Swimming pools routinely need to have water added, either when they are opened up again after they've been winterized for part of the year in cold climates, or because simple evaporation and heavy use have caused some of the water to vanish.
How you go about this depends on how much water you have to add. Smaller amounts can be added from your garden hose, but for a larger filling, you may want to contact your utility company to ask for an adjusted rate. Because this is water that will be in the pool permanently rather than flushing into the sewer system, some local utility companies will give you a discount on the water needed to fill a swimming pool. In rural areas or in areas where the community water supply is very expensive, you can contact a company specializing in truck delivery of water. In a rural area where the ground water contains a lot of minerals, you may prefer to buy delivered water rather than put hard mineral water from a well into your pool.
For smaller fill-ups, though, it's just fine to run a garden hose into the pool and turn it on until the level is where it needs to be — generally about halfway up the skimmer hatch.
While filling the pool is as easy as it sounds, there are other steps you should follow during this process.
Step 1 Clean the Pool
Clean your pool by skimming the surface for debris, leaves, twigs and bugs. A manual skimmer on a pole can be used for anything the pool filter pump doesn't remove.
Step 2 Evaluate the pH
Check the pH of your pool before adding more water. If your pH is a little too acidic, adding water should help even it out. If it's not acidic enough, it's a signal that you'll have to adjust the pH after adding water.
Step 3 Add Water
Use your hose to add water to your swimming pool. Watch carefully to stop the water flow once the pool level reaches to about the halfway point on the skimmer. Most pools lose about 1 inch of water each week, but a pool might lose more in very hot or dry climates.
Step 4 Test for pH
Check your pool's pH with test strips, and adjust the chemical composition accordingly.
Step 5 Adjust the Chlorine
Because of added water, the existing chemistry of the pool may have been diluted by adding water. After every water addition, check the pool's chlorine levels and add chlorine if necessary. This is especially important if you've added a large quantity of water.