Hand dug well under construction (C) A Starkman D FriedmanHand Dug Water Wells: Home Page
How to dig, install, maintain & use hand excavated drinking water wells
     


InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.

Hand dug wells: their properties, construction & sanitation.

This article offers advice for hand dug water wells and the sanitation and maintenance concerns with this water supply type. We provide advice about what to do when things go wrong, how to inspect hand dug wells for safety, safe practices for actually digging a well, and how to address hand dug well sanitation

. In our guide to hand dug wells we discuss how a hand dug well is constructed, maintained, and kept sanitary or "safe to drink".

Green links show where you are. © Copyright 2015 InspectApedia.com, All Rights Reserved.

Characteristics of hand dug wells, their construction, use, sanitation

Photograph of a water pressure booster pump and tank system

The world wide popularity of hand dug wells is accounted for by the ease of construction without specialized equipment, the simplicity of water raising equipment (a bucket on a rope has worked for thousands of years), and the ability of the Dug well to hold a large volume of water in storage for times of peak demand.

[Click to enlarge any image]

Hand Dug Wells are usually quite shallow - typically less than 25 feet deep.

  • The volume of water on hand (the well's static head) in a hand dug well depends not on the well's overall depth, but the depth and diameter of the column of water in the well when it is at rest and fully recovered from any draw-down. If you are not sure how to calculate how much water is in your well, we give the formula and some examples
    at Static Head of Water in the Well.
  • The amount of water you can get out of a hand dug well depends on its standby volume or static head, and the rate at which water flows into it -
    See WELL FLOW RATE.
    Typically, if your dug well has less than a meter of water in it at the most dry season, it is unlikely to be adequate.

Photograph of a dug well interior
  • The deepest hand dug well we could find is the 1285 ft. deep Woodingdean Well begun in 1858 and completed in 1862 in Woodingdean, a suburb of Brighton and Howe, East Sussex, England. More commonly hand dug water wells range from about fifteen feet (3 meters) in depth, to a practical depth of around 100 feet (30 meters) though 200 foot deep hand dug wells certainly exist.
  • The widest hand dug well - well we're not sure as sources conflict, but The Big Well in Greensburg Kansas is 109 feet in diameter (and 33 feet deep) may be the widest.

Watch out: digging a well by hand is quite dangerous, risking collapse on and death to the excavators. Also in very deep wells there may be air quality safety hazards. [2]

 


Digging & Using Hand Dug Drinking Water Wells

Photo of a hand dug well and hand well pump

Dug wells are usually constructed during dry weather when the water level is at its lowest, both for safety (less likely wet soils cause well collapse) and to determine the necessary depth of the Dug well to obtain adequate water supply.

Details about how to dig and construct a hand dug well such as the Oaxaca hand dug well shown at left, begin at HAND DUG WELL PROCEDURE. Basics are just below.

[Click to enlarge any image]

You might see an antique hand water pump shown at left of this article, or even a rope and bucket for removing water from the well.

But don't assume this is the only way that water is being delivered from the well.

Often we find a hand dug well whose water is delivered to the building by a ONE LINE JET PUMP.


As we show in this sketch at below left, courtesy of Carson Dunlop Associates, Usually a hand dug well is less than 20 feet deep.

Hand dug well sketch (C) Carson Dunlop Associates

Dug wells have the same sanitation difficulties as springs and cisterns: they are easily contaminated by surface runoff and in some cases may have limited ability to deliver water at modern quantity and flow rates.

Hand dug wells range in depth from a few feet to as much as three meters and are used worldwide. Often the Dug-well was lined with dry-laid stone.

Dug or excavated wells are the picturesque wells we see on postcards, with an above-ground wall and a bucket lowered by rope into the well.

But dug wells continue into modern use, often with the installation of either an in-building jet pump draw water from the well into the building. We weren't sure what the little cover in our photo above was hiding - a dug well, a cistern, or a modern well casing extending above ground.

Sources for repair parts and installation instructions for hand pumps on dug wells and shallow wells are provided at our reviewers list below.

Safety warnings for hand dug-wells

Dug well safety, Foundation Connect International

The hazards of hand dug wells include poor sanitation (ground water and surface runoff easily enter the drinking water supply), and cave-ins during construction or injuries to tools dropped into the well during construction. We are particularly concerned about the safety hazards to children when a dug well does not have a child proof wall and/or cover.

At HAND DUG WELL PROCEDURE we describe all of the detailed steps in the procedure for constructing a hand-dug well with concrete well rings in Mexico. But do not begin a well digging project without advice from an expert and do not try digging a well without following these and any other recommended safety measures for well excavation:

Hand Dug Well Construction Safety Advice

The following advice is adapted from The Hand Dug Well [instruction manual, by Henk Holtslag & John deWolf, Foundation Connect International. Links to a copy of that free manual are at our references section [2].

  • Never work alone. The excavator in the bottom of the well should have a buddy at ground level above, on guard to assist if needed. While someone is working down the well there must always be someone in attendance at the top. Never leave someone unattended at the bottom of the well.
  • Signaling between well excavator and people at ground level: A system may need to be developed for signaling between people at the bottom and top of the well for lowering and raising equipment and people. Make sure everyone understands these signals and there is no miscommunication.
  • Check all ropes and hand-dug-well digging equipment every day at the start of work
  • Rope knots: When using a rope to lower or lift something from the well, knots should be made along the rope at metre intervals to stop the rope slipping through your hands;
  • Earth lifting buckets: Ensure that the handle of the bucket is firmly fixed and cannot slip off;
  • Lowering worker into the Dug well: If possible, always use a windlass to lift and lower materials. Use a windlass with two handles and therefore two people if a digger is lowered or lifted. If one of the people loses the control of his
    handle, the digger will not fall back in the well because the other still controls his side.
  • Protect edges of the top of the well opening during construction: Put a plank across the edge of the opening to the shaft, so that people and buckets can be lowered over the edge without wearing away the ground at the side and causing it to cave in;
  • Steps in well shaft sides? Cut steps into the side of the shaft to make it easier for people going up and down the well. This is only possible if the soil is strong enough to hold the weight of a person. When you doubt: do not
    make them! [When the well digging has been completed and it is being lined, a few well builders provide stepping stones (in a stone lined well) and handles, or steel rungs and handles to permit the well to be accessed by climbing if necessary. Usually people rely on a windlass and rope.]
  • Well digger head protection: Always wear a helmet in case something falls down in the well;
  • Well digger foot protection: Be careful while loosing the soil in the well with the long chisel. Don’t cute off your toes! If possible wear shoes with a metal nose protection.
  • Safety of air supply at the bottom of a hand dug well: In narrow wells more than 15 metres deep, there may be a problem having fresh air at the bottom of the well. This is very dangerous and even poison gasses may appear. Air circulation can be helped by raising and lowering leafy branches in the shaft to ‘stir up’ the air. The best way is to
    use a ventilator to get fresh air in the well. This ventilator can easily be made by a local workshop
    and exists of local available materials.
  • Handling soil & rocks dug out of the well: Heap excavated soil more than one metre from the edge of the shaft so that as the pile grows, it will not fall back down the well;
  • Hand dug well site safety: Put a fence or some sort of barrier around the digging site to stop people and animals falling in; when the well is completed it should have a child-proof surrounding fence and cover.

Additional Dug Well Safety Advice [Opinion of InspectAPedia]

Hand dug well with surrounding wall & cover (C) Daniel Friedman
  • Provide an above-ground wall around the completed well to prevent children and animals from falling into the well - a drowning hazard.

Photo at left: this looks like a hand dug well that has an above-ground protecting wall and a cover over the actual well opening (you can just see the red edges of the cover (click to enlarge). The cover should be secure against entry by children.

  • Provide a safety screen over the above-ground wall to prevent children from falling in to the well
  • Provide a child-safe heavy, secure cover at ground level for dug wells with no above-ground wall or for any below-ground well pit.

    At a Connecticut home in the U.S. our clients, whose family included small children, was worried about lead paint hazards as their foremost concern. We arrived early and had already made a note of a rotting and unsafe cover over a hand-dug well.

    The client arrived. Her seven-year-old son leapt from the family station wagon and made a beeline for the old hand pump atop the well. As he began jumping up and down, pumping the lever, we ran to him and scooped him off of the well top just before the entire rotting cover fell into the Dug well. Our view was that this was an immediate and severe safety hazard next to which the lead paint problem was less pressing.
  • Direct surface runoff away from the well and test the water frequently for potability and for other surface-borne water contaminants.


Abandoned hand dug well in Guanajuato (C) Daniel Friedman

  • Beware of hand dug well collapse hazards - do not ever enter a hand dug well unless you are properly trained and do not work there alone.
  • Test hand dug well water regularly for potability - since these wells commonly have sanitation issues.
    See WATER TESTING GUIDE
    and
    see  WATER TESTING ADVICE
  • Abandoning a hand-dug well - requires that the well be protected from someone falling into the well; a smart abandonment will also protect the dug well from being used as a refuse or chemical dump - doing so risks contaminating the aquifer and is illegal in most jurisdictions.

    Our photo (above-left) illustrates an abandoned hand-dug well in Guanajuato, Mexico. That well has been filled-in.

Sanitation Advice for Hand Dug Wells - Dug Well Contamination

Hand dug well converted to drilled well (C) Daniel FriedmanThe chemistry of water in a dug well, and its sanitation, depend on how much surface runoff is entering the well and other factors such as the well's depth. [1]

At left our photo illustrates a hand dug well that was later converted to a drilled well with a steel casing. The old well pit is functioning now as a well pit (WELL PITS). We notice that there is no protection against surface runoff entering the top of the well casing - a sanitary or water potability concern. This rural well is being used for crop watering in San Miguel de Allende.

A dug well that gave sanitary drinking water a hundred years ago may be at greater risk of contamination today as more chemicals contaminate both surface runoff and groundwater. And it's hard to keep contaminants out of a dug well.

OPINION: While 100 years ago or more surface water found in dug wells and springs was often of high quality and potable - at least in some areas of the world.

But today it is very difficult to find sanitary drinking water where surface runoff and shallow subsurface water enter the water supply such as that provided by a dug well. This is also true for other types shallow wells such as DRIVEN POINTWELLS, and even drilled wells protected by a well casing in some cases.

Shocking a hand dug well (WELL CHLORINATION & SHOCKING) to "fix" a bacteria problem in its drinking water is probably pointless.

It is almost impossible to keep a dug well sanitary - the Dug well is completely open to both surface runoff and ground water runoff.

You can shock the Dug well, but if you are not going to drill a modern sanitary well (costly), in order to assure safe potable drinking water you will probably need to install water treatment equipment to sanitize the water - after testing to see what contaminants besides bacteria (Interpreting the Level of Bacteria) are present.

See WATER TREATMENT EQUIPMENT CHOICES for some options to help assure that water from a dug well is sanitary and thus acceptable for drinking.

Hand Dug Well Construction Procedure

The links below provide the details of how to dig and construct a hand dug water well.

 

 

Continue reading at HAND DUG WELL PROCEDURE - how to construct a hand dug well or select a topic from the More Reading links shown below.

Or see EPA GUIDE to WATER QUALITY for a discussion of dug well water sanitation and potability

Suggested citation for this web page

DUG WELLS, by HAND at InspectApedia.com - online encyclopedia of building & environmental inspection, testing, diagnosis, repair, & problem prevention advice.

More Reading

Green link shows where you are in this article series.

...




Frequently Asked Questions (FAQs)

Click to Show or Hide FAQs

Ask a Question or Search InspectApedia

Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.

Search the InspectApedia website

HTML Comment Box is loading comments...

Technical Reviewers & References

Publisher's Google+ Page by Daniel Friedman

Click to Show or Hide Citations & References