How to Close Up an Inground Pool

Remove debris from the swimming pool. Use the pool vacuum brush as well as a skimmer net to remove leaves, twigs and other forms of debris from the pool floor and water.

Apply a coat of petroleum jelly to any metal ladders or handle bars on the pool to help prevent rust during the off-season.

Drain the water from the swimming pool so its water level is four-inches below the water filter jets. To do so, turn the pump to "backwash", which removes water up to the water filter jets. Use a submersible water pump, connected with a garden hose, to drain water below the jets.

Blow out the water lines by connected an air compressor to the water filter lines. This pushes water out of the plumbing lines and into the swimming pool. Cap off the water filter jets after you drain them. Also drain water from the heater, if applicable, by connecting the air compressor to the heater mechanism.

Test the water chemistry with a pool water test kit, which is available at any pool supply store. Adjust the pH, calcium hardness, total alkalinity and chlorine so they are all balanced according to the manufacturer's recommendations.

Place three floatation devices in the swimming pool, such as inner tubes, to maintain proper air circulation when the pool cover is in place. Secure the swimming pool cover over the water and flotation devices.