lesson 20: reuse of effluent...irrigation water; this is called «fertigation» (i.e., fertilization...

29.10.18, 14*41How Treatment Technologies Impact the Climate: Overview

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Lesson 20: Reuse of EffluentThe lesson will show possibilities for reuse of effluent produced in aWaste Water Treatment Plant and gives examples.

The reuse may include irrigation of gardens and agricultural fields orreplenishing surface water and groundwater (i.e., groundwaterrecharge). Reused water may also be directed toward fulfilling certainneeds in residences (e.g. toilet flushing), businesses, and industry, (andcould even be treated to reach drinking water standards).

Reclaiming water for reuse applications instead of using freshwater suppliescan be a water-saving measure. When used water is eventuallydischarged back into natural water sources, it can still have benefits toecosystems, improving streamflow, nourishing plant life and rechargingaquifers.

Wastewater reuse is a long-established practice used for irrigation,especially in arid countries. Reusing wastewater as part of sustainablewater management allows water to remain as an alternative water sourcefor human activities. This can reduce scarcity and alleviate pressures ongroundwater and other natural water bodies.

The following lesson describes some technologies, and give examples ofreuse:

Soak Pit

A soak pit, also known as a soakaway or leach pit, is a covered, porous-walled chamber that allows water to slowly soak into the ground.

Leach Field

A leach field, or drainage field, is a network of perforated pipes that are laidin underground gravel-filled trenches to dissipate the effluent from a water-

http://www.dis-course.net/index.php?id=4011




based Collection and Storage/Treatment or (Semi-) Centralized Treatmenttechnology.

Irrigation with Reused Water

To reduce dependence on freshwater and maintain a constant source ofwater for irrigation throughout the year, wastewater of varying quality canbe used in agriculture.

Waste Water Disposal / Groundwater Recharge

Treated effluent and/or stormwater can be directly discharged intoreceiving water bodies (such as rivers, lakes, etc.) or into the ground torecharge aquifers.

The lesson mentions also some practical examples from Jordan andthe legal framework in which these practical example are embedded.




29.10.18, 14*42How Treatment Technologies Impact the Climate: Soak Pit


Soak Pit

A soak pit, also known as a soakaway or leach pit, is a covered, porous-walled chamber that allows water to slowly soak into the ground. Pre-settled effluent from a Collection and Storage/Treatment or (Semi-)Centralized Treatment technology is discharged to the undergroundchamber from which it infiltrates into the surrounding soil.

As wastewater (greywater or blackwater after primary treatment) percolatesthrough the soil from the soak pit, small particles are filtered out by the soilmatrix and organics are digested by microorganisms. Thus, soak pits arebest suited for soil with good absorptive properties; clay, hard packed orrocky soil is not appropriate.

Design Considerations

The soak pit should be between 1.5 and 4 m deep, but as a rule of thumb,never less than 2 m above the groundwater table. It should be located at asafe distance from a drinking water source (ideally more than 30 m). Thesoak pit should be kept away from high-traffic areas so that the soil aboveand around it is not compacted.



It can be left empty and lined with a porous material to provide support andprevent collapse, or left unlined and filled with coarse rocks and gravel. Therocks and gravel will prevent the walls from collapsing, but will still provideadequate space for the wastewater. In both cases, a layer of sand and finegravel should be spread across the bottom to help disperse the flow. Toallow for future access, a removable (preferably concrete) lid should be usedto seal the pit until it needs to be maintained.

Appropriateness

A soak pit does not provide adequate treatment for raw wastewater and thepit will quickly clog. It should be used for discharging pre-settledblackwater or greywater.

Soak pits are appropriate for rural and peri-urban settlements.They dependon soil with a sufficient absorptive capacity. They are not appropriate forareas prone to flooding or that have high groundwater tables.

Health Aspects & Acceptance

As long as the soak pit is not used for raw sewage, and as long as theprevious Collection and Storage/Treatment technology is functioning well,health concerns are minimal. The technology is located underground and,thus, humans and animals should have no contact with the effluent.

Since the soak pit is odourless and not visible, it should be accepted by eventhe most sensitive communities.

Operation & Maintenance

A well-sized soak pit should last between 3 and 5 years withoutmaintenance. To extend the life of a soak pit, care should be taken toensure that the effluent has been clarified and/ or filtered to prevent theexcessive build-up of solids.

Particles and biomass will eventually clog the pit and it will need to be



cleaned or moved. When the performance of the soak pit deteriorates, thematerial inside the soak pit can be excavated and refilled.

29.10.18, 14*44How Treatment Technologies Impact the Climate: Leach Field


Leach Field

A leach field, or drainage field, is a network of perforated pipes that are laidin underground gravel-filled trenches to dissipate the effluent from a water-based Collection and Storage/Treatment or (Semi-) Centralized Treatmenttechnology.

Pre-settled effluent is fed into a piping system (distribution box and severalparallel channels) that distributes the flow into the subsurface soil forabsorption and subsequent treatment.

A dosing or pressurized distribution system may be installed to ensure thatthe whole length of the leach field is utilized and that aerobic conditions areallowed to recover between dosings. Such a dosing system releases thepressurized effluent into the leach field with a timer (usually 3 to 4 times aday).


Each trench is 0.3 to 1.5 m deep and 0.3 to 1 m wide. The bottom of eachtrench is filled with about 15 cm of clean rock and a perforated distribution



pipe is laid on top. More rock is placed to cover the pipe. A layer ofgeotextile fabric is placed on the rock layer to prevent small particles fromplugging the pipe. A final layer of sand and/or topsoil covers the fabric andfills the trench to the ground level.

The pipe should be placed at least 15 cm beneath the surface to preventeffluent from surfacing. The trenches should be dug no longer than 20 m inlength and at least 1 to 2 m apart. To prevent contamination, a leach fieldshould be located at least 30 m away from any drinking water source.

A leach field should be laid out such that it will not interfere with a futuresewer connection. The collection technology which precedes the leach field(e.g., septic tank) should be equipped with a sewer connection so that if, orwhen, the leach field needs to be replaced, the changeover can be done withminimal disruption.

Appropriateness

Leach fields require a large area and unsaturated soil with goodabsorptive capacity to effectively dissipate the effluent. Due to potentialover-saturation of the soil, leach fields are not appropriate for dense urbanareas. They can be used in almost every temperature, although there may beproblems with pooling effluent in areas where the ground freezes.

Homeowners who have a leach field must be aware of how it works and oftheir maintenance responsibilities. Trees and deep-rooted plants should bekept away from the leach field as they can crack and disturb the tile bed.


Since the technology is underground and requires little attention, users willrarely come in contact with the effluent and, therefore, it has no health risk.

The leach field must be kept as far away as possible (at least 30 m)from any potential potable water source to avoid contamination.




A leach field will become clogged over time, although this may take 20 ormore years, if a well-maintained and well-functioning primary treatmenttechnology is in place. Effectively, a leach field should require minimalmaintenance; however, if the system stops working efficiently, the pipesshould be cleaned and/or removed and replaced.

To maintain the leach field, there should be no plants or trees on it.There should also be no heavy traffic above it because this could crush thepipes or compact the soil.

29.10.18, 14*46How Treatment Technologies Impact the Climate: Irrigation


Irrigation with Reused Water

To reduce dependence on freshwater and maintain a constant source ofwater for irrigation throughout the year, wastewater of varying qualitycan be used in agriculture. However, only water that has had secondarytreatment (i.e., physical and biological treatment) should be used to limitthe risk of crop contamination and health risks to workers.

There are two kinds of irrigation technologies appropriate for treatedwastewater:

1. Drip irrigation above or below ground, where the water is slowlydripped on or near the root area; and

2. Surface water irrigation where water is routed over-land in a series ofdug channels or furrows.

To minimize evaporation and contact with pathogens, spray irrigationshould be avoided. Properly treated wastewater can significantly reducedependence on fresh water, and/or improve crop yields by supplyingincreased water and nutrients to plants.



Raw sewage or untreated blackwater should not be used, and even well-treated water should be used with caution. Long-term use of poorly orimproperly treated water may cause long-term damage to the soil structureand its ability to hold water.


The application rate must be appropriate for the soil, crop and climate, or itcould be damaging. To increase the nutrient value, urine can be dosed intoirrigation water; this is called «fertigation» (i.e., fertilization + irrigation).

The dilution ratio has to be adapted to the special needs and resistance ofthe crop. In drip irrigation systems care should be taken to ensure thatthere is sufficient head (i.e., pressure) and maintenance to reduce thepotential for clogging (especially, with urine from which struvite willspontaneously precipitate).

Appropriateness

Generally, drip irrigation is the most appropriate irrigation method; it isespecially good for arid and drought prone areas. Surface irrigation is proneto large losses from evaporation but requires little or no infrastructure andmay be appropriate in some situations.

Crops such as corn, alfalfa (and other feed), fibres (e.g., cotton),trees, tobacco, fruit trees (e.g., mangos) and foods requiringprocessing (e.g., sugar beets) can be grown safely with treatedeffluent. More care should be taken with fruits and vegetables that may beeaten raw (e.g., tomatoes) because they could come in contact with thewater. Energy crops like eucalyptus, poplar, willow, or ash trees can begrown in short-rotation and harvested for biofuel production. Since thetrees are not for consumption, this is a safe, efficient way of using lower-quality effluent.

Soil quality can degrade over time (e.g., due to the accumulation of salts) ifpoorly treated wastewater is applied. Despite safety concerns, irrigation



with effluent is an effective way to recycle nutrients and water.


Appropriate treatment (i.e., adequate pathogen reduction) should precedeany irrigation scheme to limit health risks to those who come in contactwith the water. Furthermore, it may still be contaminated with the differentchemicals that are discharged into the system depending on the degree oftreatment the effluent has undergone.

When effluent is used for irrigation, households and industries connected tothe system should be made aware of the products that are and are notappropriate to discharge into the system. Drip irrigation is the only type ofirrigation that should be used with edible crops, and even then, careshould be taken to prevent workers and harvested crops fromcoming in contact with the treated effluent.

The WHO guidelines on wastewater (see section «Further Resources») usein agriculture should be consulted for detailed information and specificguidance.


Drip irrigation systems must be periodically flushed to avoid biofilm growthand clogging from all types of solids. Pipes should be checked for leaks asthey are prone to damage from rodents and humans. Drip irrigation is morecostly than conventional irrigation, but offers improved yields anddecreased water/operating costs.

Workers should wear appropriate protective clothing.

29.10.18, 14*47How Treatment Technologies Impact the Climate: Disposal & Recharge


Water Disposal & GroundwaterRecharge

Treated effluent and/or stormwater can be directly discharged intoreceiving water bodies (such as rivers, lakes, etc.) or into the ground torecharge aquifers.

The use of the surface water body, whether it is for industry, recreation,spawning habitat, etc., will influence the quality and quantity of treatedwastewater that can be introduced without deleterious effects.

Alternatively, water can be discharged into aquifers. Groundwater rechargeis increasing in popularity as groundwater resources deplete and assaltwater intrusion becomes a greater threat to coastal communities.Although the soil is known to act as a filter for a variety of contaminants,groundwater recharge should not be viewed as a treatmentmethod.

Once an aquifer is contaminated, it is next to impossible toreclaim it.


It is necessary to ensure that the assimilation capacity of the receivingwater body is not exceeded, i.e. that the receiving body can accept thequantity of nutrients without being overloaded. Parameters such asturbidity, temperature, suspended solids, BOD, nitrogen and phosphorus(among others) should be carefully controlled and monitored beforereleasing any water into a natural body. Local authorities should beconsulted to determine the discharge limits for the relevant parameters asthey can widely vary. For especially sensitive areas, a post-treatmenttechnology (e.g. chlorination) may be required to meet microbiologicallimits.

29.10.18, 14*47How Treatment Technologies Impact the Climate: Disposal & Recharge


The quality of water extracted from a recharged aquifer is a function of thequality of the wastewater introduced, the method of recharge, thecharacteristics of the aquifer, the residence time, the amount of blendingwith other waters and the history of the system. Careful analysis of thesefactors should precede any recharge project.

Appropriateness

The adequacy of discharge into a water body or aquifer will entirely dependon the local environmental conditions and legal regulations. Generally,discharge to a water body is only appropriate when there is a safe distancebetween the discharge point and the next closest point of use. Similarly,groundwater recharge is most appropriate for areas that are at risk ofsaltwater intrusion or aquifers that have a long retention time.

Depending on the volume, the point of discharge and/ or the quality of thewater, a permit may be required.


Generally, cations (Mg2+, K+, NH4+) and organic matter will be retainedwithin a solid matrix, while other contaminants (such as nitrates) willremain in the water. There are numerous models for the remediationpotential of contaminants and microorganisms, but predicting downstreamor extracted water quality for a large suite of parameters is rarely feasible.Therefore, potable and non-potable water sources should be clearlyidentified, the most important parameters modelled and a risk assessmentcompleted.


Regular monitoring and sampling is important to ensure compliance withregulations and to ensure public health requirements. Depending on therecharge method, some mechanical maintenance may be required.

29.10.18, 14*48How Treatment Technologies Impact the Climate: Risk Factors


Risks of Reusing TreatedEffluent

Food and water security is a growing global challenge especially formarginal environments such as the Middle East and North Africa regionwhich receives a mere 1.3% of the world’s renewable freshwater but has thehighest population growth rate in the world. These factors, along with theprojected effects of climate change, have put enormous pressure onagriculture to reduce its share of freshwater use and look for alternativesources to meet the requirements.

Treated municipal wastewater is a useful option for farm productionsystems as it contains organic matter and nutrients which are essential forplant growth. However, its use needs careful handling to mitigate itsdetrimental effects on soils, crops and human health.

Risks of reusing treated wastewater

The volume of wastewater generated by domestic, industrial and



commercial sources has increased with population, urbanization, improvedliving conditions, and economic development. The productive use of treatedwastewater has also increased, as worldwide millions of small-scale farmersin urban and peri-urban areas depend on wastewater or wastewaterpolluted water sources to irrigate high-value edible crops for urban markets,often as they have no alternative sources of irrigation water.

Undesirable constituents in wastewater can harm human health and theenvironment. Hence, wastewater irrigation is an issue of concern to publicagencies responsible for maintaining public health and environmentalquality. Therefore in the near term, risk management and interim solutionsare needed to prevent adverse impacts from wastewater irrigation. Acombination of source control, and farm-level and post-harvest measurescan be used to protect farm workers and consumers. The WHO guidelinesrevised in 2006 for wastewater use suggest measures beyond the traditionalrecommendations of producing only industrial or non-edible crops.

On the other hand side, there is a global trend towards a lack of socialacceptance with regards to reusing safely treated (according to localstandards) wastewater. In addition, the need for substituting the globallyrising freshwater demand with safely treated wastewater is growing.

As a result, the following general needs can be highlighted:

Improved policiesInstitutional dialoguesFinancial mechanismsReasonable effluent standards (taylor made for the local context)combined with incentives or enforcement to motivate forimprovements in water management by household and industrialsectors discharging wastewater from point sources.Segregation of chemical pollutants from urban wastewater facilitatestreatment and reduces risk.Strengthening institutional capacity and establishing links betweenwater delivery and sanitation sectors through inter-institutional



coordination leads to more efficient management of wastewater andrisk reduction of reusing treated wastewater in different sectors.

29.10.18, 14*49How Treatment Technologies Impact the Climate: Opportunities


Opportunities of ReusingTreated EffluentReusing of treated WW in industries

Reusing water in industry has the potential to reduce the costs of watersupply and wastewater treatment by industries and reduces pressure onwater resources. Wastewater can be reused within a business itself, orbetween several businesses through industrial symbiosis. Depending on thetype and quality of the wastewater, it may either be reused directly, ortreated before reuse (i.e. recycled). The different technologies available fordirect reuse as well as decentralised wastewater treatment for wastewaterrecycling are summarised in a factsheet (in further resources).

Reusing of treated WW on a household level

Domestic water use represents a growing proportion of global water use.Water use optimisation means resistance to chronic and short-term waterscarcity and cost and energy savings for water supply and wastewatertreatment as less water is required and less polluted water produced.Besides installing water saving appliances, source separation and reuse ofdifferent types of wastewater is a way to optimise water use at home.Depending on the type, quality and quantity of water, wastewater can eitherbe reused directly, or treated and reused (recycled).

Reusing of treated WW in agriculture

Refer to the next page of this lesson (Agricultural Sector in Jordan) wherethe use of treated wastewater in the agricultural sector is elaborated indetail.

Reusing treated WW in Europe

In Europe the last two decades has witnessed growing water stress, both interms of water scarcity and quality deterioration, which has prompted many



29.10.18, 14*49How Treatment Technologies Impact the Climate: Opportunities


municipalities to look for a more efficient use of water resources, includinga more widespread acceptance of water reuse practices.

The paper for further readings (Resources) reviews European water reusepractices and sets out the map of the water reclamation technologies andreuse applications. The preliminary evaluation indicates that for anincreased utilisation of reclaimed wastewater, clearer institutionalarrangements, more dedicated economic instruments and the set-up ofwater reuse guidelines are needed. Technological innovation and theestablishment of a best practice framework will help, but even more, achange is needed in the underlying stakeholders’ perception ofthe water cycle.

Opportunities for Jordan

Jordan is a nation burdened with extreme water scarcity that has alwaysbeen one of the biggest barriers to its economic growth and development.This water crisis situation has been aggravated by a populationincrease that has doubled in the last two decades alone because ofrefugees fleeing to Jordan from neighbouring countries. The transboundaryand climate change issues affecting Jordan’s water supplies have to also betaken into consideration.

The following graph from the National Water Strategy (2015 – 2025) ofJordan shows that treated wastewater is a valuable resource with thepossibility to grow in terms of volume whereas surface water, non-renewable groundwater and groundwater safe yield is projected to stay thesame or even decline.


29.10.18, 14*50How Treatment Technologies Impact the Climate: Agricultural Sector in Jordan


Reuse of Treated Effluent in theAgricultural SectorTreated wastewater is considered a beneficial source added to water stockthat can be reused in restricted agriculture and other purposes (notdomestic), including groundwater recharge, and this is required, andfeasible in the light of arid and semi-arid climate and modest per capitaFresh water resources. Because of the huge imbalance in the population, theTWW effluent is added to the water stock for use in irrigated agriculture. Itwill constitute a substantial percentage of the irrigation water in future.[Taken from National Water Strategy (2015 – 2025) for Jordan]

The agricultural sector in Jordan can be perceived as one of the mostproductive sectors which is not only considered a source of income, but alsoa way of life, a system of national food security, social hub and in such a wayrelated to rural development of the country.

Jordan is one of the most water deprived countries in terms of fresh waterresources. The production of food in semi-arid countries like Jordan ishardly possible without irrigation (91% of the kingdom area receives lessthan 200 mm of rain fall). Hence, the agricultural sector in Jordan is highlydependent on irrigation of its products. On the other hand, the agriculturalsector offers a high number of job opportunities in food production andother support services.

Advantages of using treated wastewater in the agricultural sector

Availability of treated wastewater all over the year as a stable sourcefor irrigation.Increase of productivity for agricultural crops due to the availability ofnutrients from the treated wastewater. These nutrients are beneficialand necessary for a better plant growth and can substitute the use ofchemical fertilizer.Substitution of freshwater for irrigation with treated wastewater leaves

29.10.18, 14*50How Treatment Technologies Impact the Climate: Agricultural Sector in Jordan


the scarce fresh water sources for more essential purposes such as theprovision of drinking water.Cost savings due to the reduction of using chemical fertilizer and usingmore organic fertilizer.

Reuse of treated wastewater in the agricultural sector is about 131 MCM(Year 2015) which states around 51% of the water use in the country:

29.10.18, 14*53How Treatment Technologies Impact the Climate: Further Resources


Further ResourcesYou now have a rough understanding of the problems and conceptsdiscussed in this lesson. While the previous pages gave an overview, thefollowing resources are now meant to «dive deeper» and to learn more.

The resources offered here are carefully selected. The occupation which thepapers, videos, etc. raised here is therefore essential to complete this lessonsuccessfully

Video

Reuse of treated wastewater in irrigation in Jenin- Palestine

2016: Reuse of treated wastewater in irrigation in Jenin-Palestine, 14:00 min, (Arabic)

This short video documents a three year project for installing a waterdistribution network to use treated waste water in irrigating fodder crops

https://www.youtube.com/watch?v=jqeDRrL6dTI

https://www.youtube.com/channel/UC9QN9rnYqGHFHtpBOkGEIxg



and fruit trees. It is meant to share knowledge gained duringimplementation with interested people.

3.6 Use and/or Disposal - E<uent and Other Products

EAWAG: Planning & Design of Sanitation Systems andTechnologies, 2016. 8 min

Use and/or Disposal - Effluent and Other Products

DocumentsWHO (2006). Guidelines for the Safe Use of Wastewater, Excretaand Greywater. Volume 2: Wastewater Use in Agriculture. WorldHealth Organization, Geneva, CH.

Discussion of health aspects of wastewater use and of good irrigationpractice in Annex 1

https://www.youtube.com/watch?v=s04aVKJKbb0

https://www.youtube.com/channel/UCgHWg270mPystIe5rVFOvCA



[click the image to open the PDF (15mb,222p pages)]

Oxfam (2008): Septic TankGuidelines. Technical Brief.Oxfam GB, Oxford, UK. PDF, 4pages

A septic tank takes raw sewage in,allows the solids to settle (sludge)and allows the remaining liquid toflow into the surrounding soil bymeans of a soakaway. Scum on thesurface is also prevented fromleaving the tank. Microorganisms inthe anaerobic environment in thetank digest the sludge and scum. Thesystem consists of several stages,supply to the tank, the tank itself andthe soak field. Septic tanks takesewage (grey water - washing andhousehold waste and black water -sewage from latrines,) but notrainwater. Sludge volume is reducedby microbial action but still needsperiodic emptying. Septic tanksprovide partial treatment ofwastewater. The soakfield providessecondary treatment in the form ofsubsoil infiltration. Septic tanks aresuitable for conditions where thewastewater can drain away and beabsorbed into the soil withoutcontaminating ground water whereit is extracted. Sealed solid wastestorage is an option if soil isunsuitable or the water table is too high. Cesspits are another option.

http://www.dis-course.net/fileadmin/climate_impact/resources/tbn9-septic-tank-guidelines.pdf

http://www.dis-course.net/fileadmin/climate_impact/resources/WHO-Guidelines_Vol2-eng.pdf



[click the image to open the PDF (1.0mb, 55pages)]

FAO (2012): On-Farm Practicesfor the Safe Use of Wastewaterin Urban and Peri-UrbanHorticulture. A TrainingHandbook for Farmer FieldSchools.

IWA (2017/18): The reuseOpportunity – WastewaterReport 2018

This report aims to illustrate thewastewater challenge and reuseopportunity in eight cities across theglobe, presenting a reuse roadmapand identifying priorities and ben-efits to meeting SDG target 6.3. Thecities profiled in this report are notthe ‘usual suspects’ of pioneeringcities who have been on thistrajectory for some time, but rathercities small and large fromdeveloping countries where theexisting and future challenges arefelt more acutely and the need forchange is pressing.

SSWM 2018: Wastewater Reusein Industry

Reusing water in industry has thepotential to reduce the costs of watersupply and wastewater treatment by

http://www.dis-course.net/fileadmin/climate_impact/resources/L20-FFS_Handbook_low.pdf

http://www.dis-course.net/fileadmin/climate_impact/resources/L20_IWA_Wastewater-report-2017.pdf



[click the image to open the PDF (10mb, 24pages)]

[click the image to open the PDF, 9 pages]

industries and reduces pressure onwater resources. Wastewater can bereused within a business itself, orbetween several businesses throughindustrial symbiosis. Depending onthe type and quality of thewastewater, it may either be reuseddirectly, or treated before reuse (i.e.recycled). The different technologiesavailable for direct reuse as well asdecentralised wastewater treatmentfor wastewater recycling aresummarised in this factsheet.

SSWM 2018: Wastewater Reuseat Home

Domestic water use represents agrowing proportion of global wateruse. Water use optimisation meansresistance to chronic and short-termwater scarcity and cost and energysavings for water supply andwastewater treatment as less wateris required and less polluted waterproduced. Besides installing watersaving appliances, source separationand reuse of different types ofwastewater is a way to optimisewater use at home. Depending on thetype, quality and quantity of water,wastewater can either be reuseddirectly, or treated and reused

http://www.dis-course.net/fileadmin/climate_impact/resources/Wastewater_Reuse_at_Home_-_SSWM.pdf

http://www.dis-course.net/fileadmin/climate_impact/resources/Wastewater_Reuse_in_Industry_-_SSWM.pdf





(recycled). This factsheetsummarises the variety of technical options for wastewater treatment,reuse, as well as reuse possibilities for organic waste at the householdlevel.

D. Bixio et al., 2006,Elsevier: Wastewater reuse inEurope

In Europe the last two decades haswitnessed growing water stress,both in terms of water scarcity andquality deterioration, which hasprompted many municipalities tolook for a more efficient use of waterresources, including a morewidespread acceptance of waterreuse practices. This paper reviewsEuropean water reuse practices andsets out the map of the waterreclamation technologies and reuseapplications. The data are based ona conventional literature survey, on the preliminary evaluation of an in-depth survey of a large number of European water reuse projects and onthe findings of a dedicated international workshop. The preliminaryevaluation indicates that for an increased utilisation of reclaimedwastewater, clearer institutional arrangements, more dedicated economicinstruments and the set-up of water reuse guidelines are needed.Technological innovation and the establishment of a best practiceframework will help, but even more, a change is needed in the underlyingstakeholders’ perception of the water cycle.

Kretschmer et al. 2006: Wastewater Reuse for Agriculture

http://www.dis-course.net/fileadmin/climate_impact/resources/wastewater_reuse_in_europe.pdf




The present paper is based on aliterature review and aims to tacklethe most important aspectsregarding the topic wastewaterreuse with some recent examples,focusing on reuse in agriculture. Stillin some countries the institutionaland legal framework is weak or notexistent or only referring tointernational standards (guidelinesor laws) which are very general andmost of the times demand very costintensive solutions. An integratedplanning approach is thereforenecessary in case reuse ofwastewater shall be onemanagement alternative in a waterstressed basin. Here the technological, economical and health aspect aswell as the legal framework have to be considered. Therefore reuse ofwater is an interdisciplinary challenge for the present and for the future.

http://www.dis-course.net/fileadmin/climate_impact/resources/KRETSCHMER_et_al._2006_Wastewater_Reuse_for_Agriculture.pdf



Lesson 21: Reuse of SludgeThe lesson will show possibilities for reuse of products from sludgetreatment processes and give examples.

Sewage sludge treatment describes the processes used to manage anddispose of sewage sludge produced during sewage treatment. Sludge ismostly water with lesser amounts of solid material removed from liquidsewage. Primary sludge includes settleable solids removed during primarytreatment in primary clarifiers. Secondary sludge separated in secondaryclarifiers includes treated sewage sludge from secondary treatmentbioreactors.

The choice of a sludge treatment method depends on the volume of sludgegenerated, and comparison of treatment costs required for availabledisposal options. Air-drying and composting may be attractive to ruralcommunities, while limited land availability may make anaerobicdigestion and mechanical dewatering preferable for cities, andeconomies of scale may encourage energy recovery alternatives inmetropolitan areas.

Reducing sludge volume may increase the concentration of some toxicchemicals in the sludge.

The following lesson describes some of the uses of treatment sludge, suchas:

Surface Disposal & Storage

Surface disposal refers to the stockpiling of sludge, faeces or other materialsthat cannot be used elsewhere. Once the material has been taken to asurface disposal site, it is not used later. Storage refers to temporarystockpiling. It can be done when there is no immediate need for thematerial and a future use is anticipated, or when further pathogen reductionand drying is desired before application.




Application of Sludge

Depending on the treatment type and quality, digested or stabilized sludgecan be applied to public or private lands for landscaping or agriculture.

The lesson also mentions Practical examples and the Legal Frameworkin Jordan



29.10.18, 14*55How Treatment Technologies Impact the Climate: Disposal & Storage


Surface Disposal & Storage ofSludge

Surface disposal refers to the stockpiling of sludge, faeces or othermaterials that cannot be used elsewhere. Once the material has beentaken to a surface disposal site, it is not used later. Storage refers totemporary stockpiling. It can be done when there is no immediate need forthe material and a future use is anticipated, or when further pathogenreduction and drying is desired before application.

This technology is primarily used for sludge, although it is applicable forany type of dry, unusable material. One application of surface disposal is thedisposal of dry cleansing materials, such as toilet paper, corn cobs, stones,newspaper and/or leaves. These materials cannot always be included alongwith other water-based products in some technologies and must beseparated. A rubbish bin should be provided beside the User Interface tocollect the cleansing materials and menstrual hygiene materials. Drymaterials can be burned (e.g., corn cobs) or disposed of along with thehousehold waste. For simplicity, the remainder of this technology



information sheet will be dedicated to sludge since standard solid wastepractices are beyond the scope of this course.

When there is no demand for or acceptance of the beneficial use of sludge, itcan be placed in monofills (sludge-only landfills) or heaped into permanentpiles. Temporary storage contributes to further dehydration of the productand the die-off of pathogens before it is used.


Landfilling sludge along with municipal solid waste (MSW) is not advisablesince it reduces the life of a landfill, which has been specifically designed forthe containment of more noxious materials. As opposed to more centralizedMSW landfills, surface disposal sites can be situated close to where thesludge is treated, limiting the need for long transport distances.

The main difference between surface disposal and land application is theapplication rate. There is no limit to the quantity of sludge that can beapplied to the surface since nutrient loads or agronomic rates are not aconcern. Attention must be paid, however, to groundwater contaminationand leaching. More advanced surface disposal systems may incorporate aliner and leachate collection system in order to prevent nutrients andcontaminants from infiltrating the groundwater.

Sites for the temporary storage of a product should be covered to avoidrewetting by rainwater and the generation of leachate.

Appropriateness

Since there are no benefits gained from surface disposal, it should not beconsidered as a primary option. However, where sludge use is not easilyaccepted, the contained and controlled stockpiling of solids is far preferableto uncontrolled dumping. Storage may in some cases be a good option tofurther dry and sanitize a material and to generate a safe, acceptableproduct. Storage may also be required to bridge the gap between supply anddemand.



Surface disposal and storage can be practiced in almost every climate andenvironment, although they may not be feasible where there is frequentflooding or where the groundwater table is high.


If a surface disposal and storage site is protected (e.g., by a fence) andlocated far from the public, there should be no risk of contact or nuisance.The contamination of groundwater resources by leachate should beprevented by adequate siting and design.

Care should be taken to protect the disposal or storage site from vermin andpooling water, both of which could exacerbate smell and vector problems.


Staff should ensure that only appropriate materials are disposed of at thesite and must maintain control over the traffic and hours of operation.


29.10.18, 15*02How Treatment Technologies Impact the Climate: Application


Application of Sludge

Depending on the treatment type and quality, digested or stabilized sludgecan be applied to public or private lands for landscaping or agriculture.

Sludge that has been treated (e.g., co-composted or removed from a planteddrying bed, etc.) can be used in agriculture, home gardening, forestry, sodand turf growing, landscaping, parks, golf courses, mine reclamation, as adump cover, or for erosion control.

Although sludge has lower nutrient levels than commercial fertilizers (fornitrogen, phosphorus and potassium, respectively), it can replace them fullyor in part. Additionally, treated sludge has been found to have propertiessuperior to those of fertilizers, such as bulking and water retentionproperties, and the slow, steady release of nutrients.


Solids are spread on the ground surface using conventional manurespreaders, tank trucks or specially designed vehicles. Liquid sludge (e.g.,



from anaerobic reactors) can be sprayed onto or injected into the ground.

Application rates and usage of sludge should take into account the presenceof pathogens and contaminants, and the quantity of nutrients available sothat it is used at a sustainable and agronomic rate.

Appropriateness

Although sludge is sometimes criticized for containing potentially highlevels of metals or contaminants, commercial fertilizers are alsocontaminated to varying degrees, most likely with cadmium or other heavymetals. Faecal sludge from pit latrines should not have any chemical inputsand is, therefore, not a high-risk source of heavy metal contamination.

Sludge that originates at large-scale wastewater treatment plants is morelikely to be contaminated since it receives industrial and domesticchemicals, as well as surface water run-off which may contain hydrocarbonsand metals. Depending on the source, sludge can serve as a valuable andoften much-needed source of nutrients. Application of sludge on land maybe less expensive than disposal.


The greatest barrier to the use of sludge is, generally, acceptance. However,even when sludge is not accepted by agriculture or local industries, it canstill be useful for municipal projects and can actually provide significantsavings (e.g., mine reclamation).

Depending on the source of the sludge and on the treatment method, it canbe treated to a level where it is generally safe and no longer generatessignificant odour or vector problems. Following appropriate safety andapplication regulations is important.

WHO guidelines on excreta use in agriculture (refer to «FurtherResources») should be consulted for detailed information.




Spreading equipment must be maintained to ensure continued use. Theamount and rate of sludge application should be monitored to preventoverloading and, thus, the potential for nutrient pollution.


29.10.18, 15*03How Treatment Technologies Impact the Climate: Sludge Disposal in Jordan


Sludge Generation & Disposal inJordanAround 67% of the households in Jordan are connected to 34 wastewatertreatment plants through sewer network. Others have on-site treatmentunits (septic tanks) which do not function well in many cases, causingenvironmental harm and financial burden due to the frequent need ofdesludging.

The treatment plants in Jordan use various types for sludge dryingtechnologies (centrifugal, belt press, stabilisation ponds, (unplanted) dryingbeds). The dried sludge is usually stored in the facility and then transportedfor disposal (such as Al-Akaider, Ain Ghazal, Al-Lajjoun sludge treatmentplants and landfills).

But for the liquid sludge sometimes the drivers of the trucks discharge thewaste in the wadis or illegal dumpsites which affects the environment ofthat area in a severe way and decreases the quality of soil. In addition, thatit may contaminate the ground water bodies knowing that Jordan dependsmostly on groundwater (46%) as a drinking water resource.

Sludge Reuse

Sludge that has been treated (e.g., co-composted or removed from a planteddrying bed, etc.) can be used in agriculture, home gardening, forestry, sodand turf growing, landscaping, parks, golf courses, mine reclamation, as adump cover, or for erosion control. In Jordan reusing of treated sludge isstill not accepted due to several socio-cultural and political factors.

However, in Jordan there is a good example of reusing sludge for BiogasEnergy generation in As Samra WWTP. As Samra – as the biggest WWTP inJordan – covers 80% of its energy demand by wastewater hydropower andbiogas electricity.

29.10.18, 15*03How Treatment Technologies Impact the Climate: Sludge Disposal in Jordan


Please find some details on the As Samra WWTP on the next page.


29.10.18, 15*05How Treatment Technologies Impact the Climate: As Samra WWTP


Energy production in As SamraWWTPThe ASs Samra WWTP receives 80% of its electricity needs through thecombination of hydraulic turbines and gas turbines powered by digestionbiogas. The remaining 20% electricity is used from the national electricitygrid.

The As Samra wastewater treatment plant (WWTP) was built to replace theold, overloaded As Samra Wastewater Stabilisation Ponds(WSP). Construction of the As-Samra WWTP was undertaken between2003 and August 2008.

With a peak flow of 840,000m³ each day, the facility treats an average flowof 267,000m³ of wastewater, serving a population of 2.2 million living inthe Greater Amman and Zarqa areas.

The As Samra WWTP was built to improve the quality of water in Jordan. Ittreats wastewater released from the Zerqa river basin, which is part of thetwo populated cities of Greater Amman and Zerqa. The Zerqa river drainsmost of its polluted water into the King Talal Dam, which providesirrigation water for the Jordan Valley, causing significant environmentaland health concerns.

The construction of As Samra WWTP relieved most parts of Jordan byproviding safe reuse of water for irrigation. It also eliminated the odors thatwere being released from the former WSP.

As-Samra WWTP consists of a primary settling tank, eight aeration tanks,eight secondary settling tanks, four anaerobic sludge digesters, biogas andhydro-powered generators, and an odour control system. The aerationtanks, secondary settling tanks, and anaerobic sludge digesters tanks are allpre-stressed with the DYWIDAG Strand Tendons.



Further ResourcesYou now have a rough understanding of the problems and conceptsdiscussed in this lesson. While the previous pages gave an overview, thefollowing resources are now meant to «dive deeper» and to learn more.

The resources offered here are carefully selected. The occupation which thepapers, videos, etc. raised here is therefore essential to complete this lessonsuccessfully

Video

Faecal Sludge Dewatering

EAWAG Aquatic Research: Faecal Sludge Dewatering, 2018.4:20 min

Faecal sludge dewatering is currently one of the biggest challenges foreffective faecal sludge management. This video explains what dewatering

https://www.youtube.com/watch?v=FnKubxbsE-M

https://www.youtube.com/channel/UCdDwnhvbqp2qMN1D4XyS8nA



is, why it is so difficult for faecal sludge, and shows some potentialsolutions for the future!

3.5 Use and/or Disposal - Agricultural Use as Fertilizer and Soil Condi…

EAWAG: Planning & Design of Sanitation Systems andTechnologies, 2016. 7 min

Use and/or Disposal - Agricultural Use as Fertilizer and Soil Conditioner

Documents

https://www.youtube.com/watch?v=UOReaEzCJU4

https://www.youtube.com/channel/UCgHWg270mPystIe5rVFOvCA



[click the image to open the PDF (37mb,427 pages)]

EAWAG, IWA (2017): Strande, L., Ronteltap, M. and Brdjanovic,D. (Eds.) (2014). Faecal Sludge Management. Systems Approachfor Implementation and Operation.

This book is an impressive resource that capitalises on recent scientificevidence and practical solutions tested at scale by sector professionals. Itcompiles lessons drawn from rigorous scientific and case studyinvestigations to formulate operational approaches and solutions forplanners, engineers, scientists, students, and researchers.

Detailed book compiling the current state of knowledge on all aspectsrelated to FSM.

WHO (2006). Guidelines for the Safe Use of Wastewater, Excretaand Greywater. Volume 4: Excreta and Greywater Use inAgriculture. World Health Organization, Geneva, CH.

http://www.dis-course.net/fileadmin/climate_impact/resources/L21-Faecal_Sludge_Management_Strande.pdf



[Click the image to open the PDF, 99 pages]

[click the image to open the PDF (15mb, 204ppages)]

Discussion of health risks andrecommended guidelines forapplication

USAID Jordan2014: KINGDOM-WIDEBIOSOLIDS MANAGEMENTPLAN

This Kingdom-Wide BiosolidsBeneficial Use Strategy (andthe study) is organized as follows:

Kingdom-Wide BiosolidsActivities: The sectionsummarizes keysludge/biosolids treatment anduse activities ongoing inJordan.Kingdom-Wide SludgeProduction: This sectionprovides a summary of WWTPfacilities in the country, currentsludge treatment processes, andsludge/biosolids projections.End Use Outlets: This sectiondescribes potential outlets forbiosolids. Cement kilns,incineration, and landapplication are the primarybeneficial outlets considered,with disposal at landfills alsobeing investigated.Biosolids Disposal and

http://www.dis-course.net/fileadmin/climate_impact/resources/Biosolids_Management_in_JordaN.pdf

http://www.dis-course.net/fileadmin/climate_impact/resources/WHO-Guidelines_Vol4-eng.pdf



Beneficial End Use Strategy: This section summarizes end use anddisposal opportunities, describes potential interim strategy, andproposes next steps moving forward.

29.10.18, 15*07How Treatment Technologies Impact the Climate: Sector Framework & Policies


EXCURSUS: Sector Framework& Policies

It is not allowed to:

Irrigate crops which are eaten raw with treated wastewater regardless ofits quality;

Use untreated wastewater in irrigation (strictly prohibited);

Irrigate crops that are eaten cooked unless the faecal coliforms are lessthan 100/100ml and intestinal helminthes eggs count is less than 1/liter;

Use treated wastewater for irrigation of cultivated areas (Grazing);

Use sprinklers for irrigation except for golf courses.

The Jordanian institutional framework for wastewater and faecal sludgemanagement as well as wastewater and sludge reuse provides opportunitiesand however also challenges for the sector with regards to technicalsanitation solutions. In terms of sector governance, several ministriesand institutions share the responsibilities for sanitation and waterservices:

The Ministry of Water and Irrigation (MWI) has overallresponsibility for policies and strategies in the water sector, includingwater and wastewater supply and related projects, planning andmanagement. The Water Authority of Jordan (WAJ), the Jordan ValleyAuthority (JVA) and four public utilities (public water companymanaged according to commercial principles) are responsible of waterand wastewater service provision, incl. constructing, managing andoperating wastewater treatment.



Surveillance is currently performed by service provider (WAJ) and alsodirectly by an independent regulator (Ministry of Health). The Project Management Unit (PMU), being part of WAJ,regulates water supply and wastewater utilities, promotes privatesector participation in the water sector and carries out tasks related toproject planning and executionThe Ministry of Agriculture (MoA) is strongly tied to water policyand empowered through the Agriculture Law (2002) to monitor soiland crops and provide Extension service in areas where treatedwastewater is used. The Ministry of Environment (MoE) is responsible formonitoring groundwater quality, treated wastewater quality, as well assoils in areas that are irrigated with treated wastewater.

Private Sector Participation

Several small-scale Private Sector Participation (PSP) options havebeen implemented for improvement of Non-Revenue Water ingovernorates all over Jordan.Build, Operate and Transfer (BOT) contracts for two projects (As-Samra wastewater treatment plant, Disi Water Conveyance).Private water supply and desludging services (owned by individualsand companies), some are licensed, other informal.

Successful treatment and reuse of sanitation products relies on appropriatepolicies, legislations, institutional frameworks and regulations. In face of itsextreme aridity, scarcity of water resources and high population growth,Jordan has developed over the past decades a strong policy towards treatedwastewater and reuse in agriculture as a strategic component and tool forintegrated water resource management. While water supply is prioritized bythe government, a shift towards sanitation is observed within the pastdecade.

The government was able to establish an acceptable institutional and legal



framework by adopting different policies on sanitation, water pricing,standards and health protection. Moreover, the countries official waterstrategy, the Jordanian standards of treated wastewater and establishmentof committees for the coordination of wastewater reuse helped putting thetopic on the top of the political agenda.

29.10.18, 15*08How Treatment Technologies Impact the Climate: Legal Framework in Jordan


The Legal Framework in JordanTreated Wastewater

Although centralized sewerage networks and treatment systems dominatethe sanitation sector, the Jordanian government defined the utilization ofdecentralized wastewater treatment and reuse (DWWT&R) systems forrural communities and per-urban areas as one of the goals in the WaterStrategy 2016-2025.

Moreover, the Jordan Policy on DWWT (2016) is the first of its kind in theArab world, introduced to meet the growing demand for wastewatercollection and reuse to protect the limited fresh water resources. In order tosupport the introduction of decentralized / smaller systems as a possibletechnology option, MoWI has established an inter-ministerial NationalImplementation Committee for Effective Integrated WastewaterManagement (NICE) in 2013.

This committee developed regulatory and administrative tools (framework),such as technology and reuse standards, site development procedures,operation & maintenance schemes, selection of upscale implementationareas, etc. The relevant policies are summarized in the following table:



[Key policies for wastewater and faecal sludge management and reuse]

Besides comprehensive policies, severe institutional bottlenecks exist whichpartly hinder the successful implementation of concepts forcentralized and decentralized wastewater and faecal sludge management:

The recovery of capital and operational costs for sanitationservices has been a long-battle for the Government of Jordan, not beingable to collect enough revenues from users. Consequently, the coverage ofthe related expenses and financing of the sector depends heavily ongovernment subsidies and on international grants and loans. The MWIcharges similar prices for both fresh and treated wastewater used forirrigation based on block tariffs. The current policies focus on theaffordability for its users, but does not offer incentives for farmers to usetreated wastewater over fresh water.

Despite recognizing the advantage of decentralized sanitation solutions forcertain areas, effective decentralized services are hardly supported orencouraged. Reasons include:

The lack of participatory measures and required community

http://www.dis-course.net/uploads/pics/table-legal_policy.jpg



involvement, resulting in low levels of trust between local communitiesand national government and/or international decision makersSocio-cultural barriers hinder the acceptance of decentralized solutionswithin communities and local governorates Lack of clear procedures and responsibilities among WAJ, utilities,municipalities, potentially private companies and other ministries foroperation, financing and monitoring of decentralized services and non-conventional sanitationNon-existence of regulations for non-conventional sanitation toadjusted and differentiate the requirements of the sector as comparedto centralized sanitation servicesAddressing the lack of capacities and incentives needed for properplanning and management of wastewater generated by smallcommunities Responsibilities for permission, EIA approval, monitoring ofdecentralised wastewater management projects currently lie withnational authorities, while authorities and entities at governorate levelhave weak capacitiesThe NICE Committee has still limited influence on binding regulationsand is slowed down in its process by the conflicting views of itsmembers (ministerial stakeholders)

Sludge Management

On an operational level, stakeholders play a major role in the FeacalSludge service chain. It is a mixture between governmental, non-governmental and private sector. In addition to involve the broader societywhen it comes to the crucial issue of social acceptance is important.

The involved stakeholders in the topic of sludge reuse differ according totheir direct relation to the service chain, strength and weaknesses of each.Nevertheless, the a crucial point is the coordination between all theseplayers. In most regions, municipality/public utilities are responsible forthe provision of sanitation services. Private companies in coordination with



the municipalities play a main operation role of emptying, transporting,treating and disposal/reuse of the FS, in other words manage the FS safely.Private companies are sometimes contracted by municipalities/publicutilities for desludging activities. Also, private companies operateindependently in regions where public entities are unable to provide reliabletimely services.

[General stakeholders and their roles regarding the sanitation service chain]

Like many other countries, Jordan has long neglected the need andopportunities of faecal sludge management and highly prioritized themanagement and reuse of wastewater.

As of today, all treatment plant in Jordan are challenged with the finaltreatment and safe disposal of sludge resulting in the fact that effectivefaecal sludge management has now become a priority for WAJ and MoWI.

Nonetheless, a strong policy, regulatory and financing framework fortreatment and stabilization alternatives as well as disposal options that canoverlap with treatment options does not yet exist, but is severely needed.Considering the amount of sewage sludge that is irregularly collected orillegally disposed, a significant mind-shift among decision-makers as well asthe general public is required. Within this context, particular focus shouldbe put on creating opportunities for resource recovery and reuse, such as re-

http://www.dis-course.net/uploads/pics/table21.jpg



use of biosolids in agriculture and co-incineration.

The large number of actors within the sector and along the sanitation valuechain display a lack of coordination of their activities and have overlappingresponsibilities, thus causing a reduction of effectiveness and efficiency.

Disposal of untreated sludge into the environment poses a major threat forhealth and environment. The relevant laws are in place, but theirenforcement is not adequate and weak.

29.10.18, 15*08How Treatment Technologies Impact the Climate: National Guidelines, Standards & Norms


National Guidelines, Standards& NormsWastewater Management

A well-established regulatory system is in place when it comes towastewater management (incl. collection, treatment and discharge / finaldisposal). Standards are defined, policies are in place, mandates arerelatively clear, and a monitoring and control system is well establishedwhen it comes to, for example, effluent quality. However, as mentionedabove, this positive development applies mainly to centralizedsystems.

The wastewater and sludge regulation and reuse standards (in agriculture)are fundamental, however, the major challenge continues to be theimplementation and enforcement of these regulations and standards due toseveral socio-cultural and political factors. The relevant Jordanianstandards are summarized in following table:

[National guidelines, standards and norms according to its thematic focus

http://www.dis-course.net/uploads/pics/table_guidelines.jpg



and responsible authority]

Key regulatory parameters and aspects include:

Reclaimed water must comply with the conditions stated in JS 893/2006,published by Jordan’s Department for Standards for each of its planned enduses, such as:

Irrigation of vegetables that are normally cooked, Tree crops, forestry and industrial processes, Discharges to receiving water such as wadis and catchments areas, Use in artificial recharge to aquifers not used for drinking purposes, Discharge to public parks or recreational areas, Use in irrigation of animal fodder,Use of reclaimed water for cut flowers.

The use of reclaimed water for other purposes, such as e.g. cooling,underlies additional standards and guidelines. The irrigation of vegetablesand fruits that are eaten uncooked like lettuce, tomatoes and onions isprohibited. While monitoring programs are in place to ensure thecompliance with the regulations in terms, there is still a lack ofimplementation of standards, which is due to numerous factors, incl. lowerquality of effluents from overloaded treatment plants, lack of knowledgeamong farmers, lack of alternative water sources, etc.



[JS 893/2006 mentions the following specifications and standards. Thestandard differentiates between different reuse purposes (Class A, B, C andCut Flower)]

Sewage Sludge Management

The main legislation relevant to sludge production is the WaterAuthority Law (No. 18, 1988), which states that WAJ assumes allresponsibilities and authorities related to water and wastewater, includingthe management of WWTPs and hence any product of WWTPs. However,the law does not include any explicit provisions regulating the means ofsludge disposal and/or the production of biosolids for disposal or reuse.

Instead, a Technical Regulation (JS 1145/2006) on the Uses ofTreated Sludge and Sludge Disposal exists to regulate the entire cycle ofsludge production to its reuse as a soil fertilizer (for fodder and fruit tree

http://www.dis-course.net/uploads/pics/table-limits.jpg



farming) or soil conditioner (for rangeland restoration) or its disposal inlandfills. JS 1145/2006 specifies thresholds for parameters that determinethe quality of treated sludge (biosolids). It would be classified into threeclasses:

class (1) being that of the highest quality suitable for fodder and fruittree farming as well as rangeland restoration (where annual rainfalldoes not exceed 200 mm and no irrigation takes place), class (2) being suitable only for rangeland restoration class (3) not suitable for neither and to be landfilled.

[Maximum allowable concentration levels for the 3 different classifications]

Further details exist on methods and quantities for land application.However, despite the presence of a legislative framework to regulate theland application of biosolids, instructions were issued by the Ministry ofAgriculture and the Ministry of Environment banning the production anduse of organic fertilizers from materials originating from WWTPs (MoA,

http://www.dis-course.net/uploads/pics/table21-1.jpg



2009).

Both authorities have overlapping responsibilities when it comes toregulating biosolid reuse (MoA, 2005 and MoE, 2006). Nevertheless, MoAopens up for occasional opportunities of academic experiments for biosolidreuse.

[Thematic Focus of Standards]

In general, the sludge regulation and reuse standards (inagriculture) are fundamental. However, the major challenge continuesto be the implementation and enforcement of these regulations andstandards due to several socio-cultural (acceptance) and political factors. Inaddition, the fact that two authorities – MWI and MoA – have overlappingresponsibilities when it comes to regulating biosolid reuse, causes majorproblems to regulate a safe reuse of treated sludge and bring the topicforward.

Compared to wastewater, FSM as well as reuse of biosolids is presently apart of the sanitation sector that lacks comprehensive regulation,definition and applications of standards and clear mandates by responsibleauthorities.

As a conclusion, end use outlets for sludge or biosolids currently cannot beimplemented due to regulatory impediments and a need to gain stakeholderbuy-in on practices that are regionally and internationally accepted.

However given both – the agronomic and energy value of sludge – marketdemand should develop over time in both agriculture and as an alternate

http://www.dis-course.net/uploads/pics/national_standards_01.jpg



energy source. Recognition for the need to revise regulations associatedwith land application to permit reuse for fodder crops and rangelandsrestoration exists within the Jordanian professional community and withingovernment organization.

Similarly, as energy prices continue to rise, sludge as an alternate energysource will become more viable. Furthermore, the increasing lack in fertilityof the soil and hence agricultural efficiency on a national scale, will triggerthe need of sludge as a valuable resource for soil improvement.

29.10.18, 15*13How Treatment Technologies Impact the Climate: Questions?


Self-Test Module 7This page gives the opportunity to check yourself whether all of contentoffered in this module has been understood correctly. Perhaps you shouldre-read some pages? The decision about this and the identification ofcontent which has not been digested correctly is totally up to you!

Your answers in the «Self-test» section are not controlled. However, if youare able to give correct answers in these self-tests, you are also wellprepared for the obligatory online test at the end of the whole e-Learningcourse!

Following are some multiple choice (several answers per questions may becorrect in this case!) or «free text» questions. Please click on «± Proposedanswers» to learn if you can give a correct answer!

Question 1.: Sludge treatment methods are...

[ ] Aerobic digestion

[ ] Sedimentation

[ ] Mechanical dewatering

[ ] Air drying and composting

Question 2.: What are the advantages of sludge disposal andstorage?

[ ] No odors noticeable

[ ] Low capital and operating costs

[ ] Storage can make the produce more hygienic



[ ] Little operation skills necessary

Question 3.: What are disadvantages of the application of sludge?

[ ] Health risks if not applied correctly

[ ] Possibility of contamination of groundwater

[ ] Social acceptance may be poor

[ ] Possible reduction of erosion

Question 4.: Wastewater treatment plant effluent can be reusedfor...

[ ] Irrigation

[ ] Groundwater recharge

[ ] Surface water recharge (e.g. for swimming pools)

Question 5.: Soak pits can be used...

[ ] For primary treatment of wastewater

[ ] In densely populated urban areas

[ ] To recharging clean groundwater without contaminating it

[ ] For letting pre-treated water slowly soak into the ground

Question 6.: Leach fields require...

[ ] Expert design and construction

[ ] Primary treatment to prevent clogging



[ ] Very high maintenance, even without mechanical equipment

[ ] A large land area

Question 7.: What are appropriate irrigation technologies fortreated wastewater?

[ ] Spray irrigation

[ ] Drip irrigation

[ ] Surface water irrigation