If you are looking for “how to lower pool water level” of your in-ground swimming pool, this guide should help!
You may find that heavy rain has raised the water level of your in-ground pool and needs some removed to avoid subsequent damage and overflow to surrounding foliage, or even the deck. Another reason for removing water is accidentally leaving the hose running and overfilling, or preparing your pool for the winter season. The water level may be lowered by the filter’s multi-port or a drainage spigot on the pump, if the pool is equipped with either. However, if these are not available a submersible pump can be used, or a garden hose can be used for siphoning the water.
Heavy rain is able to dangerously increase pool water levels.
How to Use Backwashing to Lower Pool Water Level (Most Popular Approach)
If you use a DE or sand filter in the pool, it will be equipped with a multiport valve. This can be used for backwashing the filter when it becomes dirty. There are two settings that can be used on the valve, Backwash or Waste, for draining pool water. Both of these settings will allow water out through the drain port. The difference is that ‘Waste’ allows water to bypass the filter, and ‘Backwash’ sends water to the filter going backwards (helping to clean it at the same time). If your filter needs cleaning, using the Backwash setting to drain the pool is best.
The first step is to turn off your pool pump prior to changing the valve handle, this will avoid any potential damages to plumbing or valves. To ensure full safety, the pump should be unplugged or disconnected power from the circuit breaker.
During normal operations, the filter is likely in the FILTER setting. Move the multiport valve handle to the BACKWASH setting by depressing it first. Ensure the handle is fully depressed prior to moving to avoid potential damage to the multiport valve seal.
Ensure the WASTE hose has been placed where you want water drained too.
Return power to the pool pump, running it for at least 2 minutes. You will notice the water changes from cloudy to clear within the sight glass located on the valve’s side.
Turn power to the pool pump OFF.
Ensure the multiport valve handle is fully depressed and change it to the RINSE setting. Once the backwashing has been completed, sand will be loose within the filter and needs resetting. This step also allows any dirty water remaining from the backwash to be rinsed from the filter, avoiding it being put back into the pool.
Turn power to pool pump back ON, running the filter for 1-2 minutes on RINSE.
Turn power to pool pump back OFF, fully depressing the multiport valve handle return to FILTER setting.
Turn power to pool pump back ON. Begin operation as normal. Make sure pressure dropped between 8 to 10 psi from where it was prior to the backwashing by reviewing the pressure gauge.
How to Use Pump Drain Plug
Pools that have cartridge filters will not require a multiport valve as the cartridge is removable for cleaning. However, the pool pump may be equipped with a drainage spigot. If your pool has this setup, it should be located between the filter and pump. Simply connect a garden hose to your drainage spigot, open flow and let the water drain out.
How to Use a Submersible Pump
Submersible pumps are built to work when under the water, and there’s a chance you may already have one for keeping the cover dry during winter months. To use it, you just attach a drainage hose on the pump, place the pump in the pool, and allow it to sink to the bottom. Then, connect power to the pump and it will do the rest by pumping water though the hose. Be sure the hose is where placed where you want the water to drain. If a multiport valve or spigot is not available, use this method.
Siphoning Pool Water
If you’re in a pinch, water can be drained by using a garden hose to siphon the water out. All you have to do is place the other end under pool water, ensuring it remains submerged. The other end should be at lower elevation.
To begin the siphon process, you have to build negative pressure within the hose to begin the flow. Sometimes, this can be done by quickly dropping the lower end of the hose. However, a common method is sucking the end to build negative pressure.
Not big on the idea of sucking water from the garden hose? You can also fill the garden hose with water, then attach a nozzle on the end. Place the open end into the pool water, then take the nozzle end to the drain location, and unscrew the nozzle. Because the water filling the hose creates a flow, it will make the negative pressure needed for starting the drainage process.
Responsibly Drain Water
When lowering pool water levels, it can be a bunch of water. For a 20ft x 20ft pool, draining only 4-inches will be nearly 1,000 gallons. If not properly drained, it can create flooding issues for both you and neighbors. To avoid these type of issues, ensure water is draining into a sewer or the street. If you’re located in the country, simply look for a natural drainage path to safely carry water off.
Tips to Winterize The Pool
If the reason you are draining the pool is to prepare for winter, below are some things to keep in mind:
- Let chlorine levels fall under 1ppm prior to draining the pool. This helps prevent chlorine being introduced to the environment. Once draining is finished, the pH level should be balanced, while more chlorine is added to return the level back between 1-3ppm.
- If the pool liner is vinyl, avoid draining it completely. You can loosen the liner this way, with potential of cracking during cold weather. If the pool has a tile or gunite liner, and the pool will be covered with a solid cover or tarp, the water only needs drained just under the skimmer level. Ensure to add a pump on the cover to ensure it remains drained during winter.
- After water level is lowered under the skimmer, turn on your pump for several minutes to allow the pipes to drain.
- Do not allow pool lights to be partially covered with the water, as it can result in the lights breaking when being froze during winter. Pool lights should be fully submerged or fully exposed.