The role of non-conventional and lower quality water for the satisfaction of the domestic needs in drought management plans

Abstract

This chapter outlines the potential and role that underground low quality water and non conventional water (recycled grey water, desalinated and domestic effluent water), have and can play in the preparation of drought mitigation plans especially in relation to the satisfaction of the domestic water supply needs. Low quality underground water, if available in aquifers within the city or village perimeters, can replace 34–42% of the good quality total domestic supply, which can be used in toilet flushing and for the irrigation of gardens. Similarly grey water discharged within the domestic effluents, which may vary from 36–41% of the total supply of an average household, after collection within the household perimeter can be treated and recycled to the system thus saving a percentage equal to 36–41% of the total domestic water consumption. The low quality water abstracted from the aquifers and the grey water discharged with the household waste can be developed and made available for use within a very short time on an individual basis, the water can be used without serious problems, the capital costs involved are relatively small (can be subsidized by the government), and can be repaid within 3–4 years with the savings made from the savings of potable water. The recycled domestic effluents, whose quality is improved with tertiary treatment is suitable for the irrigation of almost all plants (Roumagnac, 1995), is a very effective method of drought mitigation (Smith and Bernard, 1995) but this usually takes a long time to materialize, 5–10 years, but the farmers already using good quality natural water will rarely accept to use it, claiming its unsuitability for irrigation. Finally desalinated water from seawater or from brackish water increases the water availability, water quality is not a problem and it can be made available within very short time. The limitations/objections for using the desalinated water are emanating from its relatively higher marginal cost than the existing supplies and the alleged adverse environmental impacts.