ON-SITE
HUMAN WASTE MANAGEMENT
Non-Sewer Sanitation System
MSc. Sanitary Engineering
Dec 2024
INTRODUCTION
The process of managing human waste locally without
centralized systems. The basic requirements expected from a
human waste (excreta) disposal method are:
• Surface water must not be contaminated.
• There should be no contamination of groundwater that
may, in turn, contaminate springs or wells.
• Excreta should not be accessible to flies or other animals.
• There should be no handling of excreta; where this is
unavoidable, it should be kept to a minimum.
• There should be no odours or unsightly conditions.
• The method used should be simple and inexpensive in
construction and operation.
• The method should last for at least five years to be cost-
effective.
SIMPLE PIT LATRINES
Description: A basic hole dug in the ground with a cover.
Advantages:
• Low cost and easy to construct.
• Suitable for rural areas.
Disadvantages:
• Odor and vector attraction.
• Risk of groundwater contamination.
Example: Village-level installations in Nepal.
On average, solids accumulate at a rate of 40 to 60 L per
person/year and up to 90 L per person/year if dry cleansing
materials such as leaves or paper are used.
The volume of the pit should be designed to contain at least
1,000 L. Typically, the pit is at least 3 m deep and 1 m in
diameter. Depending on how deep they are dug, some pits
may last 20 or more years without emptying.
VIP LATRINES (VENTILATED IMPROVED PIT)
Description: Despite their simplicity, well-designed
VIPs can be completely smell free.
Features:
• Ventilation pipe to reduce odors.
• Fly screen for vector control.
Advantages:
• More hygienic than simple pits.
• Durable and long-lasting.
The vent pipe should have an internal diameter of at
least 110 mm and reach more than 300 mm above the
highest point of the toilet superstructure. Wind
passing over the top creates a suction pressure within
the vent pipe and induces an air circulation.
Aqua Privy
Description: Pit latrine with a water seal to minimize odor. It
operates using water to carry waste from the toilet to a
storage or treatment facility, typically in the form of a septic
tank or similar structure.
Mechanism: Waste decomposes anaerobically in a watertight
tank.
Advantages:
• Reduced odors and insects.
• Allows wastewater treatment
MODERN TOILET
A modern toilet is typically referred to as a "flush toilet" or
"water closet (WC)." These toilets are designed to
automatically flush waste away using water, typically through
a tank that holds water for flushing or a direct water
connection to a plumbing system. Modern toilets often
incorporate features for improved hygiene, water
conservation (such as low-flow or dual-flush mechanisms),
and comfort, such as heated seats, bidets, and sensor-
operated flushing systems.
FUTURE
REINVENTED TOILETS
Definition: Advanced toilets with no need for water, electricity, or
connection to sewers.
Features:
• Self-contained.
• Converts waste into ash or fertilizer.
Example: Bill Gates Foundation Reinvented Toilet Challenge.
Self-Contained System Advanced Waste Treatment
Compact and Portable Design Energy Efficiency
ECOSAN TOILETS
Ecosan (Ecological Sanitation) toilets are designed to manage
human waste sustainably by turning it into a resource, such as
fertilizer, instead of treating it as waste. These toilets separate
liquid and solid waste at the source and allow for their safe reuse
in agriculture or other applications.
Ecosan toilets follow the "closing the loop" concept, which
involves:
• Containment and separation of waste.
• Processing to make the waste safe and nutrient-rich.
• Reuse of treated waste products for agricultural purposes.
Source Separation Water Conservation
Cost-Effective Sustainability
PUBLIC TOILETS
Public toilets are essential infrastructure that ensures
sanitation and hygiene for the general public. They are
designed to accommodate a large number of people,
especially in public spaces like parks, transportation hubs,
and markets. The components of public toilets are carefully
chosen to ensure comfort, cleanliness, and efficiency.
Components
Public toilets consist of several key components: the superstructure
(walls, roof, ventilation), toilet fixtures (toilets, urinals, washbasins),
water supply and drainage systems, handwashing stations, lighting,
flooring, doors, and dividers for privacy. Waste disposal systems
(bins, sanitary napkin disposal), cleaning equipment, signage, and
safety features are also included. .
SEPTIC TANK SYSTEMS
Underground tanks that treat wastewater
from households or small communities.
Process:
• Wastewater enters the tank. Key Features
• Solids settle to form sludge, while lighter
• Inlet and Outlet Pipes: Control flow of wastewater.
waste floats as scum.
• Settling Chamber: Allows separation of solids and
• Partially treated liquid is discharged into a
liquids.
drain field or soak pit.
• Drain Field/Soak Pit: Facilitates absorption and
natural treatment of effluent.
Advantages:
• Effective for areas without sewer systems.
• Requires infrequent maintenance.
Limitations: Risk of overflow or failure if not
properly maintained.
Reinvented Toilets VIP Latrines in Schools
Disaster and Toilets Public Toilets in Pokhara
THANK YOU
FOR YOUR ATTENTION
