About 12% of New Jersey homes are served by private water wells. Although the majority of the components of a private well are not visible it is important for the NJ home inspector to understand how private water wells supply water and the issues sometimes seen with these systems.
The most common type of residential well is a drilled well. A drilled well is typically drilled over 100 feet deep. They are deep and enter past the bedrock which supplies a more reliable well. Drilled wells are less prone to contamination because of their advanced depth.
Well water comes from aquifers which are pockets of water deep in the earth. An aquifer is somewhat analogues to an underground small reservoir. Rainwater saturates the soil and most of it ends up as surface water an example would be water then ends up in a river or stream. Some of this water makes its way deep into the earth and becomes what is known as ground water. Water makes its way deep into the soil until it reaches the saturation zone. The saturation zone is also called the water table. This is where well water comes from. If all goes well the water table will be able to replenish itself over time.
Parts of a residential well system.
Well head: The very top of the well is called the well head this is typically the blue cover that we are used to seeing in the field. The purpose of the cover is to keep material out of the well. Electrical wires also enter here and are also protected from the elements and protected from people coming into contact with them.
Well casing: The well casing is the outer wall of the well. The casing provides support, so dirt, gravel, rock, and sand do not obstruct the well. The casing also acts as protection to the electrical wires, the piping, and the safety rope. (The safety rope attaches the pump to the well head and prevents the pump from being lost inside the well if there were to be a pipe separation in the well). Well casings are typically made of steel but newer well casings are now made of PVC. PVC does not corrode and has significant durability.
Well pump: The pump is the heart of the well that takes water from the well to the home. Electric well pumps draw water from the inside of the well casing and deliver the water through a black plastic water pipe to the home.
The most common type of well pump is the submersible: A submersible pump sits deep inside the well sitting in the water and is powered by electricity. These submersible pumps can last 15-20 years but statically the life expectancy is about 10 years.
Well screens: Well screens provide sediment entry protection at the well bottom. The well screens act as the filter for the well. Sand and dirt particles can create early failure of the well pump or cause problems to the water systems and fixtures in the home.
Pressure tank: The component that creates the water pressure in the home is the well pressure tank. The pressure tank has two things water and air. Water is located at the bottom of the tank and air at the top of the tank. The pressure tank has compressed air and is typically set at 40 to 60 PSI. The compressed air pushes the water from the tank when water is called for in the home at a fixture. Water from the well enters the bottom of the well tank. As water in the tank rises air is compressed at the top of the tank. Once pressure is achieved the well pump tuns off. When water is called for the air forces the water out of the tank and creates domestic water pressure in the home. Once the water level drops a switch activates the well pump again and the cycle continues. A well pump is typically engaged when pressures are reduced to avoid 30-40 PSI in the well tank. This cycling helps extend the life of the well pump because it does not have to turn on each time someone in the home calls for water.
Although inspecting a well is beyond the standards of a New Jersey home inspection there are some things that home inspectors can check. A New Jersey home inspector can check the well head and cap to make sure it is in good condition and tight to the top of the well casing. The home inspector can check to see if there are any unprotected wires at the top of the well head. Inside the home an inspector can inspect the well pressure tank to make sure that there is no rusting or leakage. I would also recommend the inspector look at the main water valve. These valves are almost always rusted and in poor condition due to the sweating of the exterior of the pressure tank. The well tank sweats and can create mold to form on the exterior of the cold metal tank. A home inspector should also check the pressure tank for surface mold. The inspector should also check the pressure gauge and make sure that it is not waterlogged. Often the gauge will be fouled because water has entered it. The NJ home inspector should also operate water in the home using a multiple fixture test. This is done by simply operating water simultaneously at two bathrooms to determine if there is a significant pressure drop.
NJ home inspectors should explain that the client may want to have a separate well inspection by a professional well company. This inspection will go way beyond what a home inspector can look for during a visual home inspection.
One test that I would recommend home buyers have performed from a well company is a well flow rate test. Flow rate is vital for the operation of a household. The average person typically uses about 80 gallons of water per day. A well inspector will be able to calculate the flow rate need for the number of people in the household and make sure that there will be adequate water flow.
Home inspectors in NJ should be familiar with the operation of a private well and should be able to educate their clients on how a water well works. Home inspectors should be able to inspect the visual components of a well including the well head, pressure tank and gauge as well as provide a simple water pressure test.