The document discusses various aspects of sustainable water systems and sanitation. It defines a sustainable water system as one that provides adequate water quality and quantity now and in the future without compromising capacity. It discusses different water sources like surface water, groundwater, rainwater harvesting and reclaimed water. It also discusses sustainable practices for water supply, sanitation facilities, concepts of sustainability in sanitation, and components of storm water drainage systems like inlets, piping, and outlets. Sustainable urban drainage systems are recommended to reduce stormwater flows into sewers.

2.  Sustainable water systems should provide adequate
water quantity and appropriate water quality for a
given need, without compromising the future ability to
provide this capacity and quality.
 Accessing the sustainability features in water supply,
that is to say, the three fold goals..
ECONIMIC
FEASIBILITY
SOCIAL
RESPONSIBILTY
ENVIRONMENT
AL INTEGRITY

3.  Water is used (1) for drinking as a survival necessity,
(2) in industrial operations (energy production,
manufacturing of goods, etc.), (3) domestic
applications (cooking, cleaning, bathing, sanitation),
and (4) agriculture.
 Sustainable water supply is a component of integrated
water resource management, the practice of bringing
together multiple stakeholders with various
viewpoints in order to determine how water should
best be managed.
 In order to decide if a water system is sustainable,
various economical, social and ecological
considerations must be considered.

7. Surface water
 Surface freshwater is unfortunately limited and
unequally distributed in the world.
 In addition, pollution from various activities leads to
surface water that is not drinking quality. Therefore,
treatment systems (either large scale or at the
household level) must be put in place.
 Structures such as dams may be used to impound
water for consumption.
 Dams can be used for power generation, water supply,
irrigation, flood prevention, water diversion,
navigation, etc. If properly designed and constructed,
dams can help provide a sustainable water supply.

8.  The design should consider peak flood flows
,earthquake faults, soil permeability, slope stability
and erosion, water table, human impacts, ecological
impacts (including wildlife) and other site
characteristics.
 There are various challenges that large-scale dam
projects may present to sustainability.
 A sustainability impact assessment should therefore
be performed to determine the environmental,
economic and social consequences of the
construction.

9. Ground water
 Groundwater accounts for greater than 50% of global
freshwater; thus, it is critical for potable water.
 Groundwater can be a sustainable water supply source
if the total amount of water entering, leaving, and
being stored in the system is conserved.
 There are two main factors which determine the
source and amount of water flowing through a
groundwater system:
PRECIPITATION EVAPORATION

10.  Various practices of sustainable groundwater supply
include-
 It is important to integrate groundwater supply within
adequate land planning and sustainable urban
drainage systems.
Changing the volume of
ground water in storage at
different time scales
Decreasing recharge from
the ground water system
Increasing recharge to the
ground water system
Changing rates or spatial
pattern of ground water
system

11. Rainwater Harvesting
 Collecting water from precipitation is one of the most
sustainable sources of water supply.
 Reduces over-exploitation of groundwater and surface
water sources.
 Directly provides drinking water quality.
 Rainwater harvesting systems must be properly
designed and maintained in order to collect water
efficiently.
 Must be treated to prevent contamination.

12. Reclaimed water
 Reclaimed water, or water recycled from human use,
can also be a sustainable source of water supply.
 It is an important solution to reduce stress on primary
water resources such as surface and groundwater.
 There are both centralized and decentralized systems
which include greywater recycling systems and the use
of micro porous membranes.
 Reclaimed water must be treated to provide the
appropriate quality for a given application (irrigation,
industry use, etc.)
 It is often most efficient to separate greywater from
blackwater, thereby using the two water streams for
different uses.

13.  Greywater comes from domestic activities such as
washing, whereas blackwater contains human waste.
The characteristics of the two waste streams thus
differ.

14. Desalinization
 Desalinisation has the potential to provide an
adequate water quantity to those regions that are
freshwater poor, including small island states.
 A widely used procedure is involved in REVERSE
OSMOSIS for removing salt and adaption of this
technology is a challenge.
 If desalination can be provided with renewable
energies and efficient technologies, the sustainable
features of this supply source would increase.

17.  The urgency for action in the sanitation sector is
obvious, considering the 2.6 billion people world-wide
who remain without access to any kind of improved
sanitation, and the 2.2 million annual deaths (mostly
children under the age of 5) caused mainly by
sanitation-related diseases and poor hygienic
conditions.

18. Improved sanitation
facilities
 These are facilities which
are not shared or public:
 Flush or pour-flush to:
 piped sewer system
 septic tank
 pit latrine
 Ventilated improved pit
latrine
 Pit latrine with slab
 Composting toilet

19. Unimproved sanitation
facilities
 Flush or pour-flush to
elsewhere
 (Excreta are flushed to the
street, yard or plot, open
sewer, a ditch, a drainage way
or other location)
 Pit latrine without slab or
open pit
 Bucket
 Hanging toilet or hanging
latrine
 No facilities or bush or field

20. Concepts of sustainability in sanitation
 The main objective of a
sanitation system is to protect
and promote human health
by providing a clean
environment and breaking
the cycle of disease.
 In order to be sustainable a
sanitation system has to be
not only economically viable,
socially acceptable and
technically and institutionally
appropriate, but it should
also protect the environment
and the natural resources.

22.  (1) Health: includes the risk of
exposure to hazardous
substances that could affect
public health at all points of
the sanitation system from
the toilet via the collection and
treatment system to the point
of reuse or disposal.
 The topic also covers aspects
such as hygiene, nutrition and
improvement of livelihood
achieved by the application of
a certain sanitation system, as
well as downstream effects.

23.  (2) Environment and natural
resources: involves the required
energy, water and other natural
resources for construction,
operation and maintenance of the
system, as well as the potential
emissions to the environment
resulting from use.
 It also includes the degree of
recycling and reuse practiced and
the effects of these, for example
reusing the wastewater, returning
nutrients and organic material to
agriculture, and the protecting of
other non-renewable resources, for
example through the production
of renewable energy (e.g. biogas or
fuel wood).

24.  (3) Technology and operation:
incorporates the functionality
and the ease with which the
system can be constructed,
operated and monitored using
the available human resources
(e.g. the local community,
technical team of the local utility
etc.).
 Furthermore, it evaluates the
robustness of the system, its
vulnerability towards disasters,
and the flexibility and
adaptability of its technical
elements to the
existing infrastructure, to
demographic and socio-economic
developments and climate
change.

25. Storm Water Drainage
 A storm drain is designed
to drain excess rain and ground water from paved
streets, parking lots, sidewalks, and roofs.
 Storm drains vary in design from small residential dry
wells to large municipal systems.

26. The stormwater drainage system is a route of drainage for
precipitation (rain or snow). Once the precipitation hits the
ground and starts to flow over land it is called runoff.

27. Inlet
 There are two main
types
of stormwater drain
(storm sewer) inlets:
side inlets and grated
inlets.
 Side inlets are located
adjacent to the curb
 Many inlets
have gratings or grids to
prevent people, vehicles,
large objects
or debris from falling
into the storm drain.

28. Piping
 Pipes can come in many
different cross-sectional
shapes (rectangular, square,
bread-loaf-shaped, oval,
inverted pear-shaped, and
most commonly, circular)
 Pipes made of different
materials can also be used,
such as brick, concrete, high-
density polyethylene or
galvanized steel. Fibre
reinforced plastic is starting to
see widespread use for drain
pipes and fittings.

29. Outlet
 Most drains have a single large
exit at their point of discharge
(often covered by a grating) into
a canal, river, lake, reservoir, sea
or ocean. Other than
catchbasins, typically there are
no treatment facilities in the
piping system.
 Storm drains may discharge
into man-made excavations
known as recharge basins or
retention ponds.

30. Reducing stormwater flows
 Runoff into storm sewers can be
minimized by including sustainable
urban drainage systems
 To reduce stormwater from
rooftops, flows from eaves troughs
(rain gutters and downspouts) may
be infiltrated into adjacent soil,
rather than discharged into the
storm sewer system.
 In many areas detention tanks are
required to be installed inside a
property and are used to
temporarily hold rainwater runoff
during heavy rains and restrict the
outlet flow to the public sewer