If you are looking to permanently disconnect your water pipes, there are a few steps that you will want to follow to get the job done. Here is a guide to help you through the process.
Step 1 - Turn Off Water Supply
Begin by shutting off the main water supply to that source. You want to make sure that you also disconnect any power sources that are nearby as you are working so that you do not harm yourself.
Step 2 - Disconnect Pipe
Place a large bucket and towel under the area of the pipe to clean up any mess that the pipe may make if water comes pouring out. Then, use a wrench to disconnect the pipe from its spout or union. This may take a few tries and a lot of force depending on the location of the pipe as well as how long it has been there. Once you have removed the pipe though, allow for the water to rush into the bucket. Use the towel to clean up any mess nearby. Continue to let the bucket sit there as long as it needs to catch water from the open area. This could take a few seconds or minutes. Allow everything to dry out before moving to the next step.
Step 3 - Install a Valve
Installing a cap or a valve at the end allows you to disconnect and cover the end of the area. You will need to bring the pipe that you took off into the hardware store so that you can find a valve that will fit the opening and stay on. Once you have found the proper valve, attach it to the end by screwing it on. Use the wrench to tighten it completely so that you have no spills. Then, use a towel to wipe the area clean. Take a caulking gun and fill it with caulk. Use it to secure the edges of the valve. If you are disconnecting the pipes but may consider hooking them up again in the future, you will not need to caulk. The caulk or sealant is used for a more permanent situation.
The disconnection of the water pipes is permanent. While this process is not hard to do, it does take a great amount of caution. Make sure that as you go along, you are taking each step slowly. You do not want to remove the pipe too fast without having a bucket already in place. You also do not want to attach the valve or end cap and caulk without ensuring that the inside and outside of the pipe are dry. This project could take a few minutes for you to do, but it could also take a day or two depending on the circumstances. If you are having trouble with leaks, you will want to re-caulk as well as check the main water source.