How to Lower the Water Level in Your Pool (The Super-Easy, Kid-Friendly Way)

How to Lower the Water Level in Your Pool (The Super-Easy, Kid-Friendly Way)

Sometimes you need to drop your pool’s water level—after big rains, before winter, or to fix chemistry. Good news: you can do it using your pool’s main drain and pump. Think of it like using a giant straw to sip water out—slow, steady, and safe!

Quick safety notes:

• Never change valve or filter settings with the pump ON.
• Don’t let the pump run dry (turn it off if the water gets too low).
• Don’t drain more than you must, and never fully drain an in-ground pool.
• Follow local rules about where discharged water is allowed to go.

What you’ll need

• • • Your pool’s pump and filter (with a multiport valve that has a WASTE/DRAIN setting)

    • Valves that control Skimmers and the Main Drain

    • A place for the water to go (waste line/approved drain, or safe yard area)

Part A: Lowering Water Using the Main Drain + “WASTE” (best method)

Step 1: “Freeze!” (Turn everything off)

1. 1. 1. Turn OFF the pump at the timer or switch.

      2. Make sure the system is totally still before you touch anything.

Step 2: “Point the straw to the bottom”

1. 1. 1. Find the suction valves (usually labeled Skimmer and Main Drain).

      2. Close the Skimmer valves (turn handles to OFF).

      3. Open the Main Drain valve (turn handle to ON).

**This tells the pump to drink from the pool floor instead of the surface**

Step 3: “Send water to waste, not back to the pool”

1. 1. 1. On the filter’s multiport valve, push the handle down and turn it to WASTE (or DRAIN).

         **Important: Only move this handle when the pump is OFF.**

Step 4: “Go!”

1. 1. 1. Turn the pump ON.

      2. Water will now leave the pool through the waste line (not back through the returns).

      3. Watch the water level drop. Stay nearby.

Step 5: “Stop at the line”

1. 1. 1. When the water is where you want it (for example, just below the skimmer mouth for winter or after heavy rain), turn the pump OFF.

Step 6: “Put everything back to normal”

1. 1. 1. Turn the multiport from WASTE back to FILTER (pump still OFF).

      2. Open Skimmer valves and set the Main Drain to your normal position (many pools run with both slightly open).

      3. Turn the pump ON and check for normal flow.

Part B: No “WASTE” setting? Try “Vacuum-to-Waste” (works great, too)

This is like using a floor vacuum as the straw.

1. 1. 1. Pump OFF. Set multiport to WASTE (if you have one). If you only have BACKWASH on a push-pull valve, use that for small drops.

      2. Attach your vacuum head to the vac hose, put the head on the pool floor, and connect the other end to the skimmer.

      3. Pump ON. Slowly move the vacuum head on the floor. Water and debris go out to waste, dropping the level.

      4. Pump OFF when you’re done. Return valves and multiport to FILTER, then Pump ON again.

No waste option at all? Use a submersible pump with a discharge hose to a safe drain area (follow local rules).

How low is “low enough”?

• • • After heavy rain: Lower to mid-skimmer (about halfway up the skimmer opening).

    • Before winter: Follow your pool type’s recommendation (often 4–6 inches below the skimmer/returns, but check your cover type and builder’s guidance).

    • Vinyl liners: Don’t drop water too far—the water holds the liner in place. Avoid going below the shallow-end floor without pro advice.

Pro tips (easy wins!)

• • • Open the main drain slowly. If you hear the pump slurp air, stop immediately.

    • Watch your pressure gauge. If pressure drops suddenly, you might be sucking air—turn off and recheck valves.

    • Mind the outflow. Let high chlorine levels dissipate a day if you’re discharging to a landscaped area (follow local discharge rules).

    • Go slow and stay close. Lowering water is not a “set and forget” task.

Quick Checklist (print me!)

• • • • Pump OFF

      • Skimmers CLOSED, Main Drain OPEN

      • Multiport set to WASTE/DRAIN

      • Pump ON, watch the level

      • Pump OFF at target level

      • Multiport back to FILTER

      • Valves back to normal

      • Pump ON and confirm normal circulation

If anything looks or sounds weird (gurgling air, sudden pressure changes, or you’re unsure which valve is which), pause and call US AT (631) 707-3070!