How to Prepare Your Rainwater Harvesting System for a Storm

Why Storm Preparation Matters for Your Rainwater System

Storms bring intense rainfall, wind-driven debris, and potential flooding, which can: 

• Overload or contaminate tanks with dirty runoff, leaves, and debris. 
• Block gutters, downpipes, and first flush devices, reducing water collection efficiency.
• Damage tank components, such as pipe fittings, screens, or pumps.
• Lead to mosquito breeding if water stagnates due to blockagages 

By taking the right precautions, you can protect your system and ensure a clean, reliable water supply after the storm passes. 

Step 1: Clean and Maintain Your Gutters and Downpipes 

Before a storm, clearing your gutters and downpipes is essential for maximising water collection and preventing blockages. 

• Remove leaves, twigs, and debris to prevent clogging. 

• Ensure your rain heads and gutter mesh if you have it, are intact to keep debris out. 

• Check downpipes for obstructions that may cause overflowing or flooding. 

Pro Tip: Installing a rain head will filter out larger debris at your downpipe so the debris can’t reach your tank. 

Step 2: Inspect Your First Flush Diverter 

A First Flush Diverter plays a crucial role in preventing dirt, dust, and pollutants from contaminating your stored water. 

Before the storm: 

• Ensure the first flush chamber is empty so it can function correctly. 

• Check the filter and make sure it’s clear. 

• Clean out any blockages to allow proper diversion of dirty runoff. 

After the storm check the filter again and clean it if necessary. 

Step 3: Secure and Protect Your Rainwater Tank 

Your rainwater tank is a valuable water source, but extreme weather can cause damage or contamination. 

• Check tank lids and inlets – Ensure they are secure to prevent debris and animals from entering. 

• Inspect overflow outlets – Clear any blockages to enable proper overflow. 

• Anchor lightweight tanks – If your tank is smaller or unfilled, secure it to prevent movement in strong winds. 

• Turn off pumps if needed – Protect electrical components from flooding or damage. 

Step 4: Prevent Wind Damage to System Components

Strong winds can damage pipes, filters, and screens, leading to system failures or contamination. 

• Reinforce pipe connections – Ensure pipes and fittings are secure, especially if your tank is elevated. 

• Protect external pumps – Cover or relocate them to a sheltered area to prevent water damage. 

• Check tank stands and foundations – Ensure stability, especially for slimline or elevated tanks. 

Step 5: Ensure Water Quality After the Storm 

Once the storm has passed, it’s crucial to assess and clean your system before using the collected water. 

• Inspect water clarity and odour – If water looks dirty or smells unusual, avoid using it. 

• Flush your tank if necessary – If contamination is suspected, drain and clean the tank before refilling. 

• Replace or clean filters – Check tank screens, leaf eaters, and first flush filters for debris buildup.