Graywater Reuse in Jordan -- continued --

Adasiyyah Demonstration Application

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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;

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. 

Al-Himmeh Demonstration Application

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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;

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.

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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.