Well Water System

Well Water System photos: P 57-P 64, P 230

The main components of a well water system consist of a well pump, the water lines, the pressure gauge and the water storage tank. The basic operation of a well system is as follows:

  1. The well pump sends water up from the well through the water lines. The water builds up in the water storage tank. When the tank pressure gauge reaches its high setting, the pressure switch turns the well pump off. Water then sits in the water storage tank, similar to a water heater tank.

  2. When a faucet is turned on, the water is drawn from the storage tank only, and not the well. The water pressure in the storage tank begins to drop as the water continues to run from the faucet. When the pressure gauge drops a few psi, it switches on the well pump to replenish the water supply in the water storage tank. This is needed to keep the tank near full capacity or to keep up with the water being drawn from the faucets.

  3. The purpose of the water storage tank is to hold enough water so the well pump doesn't have to turn on every time someone turns on a faucet. If the storage tank is faulty or isn't large enough, then the well pump will turn on just about every time someone turns on a faucet. This is called short cycling and will lead to premature failure of the well pump because it's operating too often.

There are three types of well pumps: suction pumps, jet pumps, and submersible pumps. The type of well pump installed will be based upon the depth of the well.

  • Suction pumps are only used for very shallow wells that are 25 feet deep or less. A suction pump is installed next to the well water storage tank. These pumps only have one water pipe in the well shaft. A vacuum must be maintained in the pipes for the pump to lift the water from the well. Suction pumps are inefficient because a perfect vacuum in the well pipes can only lift water about 25 feet. If there are any leaks or debris in the pipe, the vacuum pressure is reduced. As a result, the water cannot be lifted as high. Suction pumps have a life expectancy of about 15 years.

  • Jet pumps can be used for wells that are 120 feet deep or less. Like a suction pump, a jet pump is installed next to the well water storage tank. These pumps have two water pipes in the well shaft. One pipe is the larger suction line. The other pipe forces water down the well to push more water back up the suction pipe. About 5 gallons of water are pumped down the well and 8 gallons of water are pushed up the larger suction pipe. This provides an overall 3 gallons of water per minute and isn't efficient. Jet pumps use much more energy because they push water down the well, while trying to lift more water out of the well shaft. Moreover, as with suction pumps, jet pumps cannot have any leaks or debris in the pipes. This would cut down the efficiency even further by fouling the vacuum needed for this system. Jet pumps are generally more expensive to repair. Jet pumps have a life expectancy of about 15 years.

  • Submersible pumps can be used for the deepest wells. Unlike the other pipes, submersible pumps are installed completely inside the well shaft. As a result, you won't see any well pump parts during your inspection. Since the pump parts are not in the house, submersibles are the quietest type of pumps. Submersible pumps are the most efficient types to use. They have a life expectancy of about 10 years.


Try to get as much information as you can about the well from the owner or Realtor. Use the preinspection questions that I mentioned earlier for a guideline. And don't be afraid to ask any other questions for further information. There will be many times that the owner or Realtor won't be able to tell you very much about the well system. Unfortunately, this is often the case. Don't be surprised if the answers you get don't seem to be the truth from the results of the well test.

Real Estate Expert Investing Advice FSBO Homeowners House Buyers Sellers Realtors Agents Brokers I did an inspection once and the seller of the house was an eye doctor who said the well was always running fine. This eye doctor told the client and me that he and his family had never had problems with water pressure. After testing the well for about 10 minutes, all the faucets ran dry and there was almost no water coming out. This honest eye doctor stated that he had never had that happen before. I told my client to call a well contractor to have the well checked out. The client found a well contractor that told him he didn't even need to go out to the house to find the problem. This contractor said that he had evaluated that well for two previous potential buyers of the home. Both other buyers didn't buy the house because the well needed to be either redrilled deeper or moved completely because it constantly ran dry. (So much for the integrity of that eye doctor. Someone ought to tell him that you can go blind from telling too many lies).

You're very limited in what you can evaluate about a well system because some of the components are underground. You also don't have X-ray vision to see the adequacy of the underground water source.

You're very limited in what you can evaluate about a well system because some of the components are underground. You also don't have X-ray vision to see the adequacy of the underground water source. Some items that aren't visible are submersible well pumps, water lines and sometimes even the water storage tank. On old houses you may find the water storage tank located in a pit in the ground. To make matters worse, you have no idea of what the past maintenance history has been. These are the same limitations with evaluating septic systems, oil tanks and any underground or nonvisible item on the property. Tell the client to get documentation of the past history from the well contractor maintaining this system. They should also find out the age of the well pump and other equipment.

Most wells are over 25 feet deep, so be careful about telling your client that the system is fine. The repair costs and costs to drill deep wells are much higher than shallow wells. The reason for this is that the repair bills are usually based on the number of feet of water pipe used and the drilling depth.

Tell the client the limits of testing the system and the evaluations that you can make during a limited time, visual inspection. You're limited because the well is an underground system. Let them know that there aren't any other inspectors that will do a more thorough job. More importantly, most inspectors tend to be much less thorough than an "A to Z Home Inspector."

Before beginning your testing of the well system, turn off all of the house faucets and take a look at the well components that are above ground. You can usually find the visible well components in the lower level of the house. Look at the well system pressure gauge and record what the reading is. This is called the static pressure, since no water is being used and the system is idle. See if the pressure gauge has rust on it or if it's operating properly.

Look at the well water lines to determine their condition. I'll give you some background on different types of well pipe materials. You won't need to know this for most inspections, but it may come in handy. Most of the time you'll find black polypropylene pipe, which looks like plastic, used for well water lines. This type of pipe is good for wells up to 300 feet deep. It has a 200 psi maximum pressure rating and is installed in one, long section with no joints. Schedule 80 PVC pipe should be used for wells over 300 feet deep. This pipe have very thick walls to help prevent long term repair problems. Unlike the polypropylene pipe, schedule 80 PVC pipe comes in 20 foot sections. At the end of each section there are threaded grooves to attach the next pipe length. Schedule 40 PVC pipe is not as strong as schedule 80 pipe. The 20 foot sections of schedule 40 pipe are glued together, as opposed to having threaded ends. Schedule 40 pipe has a 400 psi maximum pressure rating. However, this pipe gets brittle after being in a well for many years. Also, the glue used to hold the sections together becomes weak over time.

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