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Rapid growth in the demand for potable and irrigation water coupled with natural shortage and continuous restrictions in supply, primarily in and and semi-arid regions, have accelerated the search for alternative sources. Agriculture, golf courses, highways, parks and playgrounds are among the heaviest users of water due to the large areas requiring irrigation. Wastewater reuse is one possible solution that is being implemented, especially in agricultural and landscape irrigation.

The aim of the present work was to investigate the effects of irrigation with treated municipal wastewater through subsurface drip irrigation method, on growth characteristics of a lawn, to detect any changes on irrigated soil properties and consequently to evaluate the use of wastewater in water saving terms compared to freshwater use.

The experiment was conducted at the farm of the University of Thessaly. The experimental field, was separated in two parts. The first part, constituted the first treatment, which was irrigated only with fresh water from the borehole of the farm. The second part, constituted the second treatment, and was irrigated periodically with wastewater, provided by the treatment plant of the city of Volos and with fresh water. Each irrigation with wastewater was followed by two irrigation applications with fresh water, because of the lightly increased salinity that existed in the wastewater and the increased concentration of ions of chloride.

Observations of plant growth parameters included the measurements of lawn height and biomass production in regular time intervals. Measurements of qualitative characteristics of wastewater were taken, as well as soil analysis at the beginning and at the end of irrigation period.

The experimental results revealed that wastewater treatment exceeded freshwater in lawn's growth characteristics, yet no statistically significant differences were observed between the two treatments. Also, from the soil analysis that conducted in treatment that received wastewater, not any concentration of toxic elements was recorded. No significant changes in pH, electrical conductivity Fe, Zn, Cu, and Mn concentration were recorded after soil analysis in treatment received wastewater before and after the irrigation. As regards the water consumption, the use of wastewater resulted in a 32.6% saving of fresh water.