If you live in Baton Rouge, you’re no stranger to hot, humid afternoons that end in sudden downpours. From May through September, our subtropical climate creates the perfect conditions for frequent summer storms that can wreak havoc on your backyard pool. From unbalanced water chemistry to increased debris and algae growth, rainy weather introduces unique challenges for pool owners. The good news? With the right maintenance routine, you can keep your pool swim-ready all season long. Here’s how to care for your pool during Baton Rouge’s rainy summer months.

How Rain Affects Your Baton Rouge Pool’s Chemistry

Rainwater in Baton Rouge is typically more acidic than the national average, posing unique challenges for pool owners—especially those with gunite pools. When this acidic rain enters your pool, it dilutes key sanitizers like chlorine and disrupts the water’s delicate chemical balance. Specifically, it lowers both pH and total alkalinity, creating a more corrosive environment.

Left unchecked, this imbalance can lead to long-term damage:

• Erosion of plaster surfaces
• Corrosion of metal fixtures and equipment
• Accelerated wear on pumps and filters

In addition to rain, runoff from nearby landscaping or pool decks can introduce organic matter, soil particles, and other debris—further increasing the risk of algae blooms and cloudy water.

To complicate matters, the tap water commonly used to top off pools in Baton Rouge is moderately hard. This means it contains elevated levels of calcium and other minerals. The interaction between acidic rainwater and hard fill water creates a chemical tug-of-war, requiring regular testing and balancing to keep your pool water safe, clear, and equipment-friendly.

How to Prepare Your Pool Before a Rainstorm Hits

Baton Rouge’s summer thunderstorms can come on quickly and with intensity, so taking the following steps before the rain starts can protect your pool, minimizing damage and costly repairs.

1. Lower your water level by about two inches

Before heavy rainfall, slightly reduce your pool’s water level. Drain about 1–2 inches, just enough to leave room for incoming rainwater without exposing skimmers. This helps prevent overflow and keeps your chemical levels from getting too diluted when rain arrives.

2. Keep your pump and filter running

Run the pump before and during light to moderate rain. Continuous circulation helps disperse rainwater evenly and prevents dead zones where algae can form.

3. Cover the pool if possible

Using a high-quality pool cover reduces the amount of debris and acidic rainwater that gets into the pool during a storm.

Maintaining Your Pool After Summer Storms

Immediately following any summer rain showers, restore your pool’s chemical balance to ensure it is safe for swimming.

1. Test your water immediately

• pH - ideal range: 7.2 to 7.6
• Total alkalinity - ideal range: 80 to 120 ppm
• Calcium hardness - ideal range for gunite pools: 200 to 400 ppm

2. Adjust your chemicals in the correct order

Chemical adjustments must follow a logical sequence for effectiveness:

• First, correct total alkalinity using sodium bicarbonate (baking soda).
• Next, adjust pH using soda ash to raise it or muriatic acid to lower it.
• Then, if needed, adjust calcium hardness to protect your gunite surface.

3. Shock the pool

Rainstorms often bring organic debris into your pool that promotes algae growth.

• Use a chlorine-based pool shock to sanitize and oxidize contaminants.
• Follow label instructions carefully, and allow for proper circulation before retesting.

• Skim the pool’s surface
• Vacuum the pool bottom to remove sediment
• Empty your skimmer and pump baskets to maintain proper water circulation

5. Keep your filter running continuously

Run your filtration system until the water is clear and all chemical levels have stabilized.

• This may take 24 to 48 hours or more, depending on how much rain entered the pool.
• Backwash or clean your pool filter as needed to maintain efficiency.

6. Retest your water after 24 hours

Once your pool has circulated and settled:

• Retest all chemical levels to ensure they are within the recommended ranges
• Only resume regular swimming once the water is both clear and chemically balanced

By taking a few smart, proactive steps before and after each rain event, you can protect your pool from damage, maintain water clarity, and ensure your swimming environment stays safe and enjoyable. Consistent maintenance not only extends the life of your pool but also saves you time, money, and stress throughout Baton Rouge’s stormy summer season. If you need expert help maintaining your pool, contact Lucas Firmin Pools today for reliable local service and customized pool care solutions.