Methods of Rainwater Harvesting, Types of Rural Sanitation and Types of Plumbing Fixtures
• What is it?
Rainwater harvesting is the accumulation and deposition of rainwater for
reuse on-site, rather than allowing it to runoff.
• What are its uses?
Uses include water for garden, water for livestock, water for irrigation, water
for domestic use with proper treatment, and indoor heating for houses etc.
Rainwater Harvesting Systems
A rainwater harvesting system has six main functions:
• To collect rainwater from the roof and gutters
• Transport the water through the downspouts and piping
• Remove debris and pre-clean the water
• Store the water
• Pressurize the water to the intended use
• Disinfect the water if the water is being used for potable (drinking)
Various Traps Used
Rooftop rainwater harvesting
In rural areas, this is most often done at small-scale. It is a simple, low-cost technique
that requires minimum specific expertise or knowledge and offers many benefits.
Rainwater is collected on the roof and transported with gutters to a storage reservoir,
where it provides water at the point of consumption or can be used for recharging a
well or the aquifer.
• A catchment area or roof surface.
• Delivery systems (gutters)
• Storage reservoirs or tanks
• An extraction device (depending on the location of the tank - may be a tap, rope
and bucket, or a pump)
• Catchment Area:
To be ‘suitable’, the roof should be made of some hard material that does not
absorb the rain or pollute the run-off.
Tiles, metal sheets and most plastics are suitable, while grass and palm-leaf roofs
are generally not suitable.
If a roof does not provide enough catchment area, plastic sheets can be used to
enlarge the catchment surface.
Select materials that are non toxic and inert.
• Delivery System: The delivery system from rural rooftop catchment usually
consists of gutters hanging from the sides of the roof sloping towards a down pipe
Gutters should be made of inert materials. The
most common gutters are continuous, baked
aluminum gutters made and installed on site.
Half-round vinyl is also excellent.
When installing gutters make sure that there is a continuous slope towards the
downspouts, and that there is no impediment to slow the flow of debris into the
These are areas where the water can pool or collect insects, organic materials and
bacteria. Think of a gutter as a river - not a wetlands or swamp.
• Gutter Guard: It keeps some debris out, but
it also protects the debris that collects in
the gutter, from the sanitizing and self
cleaning of sun and wind.
• Downspout: Anything from chains to
traditional aluminum downspouts can be
used to get the water down from the
• Debris Traps: Debris traps and filters are
necessary to clean the water as much as
possible before it enters storage.
• Final Sediment Filtration: For potable water systems
the water is usually passed through some form of fine
mesh screen filter as a final cleaning before entering
the storage tank or cistern.
• First Flush Diverter: Routes the first flow of water
from the catchment surface away from the storage
tank. Designed to fill with contaminated water from a
rain event and empty itself over a 24 hour period so
that it is ready for the next time it rains.
• Surge/Pump Tanks: It is used where it is not possible
for roof water to run by gravity to the cistern. The
tank sizing depends on the roof size, the pump size
and the desired storage capacity.
• Harvested rainwater is stored in storage tanks or cisterns.
• The most common storage tanks are the above ground molded polyethylene tanks
ranging in size from 300 to 3,000 gallons.
cisterns 4,000-30,000 gallons
that are made of culvert
engineered, and easily
transportable to most sites.
Groundwater storage system
• It involves using a piece of surface of ground for harvesting rainwater for small
• Catchment area is made smooth and impervious using clay tiles, tiles, plastic or
• Land has to be altered for contouring, clearance of rocks and vegetation etc. to
• Sanitary Rope and Bucket System
• Bucket Pumps
• Chain Pumps
• Hand pumps
• Micro basins: Small pools are surrounded by
stone walls and/or soil ridges on all sides to
collect the rainwater and surface run off .
• Bunds: They are built along contour lines to
collect surface run-off. Thus, enhancing
infiltration and moisture content of soil.
• Retention Basins: They are used to
collect surface runoff and to improve the
quality of water by natural processes such
as sedimentation, decomposition
solar disinfection and soil filtration.
Methods of Rural Sanitation
"Sanitation generally refers to the provision of facilities and services for
the safe disposal of human urine and feces”.
The word 'sanitation' also refers to the maintenance of hygienic conditions,
through services such as garbage collection and wastewater disposal.
The Joint Monitoring Programme for Water Supply and
Sanitation of WHO and UNICEF has defined improved sanitation as follows:
• Flush toilet
• Connection to a piped sewer system
• Connection to a septic system
• Flush / pour-flush to a pit latrine
• Ventilated improved pit (VIP) latrine
• Pit latrine with slab
• Composting toilet
• Elbows: Used to change the angle or direction of the pipe run.
• Street Elbows: One end of the fitting has male threads and the other end has
• T-fittings: Allow branching of lines and are shaped like the letter T.
• Couplings: Used to join two straight pieces of
pipe of the same diameter.
• Reducers: Reducers join pipes of different
• Bushings: Used to make the diameter of a pipe
• Unions: Used to join pieces of pipe where pipes
cannot be turned or when a piece of equipment
may have to be removed for maintenance or
• Adaptor fittings: These used to change the end of a non-
threaded pipe to male or female threads as needed.
• Caps: Used to close the end of a dead end pipe.
• Plugs: Close an opening on a pipe fitting normally used
for inspection and cleanout.
• Wyes: Used primarily to gain inside access to DWV
Testing of pipes
• Before pipe connections are made, pressure tests and bacteriological tests