.

Role of the Well Pump

Well construction typically consists of three steps. First, the water well is drilled to meet all well construction standards in the area. Next, a trench is dug to connect the well to the house and/or other buildings. Finally, a well pump is selected that will raise water from the well and deliver it to a storage tank in the home, where it is held under pressure until needed.

Selecting or sizing the well pump is a critical step in this process, determined by the yield of the well and the needs of the household. The general rule is to never install a pump that has a greater capacity than the well.

The pump usually refers to both the pump itself and an electric motor, which, together, make up the pumping unit. The pump may be one of several types: shallow-well or deep-well, jet, submersible or reciprocating. When the pump turns on, it fills the pressure tank used for water storage.

A water softener means a pressure drop.

Gallons per Minute

A key to selecting the right size pump is to figure the gallons per minute of water required at peak periods. A pump should be selected to meet normal peak demand for the household, rather than average use. There are two common methods for sizing a residential pump system that give similar results:

Residential Capacity Based on Fixture Count - The capacity of the pump system in gallons per minute should equal the number of fixtures in the home. This must take into account all use for the kitchen, bath, appliances, outside irrigation, a pool and special fixtures, such as a hot tub. In this model, a modern home with two bathrooms (three outlets each), kitchen sink, dishwasher, washing machine, laundry tub and two outside hose outlets would require a capacity of 12 gallons per minute, based on the 12 fixtures or outlets.

Residential Capacity Based on Peak Demand - A second model, using the same fixtures and plumbing as the previous example, calculates capacity based on a seven-minute peak demand. The peak time for household water use normally is in the morning, when the family rises, or in the evening, when all are home. Seven minutes is the average high water-use timeframe for a shower or automatic washer.

Low Well Capacity

In the best and most economical water system, the needs of the household are less than the rate at which water can be drawn from the well. If the peak demand exceeds the maximum rate of water available, the pump must be sized within the well capacity and the peak demand reached through added storage capacity.

Usually, a large-size pressure tank can perform this function. In fact, a larger water storage tank can prolong the life of a pump, as it reduces the need for the pump to cycle as often. Most wear-and-tear on the well pump occurs when it stops and starts.

There are times, however, when the well capacity is so low that a two-pump system is needed. In a two-pump system, the well pump supplies water to an atmospheric storage tank. A second pump, a shallow-well unit, takes water from the atmospheric tank and discharges it into the pressure tank or directly into the system. Its operation is controlled with a pressure switch.

Adequate Water Pressure

Water pressure is the final consideration in sizing the well pump. Pressure must be sufficient to force the water through the piping system to the highest outlet and to properly operate modern appliances, continuously and when other outlets are also in use.

Most appliances, such as dishwashers and washing machines, require a pressure of at least 10 pounds per square inch (psi) at their inlet for proper operation. Lawn sprinklers usually require a minimum of 20 psi and sometimes up to 40 psi. The installation of water conditioning equipment, such as water softeners, results in a pressure drop in the system for different flow rates and must be considered in determining required pressure.

If the piping system is old and the inside diameters of the pipes are reduced due to deposits of rust or lime, the friction loss through the system will be great. Therefore, a higher-pressure setting will be required. If the pump is located a distance from the house, and particularly if it is at a lower elevation, higher pressure is required. Most modern water systems are set to operate between 30 psi to 50 psi, or between 40 psi to 60 psi.

A conservative method of determining the best pressure setting is to have a pressure of 20 psi at the inlet side of the fixture that is the highest and farthest from the pump, as measured when water is flowing through the fixture.

Select the Right Pump

Each type of well pump has advantages and limitations. Consider these factors before making a final selection:
  • Adequate capacity (gallons per minute) for present and future use.
  • Adequate pressure for present and future use and for the possibility of a lower water level in the well.
  • Cost of the pump.
  • Cost of the labor to install the pump.
  • Cost of materials to install the pump, such as piping, fittings, accessories, well pit, etc.
  • Power supply.
  • Area needed to install the pump. Is there enough space available?
  • Reliability of the pump.
  • Cost and ease of servicing the pump.
  • Cost of operating the pump, including power and parts.

ND

This article is provided through the courtesy of the Water Systems Council. The Council's Web site (www.watersystemscouncil.org) offers a wealth of public education materials.

Share This Story

Looking for a reprint of this article?
From high-res PDFs to custom plaques, order your copy today!

Recommended Content

JOIN TODAY
to unlock your recommendations.

Already have an account? Sign In

  • geotechnical drilling rig

    6 Onsite Phrases Environmental Drillers Hate

    Here are six phrases that highlight common frustrations...
    The Underground Network
    By: Jeff Garby
  • Wayne Nash

    Pipe Stuck? Common Causes and Solutions for Drillers

    If you have drilled for any length of time, sooner or...
    Opinions
    By: Wayne Nash
  • submersible pumps, water well pumps

    Selecting and Sizing Submersible Pump Cable

    This article helps pump installers and servicers decide...
    Water Wells
    By: Bob Pelikan
You must login or register in order to post a comment.

Report Abusive Comment

Subscribe For Free!
  • eNewsletters
  • Online Registration
  • Subscription Customer Service
  • Manage My Preferences

The Driller Newscast: New York Geo Talks 2025 Conference with Hands-on Driller Education

The Driller Newscast: New York Geo Talks 2025 Conference with Hands-on Driller Education

The Driller Newscast: Coiled Tubing Drilling and the Future of Geothermal

The Driller Newscast: Coiled Tubing Drilling and the Future of Geothermal

The Driller Newscast: 21st Century Drillers | Part 1 DEMAND

The Driller Newscast: 21st Century Drillers | Part 1 DEMAND

The Driller Newscast, Episode 147: Global Geothermal Collaboration at NY-GEO 2025

The Driller Newscast, Episode 147: Global Geothermal Collaboration at NY-GEO 2025

More Videos

Sponsored Content

Sponsored Content is a special paid section where industry companies provide high quality, objective, non-commercial content around topics of interest to the The Driller audience. All Sponsored Content is supplied by the advertising company and any opinions expressed in this article are those of the author and not necessarily reflect the views of The Driller or its parent company, BNP Media. Interested in participating in our Sponsored Content section? Contact your local rep!

close
  • demo of a DM450 drilling rig during a customer factory visit
    Sponsored byGeoprobe

    Built for You: Smarter Drill Rigs, Stronger Support, Bigger Opportunities

Popular Stories

MainPhotoTwoBrothers.jpg

Two Brothers' Journey Through the Drilling Industry

AI and Drought Concerns

AI’s Growing Thirst for Water and Power

demo of a DM450 drilling rig during a customer factory visit

Built for You: Smarter Drill Rigs, Stronger Support, Bigger Opportunities

The Driller Classifieds

COMPRESSORS

EAST WEST MACHINERY & DRILLING IS BUYING AND SELLING AIR COMPRESSORS, AIR BOOSTERS, AIR ENDS & PARTS
Company: East West Machinery

DRILL RIGS

LOOKING FOR LATE MODEL TOPHEADS & DRILLTECH D25'S
Company: Spikes’s Rig Sales

DRILL RIG PARTS

MEETING DRILLERS NEEDS AROUND THE WORLD
Company: East West Machinery

ELEVATORS

SEMCO INC. PIPE ELEVATORS
Company: Semco Inc.

GROUTERS

GROUTING EQUIPMENT - GROUT PUMPS & GROUT HOSE REELS
Company: Geo-Loop Inc.

PUMP HOISTS

SEMCO INC. - BASIC PUMP HOISTS
Company: Semco Inc.

WELL PACKERS

LANSAS PRODUCTS - INFLATABLE WELL PACKERS
Company: Vanderlans Lansas Products

WELL SCREENS

WELL SCREENS & SLOTTED PIPE
Company: Alloy Screen Works

Products

Water Quality Engineering: Physical / Chemical Treatment Processes

Water Quality Engineering: Physical / Chemical Treatment Processes

By carefully explaining both the underlying theory and the underlying mathematics, this text enables readers to fully grasp the fundamentals of physical and chemical treatment processes for water and wastewater.

See More Products

Subscribe to The Driller Newscast

Related Articles

  • Sizing a Residential Water System

    See More
  • Tech Topics: Sizing a Residential Water System - Part 1: Flow

    See More
  • Tech Topics: Sizing a Residential Water System - Part 1: Flow

    See More
×

Dig deeper into the drilling and water supply industry!

Build your knowledge with The Driller, covering the people, equipment and technologies across drilling markets.

SIGN UP NOW
  • RESOURCES
    • Advertise
    • Contact Us
    • Directories
    • Store
    • Want More
    • Classifieds
  • SIGN UP TODAY
    • Create Account
    • eNewsletters
    • Customer Service
    • Manage Preferences
  • SERVICES
    • Marketing Services
    • Reprints
    • Market Research
    • List Rental
    • Survey/Respondent Access
  • STAY CONNECTED
    • LinkedIn
    • Facebook
    • YouTube
    • X (Twitter)
  • PRIVACY
    • PRIVACY POLICY
    • TERMS & CONDITIONS
    • DO NOT SELL MY PERSONAL INFORMATION
    • PRIVACY REQUEST
    • ACCESSIBILITY

Copyright ©2025. All Rights Reserved BNP Media.

Design, CMS, Hosting & Web Development :: ePublishing

The Driller
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
The Driller
  • NEWS
    • Water
    • Geothermal
    • Construction
    • Environmental
    • Mining
    • All Industry News
  • CLASSIFIEDS
  • EQUIPMENT
    • Rigs & Heavy Equipment
    • Consumables
    • Pumps
    • Featured Products
  • SAFETY
  • VIDEOS
    • Newscast
    • Drill Talks
    • Ask Brock
    • Emerging Drillers
  • EDUCATION
    • Drilling Business Insights
    • Reference Desk
    • Sponsored Insights
  • SOURCEBOOK
  • EVENTS
    • Conferences & Demo Days
    • Newscast LIVE
  • SUBMIT
    • Drillers @Work
  • ABOUT
    • Contact
    • Advertise
  • SIGN UP