Introduction
Heavy rain can quickly turn your pristine backyard pool into a murky mess. In this step-by-step guide on how to clean a pool after heavy rain, you’ll learn exactly what to do to restore clarity, balance chemicals, and protect your pool equipment. If your water looks cloudy or your pool is full of debris, don’t worry — this guide will walk you through the entire cleanup process.
Why Cleaning After Rain Matters for Your Pool
Rainwater doesn’t just top off your pool — it throws off your water chemistry. The sudden influx of water dilutes chlorine, disrupts pH balance, and introduces dirt, leaves, and contaminants. If left untreated, this can lead to algae blooms, clogged filters, and even damaged equipment.
Cleaning your pool after rain isn’t just about appearance — it’s essential for safe swimming, equipment longevity, and water clarity. Prompt action helps you avoid long-term issues and gets your pool swim-ready faster.
Step-by-Step Guide to Cleaning a Pool After Heavy Rain
Step 1: Skim the Surface and Remove Debris
Start by skimming large debris off the surface using a leaf net or pool skimmer. Heavy rain often dumps leaves, twigs, bugs, and dirt into the pool. Don’t let this sit too long — it can sink and clog your filter system.
💡 Pool Owner Tip: Use a deep leaf rake to collect debris from the pool bottom as well.
Step 2: Empty the Skimmer and Pump Baskets
Remove any debris from the skimmer basket and pump strainer basket. These fill up quickly after a storm and restrict water flow if not cleared. Blockages can damage your pump or reduce circulation.
⚠️ Caution: Always turn off your pump before removing baskets to prevent injury.
Step 3: Check and Adjust Water Level
Heavy rain can raise the water level above normal. Ideally, the water should sit at the midpoint of the skimmer opening. If it’s too high, use a submersible pump or manual backwash (if you have a sand or DE filter) to bring the water back to the correct level.
💡 Pro Tip: Keep your water level between one-third and one-half up the skimmer for optimal performance.
Step 4: Brush Pool Walls and Floor
Use a pool brush to scrub the walls, floor, and steps. This loosens up dirt, algae, and pollen introduced by the rain. Brushing also helps circulate water and prevent any buildup on surfaces.
Step 5: Run the Pool Filter System
Turn your pool pump and filter back on and run it continuously for at least 8–12 hours, or until the water looks clear. This helps filter out all fine debris and distribute the chemicals you’ll be adding next.
💡 Pool Owner Tip: If your filter pressure is high after a storm, backwash your sand or DE filter, or clean your cartridge filter.
Step 6: Test Pool Water Chemistry
Use a pool test kit or test strips to check levels for:
- Chlorine
- pH
- Alkalinity
- Cyanuric Acid
- Calcium Hardness
Rainwater often lowers pH and chlorine levels, so expect imbalances.
Step 7: Balance Chemicals Accordingly
Adjust your chemicals based on the test results. Here’s a quick guide:
- Low chlorine: Add chlorine shock or tablets
- Low pH: Add soda ash
- High pH: Add muriatic acid
- Low alkalinity: Use baking soda
- Low stabilizer: Add cyanuric acid
⚠️ Caution: Always follow label directions and never mix pool chemicals directly together.
Step 8: Shock the Pool
Rain introduces organic contaminants, which may not be fully addressed by your standard chlorine. Use a pool shock treatment to super-chlorinate the water and kill off bacteria or algae.
💡 Tip: Shock the pool in the evening and let it run overnight for best results.
Step 9: Vacuum the Pool
After letting the filter run and shocking the pool, vacuum up any remaining debris. Use a manual vacuum or automatic pool cleaner to get fine particles off the floor.
Common Mistakes to Avoid
- Skipping the Water Test
Many pool owners assume everything is fine if the water looks clear. But rain drastically affects chemical balance. Always test before swimming. - Waiting Too Long to Clean
Debris and contaminants multiply quickly. Address your pool within 24 hours of the storm. - Forgetting the Filter Check
If your filter is clogged, it can’t do its job. Always inspect and clean it after heavy rain. - Using Too Much Shock
While shocking is important, overdoing it can lead to chlorine lock or cloudy water. - Not Brushing the Pool
Skimming and vacuuming are not enough. Brushing disrupts biofilm and helps prevent algae.
Extra Tips & Pool Hacks
- Invest in a Pool Cover: Use a safety or solar cover during stormy seasons to reduce debris buildup.
- Use Enzyme-Based Clarifiers: These can help break down organic materials introduced by rainwater.
- Install a Rain Overflow Drain: Some pool owners add an overflow outlet to redirect rainwater.
If you’re also dealing with green water, check out our full guide on [how to clean a green swimming pool].
Conclusion
Cleaning your pool after heavy rain doesn’t have to be a hassle. With the right steps — from skimming and brushing to testing and shocking — you can quickly restore your pool’s clarity and chemical balance. Don’t let bad weather ruin your swim season. Act fast, follow this guide, and enjoy a clean, safe pool all summer long.
📌 Bookmark this guide for future rainy days!