Septic Tanks _ SSWM

8/13/2019 Septic Tanks _ SSWM

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Concept Understand your System Planning & Process Tools Implementation Tools Specific Topics Backg

Home Implementation tools W astewater Treatment Hardware (Semi-)Centralised W astewater Treatments S eptic Tanks

Implementation Tools

Introduction

Water Sources

Water Purification

Water Distribution

Water Use

Wastewater Collection

WastewaterTreatment

Reuse and Recharge

Compiled by:

Septic Tanks

Dorothee Spuhler (seecon international

gmbh)

Executive SummaryA septic tankis an underground watertight chamber made of brick work,

concrete, fibreglass, PVC or plastic that receives both blackwaterfrom

cistern or pour-flush toiletsand greywaterthrough a pipe from inside a

building. Settlingand anaerobic digestionreduce solids and organics.

Septic tanks areprimary treatmentmethods, and the only moderately

treated effluentis infiltrated intothe ground or transported via a sewer.

Accumulating faecal sludgeneeds to be dug out the chamber and correctly

disposed regularly.

In Out

Blackwater, Brownwater, Excreta, (Organic

Solid Waste)Blackwater(settled), Faecal Sludge, (Biogas)

The septic tank is the most common small-scale decentralised treatment unit for grey water

and blackwaterfrom cistern or pour-flush toilets. It is basically a sedimentationtank (physical

treatment) in which settled sludge(solids and organics) is stabilisedby anaerobic digestion

(biological treatment). Dis solved and suspended (unsettleable) matter leaves the tank more or

less untreated. Its shape can be rectangular or cylindrical.

Septic tanks are used for wastewaterwith a high content of settleable solids, typically for

effluentfrom domestic sources, but they are also suitable for other wastewaterof similar

properties (SASSE 1998). Typical basic systemsincluding septic tanks at household or school

level are pourflush toilets, followed by two-chamber septic tanks and a soak pit, a leach field,

or an evapo-transpiration mound(www.schoolsanitation.org). In densely populated areas, on-

site inf iltration should not be used because the saturation of the soil with the only moderately

treated effluentcan cause a serious healthrisk. In these cases, septic tanks should be

connected to a simplified seweror solids-free sewerto transport the effluentsto a secondary

treatment(e.g. surface flow, horizontalor vertical flowconstructed wetlands). When septic

tanks are used as a primary settlingtreatment in DEWATSsystems, they are generally followed

by anaerobic filters, anaerobic baffled reactors(ABRs), constructed wetlands(planted gravel

filters) and maturation ponds. In any case, water is needed to pour and bring the wastes to the

septic tank (5 to 40 L of water per day per person, DFID2003).

Overview scheme of a septic tank. Solids settle out and undergo anaerobic digestion, the effluent

Related Topic

Sustainable Sanitati

Grasp what Sustaina

Sanitation actuallySustainable Sanitatio

Health and Hygiene

Background informat

health and hyg iene i

water management

sanitation.

Health and Hygiene I

Anaerobic Digestion

I f septic tanks are cl

biogas recovered, th

become anaerobic bi

settlers:

Biogas SettlerAnaerobic Digestion

Toilet Systems

Septic tank typically

blackwater from:pou

flush toilet; UD flush

flush

Pour-Flush ToiletFlush ToiletLow-flush ToiletUrine Diversion Flush

Effluent Infiltration

The effluent can eit

infiltrated on-site or

for fertigation, if is

heavely polluted. Ch

Soak PitsLeach FieldsFertigation

Faecal Sludge

Sludge that has been

settled in septic tan

called faecal sludge.

contains a lot of pat

and needs to be trea

before reuse. See al

Anaerobic DigestionDrying BedsSettling / Thickening(Co-)composting (La

Ads not by this s ite
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A septic tank asprimary treatment, followed by a leach field.

Source: U.S. EPA (n.y.)

Septic tank receiving black- and grey water from a housing (left)

and a septic tank collecting wastewaterfrom several housing as a

primary treatmentbefore a small bore sewersystem (right).

Sources: http-//cfpub.epa.gov/owm/septic/septic.cfm?

page_id=265 (left) and SANIMAS (2005) (right).

with suspended and dissolved pollutants flows through. A venting pipecan evacuate the biogas

formed during anaerobic digestion. Source: adapted from TILLEY et al. (2008).

Treatment Process and Basic Design Principles

A septic tank consis ts at minimum of 2 compartments made out of concrete or bricks. Pre-

fabricated concrete rings, PVC or fibreglass septic tanks are also available and may be less

expensive in some contexts (WSP2008). The first compartment occupies at least the half the

total volume, because most of the sludgeaccumulates here (SASSE 1998), while scum(oil and

fat) floats to the top. W hen there are only two chambers, the firs t one should be 2/3 of the

total length (TILLEY et a l. 2008). The following chamber(s) are provided to calm the turbulent

liquid. The baffle, or the separation between the chambers, is to prevent scumand solids from

escaping with the effluent(TILLEY et al. 2008). A T-shaped outlet pipe, the lower arm of which

dives 30 cm below water level (SASS E 1998), will further reduce the scumand solids that are

discharged. Normally, the chambers are all of the same depth (between 1.5 to 2.5 m), but

sometimes the first chamber is made deeper as the others.

Over time, anaerobicbacteriaand microorganismsstart to digest the settled sludge

anaerobically, transforming it into CO2 and CH4 (biogas) and some heat. Optimal physical

treatment by sedimentationtakes place when the flow is smooth and undisturbed. Biological

treatmentby anaerobic digestionis optimised by a quick and intensive contact between the

new inflow and old sludge, particularly when the flow is turbulent. Depending on the way the

new influentflows through the tank, different treatment effect predominate. With a turbulent

flow, the degradation of suspended and dissolved solids starts more quickly; however, more

suspended solids are discharged with the effluent. This leadsto bad odours, as active solids

that are not completely fermented leave the tank (SASSE 1998). The contact and hence

degradation is slower when the flow is less turbulent, but also less s uspended solids leave the

tank. The gases produced during anaerobic digestionmust be allowed to escape. If the

drainage system of the house or other building has a ventilationpipe at the upper end, gases

can escape from the septic tank along the drains. If the drainage system is not ventilated, a

screened vent pipe should be provided from the septic tank itself (WHO1992).The size of the first chamber

is calculated to be at least

twice the accumulating

sludgevolume. The sludge

volume depends on different

factors: the number of users;

the portion of settleable

solids of the influent; the

amount of water used per

capita; the average annual

temperatureand on de-

sludging intervals (SASS E

1998). Approximately 80 to

100 L should be provided per

domestic user (SASSE 1998),

but most countries provide a national standard for tank volume per domestic user. The

retention time should be designed for 48 hours to achieve at least a moderate treatment

(TILLEY et al. 2008). For help on dimensioning of septic tank, an exercise is given in

Eawag/Sandec (2008, Sanitation Systemsand Technologies. Exercise Septic Tank) and Excel

spreadsheets are available in SASSE (1998).

A septic tank will remove 30

to 50% of BOD(Biological

Oxygen Demand), 40 to 60%

of TSS(Total Suspended

Solids) (UNEP 2004) and

result in an abatement of 1

log units E. coli(afaecal

indicator bacteria) (TILLEY

et al. 2008) a lthough

efficiencies vary greatly

depending on the influent

concentrations and climatic

conditions. Hydraulic

Retention Times(HRT) are

generally 24 hours (MOREL &

DIENER 2006).

Aqua privyThe aqua privyis a variation of the septic tank and consists of a simple storage and settling

tank immediately under the latrine floor. Excretadrop directly into the tank through a pipe.

The bottom of the pipe is submerged in a liquid in the tank, forming a water sealto prevent

escape of flies, mosquitoes and smell (WHO1992). The tank functions like a septic tank. The

effluentusually infiltrates into the ground through a soak pit and accumulated solids (sludge)

must be removed frequently (WHO1992). In any case, the accumulating sludgemust be

treated.

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Toilet with aqua privyand soak pit. Source: WAaF (2002)

Costs considerations

Construction costs of septic tank are relatively low compared to other water based systems.

However, they are much more expensive than for dry or composting toiletsand unlikely to be

affordable by poorer people in society. They also require sufficient piped water to flush all the

wastes through the drains and manual or mechanical (vacuumorgulper) de-sludging needs tobe done periodically. Engineers mus t prepare design and layout, while unskilled labourers can

carry out construction if a mason supervises the work.

Operation and Maintenance

To start up a s eptic tank it should be "seeded" with sludgefrom a tank that has been operating

for some time to ensure that the necessary microorganismsresponsible for anaerobic

digestionare present (WHO1992).

Routine inspection is necessary to remove floating debris such as coarse materials and grease,

to ensure that there are no blockages at the inlet or outlet and to check whether de-sludging is

needed. De-sludging is needed when 1/2 to 2/3 of the total depth between the water level and

the bottom of the tank are occupied by sludgeand scum(WHO1992). One of the difficulties

with septic tanks is that when the tank is almost full of solids, the inflow scours a channel

through the sludgeand pass through the tank in a matter of minutes rather than remaining in

the tank for the required retention time (SASSE 1998). The most satisfactory method of sludge

removal is by vacuum tanker. If a vacuumtanker is not available, the sludgemust be bai led

out manuallyusing buckets or agulper. This is an unpleasant work and care must be taken to

ensure that sludgeis not spilled around the tank during emptying, as the removed sludgefrom

a septic tank includes fresh excrete and presents a risk of transmission of diseases of faecal

origin (TILLEY et al. 2008). Thefaecal sludgeneeds to be correctly disposed and further

treated (e.g. smallor large scalecomposting, anaerobic digestion). Before that, thefaecal

sludgecan also be further separated from the liquid in drying bedsor settling. The separated

effluentsfrom these s ystems should be treated in waste stabilisation ponds(WSP) or

constructed wetlands(surface flow, horizontalor vertical flow).

Generally, septic tanks should be emptied every 1 to 5 years. A small amount of sludgeshould

be left in the tank to ensure continuing rapid digestion. When opening the tank, gas produced

in anaerobic digestioncould escape and therefore, open fi re should be avoided when opening

the septic tank. Regular de-sludging activities require well-organised community or

public/private serv ice provider (TILLEY et al. 2008). Because of the delicate ecology, care

should also be taken not to discharge hars h chemicals into the septic tank (TILLEY et al. 2008).

Health Aspects

Since the effluentfrom septic tanks is anaerobic, it is likely to contain large numbers of

pathogens, which can be a potential source of infection (WHO1992). Many of the problems

with septic tank systems arise because no adequate consideration is given to the disposal of

the tank effluent. However, the entire tank is below the surface so direct contact of users with

any wastewateris avoided (TILLEY et al. 2008). But because of the microbial healthrisk which

arises from both the effluentand thefaecal sludgecare should be taken during inspections

and emptying. Mechanical emptying in a vacuum truckor a manual technology like a sludge

gulpercan decrease the healthrisks (TILLEY et al. 2008).

At a Glance

Working Principle

Basically a sedimentationtank (physical

treatment) in which settled sludgeis

stabilisedby anaerobic digestion(biological

treatment). Dissolved and suspended matter

leaves the tank more or less untreated.

Capacity/Adequacy

Household and community level; Primary

treatmentfor domestic grey- and

blackwater. Depending on the following

treatment, septic tanks can also be used for

industrial wastewater. Not adapted for areas

with highgroundwatertable or prone to
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flooding.

Performance

BOD: 30 to 50%; TSS: 40 to 60 %; E. coli: 1

log units

HRT: about 1 day

CostsLow-cost, depending on availability of

materials and frequency of de-sludging.

Self-help CompatibilityRequires expert design, but can be

constructed with locally available material.

O&M

Should be checked for water tightness , scum

and sludgelevels regularly. Sludgeneeds tobe dug out every 1 to 5 years and dis charged

properly (e.g. in compostingor drying bed).

Needs to be vented.

Reliability

When not regularly emptied, wastewater

flows through without being treated.

Generally good res istance to s hock loading.

Main strength Simple to construct and to operate.

Main weaknessEffluentand sludgerequire further

treatment. Long start-up phase.

ApplicabilitySeptic tanks can be installed in every type of climate, although the efficiency will be affected

in colder climates (TILLEY et al. 2008).

Septic tanks are used for wastewaterwith a high percentage of settleable solids, typically for

effluentfrom domestic sources (S ASSE 1998). They can be introduced as a decentralized, on-

site treatment system at household, block or school level(UNEP 2004). Effluentsstill contain

pathogensand should therefore not be used for crop irrigationnor should it be discharged to

canals or surface waterdrains (WHO1992). Effluentsform septic tanks can be soil infiltrated

in soak pits, a leach fieldor mounds. In more dense areas, the effluentsshould not be

infiltrated but the septic tank may be integrated as individual pre-treatment units for a

community into a small bore sewersystem transporting the wastewatersto a secondary

treatment. Even though the septic tank is watertight, it should not be constructed in areas

with highgroundwatertables or where there is frequent flooding (TILLEY et al. 2008).Aqua privies can be built indoors and above ground and are appropriate for rocky or flood

prone areas where pits or other technologies would not be appropriate, but they require

frequent emptying and constant maintenance (TILLEY et al. 2008).

AdvantagesCan be built and repaired with locally available materials

No real problems with f lies or odours if used correctly

Long service life

Little space required due to underground construction

Low investment costs, low operation and maintenance costs depending on the

availability of water and the requirement for emptying

No energy required

DisadvantagesHigh cost compared to dry or composting toilet systems

Constant and suff icient amounts of piped water required to bring the waste to the

treatment unit

Low reduction in pathogens, solids and organics: Secondary treatmentfor both

effluent and faecal sludge required

De-sludging required: Manual de-sludging is hazardous to health and mechanical de-

sludging (vacuum trucks) requires the infrastructure and may be rather costly

Only suitable for low-density housing in areas with low water table and not prone to

flooding

Manual cleaning of the tank is highly hazardous and an inhumane task, while

mechanical cleansing (vacuum trucks) requires sophisticated instruments

References

EAWAG/SANDEC (Editor) (2008): Sanitation Systems and Technologies. Exercises: Septic

Tank. Duebendorf: Swiss Federal Institute of Aquatic Science (Eawag), Department of Water

and Sanitation in Developing Countries (Sandec). PDF

http://www.sswm.info/sites/default/files/reference_attachments/EAWAG_SANDEC%202008%20Sanitation%20Systems%20and%20Tecnologies.%20Exercies%20Septic%20Tank.pdfhttp://www.sswm.info/library/228http://www.sswm.info/libraryhttp://www.sswm.info/glossary/2/letterg#term111http://www.sswm.info/glossary/2/letters#term964http://www.sswm.info/glossary/2/letterw#term1035http://www.sswm.info/glossary/2/letters#term970http://www.sswm.info/glossary/2/lettere#term143http://www.sswm.info/category/implementation-tools/reuse-and-recharge/hardware/recharge-and-disposal/leach-fieldshttp://www.sswm.info/category/implementation-tools/reuse-and-recharge/hardware/recharge-and-disposal/soak-pitshttp://www.sswm.info/glossary/2/lettere#term143http://www.sswm.info/glossary/2/letterw#term1336http://www.sswm.info/glossary/2/letters#term998http://www.sswm.info/glossary/2/letteri#term3096http://www.sswm.info/glossary/2/letterp#term389http://www.sswm.info/glossary/2/lettere#term143http://www.sswm.info/glossary/2/lettere#term143http://www.sswm.info/glossary/2/letterw#term1035http://www.sswm.info/glossary/2/letters#term976http://www.sswm.info/glossary/2/lettere#term143http://www.sswm.info/glossary/2/letterw#term1035http://www.sswm.info/glossary/2/letterd#term142http://www.sswm.info/glossary/2/letterc#term71http://www.sswm.info/glossary/2/letters#term976http://www.sswm.info/glossary/2/letters#term976http://www.sswm.info/glossary/2/letters#term963http://www.sswm.info/glossary/2/lettero#term382http://www.sswm.info/glossary/2/letterh#term188http://www.sswm.info/glossary/2/lettere#term144http://www.sswm.info/glossary/2/lettert#term1015http://www.sswm.info/glossary/2/letterb#term44


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WHO (Editor) (1992): A Guide to the Development of On-site

Sanitation. Geneva: World Health Organisation (WHO). URL[Accessed: 14.04.2010]. PDF

The publication presents appropriate technologies for sanitation

and highlights socio-economic aspects of planning and

implementing. Emphasis is g iven to household-level sanitation

improvements for urban areas, as well as rural areas and small

communities. Background information on sanitation, in-depth

technical information on the design, construction, operation and


http://www.sswm.info/sites/default/files/reference_attachments/WHO%201992%20A%20Guide%20to%20the%20development%20of%20on-site%20sanitation.pdfhttp://whqlibdoc.who.int/publications/1992/9241544430_eng.pdfhttp://www.sswm.info/library/214http://www.sswm.info/sites/default/files/reference_attachments/NATURGERECHTE%20TBW%202001%20Decentralised%20wastewater%20treatment%20methods%20for%20developing%20countries.pdfhttp://www.sswm.info/library/158http://www.sswm.info/sites/default/files/reference_attachments/ECOSAN%20CLUB%202012%20Faecal%20Sludge%20Management.pdfhttp://www.ecosan.at/ssphttp://www.sswm.info/library/6160http://www.sswm.info/sites/default/files/reference_attachments/IDAHO%20DEQ%202001%20A%20Homeowners%20Guide%20to%20Septic%20Systems.pdfhttp://www.deq.state.id.us/WATER/assist_citizen_comm/septic/septic_homeowners_guide.pdfhttp://www.sswm.info/library/33http://www.sswm.info/libraryhttp://www.sswm.info/sites/default/files/reference_attachments/WSP%202008%20Technology%20Options%20for%20Urban%20Sanitation%20in%20India.pdfhttp://www.wsp.org/UserFiles/file/Urban_Sanitation.pdfhttp://www.sswm.info/library/131http://www.sswm.info/sites/default/files/reference_attachments/WHO%201992%20A%20Guide%20to%20the%20development%20of%20on-site%20sanitation.pdfhttp://whqlibdoc.who.int/publications/1992/9241544430_eng.pdfhttp://www.sswm.info/library/214http://www.sswm.info/sites/default/files/reference_attachments/WAaF%202002%20Sanitation%20Technology%20Options.pdfhttp://www.sswm.info/library/219http://www.sswm.info/sites/default/files/reference_attachments/UNEP%202004%20Improving%20Municipal%20Wastewater%20Management%20in%20Coastal%20Cities.pdfhttp://esa.un.org/iys/docs/san_lib_docs/tsc_training_manual_wastewater_english.pdfhttp://www.sswm.info/library/225http://www.sswm.info/sites/default/files/reference_attachments/TILLEY%202008%20Compendium%20of%20Sanitation%20Systems%20and%20Technologies-FRENCH_0.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/TILLEY%202008%20Compendium%20of%20Sanitation%20Systems%20and%20Technologies_0.pdfhttp://www.eawag.ch/forschung/sandec/publikationen/indexhttp://www.sswm.info/library/34http://www.sswm.info/sites/default/files/reference_attachments/SASSE%201998%20DEWATS%20Decentralised%20Wastewater%20Treatment%20in%20Developing%20Countries_0.pdfhttp://www.sswm.info/library/129http://www.sswm.info/sites/default/files/reference_attachments/SANIMAS%202005%20Informed%20Choice%20Catalogue.pdfhttp://www.sswm.info/library/187http://www.sswm.info/sites/default/files/reference_attachments/MOREL%20and%20DIENER%202006%20Greywater%20Management.pdfhttp://www.eawag.ch/forschung/sandec/publikationen/ewm/dl/Morel_Diener_Greywater_2006.pdfhttp://www.sswm.info/library/649http://www.sswm.info/sites/default/files/reference_attachments/DFID%202003%20Handbook%20for%20the%20Assessment%20of%20Catchment%20Water%20Demand%20and%20Use.pdfhttp://www.hrwallingford.co.uk/downloads/projects/handbook_catchment_water.pdfhttp://www.sswm.info/library/224http://www.sswm.info/sites/default/files/reference_attachments/U.S%20EPA%20n.%20y.%20Planning%20for%20Septic%20Systems%20-%20Use%20of%20Online%20Decentralized%20Systems%20in%20Developing%20Areas.pdfhttp://www.epa.gov/owm/septic/pubs/planning_for_septic_systems.pdfhttp://www.sswm.info/library/223


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maintenance and project planning and development processes

involved in projects and programmes complement the book.

U.S.EPA (Editor) (1980): Onsite Wastewater Treatment Systems

Manual. United States Environmental Protection Agency, Office of

Water Office of Research and Development. PDF

Rather old design manual for onsite was tewater treatment options.

However, valuable information on established sys tems such as

septic tanks, sand filters, aerobic treatment units (suspended

growth and fixed film), disinfection, nutrient removal as well as

wastewater segregation and recycling are given. Additional

information is given on disposal methods and appurtenances.

UNEP (Editor); Murdoch University (Editor) (2004): Environmentallysound technologies in wastewater treatment for the implementation

of the UNEP/GPA "Guidelines on M unicipal Wastewater

Management". The Hague: United Nations Environment Programme

Global Programme of Action (UNEP/GPA), Coordination Office. PDF

Technical information on environmentally sound technologies in

wastewater treatment.

WSP (Editor) (2007): Philippines Sanitation Source Book and

Decision Aid. pdf presentation. Washington: Water and Sanitation

Program. PDFThis Sanitation Sourcebook distils some of the core concepts of

sanitation in a user-friendly format so that the book can serve as a

practical reference to sanitation professionals and investment

decision-makers, particularly the local governments. The annexe

contains a practical collection of factsheets on selected sanitation

system options.

WSP (Editor) (2008): Technology Options for Urban Sanitation in

India. A Guide to Decision-Making. pdf presentation. Washington:

Water and Sanitation Program. URL[Accessed: 26.03.2010]. PDF

These guidance notes are designed to provide state governments

and urban local bodies with additional information on available

technologies on sanitation. The notes also aid in making an

informed choice and explain the suitability of approaches.

MONVOIS, J.; GABERT, J.; FRENOUX, C.; GUILLAUME, M. (2010):

How to Select Appropriate Technical Solutions for Sanitation.

Cotonou and Paris: Partenariat pour le Dveloppement Municipal

(PDM) and Programme Solidarit Eau (pS-Eau). URL[Accessed:

19.10.2011]. PDF

The purpose of this guide is to assi st local contracting authorities

and their partners in identifying those sanitation technologies best

suited to the different contexts that exist within their town. The

first part of the guide contains aplanning process and a set of

criteria to be completed; these ass ist you in characterizing each

area of intervention so that you are then in a position to identify

the most appropriate technical solutions. The second part of the

guide consists of technical factsheets which give a practical

overview of the technical and economic characteristics, the

operating principle and the pros and cons of the 29 sanitation

technology options mos t commonly used in sub-Saharan Africa.See document in FRENCH

LEMOS CHERNICHARO, C.A. de (2007): Anaerobic Reactors.

London: International Water Association (IWA) Publishing. URL

[Accessed: 01.11.2013]. PDF

Anaerobic Reactors is the forth volume in the series Biological

Wastewater Treatment. The fundamentals of anaerobic treatment

are presented in detail, including its applicability, microbiology,

biochemistry and main reactor configurations. Two reactor types

are analysed in more detail, namely anaerobic filters and especially

UASB (upflow anaerobic sludge blanket) reactors. Particular

attention is also devoted to the post-treatment of the effluents

from the anaerobic reactors. The book presents in a clear and

informative way the main concepts, working principles, expected

removal efficiencies, design criteria, design examples,

construction aspects and operational guidelines for anaerobic

reactors.


http://www.sswm.info/sites/default/files/reference_attachments/LEMOS%20CHERNICHARO%202007%20Anaerobic%20Reactors.pdfhttp://www.iwawaterwiki.org/xwiki/bin/view/Articles/DevelopingCountriesTitlesfromIWAPublishingFreetoDownload?utm_source=WaterWiki+Connect&utm_campaign=81b910d928-wikinews_june13&utm_medium=email&utm_term=0_65bedfee7b-81b910d928-89879641http://www.sswm.info/library/8026http://www.sswm.info/sites/default/files/reference_attachments/MONVOIS%20et%20al%202010%20How%20to%20Select%20Appropriate%20Technical%20Solutions%20for%20Sanitation-FRENCH.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/MONVOIS%20et%20al%202010%20How%20to%20Select%20Appropriate%20Technical%20Solutions%20for%20Sanitation-ENGLISH_0.pdfhttp://www.pseau.org/outils/ouvrages/pdm_ps_eau_cms_guide_n_4_how_to_select_appropriate_technical_solutions_for_sanitation_2010.pdfhttp://www.sswm.info/library/4310http://www.sswm.info/sites/default/files/reference_attachments/WSP%202008%20Technology%20Options%20for%20Urban%20Sanitation%20in%20India.pdfhttp://www.wsp.org/UserFiles/file/Urban_Sanitation.pdfhttp://www.sswm.info/library/131http://www.sswm.info/sites/default/files/reference_attachments/WSP%202007%20Philippines%20sanitation%20sourcebook%20and%20decision%20aid.pdfhttp://www.sswm.info/library/130http://www.sswm.info/sites/default/files/reference_attachments/UNEP%202004%20ENVIRONMENTALLY%20SOUND%20TECHNOLOGIES%20in%20wastewater%20treatment.pdfhttp://www.sswm.info/library/229http://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%201980%20Onsite%20Wastewater%20Treatment%20and%20Disposal%20Systems.pdfhttp://www.sswm.info/library/324http://www.sswm.info/sites/default/files/reference_attachments/LEMOS%20CHERNICHARO%202007%20Anaerobic%20Reactors.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/MONVOIS%20et%20al%202010%20How%20to%20Select%20Appropriate%20Technical%20Solutions%20for%20Sanitation-ENGLISH_0.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/WSP%202008%20Technology%20Options%20for%20Urban%20Sanitation%20in%20India.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/WSP%202007%20Philippines%20sanitation%20sourcebook%20and%20decision%20aid.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/UNEP%202004%20ENVIRONMENTALLY%20SOUND%20TECHNOLOGIES%20in%20wastewater%20treatment.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%201980%20Onsite%20Wastewater%20Treatment%20and%20Disposal%20Systems.pdf


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SPERLING, M. von; LEMOS CHERNICHARO, C.A. de (2005):

Biological Wastewater Treatment in Warm Climate Regions Volume

1. London: International Water Association (IWA) Publishing. URL


Biological Wastewater Treatment in Warm Climate Regions gives a

state-of-the-art presentation of the s cience and technology of

biological wastewater treatment, particularly domestic s ewage.

The book covers the main treatment processes used worldwide

with wastewater treatment in warm climate regions given a

particular emphasis where simple, affordable and sustainable

solutions are required. The 55 chapters are divided into 7 parts

over two volumes: Volume One: (1) Introduction to wastewater

characteristics, treatment and disposal; (2) Bas ic principles of

wastewater treatment; (3) Stabilisation ponds; (4) Anaerobic

reactors; Volume Two (also available in the SSWM library): (5)

Activated sludge; (6) Aerobic biofilm reactors; (7) Sludge treatment

and disposal.

Case Studies

MOREL, A.; DIENER, S. (2006): Greywater treatment systems for

hotel premises, S ri Lanka. In: MOREL, A.; DIENER, S. (2006):

Greywater Management in Low and M iddle-Income Countries,

Review of different treatment systems for households or

neighbourhoods. Duebendorf, 80-84.

This case study presents different cost-effective on-site treatment

technologies with main focus on hotel greywater and blackwater

treatment systems. The first greywater treatment plant was

constructed for the Swiss Res idence Hotel. Based on the experience

gained by the Swiss Residence Hotel, further systems were

implemented at the hotels Ivy Banks and Coral Sands.

ROBBINS, D.; STRANDE, L.; DOCZI, J. (2012): Opportunities in

Fecal Sludge Management for Cities in Developing Countries:

Experiences from the Philippines. North Carolina: RTI International

. URL[Accessed: 15.01.2013]. PDF

In July 2012, a team from RTI International deployed to the

Philippines to evaluate four FSM programs with the goal of

reporting on best practices and lessons learned. The four cases

Dumaguete City, San Fernando City, Maynilad Water for the west

zone of metro Manila, and Manila Water from the east zone of

metro Manilawere chosen to highlight their different approaches

to implementing FSM.

Awareness Raising MaterialU.S. EPA (Editor) (1987): It's Your Choice: A Guidebook for Local

Officials on Small Community Wastewater Management Options .

United States Environmental Protection Agency, Office of Water

Office of Research and Development. PDF

This booklet was prepared by the United States Environmental

Protection Agency U.S. EPA for officials from communities of less

than 10000 people to present them available options and thus to

enable an informed choice.

U.S. EPA (Editor) (2000): Decentralized Systems Technology Fact

Sheet - Septic System Tanks. Washington, D.C.: United States

Environmental Protection Agency, Office of Water Off ice of

Research and Development (US EPA). URL[Accessed: 15.04.2010].

PDF

Four-page factsheet by the United States Environmental ProtectionAgency (U.S. EPA), describing septic tanks, their applicability and

the design of septic tank systems for household-level black and

greywater treatment.


Sheet - Septic Tank Leaching Chamber. Washington, D.C.: United

States Environmental Protection Agency, Office of W ater Office of

Research and Development.. URL[Accessed: 15.04.2010]. PDF

Seven-page factsheet by the United States Environmental Protection

Agency (U.S. EPA), describing the system, its applicability and the

design of a leaching field following a septic tank.


Sheet: Septic Tank Systems for Large Flow Application.

Washington, D.C.: United States Environmental Protection Agency,Office of Water Office of Research and Development.. URL


Ten-page factsheet by the United States Environmental Protection

Agency (U.S. EPA), describing the system, its applicability and

design of a septic tanks for large-flow applications.
http://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%202000%20Decentralized%20Systems%20Technology%20Fact%20Sheet-%20Septic%20Tank%20Systems%20for%20Large%20Flow%20Application.pdfhttp://www.epa.gov/owm/septic/pubs/septic_tank_large_flow_app.pdfhttp://www.sswm.info/library/217http://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%202000%20Decentralized%20Systems%20Technology%20Fact%20Sheet-%20Septic%20Tank%20Leaching%20Chamber%20.pdfhttp://nepis.epa.gov/Exe/ZyNET.exe/P1006DD9.TXT?ZyActionD=ZyDocument&Client=EPA&Index=2000+Thru+2005&File=D%3A%5CZYFILES%5CINDEX+DATA%5C00THRU05%5CTXT%5C00000022%5CP1006DD9.TXT&User=anonymous&Password=anonymous&ImageQuality=r85g16%2Fr85g16%2Fx150y150g16%2http://www.sswm.info/library/216http://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%202000%20Decentralized%20Systems%20Technology%20Fact%20Sheet-%20Septic%20System%20Tanks.pdfhttp://www.epa.gov/owm/mtb/septic_system_tank.pdfhttp://www.sswm.info/library/215http://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%201987%20%20%20It's%20Your%20Choice-%20A%20Guidebook%20for%20Local%20Officials%20on%20Small%20Community%20Wastewater%20Management%20Options%20.pdfhttp://www.sswm.info/library/262http://www.sswm.info/libraryhttp://www.sswm.info/sites/default/files/reference_attachments/ROBBINS%20et%20al.%202012%20Opportunities%20in%20Fecal%20Sludge%20Management%20for%20Cities%20in%20Developing%20Countries.%20Experiences%20from%20the%20Philippines.pdfhttp://www.eawag.ch/forschung/sandec/publikationen/ewm/dl/IWA_Water21_Philippines.pdfhttp://www.sswm.info/library/7133http://www.sswm.info/library/880http://www.sswm.info/libraryhttp://www.sswm.info/sites/default/files/reference_attachments/SPERLING%20and%20LEMOS%20CHERNICHARO%202005%20Biological%20Wastewater%20Treatment%20in%20Warm%20Climate%20Regions%20Volume%201.pdfhttp://www.iwawaterwiki.org/xwiki/bin/view/Articles/DevelopingCountriesTitlesfromIWAPublishingFreetoDownload?utm_source=WaterWiki+Connect&utm_campaign=81b910d928-wikinews_june13&utm_medium=email&utm_term=0_65bedfee7b-81b910d928-89879641http://www.sswm.info/library/232http://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%202000%20Decentralized%20Systems%20Technology%20Fact%20Sheet-%20Septic%20Tank%20Systems%20for%20Large%20Flow%20Application.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%202000%20Decentralized%20Systems%20Technology%20Fact%20Sheet-%20Septic%20Tank%20Leaching%20Chamber%20.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%202000%20Decentralized%20Systems%20Technology%20Fact%20Sheet-%20Septic%20System%20Tanks.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/US%20EPA%201987%20%20%20It's%20Your%20Choice-%20A%20Guidebook%20for%20Local%20Officials%20on%20Small%20Community%20Wastewater%20Management%20Options%20.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/ROBBINS%20et%20al.%202012%20Opportunities%20in%20Fecal%20Sludge%20Management%20for%20Cities%20in%20Developing%20Countries.%20Experiences%20from%20the%20Philippines.pdfhttp://www.sswm.info/sites/default/files/reference_attachments/SPERLING%20and%20LEMOS%20CHERNICHARO%202005%20Biological%20Wastewater%20Treatment%20in%20Warm%20Climate%20Regions%20Volume%201.pdf


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