Rain Harvesting First Flush Diverter | Wall/Post Mount | 3"-4" Filter

📏 Key Features

• Model: WDPW110

• Application: Suits 3" (90mm) and 4" (100mm) round downpipes

• Mounting Style: Wall or post-mounted

• Material: UV-stabilized PVC construction

• Capacity: Adjustable via diverter pipe length

• Included Components:

  • Diverter T-junction

  • Ball and seat mechanism

  • Mounting brackets

  • End cap and slow-release drain valve

✅ Benefits

• Space-Saving Design – Mounts cleanly to walls or posts when vertical downpipe space is limited

• Improves Water Quality – Removes the most polluted water from each rain event before it enters your tank

• Adjustable Volume – Customize the diverter pipe length to suit your roof size and local rainfall

• Durable Build – UV-resistant materials ensure reliable performance in outdoor conditions

• Easy Maintenance – Accessible components allow for quick inspection and cleaning

🔧 Installation Overview

1. Choose a wall or post location near your downpipe

2. Connect the diverter kit inline with a 3" or 4" downpipe

3. Adjust the diverter pipe length to match the desired first flush volume

4. Secure with included brackets and test slow-release valve functionality

📦 Shipping & Handling

• Package Dimensions: 24" L × 10" W × 8" H

• Shipping Weight: Approximately 5 lbs

• Packaging: Individually boxed with mounting hardware and instructions

• Delivery Method: Ships via standard ground service
  
  

The benefit of one larger unit is that it can be easier to maintain than a series of smaller diverters installed at each downpipe.

The first flush of water from the roof can contain amounts of bacteria from decomposed insects, bird and animal droppings and concentrated tannic acid. It may also contain pollen, water borne heavy metals and chemical residues, all of which are undesirable elements to have in a water storage system. Rain Harvesting's range of First Flush Water Diverters (or Roof Washers) capture the first most contaminated rainwater from the roof and gutters, automatically diverting the subsequent cleaner rainwater to the storage tank.

Diverter end caps contain 6.52 gallons.

Requires six sections of 4" PVC pipe which can be purchased online or at a local plumbing supply.

Product Improvements from Previous Design:

 

• No More Bulky 12" Pipe

Easily divert large volumes of first flush with the Delta High Volume Chamber. Utilizing six four inch pipes to create the diversion chamber, the Delta’s revolutionary design makes installation a breeze.

 

• Integrated Ball and Seat

The new unique design ensures that the first flush ball remains close to the seat, even in high flow events, making certain that the diverter seals as soon as the chamber is full. This means no more lost balls, when cleaning your outlet!

 

 

• Divert Larger Volumes

By allowing you to determine the frequency of first flush, the Advanced Release Valve ensures that the Delta’s first flush diversion is optimized. The transparent, rapid release exit funnel reduces build up and blockages while allowing for easy visual inspection.

Diversion Recommendations for the Roof

Minimal Pollution: divert 0.0125 gallons per square foot of roof area Open field, no trees, no bird droppings, clean environment Substantial Pollution: divert 0.05 gallons per square foot of roof area Leaves and debris, bird droppings, various animal matter, e.g. dead insects, lizards, etc. Example for a minimal polluted roof of 1,000 square feet: 1000 square feet X 0.0125 = 12.5 gallons to be diverted Example for a heavily polluted roof of 1000 square feet: 1000 square feet X 0.05 = 50 gallons to be diverted

PVC Pipe Specifications

3" Downspout diverters: Use 3" Schedule 40 PVC (not sewer and drain pipe) Storage capacity: Each 3 foot section of 3" PVC holds approximately 1.1 gallons of water (0.3840341 gal/ft) 4" Downspout diverters: Use 4" Schedule 40 PVC (not sewer and drain pipe) Storage capacity: Each 3 foot length of 4" PVC holds approximately 2 gallons of water. (0.661312 gal/ft) Post/Wall and In-ground First flush diverters: Use 4" Schedule 40 PVC Storage capacity: See chart below, for exact calculations