The Basics of a Well

Wells are a combination of natural and mechanical systems that serve to move water from fractures or cracks in the bedrock or pore space between grains of sediment or sand in the earth into the well and from there into the house. Generally speaking, a modern well should be drilled through the loose “overburden” of top soil, sand and sediment into the bedrock below. In geology that has groundwater, water will flow from any fractures that intersect the open borehole. In wells drilled in areas where the sediment and sand are more than a hundred or two hundred feet deep, water will flow from the pores or spaces into the well. A well should have a casing that extends at least through the overburden and possibly to the bedrock or in some instances the water table depth. In bedrock a well borehole can simply be open, but in sandy soils the borehole will require a well screen liner or slotted casing to prevent the borehole from collapsing or filling with sand and silt. Well casings used to be made of steel, but these days plastic piping is becoming more common.

For the plumbing system to function properly, the recharge rate in the well would either have to equal the pumping rate or there has to be adequate storage in the system- either a storage tank or the well itself. The recharge rate or the well recovery rate is the rate that water actually flows into the well through the rock fissures. If the well cannot recharge at the same rate at which water is being removed and does not have adequate water reserves then the well, the system would suffer intermittent episodes of severe water pressure loss. The pressure tank in the basement solves this problem by serving as storage and pressure boost, so when you turn on a faucet, the water flows. The information on your wells performance can be obtained from the water well completion report on file with the department of health. The “stabilized yield” is the recharge rate.

A well can last 50 years (I know of one well that did). However, a drop or complete loss of water production from a well can sometimes occur even in relatively young wells due to a lowered water level from persistent drought, nearby development, or over-pumping of the well which can dewater the water-bearing zones. More often, the fall in well yield over time can be caused by changes in the water well itself. According to Penn State Extension these changes can include:

• Encrustation by mineral deposits 
• Bio-fouling by the growth of microorganisms 
• Physical plugging of groundwater aquifer by sediment 
• Well screen or casing corrosion 
• Pump damage 

Monitoring of a well’s performance brings everything into view, good or bad, and allows for preventive maintenance. While many wells will last decades, not all will last that long.  My well is 21 years old.  When I had the pump and pressure tank replaced a few years back, I got a reading on the static water level. It was about 16 feet lower than recorded on the well completion report. That is a bad sign for the groundwater. Nonetheless, the problems I am most likely to experience are mechanical.

How long a well lasts depends on many factors; the geology and hydrology of the region, the amount of ground cover nearby, how the well was constructed, what equipment has been installed “down hole,” and what maintenance activities have been performed to date. Over time every component of a water system will fail. My water “burped and sputtered” one morning and I decided that was my warning and replaced the pump and pressure tank and pressure switch the next spring. The well had passed what I had determined was the median life of a pump- 15 years and I preferred to schedule my pump replacement.)

As a water well ages, the rate at which water may be pumped referred to above as the well yield tends to decrease. The mechanical components and the well structure, screens and casing all age and deteriorate. Well maintenance and monitoring of the water and well’s performance is important in keeping the water flowing. A well owner must think about their well in terms of stewardship over the long term, long before your well fails.

Well casings are subject to corrosion, pitting and perforation. Iron bacteria and scale will build up in fittings and clog the pitless adaptors and pipes. A water pressure loss can result from a pump that is too small for demand, inadequate or a failing pressure tank, or a buildup of scale in the pipes. There are a number of reasons why a well might stop producing water, but basically they break down into equipment failure, depletion of the aquifer or other groundwater problems and failing well design and construction.

The essential mechanical components of a modern drilled well system are: a submersible pump, a check valve (and additional valve every 100 feet), a pitless adaptor (a fitting that makes a 90 degree turn to make the connection between the water line in the well and the horizontal pipe that runs below the frost line to the house), a well cap (sanitary sealed), electrical wiring including a control box, pressure switch, and interior water delivery system. There are additional fittings and cut-off switches for system protection, but the above are the basics. To keep the home supplied with water the system and well must remain operational.

Drilled Water Wells and the Pitless Adaptor

If you have a water well at your home, you need to understand how it works. Even if you are going to hire help managing your well and water system you need to understand it and make sure whoever you hire knows what they are doing. I am an old lady with arthritis and ripped rotator cuff. I am pretty sure I will never pull a pump again. Pulling a pump is more than a one man job. Equipment problems are the most common well problems, but it is not always the most expensive piece of equipment that is causing a problem. 

So, lets back up. There was a time when a water well was literally a hole hand dug into the ground where you just kept digging until you reached the water table, where all the spaces between the rock and dirt particles are filled with water, and water filled the bottom of the hole. In olden times a bucket was used to take the water from the well. These types of shallow wells (under a hundred feet deep) are easily contaminated from the surface and tend to dry out during droughts. In the 21st century in the United States digging a well by hand has been largely replace by automated drilling methods. Modern wells are more often drilled by a truck-mounted drill rig that was invented at the end of the 19th century and continually improved in the 20th century.

Howard Hughs, the one we all think of, who was the founder of Hughs Aircraft and the reclusive billionaire was actually Howard R. Hughs Jr. His father, Howard R. Hughes Sr. (who died when Howard Jr. was 19) along with a man named Sharp were the inventors of the two-cone rotary drill bit used for drilling for oil. This drill bit design also impacted water supply by enabling deeper drilling through rock. The Sharp-Hughes bit allowed access to more reliable and consistent water sources in areas where shallow aquifers were not available or sufficient. The first major advancement in water wells in the 20th century was the ability to drill them deeper for a more pristine and reliable water supply.

from privatewellclass.org

Most modern drilled wells are built with a submersible pump and sanitary sealed well cap so that the ground water is not exposed to potential contaminants before it reaches your home. This is accomplished by using a pitless adapter within the well. This adapter is designed to provide a sanitary seal at the point where the water line leaves the well to enter your home. The pitless adaptor attaches directly to the well  casing below the frost line and provides a watertight subsurface connection, protecting the well from frost and contamination. In older pump installations, above ground jet pumps were often used in a pit, which potentially allowed the introduction of contaminants at the surface concrete pit cover.

The essential components of a modern drilled well system are: a submersible pump, a check valve (and additional valve every 100 feet), a pitless adaptor, a well cap, electrical wiring including a control box, pressure switch, and interior water delivery system. There are additional fittings and cut-off switches for system protection, but the above are the basics. The components within the basement provide consistent water pressure at the fixtures.

both parts of the pitless adaptor put together from PITLESS ADAPTER | HHPAC

The right portion slides into the top of the left portion which is connected to the well casing

here you see the blank end of the portion that will connect to the pipe (right)

The invention of the pneumatic reciprocating piston Reverse Circulation drills, submersible pump and pitless adaptor changed everything. Wells could easily be drilled deeper and faster. Unlike older systems that required a well pit to house the connection, pitless adaptors eliminated the need for such pits, hence the name "pitless." This innovation ensures that the water remains free from surface contamination, and in 1969 (when I was a teenager) a new and improved pitless adaptor was patented and has spread widely.

The improved pitless adapter was designed to make the pump and system easier to access for maintenance and repairs. The two parts of the adaptor (stationary portion that is connected to the well casing and the movable portion that is connected to the flexible well pipe are connected by a  T-coupling and slip joint casting. This means that the parts can be easily pulled up free of its wedge engagement by using a “T” on a piec of metal pipe with threading to tie into the lug end dead head.

 

The water is spewing out of the pitless adaptor that holds the black flexible water pipe. The metal  "T" was threaded into the top of the pitless adaptor and used to pull the pump. 

Once you thread in the metal  "T", you jiggle it to break up any encrustation (it was in that well for 16 years) and then just pull the black flexible pipe up. (If its been in the well a long time, the pipe may look like its covered in rust or orange slime. That is iron bacteria that seems to eventually appear in all wells over time.)  The "T" is basically a handle that prevents the pipe and pump assembly from falling into the well. The red contraption on top of the well grips the pipe and locks it in place. It's called a quick clamp and don't try to pull a pump without one. You could end up trying to fish a pump lint out of the well. Here it is being used to hold the pipe and pitless adaptor away from the well to test the pump. 

close up of the quick clamp

The improved pitless adapter is for easy installing and eliminate most interior ledges or the like, which might collect water, foreign matter or set up rust within the casing. The improved design for the pitless adapter eliminated the need for a complicated slip joint with mating male and female element  and eliminated the need for an elbow joint. This design met all the emerging sanitary and code requirements cheaply. Always after you open a well you need to chloring shock the well. Pouring a cup of bleach into the well is not enough. 

closeup of the pitless adaptor