Graywater Reuse in Jordan
Prepared by Stephen McIllwaine, 2003
Download PDF format of the Arabic version of this report
(file size is 1.28 MB)
This report is part of the CSBE Graywater Reuse project, a project funded by the Enhanced Productivity Program at the Jordanian Ministry of Planning.
Table of Contents for the Report:
- Low-Cost Village Reuse
- Care - INWRDAM Graywater Kit Distribution Project
- King Abdullah Mosque
- HB House - Amman
- Test Scheme at JUST
- Urban Household Laundry Water
- MA - Private Garden Sink
- RSCN Nature Center
- BF House - Amman
- Ghuwaybah Mosque
- CSBE Demonstration Unit
- Adasiyyah Demonstration Application
- Al-Himmeh Demonstration Application
- Adasiyyah Girls' School
- The Current Position
- Separate Regulations of Large and Small Usage Applications
- Management of Risk
- Following the Arizona Legislation
- Long Term Project Performance
- Type of Use
- Concerns over Changes to Wastewater Quality
- Promotion & Education
In September 2002, CSBE received a grant from the Jordanian Ministry of Planning to investigate the use of graywater reuse in a domestic context, and determine its suitability in Jordan. The project consisted of 3 components;
- Investigation of existing graywater practices and experiences in other countries, including technical, social and economic factors that may have a bearing on the implementation of graywater reuse schemes in Jordan.
- Interaction with a number of graywater schemes that are being designed or implemented in Jordan, and provision of technical assistance to them where appropriate.
- Provision and distribution of useful information on graywater reuse, based on experience gathered during the project.
A report on graywater practice and experience in other countries was completed in January 2003 - ‘Graywater Reuse in Other Countries and its Applicability to Jordan'. This contains useful background information on graywater systems developed in other countries, issues relating to plant and human health, and graywater legislation in force in different countries. This report is now available on the CSBE website in English and Arabic.
Following the completion of that report, CSBE began to visit a number of existing and potential graywater applications and users. Advice and assistance was provided to a number of people who wished to investigate reusing their graywater. As a result, a number of graywater schemes have now been developed, at both design and implementation stages, with assistance from CSBE. A number of schemes are up and running and others are under design or consideration. All are being implemented and funded by the private householders or institutions themselves. From these, CSBE has begun to gather useful information on the issues relating to the reuse of graywater in Jordan, although a more prolonged period of monitoring and assessment will be required fully to determine the suitability and applicability of such systems.
To assist those who wish to explore graywater reuse themselves, a set of guidelines on graywater reuse has been produced and is available on the CSBE website in English and Arabic, and a brochure containing simple advice on graywater reuse has also been developed and printed.
In addition, a workshop for professionals interested in the subject was held in Amman, in September 2003, providing a forum for sharing of ideas and experiences in the Jordanian context.
This report contains information on graywater reuse in Jordan and contains details of schemes that CSBE has assisted as well as schemes developed by others. The report is a snapshot of the various projects as at August 2003. There is a growing interest in graywater reuse in Jordan and this report provides a basic framework of advice and context that will be useful to those interested in developing their own schemes for graywater reuse.
It is clear that many of the schemes presented here are at an early stage of development. Further monitoring and assessment will be required in order fully to evaluate them. CSBE will continue to assess and monitor these schemes, using funding from the British Embassy in Amman Small Grants Scheme, and will produce a further project report in 2004.
2.0 Existing Graywater Reuse Applications in Jordan
During the course of this investigation, it became apparent that a number of households and organizations in Jordan were already successfully reusing graywater, with various degrees of success. Some of these were recorded in the previous report ‘Graywater Reuse in Other Countries and its Applicability to Jordan', while others have been discovered subsequently.
2.1 Low - Cost Village Reuse
Many examples of simple graywater reuse in village households in rural Jordan have been discovered. Water from the kitchen sink and sometimes other washbasins is applied directly to soil in the garden. There is often little or no filtering, and no other treatment of the graywater. These examples of simple, low cost, user-driven graywater reuse indicate both the need for additional water sources, and the ease with which simple applications can be developed and maintained. Figure 1 illustrates a simple case of graywater reuse with little or no treatment.
The advantages of such systems include their low-cost (often little more than an additional piece of pipe work), and their ease of use. Little or no maintenance is required, and the user is in full control over the system at all times. An additional advantage (often the prime incentive in low-income contexts) is the reduction in demand for septic tank pump-out, which represents a tangible cost saving to the householder over the year.
These simple systems do have some disadvantages. Since there is no treatment or fail safe system, it is important that the householder will take care not to dispose of substances harmful to plants (such as bleaches and other strong cleaning agents) into the graywater system. With no filtration (other than perhaps the coarse screen at the sink drain), much organic material (particularly from the kitchen sink) enters the system, and a number of such reuse sites were found to contain elements of organic food waste in the irrigated area. There is a potential health risk from these, although since the bacteria quickly die in healthy soil, and the household waste is generally used within the property, the risk is small.
Overall, it appears that in some areas of Jordan, where water is particularly scarce, forward thinking people have developed simple ways of making their water go farther, by reusing a component of their domestic graywater. Solutions are low cost, involving no complex technology or materials. Risks to plants are managed by controlling inputs to the graywater, and risks to human health, already small, are minimized by common sense care over how the water is used. This is water demand reduction by necessity, and backs up the argument for encouraging graywater reuse on a wider scale in Jordan. It works, it is easy to use, and, for some at least, it is worth the effort.
2.2 Care - INWRDAM Graywater Kit Distribution Project
For over a decade, Care International, in conjunction with the Inter-Islamic Network on Water Resources Development and Management (INWRDAM) has been distributing and installing graywater units to villages in rural Jordan. These units consist of piping to capture graywater from the dwelling, plastic barrels for graywater treatment, an automatic pump to take the graywater to the irrigation system, and irrigation piping and valves.
Some units contain 2 treatment tanks (barrels) and include grease separation and filtration. Other units contain 4 tanks and include an anaerobic digestion process.
Figure 2 is a schematic of the basic 2 and 4 barrel systems, and Figure 3 shows an installation of this system in the village of Buseira in the Tafileh Governorate in the south of Jordan. The sunken barrels and the pump can be clearly seen. Over 600 4 barrel units have been installed recently in villages around Jordan with funding from the Ministry of Planning, Enhanced Productivity Program.
In the 2 barrel system, graywater is captured at an appropriate outlet at the side of the dwelling and drains by gravity into the first barrel where it is allowed to settle. Settlement of solids and separation of grease occurs here. The cleaner water then passes to the second barrel through a fabric mesh filter, from where it is pumped into the irrigation distribution network. The barrels are sealed, eliminating the release of odors. A float sensor activates pumping of the graywater once the graywater level reaches a certain level. In the 4 barrel system, the two additional barrels contain gravel medium through which the graywater passes in an upwards direction. Anaerobic digestion occurs in these barrels, to produce a higher quality effluent.
The benefit of the 2 barrel system lies in its ability to remove greases and solids from the graywater, including organic material. Grease and solids removed from the graywater are contained within the barrel system and are removed manually during periodic maintenance. The 4 barrel system allows for anaerobic treatment, although the need for this is questionable, given that the resulting water will be used for irrigation of plants growing in soil. No results are yet available as to the efficiency of this treatment stage.
The 2 barrel units visited by CSBE in the Buseira area had been on-line for only 1 or 2 months, but there was a high degree of early customer satisfaction. Many of the households where this system was installed had been already reusing graywater, although without the degree of treatment this system provides. Early feedback from the 4 barrel installations indicates a problem with odor emission from the anaerobic stage due to faulty operation of the non-return valve. This is being investigated by INWRDAM. For more detailed information on this extensive project, INWRDAM may be contacted directly at email@example.com (Tel: Amman 5332993).
The main potential drawbacks of these systems arise from their complexity and cost. Although many of the components (plastic barrel, plastic piping) are available and inexpensive, the pump and float sensor will increase the cost of the system. Pumping graywater, even after filtering, through a pump will give rise to a pump maintenance requirement, through time. Additionally, the power requirement of the pump (even though it may only be required for a few minutes each day) will increase the ongoing costs of this system. Also, if the barrels are not properly sealed, odors will result, in addition to the odor problems with the 4 barrel system due to the valves. The treatment provided in these systems will not remove chemical contaminants, and a degree of care is therefore assumed on the part of the householders, although the anaerobic component of the 4 barrel system will reduce the biological strength of the graywater. Through time, as the effective maintenance and running costs of these systems are recorded, a fuller assessment of their suitability for a low-income village environment may be made.
2.3 King Abdullah Mosque
As was noted in the previous report, ‘Graywater Reuse in Other Countries and its Applicability to Jordan', wastewater from the ablutions of worshippers at the King Abdullah Mosque in Amman is collected, pumped to a rooftop storage system where it is filtered, and reused to irrigate areas of ornamental plants in the grounds of the mosque. The system has been installed for around 5 years, and has resulted in significant savings on the mosque's water bills. The capital costs for the installation of the system were recouped within the first year of operation.
Water quality testing on the water before and after filtering was carried out by CSBE in May 2003 and the results are presented below.
|Parameter||Concentration before filtration||Concentration after filtration||JS 893 / 1995 for irrigation of cooked vegetables||JS 893 / 1995 for irrigation of fruit trees|
|Chloride, Cl (mg/l)||0.12||0.18||350||350|
|Sodium, Na (mg/l)||52.1||49.0||230||230|
|Faecal Coliforms (MPN/100 ml)||700||2||1000||-|
Table 1: Results of water quality tests conducted on the graywater collected from the place of ablution at King Abdullah Mosque
EC: electrical conductivity - a measure of water salinity.
pH: a measure of acidity or alkalinity (less than 7 is acidic, greater than 7 is alkaline).SAR: sodium adsorption ratio in the water.
Faecal Coliforms: a measure of the degree of bacterial contamination from humans and animals.
BOD: biochemical oxygen demand - a measure of the amount of organic matter. It specifically measures the demand for dissolved oxygen from microorganisms as they attempt to break down organic material.
As expected, these results show very low levels of contaminants in the graywater to begin with. The guidelines given in Jordanian Standard 893/1995 for irrigation of cooked vegetables and fruit trees by treated wastewater have also been included in the table for comparison. It is clear that this type of graywater is suitable for the irrigation of cooked vegetables and fruit trees, or of ornamental plants in the grounds of the mosque even before filtering. It is interesting to note that the main effect of filtering on the parameters in question is to reduce the BOD load and the faecal coliform count, mainly through the removal of organic material form the water. However, even the unfiltered graywater would be suitable for use in irrigation of ornamental plants.
2.4 HB House - Amman
A second example of urban graywater reuse which was recorded in the Phase 1 report is where a householder in Amman has installed a simple graywater system where graywater from one bathroom in the house is intercepted at an external manhole and is taken to a horizontal underground pipe supplying the water to a row of plants. There is no pumping or filtering of any kind. No change of behavior was necessary on the part of the householders, since all the water from the bath, shower, and bathroom sink is applied directly and automatically onto the plants. This system has been operating for over 2 years and there are no signs of stress on the plants or the soil. The cost of the manhole divert and the piping are reckoned to be of the order of 20 JD (around 28 USD), and there is little or no ongoing maintenance required.
Soil quality tests were carried out at this site by CSBE in order to determine if there has been a buildup of indicator contaminants over this period of time. Samples were taken in June 2003 (following the end of the winter rains) and again in October 2003, after a period of summer drought, but before the first rains of the autumn period. The soil tested was gathered from the entire area to which the graywater has been applied, and could be considered representative of the general characteristics of the soil over a wide area, and not just as a spot sample taken in one place. The results are presented below;
|Parameter||Soil which has been irrigated by GW Jun. 2003||Soil which has been irrigated by GW Oct. 2003||Soil which has not been irrigated by GW Oct. 2003||Guidelines from Agricultural Handbook No. 60|
|Soil Classification||clay soil||clay soil||clay soil|
|EC (dS/m)||0.79||1.48||0.78||TDS <4000|
|Chloride, Cl (mg/l)||1.88||7.10||3.45||<106|
|Sodium, Na (mg/l)||26.9||31.7||7.00||<115|
|Faecal Coliforms (MPN/100 ml)||240||2||0||<1000|
Table 2: Results of soil quality tests conducted on the soil at HB House - Amman
These results are interesting and indicate two important trends. Firstly, by comparing the graywater-positive results from June and October, it is apparent that the winter rains have a significant flushing effect on the soil. There is a rise in concentration of all the major parameters (with the exception of faecal coliforms). The rise in salinity (from 0.79 to 1.48 dS/m), in chloride (from 1.88 to 7.10 mg/l), sodium (from 26.9 to 31.7 mg/l), in SAR (from 0.65 to 1.86) and in boron (from 0.33 to 0.44 mg/l), all reveal a buildup in these parameters during the summer months. Although more comprehensive testing over a number of summer-winter cycles would be advisable in order to provide a more long term pattern, it is likely that the buildup in the concentration of these substances is due to the application of graywater. During these months, the soil in question has been irrigated by graywater in the absence of rainfall. All the substances listed above, whose concentrations increased, are constituents of soap and detergent products used in showers and bathrooms, and would be expected to be present in the graywater (although no specific tests on this bathroom graywater were conducted). It is likely that a proportion of the substances in graywater are remaining in the soil, following irrigation. The significant rainfall during the winter months would have the effect of flushing out much of the increased concentration of such substances, and effectively cleansing the soil. This may well prove to be a significant factor in reducing the detrimental effect of graywater irrigation in Jordan.
The second point to note is also important. The soil at this site has been irrigated by graywater for a number of years - a number of summer/winter cycles. It is interesting to note that at the end of the winter rains, the concentrations of these key parameters in the soil irrigated by graywater, are generally not excessively above that in the adjacent sample of soil which has not been irrigated by graywater. In addition, they are substantially below the maximum levels set out in the Agricultural Handbook. This demonstrates that in this case, there has been no long term buildup of contaminants in the soil, as a result of irrigation by graywater. As discussed above, this may be due to the annual flushing of the soil by the winter rains (around 500 mm/year on average, at the site in question).
The lower concentration of faecal coliforms in the soil in October 2003 is unexplained, but may be a result of the significantly drier soils conditions at the site, which would disfavour the growth of such coliforms.
2.5 Test Scheme at JUST
The Jordan University of Science and Technology (JUST) has been engaged in a project to use the graywater from one of the accommodation blocks housing 69 female students. It is estimated that 80% of the wastewater from the accommodation block - amounting to an average of about 2 cubic meters per day - is graywater. This includes the kitchen sinks. The graywater is collected at an external manhole and taken to 2 underground storage tanks from where it is pumped to the irrigation area. Figure 4 shows the irrigated planted area with the accommodation block in the background.
This work has been written up in Qaqish, LM, ‘Effect of Grey Water Irrigation on Soils and Crops', MSc Thesis, Jordan University of Science and Technology, May 2003. One interesting feature of this project was the inclusion of a reed-bed treatment system to treat a component of the graywater. A sloped enclosure was established, consisting of an area of healthy soil placed over an impermeable fabric. Reeds were cultivated in this enclosed area of soil. Untreated graywater was released into the upstream end of this zone and was captured downstream. The estimated retention time for the graywater was 4 days. The ‘treated' graywater was stored in a third tank for later reuse.
A compartmentalized irrigation area was developed, containing fava beans, spinach and carrots in controlled areas. A component of the area was irrigated with the untreated graywater. A second area was irrigated with the treated graywater, while a third was irrigated with mains water. The scheme was irrigated over a period of 5 months and tests were completed on the water, soil and the plants irrigated.
Water, soil and plant matter were extensively tested throughout the project for a number of parameters, and the results are presented and discussed extensively. The main conclusions are that the reed bed was successful in reducing the amount of BOD, COD, turbidity, nitrates and bacterial content. The results indicated a high concentration of heavy metals in the soil although this is considered to be due to impurities in the storage and distribution system, and not arising from the graywater itself. However, if the graywater were to be reused for the irrigation of ornamental plants, the presence of heavy metals in the graywater would give no cause for concern.
2.6 Urban Household Laundry Water
Wastewater from the laundry is one source of graywater which is anecdotally regarded as potentially suitable for reuse in Jordan. In order to provide more information about the constituents of laundry water in Jordan, tests were carried out on an urban household in Amman. The wastewater from one complete laundry cycle from an automatic washing machine on wash day was sampled and tested. Unfortunately, the tests were not able to be carried out directly after the wash had been completed, and the wash water was stored for 18 hours before the first analysis was carried out. The second results were taken from the stored laundry water sample, after 4 weeks of storage in a sealed barrel, standing outside the house. The results are as follows;
|Parameter||After 18 hours||After 4 weeks||JS 893 (irrigation of fruit trees)|
|EC (dS/m)||1.38||1.49||TDS <2000|
|pH||7.4||7.5||6.0 - 9.0|
|Chloride, Cl (mg/l)||213||231||<350|
|Sodium, Na (mg/l)||268||89||<230|
|Faecal Coliforms (MPN/100 ml)||16 X 10^6||16 X 10^5||-|
Table 3: Results of water quality tests conducted on the laundry water of an urban house
An expected reduction in organic content (as indicated by the BOD) is seen, with the BOD decreasing by about 50 % during the 4 weeks time period between tests. This arises from the breakdown of the organic material by the indigenous bacteria in the graywater. The coliform levels are high, indicating favourable conditions for their growth, (although the bacterial levels directly following the laundry cycle would have been much lower, following the oxidation effects of the detergent and the hot water). The bacterial levels fell by a factor of 10 during the time period, possibly indicating a reduction in the intensity of the anoxic digestion process. As expected, the results show little change for the ionic concentrations (boron and chloride), although the increase in ionic sodium content is unexplained.
The relevant guideline parameters for irrigation of fruit and forestry trees, given in Jordanian Standard 893 (for irrigation by treated wastewater) have also been presented. It is interesting to note that there is no requirement for coliform levels to be below certain limits. Provided there is no contact between people and graywater, and the graywater is not used to irrigate areas used by humans or animals (eg grass areas), the presence of coliforms in the graywater does not constitute a problem to the plants. Bacteria die quickly after coming into contact with healthy soil. All other parameters are within the range recommended by the code, with the exception of Boron and Sodium. These substances are important constituents of laundry detergent and are present in the laundry graywater. It can be seen here that despite the inclusion of the laundry rinse cycle in the test water (and the subsequent dilution effect), the concentration of these substances exceeds the recommendation in the code. Boron and Sodium are both substances which will cause damage to plants once their concentration rises above certain levels. If this laundry water were to be used consistently in graywater applications, it would need to be used in conjunction with other graywater, which had a diluting effect on these substances. In addition, care in plant selection would also be required, as some plants are more tolerant of sodium and boron than others. Further information is given elsewhere on the CSBE Graywater website.
Further research is needed to determine both the average content of laundry water in urban and rural contexts, and to determine the long term effect of high concentrations of boron and sodium on certain plants.
3.0 Graywater Applications Assisted by CSBE
A number of small simple schemes to reuse graywater have been assisted by CSBE during the course of this project. Some were instigated by CSBE, who carried out the design work, while others were already under development with CSBE providing advice and design assistance. The schemes vary in complexity and some have reached implementation stage. Others are still at design stage, and will continue to receive advice and guidance from CSBE following the completion of this component of the project.
3.1 MA - Private Garden Sink
Figure 5 illustrates this simple application of graywater reuse which serves to demonstrate the simplicity of basic graywater reuse. An external sink has been established in the garden of domestic house to assist with the maintenance of the grounds. Rather than being connected to the municipal sewer, the sink drain has been connected to a row of Firethorn shrubs (Pyracantha coccinea) through a drip irrigation line placed above the soil. Graywater draining from this sink automatically goes to irrigate the garden. Should there be a need to dispose of substances which may cause harm to plants (such as strong cleaning chemicals or paints), the drain can be easily diverted - manually - to a receptacle, thus preventing harmful substances from entering the irrigation network - see Figure 6. The contents of the receptacle may then be disposed of appropriately.
This system is so simple that it is in danger of being criticized as rather obvious, hardly worth the designation of ‘system' at all. However, this is graywater reuse at its best. It illustrates the principle underlying graywater reuse in the first place - that the reason why graywater is chosen to be used after minimal treatment is its lack of contamination. This system provides no treatment whatsoever, and none is needed, given that graywater containing contaminants will be diverted away from the plants. No consumer contact with the graywater is required to connect the diversion, provided it is done in advance. However, the system does assume a degree of care and intervention on the part of the user - both regarding what is disposed of in the sink, and in the prompt and careful use of the diversion - and is clearly designed on the assumption of high quality water. The cost of the system was no more than 10 JD (around 14 USD) - the cost of the additional hose required to connect the sink to the irrigation system. This system was installed in the spring of 2003.
3.2 RSCN Nature Center
The Royal Society for the Conservation of Nature (RSCN) has included a graywater reuse unit in its new Nature Center in Jabal Amman. CSBE assisted with the design of this unit, illustrated in Figures 7 (photograph) and 8 (sketch).
Graywater will come from the hand basins and kitchens of the Nature Center as well as from the bathrooms and laundry of 4 apartments which will be housed above the Center. The actual quantities of graywater will depend on the usage of the center and occupancy of the apartments. The unit consists of 3 chambers as shown. Graywater drains (via the vertical PVC pipe on the left of the photograph) to a mesh screen filter, easily removable for cleaning, which will remove coarser solid material such as hair, lint and food scraps. Graywater will then pass upwards through a graded sand-gravel filter, visible in the right hand window on the photograph. This variable medium will allow for further filtering of finer solids, and will provide a surface for the anaerobic breakdown of organic material trapped in the filter. The filtered graywater will appear above the medium layer and overflow into the third chamber, from where it will drain by gravity to the irrigation network. The design of the unit provides for backwashing of the filter by reverse-connecting a hose to the unit, and also contains a diversion valve which can take all graywater to the municipal sewer if necessary.
There are a number of issues of interest with this system. Firstly, the system does not serve a single family household. The Nature Center itself will be a non-residential establishment, with little volume of graywater output other than restroom sinks and possible a small kitchen area. It is not thought that meals will be prepared here. However, the building will contain 4 apartments for short term usage by guests of the RSCN and visitors. A degree of care and cooperation will need to be shown by the users of these apartments to avoid the release of strong cleaning materials and bleach etc into the graywater.
Secondly, the performance of the graywater unit itself needs to be monitored and assessed over time. The amount of solid material intercepted by the filters will be an indicator of the quality of the graywater being produced. Also, the hydraulic operation of the sand filter should be monitored to determine if it is liable to clog.
A third important issue involves the plants to be irrigated by the graywater. The irrigated area is sheltered by the Center building and as such will receive no rainfall which would have had the effect of diluting the graywater and helping to reduce the buildup of contaminants released into the soil from the graywater. In addition, the architect has elected to sow the site using spores and seeds of plants native to that particular urban area of the city. Young plants are particularly sensitive to some of the impurities in graywater, and RSCN may need to supplement the irrigation with mains water for an initial period. However, the type of plants which have survived in such a polluted urban environment will tend to be more drought tolerant and resilient to graywater.
It is clear that this unit has a degree of complexity not seen in the rural installations, and will require a higher degree of observation and user intervention. CSBE will continue to work with RSCN to monitor the performance of this unit, which at time of writing, has yet to come operational. Further results will be published on the CSBE website in due course.
3.3 BF House - Amman
This scheme is interesting in that it involves a larger urban villa dwelling in West Amman which was plumbed for graywater from its conception. Graywater from four of the bedrooms, together with the en suite bathrooms, and the laundry will be captured and taken to a settlement tank in the basement. This will be pumped for use in the irrigation of approximately 200 square meters of garden area, situated adjacent to the house. Construction of the villa is still underway, and the graywater unit and associated mechanical and electrical works is yet to be completed. However, CSBE has worked with the architect and the mechanical and electrical consultants to develop a conceptual system for detail design and incorporation by the contractor.
The schematic unit design is illustrated in figure 9.
A guiding feature of the design is the need to provide graywater which is capable of being pumped through a head of around 6 m to the garden level. Pumps work best when the water contains few solids and dissolved impurities, so it was felt prudent to include a dual filter system - a coarse screen to remove larger solid material, and a finer filter which would remove finer solids. The filtered graywater will then be stored in a chamber from where it will be pumped presumably to a smaller storage tank at garden level, from where the irrigation will be controlled. It is likely that this pump will be operated automatically by a level sensor.
A number of issues need to be taken into consideration. Firstly, if there is significant organic material in the graywater which is not removed by filtration, this will begin to undergo anaerobic digestion in the settlement tank. Unpleasant odors may be released at this stage, and it may be desirable to have this tank carefully sealed with a vent to release gases at an appropriate height. Suggestions have been made that oxidation of the filtered graywater (by ozone or chlorine) may be necessary at times to halt the digestion process and reduce odors. Provision may be made for an ozone unit at design stage, although the occasional manual insertion of chlorine tablets into the tank may also be sufficient.
Also, a means of draining this tank and disposing of the graywater to the municipal sewer (or septic tank) by gravity has been included in the design. This is necessary in case the graywater should become contaminated (for example by the release of chemicals into the water) or in the case of pump failure. A reliable control system of level sensors and pump switches will be required in order to prevent the overflow of the tank for any reason, or the saturation of the irrigated area.
The garden area will be an artificially constructed area bounded by a retaining wall. Drainage of the area via holes in the retaining wall will be permitted. However, there is a risk of the slow buildup of contaminant material in the soil following the prolonged use of graywater. It remains to be seen if this is the case. Periodic flushing of the soil with mains water will reduce buildup of materials, although it is possible that the natural rainfall at the site (around 500 mm/year) will provide sufficient natural dilution. Either way, if the project is completed in time, CSBE will sample the soil before and during graywater irrigation, to determine the effect on the soil over the long term.
3.4 Ghuwaybah Mosque
A new mosque is under construction at Ghuwaybah in Ghor al-Safi in the southern Jordan Valley. The designers expressed interest in providing a means of using the wastewater from the ablutions of worshippers to irrigate a small number of trees and shrubs in the mosque compound. Figure 10 shows the central ablutions point, all 4 sides of which will have an ablutions basin. Ablution water is generally of high quality, containing no soap or chemicals other than human hair and skin debris, dirt and sweat, as has been seen from results pertaining to the successful reuse of water from the King Abdullah Mosque in Amman. Figure 11 is a schematic layout of the mosque showing the graywater system.
Water from the ablutions basins will be combined and taken to a manhole in the floor of the mosque, together with water from the hand basins in the restroom area. A coarse screen filter at each of the basin drains will prevent larger solid material from entering the pipes. The graywater will drain by gravity from the manhole in 2 irrigation lines which will supply water to planted areas on all 4 sides of the mosque courtyard. The pipes will be laid at a gradient and each terminated in a pit filled with loose stones, designed to encourage the distribution of the graywater around the plant root area. A valve will be placed at each outlet. The provisional planting scheme will include palms in the courtyard and Bougainvillea around the pergola.
This mosque is still under construction and installation of the graywater plumbing is still underway. It is not yet known how much graywater will be produced, and how the quantities of graywater will balance the irrigation needs. Supplementary irrigation water supplies may be provided if necessary. CSBE will monitor the operation of this project once it comes on line.
3.5 CSBE Demonstration Unit
During the course of the project, CSBE visited and assessed how villagers in the villages of Himmeh and Adasiyyah in the northern Jordan Valley reuse graywater. Some examples were presented in ‘Graywater Reuse in Other Countries and its Applicability to Jordan'. As discussed, it was found that many householders were successfully reusing untreated graywater with no measurable detrimental effect on plants or humans. However, without even a basic screen filter, solid organic material from kitchens was finding its way onto the irrigated area, and there was often a degree of human contact, which could increase the risk of contamination of the user.
CSBE therefore developed a simple low-cost demonstration unit to promote use in such low water use environments. The kit is displayed in Figure 12 and consists of a simple chamber inside which is an easily removable mesh screen filter. Graywater drains via an inlet pipe onto the screen. Solid material is retained by the mesh and the water passes through the screen and drains from the chamber by gravity via the exit pipe which should be connected to the irrigation network. The internal base level of the chamber can be raised by the addition of gravel or sand to match the invert level of the exit pipe, in order to minimize the retention of graywater in the unit and the consequent buildup of odors. The filter is easily removable for periodic cleaning. The CSBE demonstration unit is made of fiberglass, so it can easily be transported for demonstration at varied locations. However, an installed unit would be more likely to be made of concrete or block, and sunk in the ground.
The key advantages of this type of simple unit include its low cost. Although the CSBE demonstration unit was made of fiberglass, a simple chamber could easily be made from other more readily available materials in a village environment such as concrete, plastered concrete blocks or metal sheets. This system is also simple. There are no moving parts or electrical components. The filter can be constructed from ordinary fly-screen mesh, and the pipe fittings may be made from standard plumbing components. No power supply is required and there is no pump requiring maintenance, (provided the land to be irrigated lies below the graywater pipe outlet). Its simplicity is ideally suited to a rural context.
One of the key disadvantages of this approach is that a degree of householder ‘buy-in' is required. Cooperation in the care of not disposing of strong cleansing products is important. There will be an inevitable contamination component in the graywater from organic material from the kitchen, and also from laundry detergent. While the organic component will cause no undue harm to the plants, high degrees of fat, oil and grease, may clog up the system. Perhaps the biggest risk factor in terms of plant health will come from the chemicals present in the laundry detergents. Boron, sodium and salinity are key constituents which may have a long term detrimental effect on the plants and soils. Different plants have different tolerances to these substances, and time will tell as to the degree to which the plants will be affected by household graywater. However, anecdotal evidence from the households currently reusing graywater suggests that provided the graywater is only used to irrigate fairly tolerant plants, there is no discernable long term detrimental effect on plants. For example, it has been observed that banana trees are more sensitive to laundry water than olive trees.
3.6 Adasiyyah Demonstration Application
A demonstration application, based on a modified version of the CSBE demonstration unit has been implemented in the village of Adasiyyah at a property which was already known to be reusing graywater. Figure 13 shows an open basin in which graywater from the household's single sink is captured. In the past, graywater was manually transferred from this basin to a number of olive trees manually via a plastic bucket.
CSBE advised on the installation of a floor drain under the sink, allowing graywater to drain to a new manhole which was installed adjacent to the former graywater basin. This manhole is shown in Figure 14, and is fitted with a stainless steel sieve which will act as a filter.
Filtered graywater drains from this manhole by gravity into a new drip irrigation system installed at the olive trees. This modified graywater reuse system eliminates the need for contact between the user and the graywater, except for periodic cleaning of the filter. The water drains automatically to the olives. Additionally, the graywater is now filtered, reducing the amount of contaminant organic material reaching the irrigated area. The quality of the graywater itself is unaffected, the assumption being that in this case, since no adverse effects on the olive trees have been noticed as a result of previous graywater reuse, this particular householder is aware of the need to take care over the inputs to the graywater system.
A soil sample was taken from the soil irrigated by the graywater, in October 2003, following around 3 months of irrigation by graywater in summer drought conditions. The soil in this area is very dry and stony, containing little in the way of healthy organic (red soil) material. The results are presented below;
|Parameter||GW + ve Oct. 2003||Guidelines from Agricultural Handbook No. 60|
|Soil Classification||clay soil|
|EC (dS/m)||1.57||TDS <4000|
|pH||8.6||6.5 - 8.5|
|Chloride, Cl (mg/l)||3.50||<106|
|Sodium, Na (mg/l)||84.1||<115|
|Faecal Coliforms (MPN/100 ml)||>1600||<1000|
|Boron (mg/l)||1.07||1 - 2|
Table 4: Results of soil quality tests conducted on the soil at the Adasiyyah demonstration application
These results show parameter levels which are well below the guideline levels (in most cases), with the exception of the level for boron which is approaching the guideline level. These results are of limited value without either a control sample of graywater-negative soil from the same vicinity, or a sample of graywater-positive soil taken at a different time. However, they will act as the basis for future comparison and are recorded here for completeness. The levels for sodium and boron are both at the high end of what might be expected for normal soils, and may indicate a buildup following irrigation by graywater (both sodium and boron are constituents in laundry water, which is one of the a main constituents of the graywater used at this site).
The reason for the raised levels of faecal coliforms is unknown at this stage, although given the direct application of the graywater onto soil with no user intervention, they give little cause for concern at this stage. It is possible that water pooling in the base of the manhole is allowing bacterial growth in the graywater - something which could easily rectified by properly detailing the manhole. Further tests on this soil will be made in the future.
Community involvement in Adasiyyah was facilitated by an ongoing project being implemented by Habitat for Humanity, together with the Adasiyyah local voluntary society. It is hoped that this simple demonstration application will engender discussion in the village and encourage householders to develop their own local graywater solutions, based on this design. There has already been significant positive community interest in graywater, and the establishment of such a simple, low cost yet effective solution should encourage the propagation of the idea, if there is a real demand for graywater reuse. One of the other benefits of the project has been the training given to a local plumber in graywater systems and their implementation. Interestingly, one of the main perceived advantages to this village which is not served by a mains sewerage system, is the potential saving to be made from a reduction in septic tank clearance costs. The continuing involvement of CSBE and Habitat in this community will enable ongoing assessment to be made.
3.7 Al-Himmeh Demonstration Application
Figure 15 is an example of a low cost dwelling unit, provided as part of a project being implemented by the Himmeh local voluntary society, in conjunction with Habitat for Humanity.
Many of the houses in Himmeh are ideally suited to graywater reuse, having separated plumbing already installed, and having an amount of garden area, adjacent to the house, at a level below the floor level of the house. As such, the graywater can be easily captured, filtered and transferred to the irrigation system, without the need for pumping.
CSBE advised on the installation of a simple graywater reuse system at this dwelling. Figure 15 shows the pipe installed to transfer graywater form the outlet pipe to a new manhole installed in the garden. Figure 16 shows the manhole, together with stainless steel sieve filter. Graywater can be seen emerging from the inlet pipe onto the sieve. The base of the manhole is filled with gravel to raise the inlet level of the manhole to match the outlet pipe and reduce the retention of graywater in the manhole. Figure 17 shows installation of new drip irrigation hose.
The design of this simple application was based on CSBE's demonstration unit, but constructed using locally available materials by a local plumber (on the advice of CSBE). This installation will act as a second demonstration unit, in the village of Himmeh, and highlight the ease with which graywater can be used in a very low cost solution. In this case, the cost includes simply the materials for the concrete manhole, a sieve, some pipe work, and labor costs.
Tests on the soil were made in October 2003, following about 3 months of regular irrigation by graywater (from the kitchen and handbasins only). The soil in this area is loamy containing a high proportion of organic material. The test results are as follows;
|Parameter||GW + ve Oct. 2003||Guidelines from Agricultural Handbook No. 60|
|Soil Classification||clay soil|
|EC (dS/m)||1.56||TDS <4000|
|pH||8.5||6.5 - 8.5|
|Chloride, Cl (mg/l)||7.10||<106|
|Sodium, Na (mg/l)||82.9||<115|
|Faecal Coliforms (MPN/100 ml)||>1600||<1000|
|Boron (mg/l)||0.38||1 - 2|
Table 5: Results of soil quality tests conducted on the soil at the Himmeh demonstration application
Again, these results are of limited value until further samples are taken for comparison. However, it can be seen that following 3 months of irrigation by graywater, all parametric concentrations (with the exception of faecal coliforms) are well below the guideline levels. The boron levels, when compared with those for the site in Adasiyyeh are significantly lower, possibly due to the absence of laundry water in the graywater (a fact that does not account for the possibly elevated levels of sodium ions).
The reason for the faecal coliform levels is unknown, but given the direct application of the graywater onto healthy soil, with no user intervention, they give no cause for concern at this stage. It is possible that pooling of some graywater at the base of the manhole is allowing bacterial growth - something which is easily rectified by correctly detailing the manhole. Further tests will be conducted at this site in the future.
Again, the community has been positive regarding the use of this type of system. With no mains sewerage in Himmeh, the reduction of graywater draining to the septic tank will result in a modest cost saving to the householder from a reduction in the need for tank pump-out.
3.8 Adasiyyah Girls' School
The girls' school in Adasiyyah has expressed interested in reusing graywater as part of an ongoing project on water conservation and water conserving gardens, being implemented by CSBE in conjunction with the Mennonnite Central Committee and the local voluntary society. The project is a collaborative one, involving the staff and students at the school. Although there is potential for reusing graywater from a number of areas of the school, a decision has been taken to begin simply. Figure 18 shows a row of drinking water faucets on the school grounds, adjacent to a planted area. It is planned to capture the drainage water from this basin and use it to irrigate a row of ornamental shrubs as illustrated in Figure 19. Since the water will be of high quality, and should contain little solid matter or organics, only a simple screen filter will be used, to protect the pipe system.
The main disadvantage of this system is the low quantity of graywater available, provided the faucets are properly closed after use. However, the reuse of graywater in such a simple, low cost way will be used to reinforce to the students the message of water demand management and to engender discussion about future possible ways to use graywater at the school and in their homes.
CSBE has a continuing commitment to the school in the design and installation of water conserving landscapes, and will be able to monitor the operation of this simple system, once it gets underway.
4.0 Legislating for Graywater in Jordan
4.1 The Current Position
The current legal position regarding the reuse of graywater in Jordan is uncertain. The relevant Jordanian regulation governing household plumbing is the ‘Sanitary Wastewater System Code', (Ministry of Public Works and Housing 1988). This provides guidelines for internal and external drainage and wastewater systems and includes extensive design guidelines for septic tanks. There is no explicit prohibition of the installation of a separate plumbing system for graywater. On the contrary, it is recommended that the toilet, bidet and urinals should not be connected into the same pipe as the floor drains and sinks, until outside the building. A suggested layout for a domestic wastewater system shows the wastewater from the toilet and bidet being kept separate from the shower and sink until outside the building where they are connected at a manhole. However, the code requires (2/4/2, page 20) that all wastewater should be discharged using a sanitary wastewater system in accordance with the recommendations laid down in the code, and prohibits wastewater discharge according to any other method. This appears to prohibit the on-site reuse of graywater.
The Ministry of Water and Irrigation has formed a committee to examine the code in light of the potential for graywater reuse, and to propose amendments that would allow the reuse of graywater more easily. CSBE is represented on this committee and has made a number of observations regarding potential legislation, based on experience elsewhere. Committee deliberations are expected to be ongoing into the summer of 2004.
4.2 Separate Regulation of Large and Small Usage Applications
Many jurisdictions which have drawn up legislation for graywater reuse, have found it beneficial to differentiate between large usage and small usage, since the implications of graywater reuse in each case are very different, and the cost and complexity of solutions are also different. Customers of a large hotel, which reuses the graywater from its staff and guests, will expect a higher degree of protection than a single household reusing its own graywater, under its own control. One of the main purposes in large usage legislation would be to provide for protection to health and environment, and ensure the responsible design, installation and operation of the graywater system. Since large usage systems will combine graywater from more than one household, additional treatment complexity, and therefore cost will result.
Low usage systems however, confined to single households, where graywater is reused solely within the property of the household, should be cheap, easy to install and maintain. They should also be cheap and easy to regulate. If the legislation forces the system to be too costly, and graywater reuse is determined by the potential user to be un-economical, then it will not be taken up. Since the potential for cost savings from household water use reduction in Jordan is fairly limited, this will be a key issue in drawing up legislation appropriate to Jordan. Legislation will have failed if;
- householders consider it too difficult to obtain a permit for a graywater system,
- it requires graywater applications to be complex and expensive,
- it is too costly for the regulatory authority to monitor and oversee.
Observers of graywater legislation in different countries have noted that the legislation implemented in the US State of California was complex and expensive to comply with, and did not lead to popular reuse of graywater. The legislation introduced in Arizona, however, followed a different philosophy, and has led to successful uptake of graywater reuse in the state.
A very useful overview of graywater legislation in a number of countries, including a comparative assessment, may be found on the Oasis Design Website, under "Greywater Policy Central" (http://www.oasisdesign.net/greywater/law/index.htm).
4.3 Management of Risk
When considering graywater systems, it is important to be realistic about risk. Wastewater professionals instinctively tend to apply existing wastewater standards and principles to graywater. However, both the quantity and quality of domestic household graywater, and the applications to which it is put, mean that standard wastewater standards which are usually applied to treated wastewater are not necessarily relevant.
For example, wastewater engineers use BOD as a key indicator of the degree of contamination of the wastewater. This is because ordinary domestic wastewater contains large amounts of sewage - the strength of which can be linked to the BOD level. However, since graywater contains no sewage, and is to be used to irrigate plants, BOD is not necessarily a useful indicator as the ‘strength' of the graywater. BOD is a measure of the degree of organic material in the water. Organic material in graywater does not constitute a major problem for either human or plant health, since it does not relate to faecal content. The organic content may be from soaps or detergents, human skin and hair, or particles of food waste. However, provided human contact with the graywater is minimized, BOD from these materials should not constitute a major risk to human health, nor should it cause a problem to plants. Organic material in the graywater will be quickly broken down by the soil. In fact, much organic material will actually be broken down into useful nitrates and phosphates which will act as plant nutrients, and are therefore beneficial to the soil.
Bacterial content (in particular the faecal coliform count) is also used as an indicator of the strength or degree of treatment of wastewater. However, with graywater, there should be little faecal material to begin with. In addition, bacteria will die soon after coming into contact with the soil, and will cause no harm to the soil or to plants. Provided human (and animal) contact with the graywater is avoided, and safeguards are applied as to the end use of the graywater (for example no irrigation of herbs or root vegetables, or vegetables which are eaten raw), the significance of the bacterial content of graywater is much less than for treated wastewater.
Standards which are applied to the reuse of treated wastewater (for example in Jordanian Standard 893) are often done so with regard to the effect on the groundwater. Nitrate content is a particular parameter of concern in many areas. However these standards are applied to instances where there is large scale reuse of treated wastewater, for example from the output of a large municipal treatment plant. Regarding graywater, since the quantities of single-household domestic graywater will be very small, the risk of any graywater leaching out of the household property into the surrounding environment or water table is very low. The immediate applicability of JS 893 and similar standards to graywater reuse must therefore be assessed on its own merit.
Minimizing risks to human health and plants is undoubtedly a key factor in the regulation of graywater. Regarding risks to human health, the hazard is low to begin with. It should not be forgotten that minutes before graywater became graywater, it was being used to shower someone, or to clean someone's clothes. Graywater is not sewage, which is why it is easier to use and deal with in the first place. There are 2 main ways to minimize risks to human health;
- treatment - i.e. remove potential contaminant material from the graywater
- prevention of contact - i.e. design a system where human contact with the graywater during application and afterwards, is minimized.
Treatment is costly and requires user intervention and high maintenance. However it is relatively simple to design a system which minimizes contact between the householder and the graywater. The average cost of domestic water in Jordan is low, especially for low quantity users, so the direct cost savings to be made from the reuse of graywater are limited. If a system costs too much to install or maintain, then it is simply not worth it to the householder.
4.4 Following the Arizona Legislation
In 2001, the Arizona Department of Environmental Quality published regulations for residential graywater reuse. These regulations are available at www.watercasa.org. These regulations follow a three-tiered approach whereby systems using under 1500 liters per day must meet a list of reasonable conditions, and are covered by a general permit without the need for the householder to apply for anything. Systems producing over 1500 liters per day require a permit, while those over 13,000 liters per day are dealt with on a case by case basis.
In the legislation, graywater is defined as wastewater collected separately from clothes washers, bathtubs, showers, and sinks. Reuse of wastewater from a kitchen sink, dishwasher, or toilet is specifically prohibited, although a revision of the regulations due in 2003 may permit the use of kitchen sink water under certain conditions.
The conditions for the private residential reuse of graywater (under 1500 l/day) include;
- avoidance of human contact between graywater and soil irrigated by graywater,
- containment of graywater from a particular residence within the property boundary,
- graywater usage only for household gardening,
- surface application of graywater may not be used for irrigation of food plants, except for fruit trees,
- surface irrigation by graywater should be restricted to flood or drip irrigation,
- sprinkling is prohibited.
In addition, the graywater should not contain water used to wash diapers or similarly soiled or infectious garments, unless the graywater is disinfected before irrigation. The graywater should not contain hazardous chemicals, for example from cleaning car parts, washing greasy or oily rags, or disposing waste solutions from home photo labs, or similar hobby or home occupational activities.
The Arizona regulations require that graywater systems should be constructed so that if blockage, plugging, or backup of the system occurs, graywater can be directed into the sewage collection system or an on-site wastewater treatment system. The graywater system can include a means of filtration to reduce plugging and extend the system's lifetime. Any graywater storage tank should be covered to restrict access and to discourage breeding of mosquitoes or other disease bearing insects. The graywater system should not be sited in a floodway and should be operated to maintain a minimum vertical separation distance of at least 1.5 meters from the point of graywater application to the top of the seasonally high groundwater table. Residences with an on-site wastewater treatment facility for blackwater must not change the design, capacity, or reserve area requirements for this facility if installing a graywater system. Any pressure piping used in a graywater system that may be susceptible to cross connection with a potable water system should clearly indicate that the piping does not carry potable water.
These regulations are widely regarded as the most progressive anywhere (see detailed discussion on the Oasis Design website www.oasisdesign.net - Oasis Design is a consulting organization with long term and wide experience of graywater systems and legislation). They have been used as the basis for new legislation in New Mexico. The tiered approach makes reuse easy for the ordinary householder and allows for innovation and flexibility of design. They do not prescribe particular design specifics and follow a performance-based approach, while the blanket prohibitions ensure the protection of human and plant health.
A booklet containing the text of Arizona's Title 18 Reuse Rules, and some explanatory notes and guidelines, is available for download without charge from www.watercasa.org.
5.0 Graywater in Jordan - the Way Forward
This report represents the current situation regarding graywater reuse in Jordan in November 2003 - at the completion of the Ministry of Planning funding component for CSBE's graywater project. It is clear that during the last 14 months, the Jordanian graywater debate has begun in earnest, although it is still at an early stage, and many people remain to be convinced.
CSBE has received funding from the British Embassy Small Grants Scheme to continue monitoring and assessing some of the ongoing graywater schemes until February 2004. Other institutions and individuals have begun to experiment with graywater and have begun to communicate openly together. It is hoped that other initiatives and schemes will be developed in the near future as graywater reuse becomes more widely known. However, there is clearly further work required in Jordan in order to provide user friendly information about graywater reuse, to demonstrate its lack of risk, and to encourage its acceptance. One encouraging development is the Ministry of Water and Irrigation's decision to form a Water Demand Management Committee to investigate how the use of graywater could be promoted and facilitated.
5.1 Long Term Project Performance
This project has seen the development of a small number of simple applications of graywater reuse. It is likely that others will be instigated as a result of the spread of information and interest generated. However, due to the short time scale of this project, a thorough assessment of the schemes - performance, appropriateness to the context, health and environmental impacts, cost - over a sufficient period of time was not possible.
What is now required is an assessment of some graywater projects over a period of time. In particular, assessment of the long term effects on soil, plants and groundwater should be made. Investigations to date have not indicated that serious detrimental effects will ensue from the long term reuse of graywater. However, none of the projects reviewed here represent a systematic, concerted attempt at making this determination to any significant degree. It is possible that a number of well-designed, properly funded pilot plants, with involvement of respected institutions such as a university or the Ministry of Water and Irrigation, will greatly help in assuaging public confidence in graywater reuse. Such projects will provide sufficient data to highlight the low level of impact which properly developed graywater schemes should have. Expansion of the scheme at JUST to include other types of plants, together with more systematic monitoring is a possible example.
Assessment of the impact of graywater schemes necessitates a degree of testing. Many decision makers will wish to see test data, before being convinced of the ‘safety' of graywater reuse. It is natural for those from a municipal water and wastewater background to desire to see water quality data, and it is also natural for those from a scientific background, and also the general public, to want to see some hard science which demonstrates the safety of graywater reuse. However, care must be taken with regard to exactly what testing can tell us about small scale graywater reuse. Municipal authorities use testing to determine the quality of the wastewater influent to and effluent from their treatment facilities. Drinking water quality is also assessed by water quality testing. Various standards exist against which the quality of water and wastewater is assessed. In each case, the actual water quality is assessed against the appropriate standard. There will be temptation to bring in a graywater standard by which the quality of graywater is assessed. However, there are important reasons why this may not be appropriate.
Graywater is produced at a household level, and is intermittent in nature. The quantity and quality of graywater produced by a household will vary both during the day, and during the week. For example, graywater output on laundry day will be significantly different to that produced on a non-laundry day. Graywater production during morning shower time will not be the same as that produced during mid-day meal preparation. Spot samples of graywater will not give meaningful results at a household level. This contrasts to the monitoring of wastewater at a municipal level, which contains significant averaging due to the large number of households contributing to the wastewater effluent, although variations in quantity from hour to hour are a known feature. Test results on graywater collected at a particular time from a particular household will reveal very little other than the characteristics of the graywater being produced at that particular time, which may have little connection to the quality at any other time. Therefore attempts to require graywater to conform to particular characteristics may be misguided, in addition to being expensive to monitor and costly to regulate.
In terms of the determination of the long-term effects of graywater reuse at a particular site, it has been argued that the soil characteristics may provide the best indication of the long-term effects of the use of graywater at that site. For example, in this report, the absence of significant contaminant levels at the HB House after a 2-year period of graywater reuse is used to argue for the low impact of this particular approach. However, ideally the soil characteristic should be monitored before irrigation by graywater is begun, as well as before and during the rainfall period, in order to mark changes in the soil as a result of flushing by rainwater.
Monitoring of the impact on the plants themselves may also be a useful indicator, although careful controls should be taken to ensure that levels of parameters monitored are a result of irrigation by graywater and not other causes.
5.3 Type of Use
It has become apparent even during the course of this short project, that different contexts require different solutions. A rural community has different expectations regarding risk and water use from a villa household. Graywater from the ablutions water produced in a mosque requires less intervention and treatment from an apartment community whose graywater will contain laundry water and will be combined to irrigate a common area. One pitfall to be avoided in the quest for graywater solutions in Jordan is a ‘one design fits all' mentality. The design of each system should be based on the initial graywater quality, the desired end use of the system and the degree of risk acceptable. This will be reflected in the cost of the system.
5.4 Concerns over Changes to Wastewater Quality
The prospect of large numbers of domestic consumers reusing their graywater sometimes causes concern amongst agencies responsible for wastewater collection and treatment. The liquid component of wastewater functions as the means of transport for the solid material, and a nightmare scenario is sometimes painted of a wastewater system whose liquid component has reduced to unmanageable levels. These nightmare scenarios are never realized, for a number of reasons. Firstly, the domestic component of municipal wastewater is not the whole story. In Jordan, the domestic component of wastewater accounts for only one component of the total wastewater budget. Domestic graywater reuse will have no impact on the industrial, commercial and tourism contributions.
Secondly, there is a limit to the number of establishments which will be able to reuse graywater for irrigation. People living in apartment blocks (most of the city of Amman) with no garden will have almost no use for graywater.
Thirdly, much of the demand for additional water comes from rural areas, where water availability is lowest. Many of these areas are not served by a mains wastewater collection system, and make use of septic tanks instead. In these cases, a reduction of water going to the septic tank is a marked advantage, and reduces the need for pumping out the tank and disposing of the waste. Graywater reuse in non-sewered areas has no effect on the mains wastewater systems.
However, the issue does lead to questions as to the wisdom of using water as a mass transport medium in such a water scarce society. In Jordan, there is an increasing push to treat the wastewater centrally to levels suitable for use in irrigation, a laudable concept, and one which is almost unavoidable in the region, given the water supply constraints. However, this should not be used as an argument against water demand reduction on the part of consumers - ‘it doesn't matter how much you use, since it will all be collected and reused anyway'. In other countries, significant moves away from centralized wastewater management are being made, and increasing interest in decentralized solutions is being developed, particularly in developing countries and notably in the Middle East region. This issue forms part of a wider debate amongst the wastewater community, but it is very unlikely that graywater reuse in Jordan will reach the level where detrimental effect on the liquidity of wastewater will be a result. Water demand reduction requires action from all consumers of water, and this includes those in the wastewater field.
5.5 Promotion & Education
Once the safety and appropriateness of graywater reuse becomes accepted by the ‘graywater community', a second argument needs to be made to the wider public, if widespread uptake of graywater reuse is to be observed. Both promotion (it's OK to do it) and education (how to do it) will be required. It is no use telling people that they should be reusing their graywater without informing them how. It is not important whether this is carried out by the NGO community or by the public sector, although the complicit backing of the Ministry of Water and Irrigation will be essential, particularly in providing appropriate legislation. The development of a model community which would have appropriate graywater reuse as a component should be considered. The Casa del Agua (Desert House), in Southern Arizona, developed by the University of Arizona and others, is one example of how such a demonstration scheme was crucial in persuading the public of the advantages of graywater and the ease with which it could be implemented. Detailed information on the Casa del Agua project is available in the E-publications section of the CSBE web site.
CSBE has produced an Arabic-language leaflet entitled ‘Graywater Guidelines', which provides basic information to those wishing to reuse graywater at a simple and basic level. Other information, covering more complex systems, may also be required for higher water use contexts.
At the end of this short 14 month project, a number of tangible successes have been achieved.
Firstly, the provision of freely available information in English and Arabic on graywater and how it is reused in other countries has allowed the opening of a important debate on the relevance and the possibility of graywater reuse in Jordan.
Secondly, the publication of this information along with the subsequent cross-communication between various groups and individuals with prior graywater experience in Jordan, has allowed for sharing of ideas and information on a hitherto unprecedented level in this field. Rather than several groups competing with each other or working in isolation, there is a spirit of cooperation and sharing as evidenced by the collaboration on the MoWI's Water Demand Committee, and at CSBE's Graywater Workshop held in September 2003, facilitated as part of this project.
Thirdly, the presence on the ground in Jordan of a number of applications of graywater reuse in varying contexts will act as a practical and visual stimulus to others and can emphasize both possibility and practicability. Although many of these applications are too recent to have been assessed fully to date, in time, their operators (some with the assistance of CSBE) will develop a picture of how they perform, how much they cost, and how the plants are affected, and what the problems are. This pool of knowledge will contribute to the Jordan experience of graywater reuse.
Fourthly, the inauguration of the Water Demand Management Committee at the MOWI will ensure that the public sector is involved in the debate. The public-private sector partnership on this committee will ensure that the various stakeholder voices are heard and will hopefully result in a practical and workable legislative arrangement which will facilitate the easy take-up of graywater reuse while protecting the public and the environment in a responsible way.
CSBE will continue to assist, monitor and assess a number of graywater schemes in Jordan for an additional six months beyond the end of the funding from the Ministry of Planning's Enhanced Productivity Program through funding provided by the Small Schemes Program at the British Embassy in Amman. A final project report will be published on the website at the culmination of that six month period.
7.0 List of Illustrations
Figure 1: Graywater reuse at its simplest.
Figure 2: Schematic of INWRDAM's graywater treatment unit.
Figure 3: Installation of INWRDAM's graywater unit at Buseira.
Figure 4: The graywater project at JUST.
Figure 5: Simple garden graywater scheme.
Figure 6: Diversion of contaminated graywater.
Figure 7: Graywater unit at RSCN Nature Center.
Figure 8: Schematic of RSCN graywater unit.
Figure 9: Schematic design of graywater system for BF House.
Figure 10: Photograph of central ablutions point, Ghuwaybah Mosque, Ghor Safi.
Figure 11: Graywater system layout at Ghuwaybah Mosque, Ghor Safi.
Figure 12: CSBE demonstration unit.
Figure 13: Previous graywater reuse in Adasiyyah.
Figure 14: Modified system with filter in Adasiyyah.
Figure 15: Potential graywater application in Himmeh.
Figure 16: Graywater capture and filtration in Himmeh.
Figure 17: Irrigation by graywater in Himmeh.
Figure 18: Existing drinking fountain at Adasiyyah Girls' School.
Figure 19: Irrigated area at Adasiyyah Girls' School.
8.0 List of Tables
Table 1: Results of water quality tests conducted on the graywater collected from the place of ablution at King Abdullah Mosque.
Table 2: Results of soil quality tests conducted on the soil at HB House - Amman.
Table 3: Results of water quality tests conducted on the laundry water of an urban house.
Table 4: Results of soil quality tests conducted on the soil at the Adasiyyah demonstration application.
Table 5: Results of soil quality tests conducted on the soil at the Himmeh demonstration application.