Prepared by Stephen McIllwaine, 2003
A. 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.
B. Interaction with a number of graywater schemes that are being designed or implemented in Jordan, and provision of technical assistance to them where appropriate.
C. 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.
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.