Procedures for drilling a water well
Well drilling is the process of using the necessary machinery for drilling, also known as boring. Since it is a large-scale work that involves the use of specialized machinery and, in some cases, drilling (using explosives), it requires a certain amount of money. In addition, a building business license is required for contractors to perform work that costs more than 5 million yen, and violating this requirement may result in penalties of up to 300,000 yen or imprisonment. If this is violated, penalties of up to 300,000 yen or a fine of up to 300,000 yen may be imposed.
Cost of water well drilling: drilling
The cost of DIY well drilling generally ranges from 300,000 yen to 1,000,000 yen.
The cost of drilling a water well varies depending on the depth of the well.
When drilling water wells using a special machine with a drill on the tip, the cost depends on the depth of the well to be drilled. Generally, the cost is 300,000-500,000 yen for about 20m, and 50m. The standard cost is about 600,000 to 1,000,000 yen for 50 meters.
What if I want to use the water for drinking?
Here are some points to keep in mind if you want to use the well water installed by DIY as drinking water or domestic water. Even if water begins to flow after the pump is installed, you should have the water quality tested to see if it is suitable for drinking water. Please inquire about water quality testing at your local public health center. Even if there is no abnormality found in the health center's test, it is recommended to install disinfection equipment or a water purifier if you are concerned about the possibility of contamination by pathogens that could lead to food poisoning or infectious diseases due to changes in the environment.
Cost of water well drilling: maintenance
While you only need to pay the usage fee for tap water, you need to pay the maintenance cost of the equipment for well water. The general cost for a professional contractor is approximately 20,000 yen or more. The maintenance includes cleaning the inside of the water well, cleaning the filter, and replacing it. If you want to reduce running costs, it is essential to perform maintenance on a regular basis to detect and address repair points at an early stage. If you can do this yourself, you will basically only have to pay for the replacement of parts.
Methods and Types of Water Well Drilling
There are three main methods of water well drilling (percussion, rotary, and air hammer). Each method has its own merits and demerits, so consider the depth to be drilled, the subsurface geology, the work space, and the budget before making a choice.
The percussion method is the oldest method of well drilling. A heavy part called a "one-bit" is attached to the end of a wire rope, and the rope is moved up and down to break up the strata as the one-bit strikes the ground. This method is used to excavate relatively soft formations and can be set up with a small number of people in a short time. However, it is slower and generates more noise and vibration.
This method is used to dig by rotating a cutting edge called a bit attached to the tip. This method is capable of digging shallow to deep water wells and can be used for wells of various geological formations. Compared to other methods, this method is less noisy and quieter, and the construction period is shorter, making it suitable for drilling water wells in urban areas. On the other hand, the cost of treating the muddy water used during drilling and labor costs are higher than with other methods.
Air hammer method
The air hammer method uses compressed air pressure and the weight of a piston to impact the bit and drill the well. Compared to other excavation methods, the air hammer method is characterized by a faster rate of progress. It is suitable for drilling in hard rock formations as well as volumetric formations.
How long is the construction period for water well drilling?
The construction period for digging a water well varies depending on the size and depth of the well and the construction method, but generally speaking, it takes 7 to 10 days for water to come up to the surface.
Is an application needed to dig a water well if it's on your land?
In addition to the application for digging a well, each prefectural government has its own regulations regarding the application for a permit to build up water wells, to discharge water wells into the sewage system, and to quote water wells, so please check the website of the local government. Some municipalities may also offer subsidies if you apply to have your water well designated as a disaster prevention well.
What is the use of well water?
If it is a shallow well, it can be used as water for flower beds and vegetable gardens, or for washing cars. If the well is equipped to discharge water into the sewage system, it can be used for washing clothes, toilets, cooking, bathing, and other domestic purposes. Another advantage of groundwater compared to tap water is that it can be used stably throughout the year regardless of temperatures and seasons, as the water temperature remains constant throughout the year. In addition, groundwater tastes good because it does not contain chalky substances like tap water. In the worst case scenario, such as when the water supply is cut off due to a major disaster or the pump cannot be operated due to a power outage, a hand pump can be installed as a sub-pump for the main pump to secure water on its own, which can be considered a risk management advantage in terms of hygiene.
If I use well water, won't I have to pay for an electric water bill?
If you use well water instead of tap water, there is no electric water bill. The only cost is the electricity bill for the pump used to pump the water, which is very economical.
Is well water cheaper than tap electric water?
There is no cost for the water itself, so it is practically free, but there is always the cost of electricity to run the pumps used to assemble the groundwater.
What about the survey before drilling the water well?
Having explained the value of using water wells, which are practically free and useful in case of disasters, the last and most important point is the obvious question of whether there is water in the ground or not. This is especially important when digging as a DIY project. You can dig in the dark until you hit a water source, but even if you expend 5 or 10 meters of labor, if there is no water to begin with, it will be a waste of time and energy. Before you start digging, it is essential to know the location where you intend to build a water well. To get information on whether there is likely to be a water source there and whether the soil is suitable for digging, check the borehole survey data for the area published by the Ministry of Land, Infrastructure, Transport and Tourism. From this data, you can learn about the geology at each depth in the vicinity and the thickness of the layers, and you can make some inferences about the water content and thus the possibility of a water vein from the geological conditions.