This paper–presents results o-f a-field-and laboratory exaniination of riine d1stinct geotextiles which were installed four to fifteen years ago as filters on agricultural drain pipes, in silt and sand soils. Field observations of geotextile materials have shown that in all cases but one that the fabrics were not clogged, the drains were clear of mineral sediment deposition and the filters had no tendency to tear while being sampled or hand washed. The one exception was a fibreglass,geotextile of an unknown age (probably greater than 15 years) which was easily torn and was brittle upon drying. ‘All geotextiles exhibited small amounts of particles trapped within and on the geotextiles surfaces. In some cases chemical deposits within the geotextiles and/or within the drains were observed. Iron ochre was the most predominate of drain eposits. Microscopic examination of the soiVgeotextile interface established the existence of a network of soil bridges and of a large quantity of macro-pores at this interface .
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