1. Rainwater Harvesting
Owen Edgerton
September 25, 2006

2. History Developed independently across the continents India 1000BC
simple stone structures for harvesting rainwater
China Loess plateau ~ 0AD
Rainwater wells and Jars.

3. Types of RWH Systems
Source:

4. Rooftop Collection System
System components
Collection Surface
Thatched; Corrugated iron.
Gutters
Bamboo; Aluminum
Down pipe
Reservoir
Source:

5. Gutters
Source:

6. Reservoir Two types Materials:
Surface
Sub-Surface
Materials:
Metal, plastic, fiberglass, brick, compressed soil (rubble-stone blocks), ferro-cement and concrete
wood, bamboo and basket weaves as alternatives have had variable rates of success.
Usually the most expensive part of the system
Tank Sizing
1 – 40m3 Residential
>100m3 Commercial

7. RWH Safety Unpainted and uncoated surface areas Thatched Rooftops
Timber treated with chemicals to prevent rotting should never come into contact with drinking water.
Thatched Rooftops
Coconut and Anahaw palms with tight thatching are best
Rodent infestation
Insect-proofing
First Flush system

8. First flush and Filters Screen

9. Consumption Statistics
Per Capita (1990) gal/d

10. Benefits of RWH 3rd World Southwestern United States
20 liters
Food security
Income Generation
Southwestern United States
Sumida City, Japan
Reduces extensive runoff
Reduces energy use
Fiji
limited freshwater resource

11. Designing a RWH System Rainfall Collection surface area Storage volume
Quantity
Pattern
Collection surface area
Storage volume
Consumption
Cost
Management
Advanced System Components
Average rainfall for Biharamulo District, Tanzania

12. Additional Information

16. Mayan - 10th Century AD

17. http://www. metrocouncil

18. Complete System Collection Area Gutter Mesh Gutter Outlets Rain Heads
First Flow
Tank Screen
Water Tank
Insect Proofing
Tank Top Pump