This is my working model on Rainwater Harvesting and Water Purification.
When it rains, water falls on the rooftop of the house. This water is collected through pipes and directed into a storage tank.
The collected rainwater may contain dirt and impurities, so it is sent through a 5-step filtration system:
- Big gravel removes large particles.
- Small gravel removes smaller stones and sand.
- Sand removes fine dust and mud.
- Cotton acts as the final filter to clean the water.
After this process, the water becomes clean and safe for basic household uses like gardening, cleaning, or even drinking after further purification.
This method is eco-friendly, saves water, and helps fight water scarcity.
Materials Needed:
- Cardboard base (for setup)
- Plastic funnel (or cut bottle top)
- Transparent plastic bottles (for filter stages)
- Cotton, sand, small gravel, big gravel (for purification)
- Pipe or straw (for water flow)
- Paper house model (for rooftop rain collection)
- Blue food color (to show dirty water)
- Glass or beaker (to collect filtered water)
- Color paper, labels, glue, scissors
Model Making Video Steps:
Part 1: Rainwater Harvesting Setup
- Make a house model on cardboard with a slanted rooftop.
- Attach a small pipe/straw to the rooftop leading to a funnel — this shows how rainwater flows from the roof.
- Place a storage tank (cut bottle) under the funnel to collect rainwater.
Part 2: Water Purification System
- Cut 4 bottles and invert them to create filter chambers.
- Fill each layer in this order:
- Top layer: Big gravel
- Second layer: Small gravel
- Third layer: Sand
- Bottom layer: Cotton
- Connect these bottles vertically using tape or glue.
- Place a collection glass under the last bottle for clean water.