SUSTAINABLE STRATEGIES IN WATER SUPPLY & SANITATION

Dr.K.MAHENDRAN,PROFESSOR & DIRECTOR i/c,

RURAL TECHNOLOGY CENTRE,GANDHIGRAM RURAL INSTITUTE – DEEMED

UNIVERSITY

IMPORTANCE OF WATER• Water is one of the most important substances on earth.

All plants and animals must have water to survive. If there was no water there would be no life on earth

• Apart from drinking it to survive, people have many other uses for water. These include: cooking – washing their bodies – washing clothes – washing cooking and eating utensilskeeping houses and

communities clean – recreation; such as swimming pools – keeping plants alive in gardens and parks

Different Sources of Water

• Water resources are divisible into two distinct categories :• the surface-water resources • the ground-water resources.

• Each of these categories is a part of the earth's water circulatory system, called the hydrologic cycle, and is derived from precipitation, which is rainfall plus snow.

HYDROLOGICAL CYCLE

DISTRIBUTE OF WATER ON EARTH

This is how the water is distribute on Earth. If you could see here that is most amount of water in the oceans.

POTABLE WATER

• Water that is safe for drinking is called Portable Water.

• It is most important that the water which people drink and use for other purposes is Clean water. This means that the water must be free of germs and chemicals and be clear (not cloudy).

SOME DOMESTIC USES OF WATER

WATER POLLUTION• Water pollution is the contamination of water bodies (e.g.

lakes, rivers, oceans, groundwater).

• Water pollution affects plants and organisms living in these bodies of water; and, in almost all cases the effect is damaging either to individual species and populations, but also to the natural biological communities.

• Water pollution occurs when pollutants are discharged directly or indirectly into water bodies without adequate treatment to remove harmful compounds.

Types of Water Pollution• Water pollution

– Any physical or chemical change in water that adversely affects the health of humans and other organisms

– Varies in magnitude by location

• Eight categories

– Sewage, disease-causing agents, sediment pollution, inorganic plant and algal nutrients, organic compounds, inorganic chemicals, radioactive substances, and thermal pollution

SEWAGE OIL SPILLING

IMPROVING WATER QUALITY-PURIFICATION FOR DRINKING WATER

• Treated water distributed to customers

• Sewer lines bring sewage to treatment plant

• Sewage treated at sewage treatment plant

SUSTAINABILITYThe maintenance of desired quantity and acceptable

quality standard of water supply services throughout the design life of the water supply systems may be defined as sustainability.

The sustainability is with reference to: • Source – quantity and quality• System – infrastructures

Factors affecting sustainability of water sources

• The depletion or lowering of water levels in groundwater and surface water sources

• Change/degradation of water quality due to over drawls or contamination by domestic/industrial wastes/ waste water

Elements of Sustainability• Source Sustainability: Ensuring availability of safe drinking

water in adequate quantity throughout the year

• System Sustainability: Optimizing the cost of production of water, devising proper protocol for O&M, building capacity of PRIs and awareness generation

• Financial Sustainability: Proper utilization of Finance Commission and O&M funds under NRDWP guidelines and recovering at least 50% cost through flexible methods devised by the local self government and improving energy efficiency

List of Ground, Surface and Roof water Harvesting Systems

• Gully plugs • Recharge Pit• Contour trench/bund• Semi-circular trenches on slopes• Check dam/Nala bund• Percolation pond/tank• Sub-surface dyke• Injection well• Recharge shaft• Roof water harvesting• Traditional water harvesting structures

SUPPORT MODEL FOR SELECTION OF SUSTAINABILITY STRUCTURES

1. Less than 20% of India’s rural population has access to safe & hygienic

sanitation facilities

2. An estimated 650 million Indians defecate in the open every day, and as a result

an estimated 200,000 tons of fecal matter are deposited in the open every day

3. Household waste on streets and in sewers

4. Unsanitary conditions in public toilets in urban areas

5. Industrial & Hazardous Waste on open land creating dump yards, and open

invitation for other types of wastes incl. medical wastes

6. Drinking Water not safe or hygienic in rural areas

7. Each year diarrhea kills over 500,000 people in India. Diseases such as Cholera,

Typhoid, Hepatitis, and Polio still occur in India in significant numbers

SANITARY CONDITIONS & CHALLENGES IN INDIA

DEFINITION OF SANITATION (WHO)

Sanitation generally refers to the provision of facilities and services for the safe

disposal of human urine and feces.

Inadequate sanitation is a major cause of disease world-wide and improving

sanitation is known to have a significant beneficial impact on health both in

households and across communities.

The word 'sanitation' also refers to the maintenance of hygienic conditions,

through services such as garbage collection and wastewater disposal.

STEPS TO SOLVE SANITATION PROBLEMS IN INDIA

1. Identify project area based on agreed upon priorities

2. Determine criteria & parameters to improve sanitation

3. Determine the population, demographics, needs of business and institutional

sector

4. Determine types of sanitation facilities required for each unique application

5. Determine feasible technologies for each application

6. Understand the role of local govt. NGOs, and volunteer organizations in the local

project area

7. Check applicable local regulations affecting each project

LIST OF TECHNOLOGIES CURRENTLY AVAILABLE FOR SANITATION AND TOILET SYSTEMS, GLOBALLY

1. Twin Pit (ventilated latrine) sanitation technology utilized by Sulabh

Technology

2. Pour Flush Latrines

3. Composting latrines

4. Aqua privies

5. AfriSan waterless technology

6. Vacu-tug technology

7. Portable plastic (polyethylene) toilets

8. Septic Tanks with drain fields

9. Sewerage collection and treatment systems

CRITERIA TO CONSIDER IN SELECTION OF VIABLE TECHNOLOGIES

1. Availability of water for sanitation & toilet systems

2. Availability of electricity or need for electrical generators

3. Vicinity to solid waste disposal facilities

4. Pick up service for liquid or semi-solid sanitary waste

5. Geological characteristics of local area, depth of seasonal high groundwater

level, soil density & porosity

6. The magnitude of sanitation facility needs (# of toilets reqd. , number of

customers to be served at normal and peak hours, services reqd. for large

institutions, schools, govt. buildings, community centers, etc. )

SUCCESS MODEL FOR SANITATION PROJECTSFOR PROMOTION OF GREENER ENVIRONMENT

Five ‘E’s

1. Environment - protect it

2. Energy - conserve it

3. Education & Awareness - promote it

4. Excellence in Innovation – practice it

5. Engage local govt, regulators, stakeholders, investors and consultants –

make informed & practically sound decisions for better quality of life that is

sustainable for generations

DEVELOPMENT OF A SUSTAINABLE & ECO-FRIENDLY SANITATION SYSTEM

Develop environmentally acceptable sanitation facilities (incl. toilet systems,

etc.) and install them so that they do not degrade living conditions or cause

unhygienic conditions

Provide wastewater treatment plants (incl . package plants) for larger

communities, institutions, schools, etc. with provision for water recycling

Develop adequate solid waste disposal facilities for wastewater sludges,

domestic waste vacuumed from dry toilets or other waste that has no other

uses.

Cont...

Ensure that water for drinking is kept separate from water used for toilets, to avoid

cross contamination.

Develop a system to regularly maintain the toilets and the wastewater systems to

prevent bad odors, flies, and other similar nuisances

Develop systems to encourage waste composting so that it can be converted to

fertilizers that can be used for agricultural applications.

Establish public awareness programs on sanitation & hygiene in all communities

that have existing or new sanitation facilities

STRATEGIES FOR ‘SANITATION PROJECT SUCCESS’ IN DEVELOPING COUNTRIES

Secure full understanding of local laws, regulations, policies procedures &

politics

Form alliances with local partners and stakeholders that can promote the

message of sanitation and hygiene in rural areas.

Provide technical solutions that are practical & sustainable in a local

economy, be a pioneer or innovator, not a follower

Try to utilize indigenous materials & products as much as possible, this will

create tangible benefits to local economy

Cont…

Work closely with regulators so that they fully understand the benefits of your

services and products

Make solutions more cost effective & efficient to implement, think “months

instead of years”.

Avoid middlemen and business brokers who might impede progress and inject

politics & corruption into decision making

Utilize motivational approaches to change sanitation behaviors in communities,

utilize ‘demand based’ approaches, with meaningful contributions by local

community members and end users of sanitation services

A Sanitary latrine should satisfy the following criteria

1. Surface soil should not be contaminated

2. Should not contaminate Surface water

3. Should not pollute ground water

4. Should be no handling of fresh excreta

5. Should not be accessible to flies and animals

6. Should be free from odors

7. Method /Technology should be simple, inexpensive and user friendly

Design of the pit - Factors

Bacteria play a major role in decomposing the excreta

Aerobic digestion – in the presence of Oxygen

Anaerobic digestion - in the absence of Oxygen ., -in the fluid

The final product is Nitrogen, Ammonia, Nitrites and Nitrates

Gases and salts leaches into the soil, Pathogens and ova are destroyed, Final

product is rich in Nutrient which is small in quantity

Effective Capacity of a wet pit latrines per person per year would be 37 liters or

1.4 cu.ft

The amount of sludge (wet) after one year digestion period per person would be 36.5liters (1.3cu.ft).Five member family require 185 Liters or 6.5 cu.ft per year

PIT

Circular pit -Square pit-Rectangular pitLined Pit

Open Joints –Bricks, Hollow blocks, Stone, Rings with holes, Bamboo, cut tree limbs with cement mortar. The pit may be Direct or Indirect with connected with pipes.

Simple Un lined Pit

Circular pits are suitable for unlined pit. But it should be shallow to avoid any wall collapse. Earthen mount will prevent run off water entering into the pit. Simple squatting platform with hole and lid may be useful to make the pit a sanitary one. It may be useful in a place where dry condition prevail

VENTILATED IMPROVED PIT (VIP)

1. A ventilated improved pit latrine (VIP) is similar to a single pit latrine with

addition of a vertical vent pipe.

2. Through the aeration in VIPs, odour and fly nuisances are reduced.

3. The VIP needs no water for its function.

4. Lining the pit prevents it from collapsing and provides support to the

superstructure.

5. Despite their simplicity, well‐designed single VIPs can be completely smell

free, and more to use than some other water‐based technologies.

Design considerations

1. The vent pipe should have an internal diameter of at least 110 mm and reach

more than 300mm above the highest point of the toilet superstructure.

2. It can be made out of PVC, bricks, pet bottles or iron pipes. Wind passing

over the top creates a suction pressure within the vent pipe and induces an air

circulation.

3. The vent works best in windy areas, but where there is little wind, its

effectiveness can be improved by painting the pipe black.

4. The heat difference between the pit (cool) and the vent (warm) creates an

updraft that pulls the air and odours up and out of the pit.

ADVANTAGES OF VIP LATRINE

1. Excavation of humus is easier than faecal sludge

2. Significant reduction in pathogens

3. Potential for use of stored faecal material as soil conditioner

4. Flies and odours are significantly reduced (compared to non‐ventilated pits)

5. Less chances for transmission of excreta related disease than lid or cover

6. Good health and hygiene practice

7. Can use as fertilizer after one year composting

8. Better life and environment

9. Construction and maintenance are easy

10. Suitable for water scarce area, as no need for water except occasional cleaning of the

squat plate

Disadvantages

1. VIPs are slightly more expensive than normal pit latrines.

2. Leachate can contaminate groundwater

3. No specific reuse of faeces and urine

4. Pits are susceptible to failure/overflowing during floods; stagnant water in pits

may promote insect breeding

5. Manual removal of humus is required

6. Possible contamination of groundwater

7. Higher capital costs than Single VIP; but reduced operating costs if self‐

emptied

RURAL PAN – COMMERCIAL PAN

DIFFERENCE LEACH PIT & SEPTIC TANK

ECO TOILET

ECO toilet is the type of dry toilet that uses a predominantly aerobic

processing system to treat human excreta. It is an alternate to flush

toilets.

Advantages – ECO TOILET

1. Water use reduction

2. Shock loading capacity

3. Odour problems Reduced

4. Lower household maintenance cost

5. End product recycled

6. Reduced grey water loading

7. Independence

8. Recycling

9. Unusual sites

Disadvantages - ECO TOILET

1. Construction

2. Maintenance

3. Management

4. Health Issues

5. Conditions

LEACH PIT RINGS

A mould is prepared in the interior of the squatting pan and trap. The cement and sand can be used to cast the plate and trap.

After setting, the pan and trap is cured.

The finished squatting pan and trap is transported to the site. The latrine slab- Circular/Square is cast with the squatting plate and trap is integral part of the slab Hardened and cure slab is placed over the pit.

The squatting plate and trap may be made fromCeramics, PVC, Cement, mosaic.

• The water dependent latrines can be further categorized on the basis of:• Flushing (pour flush or mechanical flush) ;Location of pit• onset type: if latrine room is just above the pit;• offset type: if pit is slightly offset from the latrine room;

• Water quantity required (pour flush latrine: where 1/2-2 liters of water is required for manual flushing;

• Excreta disposal system (pit latrine: where excreta is collected and decomposed within a pit; The pour flush latrine is a specially designed water-sealed bowl, which requires 1.5 - 2 liters of water for flushing the excreta.

• This water seal latrine eliminates entry of odor and prevents rodents to the latrine room from pit through the bowl. This pour flush latrine consists of a single pit either just below the bowl (onset type) or may be offset from the bowl (offset type) using the pour flush type bowl (pan and trap).

SELECTION CRITERIA FOR TECHNOLOGY

• Sustainability and lasting long-term benefits (impact);• immediate benefits (quality, convenience, reliability)• operation and maintenance;• Up gradibility, working life, eventual replacement possibilities;• cost-effectiveness (capital and recurrent costs and type of• materials requirements for construction); Affordability• accessibility• scope of up- gradibility• Local skilled workers• Sanitary latrine criteria• Soil conditions

WATER SEAL LATRINES

Pour-flush Toilets•It consists of a slab into which a special bowl is incorporated. The slab can be

fitted directly over a pit or slightly close to the pit.•The pit may be single or double•One to two liters of water is sufficient to flush the contents into the pit•Because of the water seal, there is no fly breeding•Odor can not escape out from the pit

The function of a water dependent latrine relies mainly on the usage ofwater. Without water these latrines fail to operate. The water flushes outexcreta from bowl, which consists of a water-seal generally known as atrap

RURAL PANS & TRAPS

The pan length = 450 mmThe slope is more than 45 degree

The water seal is 20mmThe passage for faeces is 750 mm

RURAL PANS & TRAPS

Rural Pans & Traps

PAN ABOVE THE PIT

ADVANTAGES OF PAN ABOVE THE PIT

•Odor free•Little chance for transmission of excreta related disease•Good health and hygiene practice•Appropriate where water is available•Long life time and no need to move for many years•Water requirements for flushing is low (1/2-2 liters)•Construction and maintenance are cheap and easy•Offset type can be adjusted in any type of dwelling without causingany smell nuisance•Suitable for less populated areas where space is available forrelocating the latrine•Possible to upgrade it into twin pit pour flush system (for offset type)

Special conditions – Soil and water Table

Block Cotton Soil Areas• The black cotton soils absorbs water and expands• The pit may collapse• The porosity of the soil is very low – leaching capacity is

low• Circular pit - lining with rings made up with cement and

sand• with re enforcement and holes for leaching• A coarse sand envelop around the pit – 10 cms to 20cms

OTHER FACTORS

• Privacy is one of the factors that determines the use of toilets in India

• The seats for male and female should be opposite direction• The doors should open inwards• The pans which is sticky or does not allow easy cleaning are

not accepted• Latrines designed for too large number of users not maintained

properly• One seated latrine is sufficient for a family• For camps, markets, community, one seat for every 25-30 is

needed • For schools one seat for every 20-25 Girls

SEPTIC TANKS

• It is costly • It is suitable for Institutions where group of people live

together• It has a covered settling tank where primary treatment takes

place• It requires secondary treatment. Therefore the effluent from

septic tank must be treated properly by a Dispersion trench or by a soak away pit. All this require land and money.

• Size of the tank has to be designed properly• It requires de sludging

Super structure continued User’s taste , affordability,local materials, durability, existing structures, privacy determine the superstructure.

Provide options for the usersExamples are Mud walls - plastered inside –Brick walls- cement

Hollow blocks Thatched wall and roof – leaves of Coconut and Palmarah Tiled roof – Mangalore tiles, cement tiles, asbestos sheet, tin roof,GI sheet Jute/Gunny cloths, flexi/ Rexin sheets, bamboo Hilly areas- slate stones - roof with slate of stones Ferro cement walls and roof Stone walls

RememberIt always better to use existing structure of the house for

superstructure

SUPER STRUCTURE

• Latrines are part of the house., It should adequately cared

• Only required water should be used for cleansing• No antiseptic/disinfectant should be used• No solid matters should be thrown in to the pan• Water seal must always filled with water• Platform should be dry• Adequate lighting and ventilation keeps latrine• Latrines gives privacy, promotes health of the

households• It helps you to save time and energy• It gives pride to family members and to the country

Thank you…