The document discusses various components of sewerage systems and methods of sewage collection and treatment. It describes the key parts of sewerage systems including pipes, pumps, manholes, as well as different systems for collecting domestic and industrial wastewater. It also summarizes common methods for primary and secondary sewage treatment such as screening, sedimentation, and biological processes like trickling filters and activated sludge. Stormwater management techniques are also outlined including ways to store, convey, and infiltrate or detain runoff.

2. Sewerage system, network of pipes, pumps,
and force mains for the collection of wastewater,
or sewage, from a community. domestic and
industrial sewers and storm sewers.
Separate System
Combined System

3. Methods of Collection
• Conservancy System this system is also called dry-System
The night soil is taken outside the town in closed animal
drawn carts, trucks or tanks mounted on the trailers. The
night soil is buried in trenches.
• In conservancy system the Sullage and Storm waters are
also carried out separately in closed or open drains, upto
the point of disposal, where they are allowed to mix with
stream, rivers or sea without any treatment.
• Water-Carriage System With the development
and advantages of the cities, urgent need was
felt to replace conservancy system with some
more improved types of system in which human
agencies should not be used for the collection
and conveyance of the sewage. After a large
number of trials it was found that the water is
the only cheapest substance, which can be easily
used for collection and conveyance of sewage.

4. SEWAGE SYSTEM
Open Channels and Drains

5. DRAINAGE PLANS OF BUILDINGS
Ventilating pipes: The drain pipes carrying waste water and
sewage should be provided with at least one ventilating
pipe.
Anti-siphonage pipes:
Manhole and inspection chamber: At every change of
alignment, gradient, or diameter of a drain, there should
be a manhole or inspection chamber. .
Rain water pipes: A rain water pipe conveying rain water
should discharge directly or by means of a channel into
or over an inlet to a surface drain or shall discharge
freely in a compound drained to a surface drain.
Roof gutters:

6. • SYSTEMS OF PLUMBING
• There are four systems adopted in
plumbing of drainage work in a
building
• Single stack system
• One pipe system
• One pipe system partially
ventilated
• Two pipe system
• 1.Single stack system-This is a
simplified one-pipe system
without ventilation pipe work.
The trap of water closet, sinks,
basins, is directly connected to
single stack. The pipe, in addition,
also acts as a vent pipe. The single
stack system is economical.
• 4. Two pipe system
In this system two pipes are
provided. One pipe collects all
soil wastes from urinals and
lavortary wastes. The other
pipe collects the unfoul water
from kitchen, bathroom,
house washings, rain water,
etc. The soil pipes are directly
connected to the drain.
2. One pipe system-a single soil waste
pipe conveys both soil and waste
directly to the building drain. A
separate vent pipe is provided.
Hence, it is more effective than the
single stack system. The vent pip
provides ventilation to water seal of
all the traps.
3. One pipe system partially ventilated
This system combines the one pipe and
single stack system. In this system,
only one soil waste pipe conveys
both soil and waste. The separate
vent pipe provides ventilation only
to the traps of water closets.

7. TRAPS ACCORDING TO SHAPE
‘P’ TRAP
‘S’ TRAP

8. • TRAPS
A trap is a fitting provided in a drainage system to
prevent entry of foul air or gases from the sewer or
drain into the building. The barrier to the passage of
foul air is provided by the water seal in the trap.
(i) Floor trap (Nahani trap)
(ii) Gulley trap
(iii) Intercepting trap
(iv) Grease and oil traps
• Floor Trap (Nahani Trap)
• Floor traps are provided in floors to
collect waste water from kitchen
sinks, bathroom floors, washing
floors, etc. A floor trap forms the
starting point of waste flow.
provided with a removable grating at
top so as to prevent the entry of
solid matter.
• gulley trap is usually situated near the
external face of the wall. It disconnects
the waste water flowing from kitchen,
bathroom, wash-basin and floors from
the main drainage system This is a deep
seal trap forming a barrier for preventing
the foul gases from house drain to the
inside of the building.
Multi-floor Trap

9. INTERCEPTING TRAP
• This trap is provided at the junction
of house drain (inspection chamber)
so as to prevent the entry of foul air
from public sewers to the house
drain. Provided with an inspection
arm for the purpose of cleaning or
inspection The inspection arm is kept
closed by a lid or plug.
GREASE AND OIL TRAPS
These are chambers
provided on the sewer
line to exclude grease and
oil from sewage before it
enters the sewer line
These traps work on the
principle that grease or oil
being light in weight float
on the surface of sewage.

10. A sludge soak pit is the one in which
the sewage effluent from the house
drain is directly discharged. The water in
the accumulated sewage is soaked by
adjoining pervious soil while the sludge
is digested in the pit.
Manholes or inspection chamber
• These are masonry or RCC structures, constructed at
suitable intervals along the sewer lines, for the purpose
of cleaning the sewer lines. They also help in joining the
sewer lines and in changing the direction or alignment
as well as gradients of sewer lines. Manholes are
directly constructed over the center line of sewer. Their
shape in plain is circular, rectangular or square.

11. SEPTIC TANK
(sometimes called a backflow or sewer backup valve)
is a valve you can install on your sewer line and is
designed to allow water or sewage to flow only one
way, that is, out of your house.
Anytime there is a sudden heavy rainfall, the city
sewer lines can become overwhelmed, causing water
or sewage to flow back towards your home.
If there is a sewer system backup, and you have a
backwater valve in place, sewage will not be able to
flow back into your house.
Backwater valve

12.  Soil pipe: A soil pipe is a pipe Through which human excreta flows.
 Water Pipe: it is a pipe which carries only the liquid waste. It does not carry human
excreta.
 Vent pipe; it is a pipe which is provided for the purpose of the ventilation of the system. A
vent is open at top and bottom, to facilitate exit of foul gases. It is carried at least one
meter higher than the roof level.
 Rain water pipe: it is a pipe which carries only the rain water.
 Anti-siphonage pipe: it is pipe which is installed in the house drainage to preserve the
water seal of traps.

13. Brick Sewers
Vitrified Clay
Cement Concrete Sewer Pipes
Steel Pipe Sewers

14. SEWAGE TREATMENT

15. PRIMARY TREATMENT
SCREENING - Sewage arriving at a disposal work is first
passed through a metal screen which intercepts large
floating objects such as pieces of wood, rags, masses of
garbage and dead animals. Their removal is necessary to
prevent clogging of the treatment plant.
GRIT CHAMBER - Sewage is then passed through a long
narrow chamber called the grit chamber or detritus
chamber. This chamber is approximately 10 to 20 metres
in length. The function of the grit chamber is to allow the
settlement of heavier solids such as sand and gravel, while
permitting the organic matter to pass through.
PRIMARY SEDIMENTATION - Sewage is now admitted into
a huge tank called the primary sedimentation tank. The
sewage spends about 6-8 hours in the tank. Nearly 50-70
per cent of the solids settle down under the influence of
gravity. The organic matter which settles down is called
sludge and is removed by mechanically operated devices,
without disturbing the operation in the tank.

16. SECONDARY TREATMENT
The effluent from the primary sedimentation tank still
contains a proportion of organic matter in solution or
colloidal state, and numerous living organisms.
TRICKLING FILTER: The trickling filter or percolating filter
is a bed of crushed stones or cinker, 1 to 2 m deep and 2
to 30 m in diameter, depending upon the size of the
population. The effluent from the primary sedimentation
tank is sprinkled uniformly on the surface of the bed by a
revolving device. Over the surface and down through the
filter, a very complex biological growth consisting of
algae, fungi, protozoa and bacteria of many kinds occurs.
This is known as the "zoogleal layer". As the effluent
percolates through the filter bed, it gets oxidized by the
bacterial flora in the zoogleal layer.
ACTIVATED SLUDGE PROCESS
The effluent from the primary sedimentation tank is mixed with
sludge drawn from the final settling tank.
The proportion of activated sludge to the incoming effluent is of
the order of 20 to 30 per cent. The mixture is subjected to
aeration in the aeration chamber for about 6 to 8 hours.
During the process of aeration, the organic matter of the sewage
gets oxidized into carbon dioxide, nitrates and water with the
help of the aerobic bacteria in the activated sludge. The typhoid
and cholera organisms are definitely destroyed, and the
coliforms greatly reduced.aeration tank

17. STORM WATER MANAGEMENT

18. 1. Collection Area – roof surfaces provide an opportunity for
rainwater capture.
2. Conveyance System – used to transfer water and is comprised of
gutters or flat roof drainage holes, and downspouts and piping.
3. Water Storage – may be above or below ground and can be
comprised of a single container or multiple containers.
4. Filtration – to keep debris out of the system.

19. Stormwater management is the effort to reduce runoff of
rainwater or melted snow into streets, lawns and other sites
and the improvement of water quality.
When storm water is absorbed into the soil, it is filtered and
ultimately replenishes aquifers or flows into streams and rivers.
water creates excess moisture that runs across the surface and
into storm sewers and road ditches. This water often carries
debris, chemicals, bacteria, eroded soil, and other pollutants,
and carries them into streams, rivers, lakes, or wetlands.
Construction of roads or
buildings significantly
changes the hydraulic
properties of an area.
 Storage Type Devices
 Infiltration Type Devices

20. SURFACE RUNOFF
Infiltration excess occurs when the rate of
rainfall or snowmelt is greater than the
infiltration capacity. The water that
cannot infiltrate becomes surface runoff.
As the rain continues, water reaching
the ground surface infiltrates into the
soil until it reaches a stage where the
rate of rainfall (intensity) exceeds the
infiltration capacity of the soil.
INFILTRATION TRENCHES

21. Detention Ponds
Detention ponds are excavated reservoirs or
constructed in natural depressions, which
are dry during low flow periods. They
provide temporary storage of storm water
runoff attention for both storm water
quality and quantity management.
hold water for a short period of time
Retention Ponds
Only the excess runoff is discharged
through the barrel to an external water
body. This means that there is always
water in the pond, unless it dries up

22. RAIN WATER HARVESTING
•Roof top rain water harvesting system
•Surface runoff rain water harvesting system
Rain water harvesting is a
technique of collection and
storage of rainwater into natural
reservoirs or tanks, or the
infiltration of surface water into
subsurface aquifers (before it is
lost as surface runoff). One
method of rainwater harvesting is
rooftop harvesting
RWH- process of collecting,
conveying & storing water
from rainfall in an area – for
beneficial use.

23. Percolation Pit

24. The surface water is recharged into the aquifer
through trenches, wells, or other facilities
Recharge Well
A recharge well pushes back surface water into
the groundwater system.

25. Green Roofs
consist of a thin layer of vegetation
and growing medium installed on top
of a conventional flat or sloped roof.
which reduces stormwater run-off
reduce urban heat island effects, and
create green space for passive
recreation or aesthetic enjoyment.

26. Roof catchment systems